Straighting a gold tub

[myfordcnc]

Any body have experience doing this? I'm getting going on doing some DIY anodizing. As I was prepping the tub (put it on a reference plate) I noticed that it is seriously out of flat. About 3/8" over the length if I hold one end down.

I read here that early on they had to straighten them when they came back from the stamping operation. They used a buck to straighten them.

Short of making a buck what else could I use. I was thinking of doing some thing like they do for cylinder heads. But I don't know. Any suggestions or is this how they are suppose to be. Are they preloaded like that on purpose? Like tractor trailer trailers?

[justinspeed79]

I have a highly technical procedure that is hard to explain, but I'll try. In one hand hold the front of the chassis, in the other hold the back of the chassis, brace the middle of the chassis against you're knee, pull until straight. Repeat as needed. This can be done on a bare chassis, or a complete chassis.hope this helps.

[GoMachV]

That's pretty much my method too use a straightedge to confirm and your good to go until the next impact with a curb or harsh landing

[myfordcnc]

I have a highly technical procedure that is hard to explain, but I'll try. In one hand hold the front of the chassis, in the other hold the back of the chassis, brace the middle of the chassis against you're knee, pull until straight. Repeat as needed. This can be done on a bare chassis, or a complete chassis.hope this helps.

So were do i put my hands exactly? One hand on the rear the other on the front. left on front and right on rear?. Or right on front and left on rear? Do i need to take into account the earths bi axial tangential axis or just forgo that and rely on the magnetic diffracting modular pulse signals. Perhaps the application of MFC's principle could resolve my issue.Though that is doubtful as that idea has been debunked since the advent of that thing we shall not name here. Wow completely forgot were the knee goes. Never mind I think I know.

I was asking because the bracing of the tub makes that approach not very precise. I want to be able to impart a regular surface before anodizing. Plus just wanted to know if it was normal or a result of abuse or maybe was one of the early tubs that they might not have straightened.

[GoMachV]

They were just a real easy chassis to bend. They should be straight. It was common practice for us to bend the chassis back between races. Just make sure it doesn't have twist to it and your golden!

[myfordcnc]

They were just a real easy chassis to bend. They should be straight. It was common practice for us to bend the chassis back between races. Just make sure it doesn't have twist to it and your golden!

Thanks G5.

[jwscab]

yeah, it's just a matter of getting the bend back to straighten it up. You will have to bend is slightly past straight to take the bend out, I usually put the chassis on the ground supported by 1/2" or wood on the side rails, upside down, and use the foot method to apply 200lbs or so on the chassis, little at a time until it's straight. Sometimes you have to tweak the side rails in or out a bit. I have noticed on some really bent ones I have to put a brace between the nose brace tune holes and rear bulkhead holes to keep the side rails straight, and once you do that, you can stretch them into submission. otherwise, they flex in or out and don't straighten.

[scr8p]

BFH

[SFC K]

BFH

What is that?

[GoMachV]

BFH

[klavy69]

circus%20hammer%20_L.jpg (44.69 KiB) Viewed 1043 times

circus%20hammer%20_L.jpg (44.69 KiB) Viewed 1043 times

that should do it

Todd

[RedScampi]

No, no, no! This:

...actually I put a block of wood on the inside and outside to protect the finish, then put one end of the chassis in my bench vise. Then I can apply appropriate pressure on the other end. It's a bit springy so you have to pull just a tad farther than straight, and it'll spring back. I reposition the chassis in the vise several times usually. Take your time and you can get good results.