Mid 90's Van Diemen Frame Steel

[BeerBudgetRacing]

I am considering a few changes to make some additional driver room in my 94 FC.

I know these years the frame was brazed with Nickel Bronze material.

Does anyone know what kind of steel was used? or should be used?

[S Lathrop]

Stay with mild steel. That is the closest material to what your frame is built with. I would stay with the welding process the frame is built with.

I was taught that one should not braze 4130 alloy steel. 4103 can be gas welded or TIG welded.

My own experience with MIG welding has not been good.

[chrisw52]

what about for repairs on existing tubes? I am going to patch up some rivet holes in the frame, nothing structural.

[S Lathrop]

what about for repairs on existing tubes? I am going to patch up some rivet holes in the frame, nothing structural.

Those rivet holes are on flat surfaces?. Welding the holes will warp the tube and surface. I doubt that is what you want to do.

On my cars, I add rivet strips to the side of the lower frame rail tubes to double the rivet and bonding area. I am very careful to use strips that are the same thickness as the tubes they are welded to.

I most cases there is a single row of rivets down the center of the tubes. I just leave the holes and use a double row of rivets staggered on either side of the center of the tube.

[Buc01]

1018 steel.

AS

[chrisw52]

Those rivet holes are on flat surfaces?. Welding the holes will warp the tube and surface. I doubt that is what you want to do.

yes, this repair work would be on the lower frame rail. Instead of using a rivet strip like you're suggesting, someone had drilled the frame rail directly. So at this point, the side of the frame rail is almost what you would expect the floor pan edge of the frame rail to look like, swiss cheese. I wouldn't mind so much if it were for the floor pan, because the bonding agent would seal that surface. My biggest concern is corrosion protection here.

My plan was to use a TIG welder and just fill the holes as if I were doing a plug weld. Would that warp the tube?

On my cars, I add rivet strips to the side of the lower frame rail tubes to double the rivet and bonding area. I am very careful to use strips that are the same thickness as the tubes they are welded to.

I most cases there is a single row of rivets down the center of the tubes. I just leave the holes and use a double row of rivets staggered on either side of the center of the tube.

I really like that idea. Will probably do the same while fixing this problem.

[Earley Motorsports]

On my frame I just mig welded the holes and ground them off. The mig was quick and no warp on an eighth inch hole.

[BeerBudgetRacing]

On my frame I just mig welded the holes and ground them off. The mig was quick and no warp on an eighth inch hole.

As long as you jump around to let the spot cool before doing the one next to it, correct? Heat up 2 or 3 in a row and I suspect you'd get warping...

[S Lathrop]

How big are the holes? Are their cracks prorogating from the holes? I would recommend leaving the holes.

My frame rails are .049 thick. Welding and grinding gives me heart ache. I had a customer TIG weld the rivet holes on the lower frame rails and in my estimation the frame was trash as is and needed the bottom frame rails replaced.

The bond of the belly pan to the bottom of the frame is so critical to good frame strength, any warping of the surface of the frame rails compromises the bond and/or the durability of that bond.

I am only speaking for Citations. A car with .060 wall lower rails, welding may be just fine.

[chrisw52]

the holes are 5/16 for the most part and there are some 1/8 holes too. You asked if there was any sign of cracking; there is none that I can detect.

the frame rails in question have already been bonded to the floor pan so I am relying on that bond to keep any warping to a minimum. I am planning on using the technique that Earley Motorsports suggested, and stitching my way down the frame rail alternating every 2nd or 3rd hole to keep heating at a minimum.

[S Lathrop]

the holes are 5/16 for the most part and there are some 1/8 holes too. You asked if there was any sign of cracking; there is none that I can detect.

5/16? 3/16 is a standard rivet size. Why not just reuse the existing holes?

[chrisw52]

5/16? 3/16 is a standard rivet size. Why not just reuse the existing holes?

my bad... I meant 3/16. these holes were only used for mounting body work which I don't think need the structural integrity of a rivet every ~1.5" to secure to the frame.

[924RACR]

On my cars, I add rivet strips to the side of the lower frame rail tubes to double the rivet and bonding area. I am very careful to use strips that are the same thickness as the tubes they are welded to.

Really liking this idea... my FF-based car has all the pinholes directly into the frame rail bottom, sounds like this will be a nice improvement/upgrade next time I mess with the floorpan...

[Rick Iverson]

I received the exact chassis material nomenclature as well as welding rod (Sifbronze) description, heat etc from Van Diemen UK in the late 1990s. I'll try and locate and post it tomorrow.

V/r

Iverson

[Rick Kirchner]

get the Sifbronze and take it to Victor Herfeldter in Riverside or Wayne Hannabury in Ridgecrest. Art smith also has a line on a great frame welder down in the LA basin - he's modified several frames for Art.

[Rick Iverson]

Chassis is made from: "4130 tube heat No: 37590 Pacific smls condition N."

The correct rod to use is: "Nickel Bronze 2mm Diameter Sifbronze 101."

Steels	Diameter in mm	Carton size kg	Melting point degrees C	Ultimate tensile strength N/mm2	Hardness BHN	Process	Typical percentage composition
SIFBRONZE No.101 A special brazing rod containing specific additions of Manganese and Tin, giving it free flowing characteristics. It is particularly suitable for use with 'gas flux'	1.5 2.0 2.5 3. 0	1.0 2.5 7.5	870-890	460	130	BRAZING	60 Cu, 0.2 Mn, 0.1 Si, 0.1 Sn, Bal Zn

I have a dozen or so rods, but unfortunately they are in Minnesota. Hope this helps.

V/r

Iverson

[ewcmr2]

I converted a 94 FC to FF/Honda. Rear half of chassis needed some mods to fit Honda engine in place. I brazed (Allstate filler?, bought a small quantity from someone on Apexspeed) the new 4130 tubes to existing nodes, TIG welded all the new nodes.
Three years later it's all still in one piece.

[BeerBudgetRacing]

Chassis is made from: "4130 tube heat No: 37590 Pacific smls condition N."

The correct rod to use is: "Nickel Bronze 2mm Diameter Sifbronze 101."

Steels	Diameter in mm	Carton size kg	Melting point degrees C	Ultimate tensile strength N/mm2	Hardness BHN	Process	Typical percentage composition
SIFBRONZE No.101 A special brazing rod containing specific additions of Manganese and Tin, giving it free flowing characteristics. It is particularly suitable for use with 'gas flux'	1.5 2.0 2.5 3. 0	1.0 2.5 7.5	870-890	460	130	BRAZING	60 Cu, 0.2 Mn, 0.1 Si, 0.1 Sn, Bal Zn

I have a dozen or so rods, but unfortunately they are in Minnesota. Hope this helps.

V/r

Iverson

Thanks for the great info Rick.

I found the rods in the UK. It's obvious shipping is the big hangup.....

https://www.weldequip.com/sifbronze-brazing-rods.htm

[DanW]

Thanks for the great info Rick.

I found the rods in the UK. It's obvious shipping is the big hangup.....

https://www.weldequip.com/sifbronze-brazing-rods.htm

Check with Keith Averill at Averill Racing Stuff. He may have some.

[Rick Iverson]

Don't forget a container of flux.

Thanks for the great info Rick.

I found the rods in the UK. It's obvious shipping is the big hangup.....

https://www.weldequip.com/sifbronze-brazing-rods.htm

[BeerBudgetRacing]

Thanks for the reminder.....

I spoke with Brad @ Primus and he can get the SIF Bronze from his UK supplier.

Big question is: How much do I need? Probably 2 dozen joints by the time it's done

[Rick Iverson]

Brad will do you right.

I'd buy at least one (1) pound of rods, but......

I bought, say sixty rods, and one pound of flux in a pint container. Divided it up into bundles of 5 rods and 1.33 ounces of flux. Divided 12 into the total cost of the sifbronze so everyone, to include myself, paid equally. Sold it all, but was stiffed twice (2 eff'in times) by the same guy.

Just a thought.

V/r

Iverson

Thanks for the reminder.....

I spoke with Brad @ Primus and he can get the SIF Bronze from his UK supplier.

Big question is: How much do I need? Probably 2 dozen joints by the time it's done

[S Lathrop]

Thanks for the reminder.....

I spoke with Brad @ Primus and he can get the SIF Bronze from his UK supplier.

Big question is: How much do I need? Probably 2 dozen joints by the time it's done

A pound of rod should be way more than enough.

[Jerry Kehoe]

While you can braze these together with the flux the right way to end up with joints that look like the originals is to use a Jet fluxer which mixes the flux with the gas. These units are around and if you plan on ever continuing doing this it is well worth the expense of the bottle and hardware. The visibility using the dip flux when using the rod is poor whereas the fluxer allows visibility much like TIG welding and you can see the rod and joint far better.

[BeerBudgetRacing]

I'm currently talking with a local bicycle frame builder. He knew exactly what SIFBronze was and has used it in the past in restoring older frames...

I've seen some of his work, compound curves, etc. so I think my mods will be pretty straight forward.

Would be interesting to see if he uses jet fluxer...

[Unbalanced Engineering]

Does anyone have contact info for Victor Herfeldter?

Got it. Thanks Jack.


Back to the drawing board.... After asking me to wait for a month, now Victor isn't responding.... So be aware anyone who might want to use him....

Thanks,
Jason

[Jerry Kehoe]

Most of the bicycle builders use the rod that flows rather than beads as it is available in both forms. You want the beading rod if you are working on race car frames and suspension.

[BruceRace]

Relive the edges a bit........fill with "J-B Weld" and sand smooth.....if it's cosmetic stuff!!!!!

[Comp89]

I am considering a few changes to make some additional driver room in my 94 FC.

I know these years the frame was brazed with Nickel Bronze material.

Does anyone know what kind of steel was used? or should be used?

Here the reply that I got from the man himself

"All VD Chassis were built with either T 45 or 4130 both are a chrome moly material
Kind regards.

Ralph "

[swiftdrivr]

If it is just to keep out water, why not keep it simple and use JB weld? That won't warp anything.

[Unbalanced Engineering]

Uh, joining chassis tubes with JB weld???? NO....

[swiftdrivr]

I thought he was trying to fill rivet holes, not join tubes

[Rick Kirchner]

multiple discussions in this thread. the bottom is not related to the top.

[John Nesbitt]

Thanks for the great info Rick.

I found the rods in the UK. It's obvious shipping is the big hangup.....

https://www.weldequip.com/sifbronze-brazing-rods.htm

If all else fails, it is available on Amazon (and eBay).

[swiftdrivr]

multiple discussions in this thread. the bottom is not related to the top.

The voices in my head do that sometimes too. It's so confusing

[BeerBudgetRacing]

The voices in my head do that sometimes too. It's so confusing

Its the arguing that's the worst.

[BeerBudgetRacing]

multiple discussions in this thread. the bottom is not related to the top.

This thread is from 2017. 2 years ago. Modifications done 18 months ago....

[TedV]

Its the arguing that's the worst.

Loosing the argument is the absolute worst.

[romanroman]

1

[Jerry Kehoe]

Some time ago this phone number was on the site to purchase nickel/silver, bronze rod here in the US. The number I have is 440 365 1941 which I think is in Ohio. Obviously this would save shipping from the UK>