Originally Posted by Mesamaui
Two thoughts (well one a question really)
1. What kind of vehicle does a YAC come from? I am not very familiar with them.
2. Two great sources of information:
The Dave Bean BD/English Ford Catalog.
Burton's Power catalog from England.
Both have not only parts for sale, but also objective, useful commentary and notes on the various English Fords. (Which now I see I could have used for reference on the YAC)
I read mine at lunch.
Mine is a YB modified as a light YBM with solid cams and a bit higher compression and 220Hp all at low 7200 rpm
The YB came in 90’s Ford Sedan Sierra in the UK, almost identical to the pinto engine Block so easy to adapt to the Hewland Transaxle
The YBM was available from cosworth as a crate full Race engine package with around 270Hp
Engine Bay "legs"
As I mentioned in an earlier post, my welder does not like wooden jigs. I was hoping that using TIG would mean less heat generated and wood would be ok. Not so. So my compromise was to develop a jig where I could fab and fit up the parts needed and then temporarily clamp them for the welder. You will see in the photos that I used clecos and small c-clamps to hold the pieces.
The plates that join the two members of a leg are typically seen only on the upper two legs. As I wanted them to align and hold the leg parts, I put one on both upper and lower legs. They are attached to the tubes my rosette welds so I added two rivet holes between the rosette weld holes. After paint the engine bay, I will add the rivets. I used these rivets holes for my clecos.
So, in the end, I fabricated, fitted and deburred the pieces, took them to my welder and he clamped them to his table and then welded them.
I am happy with the results and have kept them jig for future use. In a weird way, I enjoy building precise and accurate jigs as much as any of the other work that I am doing. They are very satisfying. I start with a baseline and then develop a centerline for the part that is perpendicular to the baseline. As I want the two lines to be completely perpendicular, I use a method that does not rely on a square of any type to develop the 90 angle. What I did was use a large compass. I drew the baseline and picked a point on the line where I wanted my centerline. Then using the compass, I swing two arcs from the center point across the baseline, one on either side from the center point. From these two points, I increase the length (as far open as I can make the compass) and swing an arc from each. A line drawn from the original center point through the intersection of the two arcs is perfectly perpendicular to the baseline. I do all that and then check it with a square. What does that say about me?
Anyways, here are them photos.
As usual, any and all comments are welcome.
What you are doing regarding the wood jigs is great for parts fit up. And on sites like Locost USA ,I see quite a few people using wood for welding jigs as well. However they are generally doing their own welding. Quite a few Pro welders will not like them.
The next level in jigs is to make something similar in metal. More time and material cost but you will recoup at least some of that in reduced billed time at the welding shop. It's perhaps difficult to justify when only making one car. Jigs and fixtures can easily end up being a bigger project than the parts themselves, especially for a complex structure like your rear subframe.
Greg
Greg,
You have me thinking. I have built a fixture for the rear subframe out of wood. Maybe best to redo in metal. Here are some pictures of where I am right now.
I added the two braces because I found out that by itself, the bulkhead would not sit plumb and I wanted be certain that the ends of the leg would align vertically at the rear. Again, after aligning the parts, I cleco'd the legs to the bulkhead.
I am now thinking that it would be better to rebuild the fixture in metal so that I can assemble and align the parts and then transport the entire fixture to the welder. Or, better yet, maybe have him come to my place to do the welding.
Any thoughts?
Anyone?
Bueller...…...Bueller....
what about doing a small copper inlay into the fixture underneath each joint that has to be welded?
Captivating. Hands down, no BS, this is going to be fun.
V/r
Iverson
Rick,
Would the purpose be to act as a heat sink? Has anyone tried it? It would not be hard to do. Probably the least amount of rework.
Thanks for the suggestion.
Chip
A large jig like this might still be acceptable to your welder if you make a 5 or 6 inch diameter hole at each weld point. Reduce or eliminate burning and also the benefit of full 360 degree access to the weld area. It might still require some additional clamped on metal bracing to keep everything 100 percent square but the wood is a good starting point.
Greg
That's a better idea than mine. The copper was just to provide a surface that wouldn't burn (not really a heat sink) and keep the weld from sticking to it, but a hole is better.
All,
After consideration, I'm thinking that holes it is.
As always, my tiny little brain takes one train of thinking (holes) and makes it more complicated.
But, complicated is the enemy of time and time is finite. I will try to restrain myself......
Stay tuned, hope to have the results by this weekend and will post.
Chip
Accurate 90* (degree) angles
{As I want the two lines to be completely perpendicular, I use a method that does not rely on a square of any type to develop the 90 angle. What I did was use a large compass. I drew the baseline and picked a point on the line where I wanted my centerline. Then using the compass, I swing two arcs from the center point across the baseline, one on either side from the center point. From these two points, I increase the length (as far open as I can make the compass) and swing an arc from each. A line drawn from the original center point through the intersection of the two arcs is perfectly perpendicular to the baseline. I do all that and then check it with a square. What does that say about me?}
Chip --
Another "trick" to get a very accurate 90* angle is used by a lot of contractors/carpenters-- a triangle with sides in a ratio of 3:4:5 (leg1:leg2:hypotenuse) has an exact 90* angle between leg1 & leg2. [ref. the Pythagorean Theorem ++> (x^2 + y^2) = z^2, where 3,4 & 5 are the smallest integer values satisfying the equation).] This approach can be particularly handy at the edge of material (e.g., a sheet of plywood or aluminum) to make or verify a 90* between the edges of the sheet. Also works to verify accuracy of a carpenter's square!
Lee Johnson
Near Taos, NM
Lee,
Years (eons?) ago I earned my way through college by working as a framing carpenter. We use the 3-4-5 method a lot not only for sheet goods but also for laying out string lines for excavation and footings.
Once upon a time I also knew how to use the rafter pins on a square. Back when we had to trim actual rafter peaks, birdsmouths and tails.
You sound like a good carpenter and every good carpenter I learned from was very smart.
BTW, a good way to check the squareness of your miter-saw, etc, is to make a 90 cut, the flip one of the pieces front to back and align along a strait edge. If the saw is actually square the two pieces will butt with no gaps. If not, the pieces will touch along one edge and have a gap at the other one.
I still enjoy woodworking and right now am building a rolling workstand for my sheet metal break. If anyone has any interest I will post pics.
Tanks,
Chip
Chip --
I'm not a carpenter, but an engineer (not a pure theory type, but I do remember some theory, including Pythagorean Theorem!!).
I will follow along with your process on the Lola with great interest as I raced a Bobsy SR5/6 in C sports racing class in the 70s-80s (with 1300cc FVA & later BDH). Trying to get that car back on the track as we write/speak.
Best of luck & maybe we'll meet up on track,
Lee
Well, it's been about a month since my last post.
Things I didn't do:
Get arrested
Leave the country
Go into witness protection
So, no excuse for not posting........
Things I did do:
Had foot surgery
Got the first phase of welding complete on the subframe
Built a mobile stand for my sheet metal break
Went to Road America for the WeatherTech Vintage Challenge.
First, the subframe,
After much thought, I talked to my welder and he agreed to weld it on the fixture as is.
I decided to do the welding process in two phases;
1. Weld in the motor mounts and rear vertical members, also the rosette welds at the bulkhead. This phase was planned to maintain the alignment of the frame off the fixture.
2. Coming up I am fabricating the diagonal braces and a (metal) fixture for the rear bungs. These bungs align with the upper and lower cross members that I have yet to fab. The idea is that the fixture I use to align the bungs then can be used to fab the cross members so the bungs should all align.
Second, Road America. I had a great time and met a lot of old and new friends. The highlight for me was to see Greg Wold's restored T496. As you may recall, Greg is the one that started this entire process. He bought Fred Shilplin's old T496 as a barnfind. Greg and his brother Kermit completely disassembled (drilled out all the rivets) the car, measured it and produced the plans that he and I are working from. Fred won the SCCA National Championship in this car in 1980 or 81.
The car looks terrific and so I am including pictures of it as well.
Hope to post again sooner than last time. Greg's car has me really geared up.
Pretty picture. This kinda reminds me of the chassis that (can't remember his name---the two stroke Kohler engine guy from Wisconsin) uses. He may be a good source for information or parts??
Misc. ramblings from lockdown.
Marty
Marty,
Thanks for the thought about Jeff Miller. He was there (RA) last weekend as well. I have talked to Jeff and he has helped me with parts & advice on the project.
Actually, since I have started posting, a lot of people have been very helpful with advice and leads. Best thing I did was to post on Apexspeed.
Chip
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