Extreme Dissatisfaction w/ TDI

[glenn cooper]

I have had a very unsatisfactory experience with a racing industry company, and after trying to resolve the issue with them I was basically told there was nothing they could do for me.

A few years ago I decided that I would NEVER take it in the shorts again in regard to something like this, so here’s the deal my fellow racer’s – I hope after reading this you will not do business with them. Pretty simple…

I contacted Two Dogg Inc/TDI to inquire about having my RFR F1000 rotors lightened, scalloped, drilled, slotted, skimmed and cryoed. Basically a full lightening procedure.

After talking with the owner, John, I specifically mentioned that any rotor I had ever seen that had been drilled would eventually crack between the holes. I realize that rotors are a replaceable item, and eventually heat checking at a minimum would warrant replacement.

John basically mentioned to me that there were hundreds of cars running this type of full boat lightening/scalloping/slotting, skimming, etc, so he felt I should have the same results.

Fine, hey they are the experts, so I boxed them up and sent them to him.
A few days later they notify me that one of the front rotors is cracked at a mounting window/slot. I thank them for noticing this and I then have one brand new front rotor sent to them so that there is now a set of 4 to get the full treatment.

The rotors were sent back to me pretty much last minute so I had to install them at the track. I think they may not have had the cryo treatment done also, but do not have proof of that.

We installed them at the track (Rd Atlanta, 3/11), and I went out with PFC pads on for the first time. After about a lap, it was apparent something was wrong; there was a pretty big vibration straight away, so I came in. Remember one of the front rotors was brand new, and the other three were used previously with AP/Ferodo pads.

I called them and they suggested that maybe there was a pad incompatability issue as I had switched pads. I mentioned that I thought I had requested a skimming of the rotors as part of the lightening process. They replied no. Hmmm, OK…
I took a light abrasive wheel to the rotors and took off any transferred material, from the one front, and the rears which actually looked pretty good.

I then ran the rest of the weekend with no problems, everything worked great.
It was only after I got home and was going over the car getting itready for the next race that I saw what I was so concerned about and even spoke to the owner about:
Both front rotors had cracked between the holes and out from holes in about 15 to 20 spots per rotor (see pics).
After just one weekend, the one brand new and one used front rotor appeared to be junk.

I again contacted them and was told it must have been something I had done to cause this.
I reminded them that even the one brand new, never run front rotor had experienced the same fate: heavy cracking between holes, and radiating outwards from holes.
It might have been about this time that they told me the PFC 01 pad (as used by another top flight FB driver w/ similar rotor mods by them) had cracked just like this – they suspected the 01 compound was just too aggressive, so they now only scallop and do not drill his fronts.

I mentioned I had run 01’s on about everything I’ve ever raced: FM, FC, DSR w/ NO issues. They responded with something to the effect that the RFR rotors must not be very good, or lacking in carbon content or some such thing.

I said if you guys knew of a problem with running PFC 01’s on these rotors, why didn’t you advise me of this. The reply was weak, something to the effect they had just found out very recently.

In fact the problem was known to them as far back as the ARRC race in ’09!
I spoke to the other FB pilot at the June Sprints personally to get some background.

I was naturally pretty steamed, as this is quite a lot of cash to be throwing in the crapper and pulling the handle.

They advised me that the important thing was at this time to get me some new rotors so I could make the next race (VIR 2xNat). I had McLaughlin Motorsports send them 2 brand new fronts that they were then going to only scallop, slot, and cryo.

Again, time was tight and they had to next day freight them to me, and upon opening the box found a bone stock set of front rotors with NOTHING done to them.

Yeah I was pretty amazed but was really starting to think of Two Dogg in a not so reputable way, so wasn’t particularly surprised at this point.

I installed the PFC pads and ran the weekend with no problems.
In fact I ran several more races with this set of rotors and the PFC pads with NO issues what so ever.
I guess maybe it was not “something I must have done” after all. Hmmm…

I was very surprised to get a bill from McLaughlin for the replacement rotors they sent to Two Dogg.
I called McL and explained that they (TDI) said they would cover the expense.
McLaughlin spoke to them and they told him no such agreement existed.
I then spoke to Two Dogg and let me tell you after several phone calls, leaving messages, for John, speaking to two other people, I finally get to speak to the owner John and it was like speaking to someone who is well rehearsed in taking phone calls like this!

He kept on trying to get me to agree to the fact that I had sent them a job, and that they did the job I spec’d out. It was almost like a psychoanalysis session. He kept his voice very low and almost a monotone. It was a little creepy, but hey, maybe that’s the way the guy speaks – I dunno…

I mentioned they knew well in advance of a problem with another racer and an identical car/lightened TDI rotors. He said not true.
I mentioned that we had specifically spoken of cracking, his reply was something to the effect of they have no control over rotor quality.

The bottom line is that at some point you just have to trust them – they are the (supposed) experts. They have been in business a long time. They have hundreds of satisfied customers. Nothing like this has ever happened before… Yada F’in’ yada.

I could tell I was getting nowhere with Dr John, so I bid him adieu and called AMEX to put in my very first ever charge dispute.
It was then that they informed me that disputes must be put in w/i 90 days and it was actually the 92nd or 93rd day.
I feel TDI purposefully delayed communicating with me knowing of this 90 day period.
About a month ago I get a letter from AMEX saying that TDI did not get the required info back to them in the time allotted and the judgement was then decided in my favor.
However at the bottom of the page there was a line or two about some such BS in regard to “if they do send us supporting documents we reserve the right to open the case back up”.

Talk about total BS! Why do anything if they will make a decision, THEN go right back on it?

Well guess what arrived in the mail today? You guessed it, AMEX have reversed the decision and debited the $741.08 back on my account, for which I must now pay.


Which leads us here, my fellow racer friends. It is my hope that anyone who reads this will choose NOT to do business with this company in light of my experience.
Regards, GC

[glenn cooper]

...

[Purple Frog]

Coop,

You can't receive any more PMs unless you clear out (delete) some of the old ones.

[JohnPaul]

How about straightening out this ever pesistent formating issue for me please?

You're on fire tonight! Try the new poll......

[RobLav]

The other Citation I had, Sean Maisey's car now, cracked (disintegrated) a drilled rotor at Road America and ended up crashed. Why not simply use the PFC rotors with the slots? Is the weight difference worth the time/money/aggravation and increased risk?

[jnortonjr]

Coop,

I understand your position and in general I would agree. You obviously know your equipment and do a top-notch job with preparation and driving.

With that, I've had nothing but good success with TDI, especially when dealing with Rob Klein. A rotor blew up at the Runoffs, causing me to hit the wall and spend two days reconstructing instead of being on the track. I called TDI Tuesday morning and had new rotors by 2:00pm. Without that my race wouldn't have been possible.

The rotor that cracked wasn't a TDI blank and I have multiple TDI rotors that have held up very well. Unlike the factory rotors which can't seem to go more than 5 weekends without bending or cracking. Thought I would switch back to the lighter factory rotors for the week. Big mistake.

Just a different perspective.

Good luck.

JN

[glenn cooper]

The other Citation I had, Sean Maisey's car now, cracked (disintegrated) a drilled rotor at Road America and ended up crashed. Why not simply use the PFC rotors with the slots? Is the weight difference worth the time/money/aggravation and increased risk?

Rob, The RFR comes with ventilated rotors. They are quite heavy when compared to a non-ventilated FC rotor.
This whole episode was brought about by me wanting to shed weight off the car...

[Northwind]

GC,

Thanks for the post. I was considering a simliar path and have heard some stories about drilled rotor failures being common. My mind is made up now. Looks like its going to have to be a little more weight out of our mid sections.

[glenn cooper]

Dan I don't think your brakes would even be a candidate for lightening if it's the std VD or PFC replacement non-vented rotors. Just run those pups as is.
Had I kept my Nova-Diemen, I might have been tempted to go the new billet uprights that allow for radial mount twin piston PFC aluminum as Dixon is using so successfully.

[Mark G]

Glenn,
Very interesting story about the perils of drilling brake rotors.
I personally have never had my rotors drilled. I was toying with the idea one time when I had a few extra $'s that the wife didnt know about - but the more I thought about it the more I just didnt see that the weight saving was worth the trouble and expense.
On a personal note, in regards to the service and worksmanship from TDI, I have used them extensively and found John and his team to be fantastic. I couldnt recommend them highly enough.

I will certainly be staying away from drilled rotors in the future. A bit more time at the YMCA will take more weight off me than I will ever see off the rotors.
Thanks for sharing your issue.
Mark G

[Nardi]

Many years ago I bought some TDI products and thought the quality level was quite a bit below the price paid especially for their reputation at the time. I was fed a party line about how things are done. I have never done business with them since.

[dc]

any rotor I had ever seen that had been drilled would eventually crack between the holes.

...so I boxed them up and sent them to him.

If you knew that drilled rotors crack (and I have never seen one that didn't), that sounds like a risk that you willingly took to shed a few pounds. TDI shortcomings or not, sounds like a trip to the craps table in Vegas to me.

[Matt King]

Of course drilled rotors crack. I'm as surprised that any company would claim otherwise as I am that any customer would believe them.

[glenn cooper]

I was foolishly hoping to get more than ONE race weekend out of them, for the princely sum I paid.

I know, I know - What in the hell was I thinking?

The scalloping as well as the skimming (which was not done) were to account for the bulk of the weight savings.

The cross drilled rotors that I have had past experience cracking did so after several events were on my street/track RX7 at the time, a much heavier car, AND those rotors cost about $150 each.

[Brad Ellingson]

I've had nothing but good experiences with TDI. Always available for my calls, even willing to drop what they were doing to bring me some parts to the track to salvage my weekend. We are only hearing one side of the story here, and Doug is right....drilled rotors will crack...especially if you've gotten them too hot (which could have happened with a pad switch prior to scuffing away the previous pad material). I'm sorry that you had issues with them, but I, for one, will continue to do business with one of the more customer focused businesses in racing.

[Two Dogg Inc.]

Mr. Cooper, we at TDI are very happy that there are 2 sides to every story but, feel a public forum isn't the place for us to share that information. Just glad from a engineering standpoint, we know the truth!

TDI

[glenn cooper]

I've had nothing but good experiences with TDI. Always available for my calls, even willing to drop what they were doing to bring me some parts to the track to salvage my weekend. We are only hearing one side of the story here, and Doug is right....drilled rotors will crack...especially if you've gotten them too hot (which could have happened with a pad switch prior to scuffing away the previous pad material). I'm sorry that you had issues with them, but I, for one, will continue to do business with one of the more customer focused businesses in racing.

Brad, I mentioned in my OP that one front rotor was brand new, yet they both cracked after one weekend, so obviously not a "previous material" issue.

Mr. Cooper, we at TDI are very happy that there are 2 sides to every story but, feel a public forum isn't the place for us to share that information. Just glad from a engineering standpoint, we know the truth!

I bet you feel that way! And the truth is?

TDI

[Dale Carter]

I agree with Brad. John is a stand up honest guy who has been doing business with racers for years. Getting slammed for doing what he was told to do is unfair. How can someone who machines a part be responsible for something that happens to the material? Cracked, drilled rotors are not uncommon. Did the machining cause the cracks? I doubt it. John has done hundreds of these rotors. Something else was going on here. I can understand Coop is unhappy but this was a cheap shot.

[brownslane]

is not THAT something went wrong, it is more WHAT THEY DID when they found out something went wrong.

We all know that "stuff" happens in racing. We are exploring the very engineering limits of mechanical componentry in the constant search to maximize results.

We all know Coop pretty well. He is a knowledgeable, honest and straight guy. I believe everything he has said about TDI. Remember, he was the customer here. If TDI has the actual engineering "truth" about this, then let us know! If they truly charged for services they did not perform, then they need to be accountable. Coop only posted here out of frustration and I can assume he did so in the hope that TDI would have stepped up to the plate in an attempt to resolve the "difference in opinion" as I am sure TDI would describe it.

Bottom line is that we (the racers and customers) have to place our faith and trust in suppliers (that would be TDI). We have to trust they would look out for our (and their) interests...and that would including recommending certain combinations that they know would work, and dissuade us from using combinations that they have seen fail. That would include cross-drilling; if it is junk, then tell us so! If certain pads will cause failures, please share it with us!

I am in the business; some days I am a hero, some days I am a zero! But I always try to appease the customer even if the problem is an ID # ten T (write it out on a piece of paper). Sometimes, in business, you need to take the customer side and "suck it up" a little bit! It is apparent that John at TDI is ticked and is unwilling to accept any responsibility for the problem. He might be right. But then he could have told Coop he would not drill the rotors as they will fail rather than taking his money and then walking away.

This became a bun fight the minute Coop called with the failure complaint; TDI appears to be totally unresponsive to Coop's complaint and did nothing to assist him. How should he feel?

In Coops place, perhaps a simple offer to have the replacement rotors skimmed, drilled, slotted and cryo-treated but there is NO warranty! That is what I would have done!

A phrase I use often regarding customer complaints I have heard over the years....."don't give me what I asked for, give me what I need"...Perhaps if TDI had to do it over again, they would have given Coop the recommendation that certain pads interact poorly, or that no warranty would be available on drilled rotors...because they will fail.....then, if Coop still wanted to drill, etc he would have been fully advised and would have known that the risk was all his.

He trusted they would make recommendations. They apparently did not.

If pride gets in the way of managing a business, you will save face and lose customers.
Do that long enough and you will lose the business.

I agree with Brad. John is a stand up honest guy who has been doing business with racers for years. Getting slammed for doing what he was told to do is unfair. How can someone who machines a part be responsible for something that happens to the material? Cracked, drilled rotors are not uncommon. Did the machining cause the cracks? I doubt it. John has done hundreds of these rotors. Something else was going on here. I can understand Coop is unhappy but this was a cheap shot.

[pwd911s]

Glenn Cooper.
As stated above, there are two sides to every story. TDI has been in business for a long time with some great success stories. Your anger and accusations are as another person stated "on fire", Warranted.....I personally doubt it.

I have the authority to state this without hesitation because we have 6 years of purchases with Two Dogg. We have a respectable track record to stand on, one we definitely give due credit to the components from Two Dogg. To this point we consider John Taylor a vital part of our Team and a part of the solution to our successes.

We've run Two Dogg Rotors and hats, lightened gear box, exquisitely reworked gears and cluster, custom engineered and fabricated components that have allowed us to run fast, light and up front. I'm speaking of 6 years worth of wearable components, reordered or rebuilt that operate flawlessly. That's over seven sets of rotors. All without ANY issues or problems. AT ALL!!! They (Two Dogg) have been responsive and have gone FAR beyond in the area of service and support, comparable or exceeding that of any other vender that we have worked with in the industry and there a lot of really good people out there.

Mr. Taylor is a very reasonable and principled man, who runs his business in the same fashion.

I've found people are willing to fight if you dig your heels in, expect unreasonable results and accept no portion of blame. But when treated with respect and latitude, results are achieved. It's unfortunate that you couldn't settle your differences without stooping to the levels of a forum malign.

Paul Descoteaux
Kautz Racing
Www.kautzracing.com

[starkejt]

So far, I see one guy (Tom Owen) who understands customer service.

[blackbmwk1200r]

We all know Coop pretty well. He is a knowledgeable, honest and straight guy. I believe everything he has said about TDI.

I do not know Glen Cooper personally but I have read many Glen Cooper posts in the time I have been an Apex member. I found them to be detailed, well thought out, even handed and very supportive of others. He consistently takes responsibility and openly shares the humor in the problems and mishaps that are of his own making.

The content and pattern of his posts on this site create a lot of credibility for him with me as I think they should for many. I fully believe what he has reported here.

[R. Pare]

Can't and won't comment on the Coop/TDI issue since I do not have all of the information needed to place any faults, but will instead offer some advice:

Have been doing rotors at every level of racing for 30 years now, so I think I can safely say that drilling them is something you do at your own risk.

Both the rotor and the pad material make a big difference as to how much risk you are taking.

Gray CI - The vast majority of OEM ( and cheaper racing) rotors are made from gray CI, because it is cheap, transfers heat quickly, has high self-damping, and almost anyone can pour it. If your rotors are based on modified OEM rotors, most likely they are gray CI. Gray CI is the most prone to thermal stress fracturing because the graphite in the material is of flake form - lots of sharp edges that act as stress risers. Drilled holes just increase thermal gradient events (temperature differences at the edges of the holes), which add to the thermal stress levels, causing cracking very quickly.

Ductile CI - Also called Nodular, since the graphite is in roughly spherical form (kinda lumpy, like a raisin). The lack of sharp edges substantially decreases the onset of thermal micro-cracking, which allows the rotors to operate at temperatures well above that of gray CI rotors. However, thermal gradients at the holes will still cause cracking over time. Ductile does not transfer heat as quickly as gray CI, nor does it have as good self-dampening, and is more expensive, so it is used by OEMs only where really hard use is expected. Most vented rotors are Ductile, but vented rotors can also be poured from high carbon content gray - a lot depends on the viscosity of the molten material and its ability to travel through thin sections ( in gravity-feed pouring - spin casting is a different story).

CGI - Compacted Graphite Iron. Basically cast iron alloyed with a small amount of titanium, which causes the graphite to form into a worm-like structure. Has the best high temperature strength characteristics, and has nearly the same thermal transfer and self-dampening characteristics as gray. Used extensively in Europe for train and big truck rotors and drums, and gaining use everywhere for thin-walled engine blocks, etc. I'm pretty sure that the PFC solid rotors are CGI, and most likely the best from Alcon, AP, and Brembo, but you will definitely pay extra $$ for them.

Steels - Lousy as a rotor material compared to CI because its Cf is about half that of CI, but is much more resistant to thermal cracking, so drilling is not anywhere near as much of a risk. Motorcycles use stainless simply because it does not rust.

Pad material: Pads heavy in metallic content tend to generate hight instantaneous interface temperatures, so more care needs to be taken during the bed-in process.

In all cases, drilling is really considered a last-ditch effort to help eliminate fade in extreme use, but with the knowledge that the rotors can and will crack.

If you insist on drilling, you can help your cause by the following:

1 - Make sure the rotors are at least Ductile, NOT gray.

2 - Chamfer the edges. Best done with a radiusing cutter rather than with a standard 90 degree countersink because the countersink will still leave sharp corners at the edges of the chamfer itself.

3 - Once the holes are drilled and chamfered, use a ball bearing and a press to compress the material at the hole edges. Adding compressive stresses will help offset thermal tensile stresses and help decrease (but not totally eliminate) cracking.

4 - Bed your rotors properly. This means bringing them up to operating temperature gradually by only using light to medium braking for the first few laps, followed by a cool-off period - different manufacturers will recommend slightly different procedures, but in general this is the most common for good results. I've seem a ton of brand new rotors junked in their first session because of not bedding them in properly.

In general, I do not recommend drilling your rotors, mainly because of the risk of catastrophic failure.

[Purple Frog]

My experience with TDI: (scale 1 to 10, 10 being high)

Knowledge of metal working/fabrication .... 10
Knowledge of Reynards ....... 11
Workmanship.................... 10
Timeliness ................... 8
Communication skills w/customer.... 2
Feeling that you are important to them... 1

I have often recommended them to racers since my transaction, but always with the cavet that they better have a thick skin going in.

And, I will still do business with them , with an open mind about what I'm getting into as far as customer service.

So... i can see how this might have shook out as Coop says. too bad for both parties.

[Brad Ellingson]

This became a bun fight the minute Coop called with the failure complaint; TDI appears to be totally unresponsive to Coop's complaint and did nothing to assist him. How should he feel?

Again, two sides to every story. You absolutely CANNOT say that TDI has been unresponsive to Coop's complaints and did nothing to assist him based on what has been written here. Coop decided his best course of action was to air dirty laundry here....quite within his right. TDI has stated a public forum is not the place they wish to handle this dispute...can't fault them for that. Different folks will have their different experiences with TDI. PF says he didn't feel as though he was important...I have had a VERY different experience with them. I've never personally met Hell No Kitty (Coop) so I cannot attest to his character. Based on what I've heard from other folks, he seems a stand up guy. I KNOW John is. Hopefully the two parties will resolve the dispute, though it sounds like they already have as Coop has his money back.

[brownslane]

Brad, in fact the reason that Coop has "aired the laundry" is because he did not get any money back, a reasonable explanation, or an offer of any sort of credit. My understanding is that the fact that he received no explanation, poor service and no refund is the reason why he felt he had no other alternative.

Here is the sad part; TDI work their backsides off to service the racing community; that seems to always involve "extras" whether that means working late, dropping everything els for a rush shipment, answering calls and resolving problems constantly, and often for customers who don't fully aprpeciate the effort being made for them.

Glenn Cooper has been a safe, spirited and involved competitor in SCCA for a long time. he has always paid his bills, listened to other opinions, makes decisions based on all information he has at hand. He (unlike me) is a pretty cool-headed dude. He is also very reasonable and understands what things can happen. I truly believe, whether perceived or otherwise, he feels he has been cheated and disrespected. I can both understand the circumstances that have put him in this position and I can also fully understand his response.

You are not getting what is really going on here! This is less about what happened with the brake rotors (although the whole reason for the complaint) but the lack of followup or customer support he did not receive.

Somebody said it before in this post; they expect quality work from TDI....they do NOT expect customer service. In this particular instance it would appear to me that Coop got neither.

Again, guys, the answer is simple. John and Coop need to be able talk about the problem and John needs to take the customer side of the desk....his intransigence in dealing with a customer is hurting his business reputation. Even if John were to feel taken advantage of, his business cannot afford "bad press" from a respected guy like Coop.

Here is an example; I just finished repairing an early Series 2 XJ sedan (Jaguar) It took me a YEAR to fix the darn car (not proud of that). But the car came as a basket case, did not run, there was no wiring harness, no diagrammes and parts missing. I ended up giving up on an OEM parts supply challenge and instead BUILT a custom ignition system for the guy. Now, I did this part time because the guy did now want to pay me full-time to learn all there was about this specific one-year model. So I took it slow, using "down time" to do the work. I have about 70 hours on the car; legitimately I should be able to bill him for this; nobody else (he had tried a couple of other shops) could fix the thing, in fact, they made it worse.

So I have $800 in parts and 70 hours of labor. If I billed him for it all, I would be charging more than the car is worth. So I did not wait for the peeing match over a bill. I just "sucked it up: and charged him what I felt he could stomach...and I charged him 20 hours. Not a great way to get rich, but I feel an obligation to provide value to my customers; typically that involves solving a problem for them.

I have found that, if I truly solve the customers' problem, rarely does he leave the shop unhappy. That also means I live in a smaller house, don't drive nice, new cars. But I can call most of my customers "happy", I get tons of recommendations, and I sleep well at night.


Sorry for rambling on! I really see that both parties are NOT wrong. I also see a direct and reasonable solution to the problem.

This thread has degenerated into an argument about whether the shop in question has done good work in the past. That is not the point!

As prospective consumers, it sure would be great to hear from the experts here. Why doesn't TDI give us an explanation why and how failures like these occur, and educate us on their recommendations as to how to avoid said failures in the future. To hide behind "this is not the forum to discuss this" smacks of "I told the guy to bugger off, now leave me alone".

Richard Pare has given us more information related to brake rotor problems than the guys who do this work for a living. If they are the experts, then perhaps they would be willing to share some of this and educate us as to why the rotors failed so quickly? I, for one, could benefit from the knowledge, and would be more inclined to send work to a shop that can demonstrate their command of this specialized field.

Brad, you share the same sentiment; I know that Coop was willing and able to "get together" with John and resolve their differences. So you are urging John at TDI to contact Coop and sort this out; super idea.

With that said, I still would appreciate any knowledge on braking systems that anyone wants to share. Ya, I've seen a lot, but I haven't seen it all Like the new radial mounts....they work better because they are a stiffer caliper?

Best, Tom

Again, two sides to every story. You absolutely CANNOT say that TDI has been unresponsive to Coop's complaints and did nothing to assist him based on what has been written here. Coop decided his best course of action was to air dirty laundry here....quite within his right. TDI has stated a public forum is not the place they wish to handle this dispute...can't fault them for that. Different folks will have their different experiences with TDI. PF says he didn't feel as though he was important...I have had a VERY different experience with them. I've never personally met Hell No Kitty (Coop) so I cannot attest to his character. Based on what I've heard from other folks, he seems a stand up guy. I KNOW John is. Hopefully the two parties will resolve the dispute, though it sounds like they already have as Coop has his money back.

[Brad Ellingson]

To hide behind "this is not the forum to discuss this"

I don't believe that from an engineering standpoint they are not willing to discuss. I believe what they were referring to was the dispute itself. I have always known John to be willing to take the time to discuss things if you take the time to call. You cannot fault anyone at TDI for not wanting to spend the day typing on the computer about braking systems. I would be willing to bet that if you called, they'd be more than happy to talk to you...if not right there and then, I am sure at a mutually agreeable time.

[R. Pare]

Richard Pare has given us more information related to brake rotor problems than the guys who do this work for a living. If they are the experts, then perhaps they would be willing to share some of this and educate us as to why the rotors failed so quickly? I, for one, could benefit from the knowledge, and would be more inclined to send work to a shop that can demonstrate their command of this specialized field.

Actually, I DO do this for a living, among many other product lines, and have done so for longer than I care to think about.

One thing for sure in this business, it takes forever to build up a good reputation, but probably only one dissatisfied customer to ruin it, so you have to do your best to make sure that your customers are happy, or at least understand why they had a problem.

As to the causes of Coop's problem, I can offer this as a guess (and obviously could be wrong in this instance):

1 - Possible too aggressive bedding-in of the rotors.

2 - It the old rotors were not cleaned of their old pad material, the new material (the PFC01 pads) would react badly with it, causing the initial vibration issue.

3 - If the old pads material was a carbon metallic, the simple abrasive cleaning he did after the first session most likely was not enough - carbon metallic pads don't just deposit material on the surface, it actually embeds itself a few thou', which is why it is recommended to cut .010' off the surfaces when switching compounds.

4 - If Coop did not sand the pad surfaces as well as clean the rotors, there would have been a smear of old pad material left on the new pad surfaces. Again, this incompatibility of materials would most likely cause higher interface temperatures, in turn causing higher temperature gradients.

5 - No clue as to what the rotor material was, but very possibly, based on his results even in light of the material issues, these rotors were gray CI. However, this sort of cracking is possibly also very possible with ductile when you combine the material issue with the drilling.

As I said, all of that is speculation as far as Coop's problem, but advice to use as a guide for everyone else.

[JerryH]

I've run lots of drilled rotors over the years.....and all of them cracked after several races.....except the ones we bought from TDI. We had them on a 97 VD FC for over 20 weeekends with no problems (unless you count pad wear a problem)....and yes we hammered them......pole at Runoffs 2000. I don't know what material TDI makes them from, but Richard is right on about the materials. We have had very bad experience cracking grey cast iron rotors....and even ductile iron ones. So we stopped drilling any rotors.....bought them from TDI instead.

Vented rotors seem to be much worse at cracking (when drilled) than solid ones .....only tried that a couple of times......with bad results both times. Maybe that was a contributing factor.

Richard, do you concur that vented rotors are more prone to cracking?

Jerry Hodges

[R. Pare]

Can't give a definitive answer there. The majority of my experience with vented rotors is with CART, GTP, Nastycar, F. Atlantic and Trans Am, where they were always pretty much max stressed thermally. At the time (mid-late '80s' into the early 90's) the AP rotors were the worst when drilled (even undrilled), and the Alcons the best (CGI material, I believe), but would still crack when drilled (even with radiused and compressed hole edges), especially on a P-car. Once we introduced the Alcon R4 pad, the need for drilling for fade resistance disappeared.

If comparing a solid rotor under the same thermal inputs (car weight, speed, and pad material) to a vented rotor, I would expect the vented rotor to cool much quicker, so it might be possible to see bigger gradients right around the holes edges during the braking event, but I have no real data to prove or disprove that theory - never did any sort of back to back testing of that sort ( I wouldn't even THINK about running a solid rotor on any of those cars!)

Sorry!

[nulrich]

Why don't you switch to a solid rotor? That will save you weight and also improve your braking consistency. An FB car is slightly faster but also lighter than an F2000 car, so the thermal load is very similar. No reason to use vented rotors unless you want higher unsprung weight.

In addition to the material choices Richard explained very well, there are also significant differences in processing than can affect rotor durability and even performance. There's a reason we fit Alcon rotors to all of our new cars.

I wouldn't use drilled rotors unless you are willing to sacrifice durability for a very small improvement in unsprung weight. I like the S-groove that Alcon uses, and cracking shouldn't be an issue.

Nathan

[Rick Kirchner]

As a data point: I had a lot of warpage problems with the front rotors on our Nissan Altima, so I bought some drilled and vented ones. The manufacturer used a ball-end cutter to radius the holes. Used 'em for three years of mountain driving with no cracking. Also used Porterfield pads.

When they last got replaced I bought "OEM style" discs, and the warpage came back. Turns out the warpage problem was due to not using a torque wrench on the lugs. Never ran into that before with steel wheels, but the hats are so damn thin now that they'll distort and then you get pad transfer at various places around the disk. If you take the wheels off and run a dial indicator around, you'll find them in spec. Put the wheels on and they'll shake (especially at low pedal pressure).

If you have a car that's problematic with "warping", sand the disks, torque up the lugs, and see if the problem goes away.

Just some brake system trivia.

[Offcamber1]

Particularly Richard Pare.

I don't think anyone's future purchase habits changed due to this thread, but for me it was worthwhile reading as a learning experience. I question the value of lightening brake and rotating components to such a degree when simply running for trophies. Professional drivers are paid to take such risks, most of us are not.

[racersonly]

Glenn,
I can relate to your dissatisfaction with TDI. Many years ago, I too had a very negative experience, and I promised myself that I'd never do business with them again.

[R. Pare]

Part of the warpage problem on many rotors is inadequate stress relieving. The OEMs usually don't bother since they don't expect hard use, plus they rarely go under 1/2' in thickness.

For thinned down OEM rotors, or any made from dedicated castings or cut from bar stock, at least one stress relieving is a must, especially if the rotor is going to be solid mounted. Generally, the rotor blank will go thru at least 2 stress relievings - one before any machining, and one just before final surfacing - some companies do 3 treatments - it depends on the expected final use and what the market will bare.

Many of the custom rotor houses may only do one stress relieve simply because of costs - a batch of rotors, whether it be just one or 20, will cost, at a mimimum, $150, and go up from there depending on the actual processing weight ( with the $150 end being the minimum charge for even just one rotor), so if the manufacturer doesn't make a LOT of rotors all of the time, they will generally skip a second or third process to save the customer some $$.

If you are going really high-end, the rotors will also get cryo treated, but you will definitely pay a lot extra for it.

Even if the rotor only gets one stress relieve done to it, hat doesn't necessarily mean that the rotor will warp when used - that depends more on the bed-in process.

[formulasuper]

I've been drilling & selling brake rotors for classic (70's) street & racing motorcycles for 5 years & have never had any complaints about cracking, however they are stainless steel. Years ago I did try drilling my rotors on my then current F500 car & sure enough they cracked between the holes even though I camfered them on both sides. I have not drilled my current car's rotors (RT5 Formula S) for this very reason. I have found drilling actually reduces weight very little & is mostly beneficial for wet weather racing.

[Jim Gustafson]

Mr. Cooper "All Knowing One". This was really lame.

Jim Gustafson
Visual Communications

[stonebridge20]

[quote]

If you are going really high-end, the rotors will also get cryo treated, but you will definitely pay a lot extra for it.

I guess it depends on WHO does your Cryo treating !

Prices on request

[glenn cooper]

Glenn,
I can relate to your dissatisfaction with TDI. Many years ago, I too had a very negative experience, and I promised myself that I'd never do business with them again.

Interstingly enough, the "Fan Mail" between PM's and here is right around 50%, which in my book is not horribly impressive...

Particularly Richard Pare.

Man know's his stuff, nuff said. Thank you very much RP for taking the time to educate the masses.

I don't think anyone's future purchase habits changed due to this thread, but for me it was worthwhile reading as a learning experience. I question the value of lightening brake and rotating components to such a degree when simply running for trophies. Professional drivers are paid to take such risks, most of us are not.

I'd say folks who were tempted to have rotors cross-drilled might be having second thoughts.

Why don't you switch to a solid rotor? That will save you weight and also improve your braking consistency. An FB car is slightly faster but also lighter than an F2000 car, so the thermal load is very similar. No reason to use vented rotors unless you want higher unsprung weight.

In addition to the material choices Richard explained very well, there are also significant differences in processing than can affect rotor durability and even performance. There's a reason we fit Alcon rotors to all of our new cars.

I wouldn't use drilled rotors unless you are willing to sacrifice durability for a very small improvement in unsprung weight. I like the S-groove that Alcon uses, and cracking shouldn't be an issue.

Nathan

Thanks Nathan. The rotors on the RFR are about an inch thick, with the caliper being correspondingly wide, so not quite a bolt on change.
I HAVE thought about having the calipers machined so that they would be thinner, allowing a solid rotor to be used.
I'm not sure if this could even be done...

Actually, I DO do this for a living, among many other product lines, and have done so for longer than I care to think about.

One thing for sure in this business, it takes forever to build up a good reputation, but probably only one dissatisfied customer to ruin it, so you have to do your best to make sure that your customers are happy, or at least understand why they had a problem.

As to the causes of Coop's problem, I can offer this as a guess (and obviously could be wrong in this instance):

1 - Possible too aggressive bedding-in of the rotors.

2 - It the old rotors were not cleaned of their old pad material, the new material (the PFC01 pads) would react badly with it, causing the initial vibration issue.

Rotors were supposed to be skimmed as part of the job - they were not, MY BAD for not catching that.

3 - If the old pads material was a carbon metallic, the simple abrasive cleaning he did after the first session most likely was not enough - carbon metallic pads don't just deposit material on the surface, it actually embeds itself a few thou', which is why it is recommended to cut .010' off the surfaces when switching compounds.

See above.

4 - If Coop did not sand the pad surfaces as well as clean the rotors, there would have been a smear of old pad material left on the new pad surfaces. Again, this incompatibility of materials would most likely cause higher interface temperatures, in turn causing higher temperature gradients.

See above

5 - No clue as to what the rotor material was, but very possibly, based on his results even in light of the material issues, these rotors were gray CI. However, this sort of cracking is possibly also very possible with ductile when you combine the material issue with the drilling.

As I said, all of that is speculation as far as Coop's problem, but advice to use as a guide for everyone else.

Brad, in fact the reason that Coop has "aired the laundry" is because he did not get any money back, a reasonable explanation, or an offer of any sort of credit. My understanding is that the fact that he received no explanation, poor service and no refund is the reason why he felt he had no other alternative.

Here is the sad part; TDI work their backsides off to service the racing community; that seems to always involve "extras" whether that means working late, dropping everything els for a rush shipment, answering calls and resolving problems constantly, and often for customers who don't fully aprpeciate the effort being made for them.

Glenn Cooper has been a safe, spirited and involved competitor in SCCA for a long time. he has always paid his bills, listened to other opinions, makes decisions based on all information he has at hand. He (unlike me) is a pretty cool-headed dude. He is also very reasonable and understands what things can happen. I truly believe, whether perceived or otherwise, he feels he has been cheated and disrespected. I can both understand the circumstances that have put him in this position and I can also fully understand his response.

You are not getting what is really going on here! This is less about what happened with the brake rotors (although the whole reason for the complaint) but the lack of followup or customer support he did not receive.

Somebody said it before in this post; they expect quality work from TDI....they do NOT expect customer service. In this particular instance it would appear to me that Coop got neither.

Again, guys, the answer is simple. John and Coop need to be able talk about the problem and John needs to take the customer side of the desk....his intransigence in dealing with a customer is hurting his business reputation. Even if John were to feel taken advantage of, his business cannot afford "bad press" from a respected guy like Coop.

Here is an example; I just finished repairing an early Series 2 XJ sedan (Jaguar) It took me a YEAR to fix the darn car (not proud of that). But the car came as a basket case, did not run, there was no wiring harness, no diagrammes and parts missing. I ended up giving up on an OEM parts supply challenge and instead BUILT a custom ignition system for the guy. Now, I did this part time because the guy did now want to pay me full-time to learn all there was about this specific one-year model. So I took it slow, using "down time" to do the work. I have about 70 hours on the car; legitimately I should be able to bill him for this; nobody else (he had tried a couple of other shops) could fix the thing, in fact, they made it worse.

So I have $800 in parts and 70 hours of labor. If I billed him for it all, I would be charging more than the car is worth. So I did not wait for the peeing match over a bill. I just "sucked it up: and charged him what I felt he could stomach...and I charged him 20 hours. Not a great way to get rich, but I feel an obligation to provide value to my customers; typically that involves solving a problem for them.

I have found that, if I truly solve the customers' problem, rarely does he leave the shop unhappy. That also means I live in a smaller house, don't drive nice, new cars. But I can call most of my customers "happy", I get tons of recommendations, and I sleep well at night.


Sorry for rambling on! I really see that both parties are NOT wrong. I also see a direct and reasonable solution to the problem.

This thread has degenerated into an argument about whether the shop in question has done good work in the past. That is not the point!

As prospective consumers, it sure would be great to hear from the experts here. Why doesn't TDI give us an explanation why and how failures like these occur, and educate us on their recommendations as to how to avoid said failures in the future. To hide behind "this is not the forum to discuss this" smacks of "I told the guy to bugger off, now leave me alone".

Richard Pare has given us more information related to brake rotor problems than the guys who do this work for a living. If they are the experts, then perhaps they would be willing to share some of this and educate us as to why the rotors failed so quickly? I, for one, could benefit from the knowledge, and would be more inclined to send work to a shop that can demonstrate their command of this specialized field.

Brad, you share the same sentiment; I know that Coop was willing and able to "get together" with John and resolve their differences. So you are urging John at TDI to contact Coop and sort this out; super idea.

With that said, I still would appreciate any knowledge on braking systems that anyone wants to share. Ya, I've seen a lot, but I haven't seen it all Like the new radial mounts....they work better because they are a stiffer caliper?

Best, Tom

Thank you Tom

Again, two sides to every story. You absolutely CANNOT say that TDI has been unresponsive to Coop's complaints and did nothing to assist him based on what has been written here. Coop decided his best course of action was to air dirty laundry here....quite within his right. TDI has stated a public forum is not the place they wish to handle this dispute...can't fault them for that. Different folks will have their different experiences with TDI. PF says he didn't feel as though he was important...I have had a VERY different experience with them. I've never personally met Hell No Kitty (Coop) so I cannot attest to his character. Based on what I've heard from other folks, he seems a stand up guy. I KNOW John is. Hopefully the two parties will resolve the dispute, though it sounds like they already have as Coop has his money back.

Thanks Brad - You do know that my being "stuck" with the bill prompted this whole thing, right?

I do not know Glen Cooper personally but I have read many Glen Cooper posts in the time I have been an Apex member. I found them to be detailed, well thought out, even handed and very supportive of others. He consistently takes responsibility and openly shares the humor in the problems and mishaps that are of his own making.

The content and pattern of his posts on this site create a lot of credibility for him with me as I think they should for many. I fully believe what he has reported here.

Thank you BlkBeemuh

So far, I see one guy (Tom Owen) who understands customer service.

ALLWAYS the voice of reason!

Glenn Cooper.
As stated above, there are two sides to every story. TDI has been in business for a long time with some great success stories. Your anger and accusations are as another person stated "on fire", Warranted.....I personally doubt it.

I have the authority to state this without hesitation because we have 6 years of purchases with Two Dogg. We have a respectable track record to stand on, one we definitely give due credit to the components from Two Dogg. To this point we consider John Taylor a vital part of our Team and a part of the solution to our successes.

We've run Two Dogg Rotors and hats, lightened gear box, exquisitely reworked gears and cluster, custom engineered and fabricated components that have allowed us to run fast, light and up front. I'm speaking of 6 years worth of wearable components, reordered or rebuilt that operate flawlessly. That's over seven sets of rotors. All without ANY issues or problems. AT ALL!!! They (Two Dogg) have been responsive and have gone FAR beyond in the area of service and support, comparable or exceeding that of any other vender that we have worked with in the industry and there a lot of really good people out there.

Mr. Taylor is a very reasonable and principled man, who runs his business in the same fashion.

I've found people are willing to fight if you dig your heels in, expect unreasonable results and accept no portion of blame. But when treated with respect and latitude, results are achieved. It's unfortunate that you couldn't settle your differences without stooping to the levels of a forum malign.

Paul Descoteaux
Kautz Racing
Www.kautzracing.com

I know, now you imagine how suprised I was when the whole thing went to hell!
One man's forum malign is another's attempt to ensure his fellow racer's do not succumb to the same fate.

I agree with Brad. John is a stand up honest guy who has been doing business with racers for years. Getting slammed for doing what he was told to do is unfair. How can someone who machines a part be responsible for something that happens to the material? Cracked, drilled rotors are not uncommon. Did the machining cause the cracks? I doubt it. John has done hundreds of these rotors. Something else was going on here. I can understand Coop is unhappy but this was a cheap shot.

Said the machinist about the other machinist (j/k Carter - keep them panties wad free!)
You've gotta know this was not like me requesting a bracket from you and giving you wrong dimensions to which you make the part from, then have me bitch when it won't bolt straight up.
In my OP I detail the problems these rotors have had and how the other person now does not get his RFR rotors drilled, due to the same thing that happened to me, but a year and a half prior.
It's all explained in my OP, I swear!

My customers rely on my knowledge in my field. I get calls all day long in regard to proper procedures and questions on product application. If they do an induction system cleaning on an electronic throttle body Nissan, I tell them expressly to not touch the throttle plate, which most techs will do to clean that plate/throttle bore contact area and back side of the plate real well.
On a GM truck w/ elec throttle body you can poke the plate all day long, nothing will fault. Do it on the Nissan and you are buying a new TB, which btw used to cost about $700 for a new one, which I bought for my customer after the first incident.
All my customers then rec'd detailed (printed and initialed by shop personell) instructions on how to perform this service on a Nisasan. I did not forget to tell any of them. I educated my customers with knowledge that I had gained from a problem that had happened in the past...

[glenn cooper]

That I am not so flashy at multi quoting either!