Frame straightening

voodoovette

Well-known member
Joined
Dec 5, 2008
Messages
92
Location
Crystal Lake Illinois
I picked up a frame from a 74 vette, very clean, no rust. The driver side lower control arm mount was damaged, moved over about .250". I corrected this by replacing the mount but after a lot of measuring have noticed the drivers side front crossmember, upper and lower control arm mounts raised about .125" to .250". I would like to pull the frame back to original position, should I bring this to a shop or is this small deflection something I could do with a porta power and blocking? any suggestions?:confused2:
 
I guess the question is what end result are you looking for? if its a perfectly straight frame its hard to argue with a frame shop that uses a perfectly flat table and can strap the frame down and bend it and then measure it with real perfection.

many people at the beginning of a body off restoration project take the frame to shop to make sure its nice and straight.

why not price it out and then go from there. with all the alignment issues C3's have, a straight frame would be a great starting point. who knows after they strap it down to the flat plate you may find that there are more issues. and then after its straight then you can weld up the frame and add gussets
 
Thanks for the info bobs77vet. I did check around and when I tell them it is a bare frame, they say they only do complete cars???. I did find one custom shop that specialize in custom and race cars. When I went there of course the frame guy was out of town. They would not give me a ballpark price. I guess I will try back with them next week since they were the only one to say they could do it. Anyone know what to expect in regards to cost to straighten a minor bent frame??
 
You can get it within 1/8" at home - the tools will cost you less than what a shop charges.... If they can't even give you a ballpark price don't waste your time with those guys.....
Just my opinion...... I've been burnt so many times with so called "shops" not wanting to do the work....

Straightening a bare frame should be a piece of cake for any serious shop that has a frame rack.....
 
Thank you MYBAD79.. I have done a lot of measuring and I believe the drivers side front rail and crossmember needs to be pulled down 1/8" to 1/4". When frame is leveled out the drivers side lower control arm mount is 3/16" higher than the pass side, using a bubble level and shims. The frame rail where the steering box mounts is tilted 1/8" off from being vertical. This is measured using a bubble level on the side of the frame rail where the box mounts, pass side looks good. I do know there was minor damage to the drivers side lower control arm mount, bent about 1/4" inward. I suspect the driver side front wheel and suspension had impact causing this damage. Thinking of using a porta power, blocking and anchors in floor to pull the frame back down. Any ideas are welcome.
 
so on my austin healey 3000 bare frame, going back 20+ yrs ago there was a $250 charge for setting it up on the frame table and taking all the measurements and then it was an hourly rate until it was pulled straight.
 
so on my austin healey 3000 bare frame, going back 20+ yrs ago there was a $250 charge for setting it up on the frame table and taking all the measurements and then it was an hourly rate until it was pulled straight.

Where was the work done?? in the DC region or somewhere else???

:twitch:
 
I will give it a try myself, I usually find when I hire someone to do a job, I look at their work and know I could have done a better job. Not to say they all do poor work, but I think it is worth trying myself. I have 30 years working with aircraft, so I won't screw it up. Worst case, I will bring it to the shop if I cant get it to pull correctly.
 
It should work pretty good if you setup the frame on wooden blocks, level it, strap it down to the concrete with wedge anchors.... this oxy/acetylen setup from harborfreight seems like a good deal, if you heat the frame it will make it weaker and easier to bend (straighten).
http://www.harborfreight.com/portable-torch-kit-with-oxygen-and-acetylene-tanks-65818.html

Do you have a welder? It's even easier to make a small cut and re-weld after bending.... adding gussets is a good idea too....
 
my work on the AH3000 frame was done in Northern Va (DC area). i thought they told me they do not heat the frames to pull them they just do it cold.
 
I will try pulling it cold first. may try some heat if not making headway. I do have a Lincoln MIG welder that I am good with. I would think if the frame is anchored down, a 10 ton porta power should me more than enough to move it 3/16". I will go shopping, have a harbor freight near my house, ok for one time use.
 
LOL- I agree, but I avoid Harborfreight if I will need to use the tool often. I will post once I give it a try to provide an update on my success or failure:goodevil:
 
Fame Now Straight

After searching, I found a shop called Custom Classics only 20min from my house. After visiting the shop, I was impressed with their work and the fact they specialize in custom street and race cars. I had originally thought the driver side front spring pocket was high, I was wrong!! the passenger side spring pocket was low. The rest of the frame checked out good per the factory specs. I have attached some pics of my frame on the machine. This is a 74 frame that will be under my 73 vette. The frame was absolutely rust free because someone had it coated many years ago and it sure did work well.
 

Attachments

  • Frame1.jpg
    Frame1.jpg
    26.1 KB · Views: 20
  • Frame2.jpg
    Frame2.jpg
    33.1 KB · Views: 17
  • Frame3.jpg
    Frame3.jpg
    27.2 KB · Views: 14
  • Frame4.jpg
    Frame4.jpg
    26.5 KB · Views: 17
  • Frame5.jpg
    Frame5.jpg
    21.2 KB · Views: 12
More Pics

Here are some more pics of my frame being pulled. The rear section has been modified for the Ford 9" IRS with 934 CV joints.
 

Attachments

  • Frame9.jpg
    Frame9.jpg
    28.6 KB · Views: 22
  • Frame8.jpg
    Frame8.jpg
    26.2 KB · Views: 16
  • Frame7.jpg
    Frame7.jpg
    28.9 KB · Views: 21
  • Frame6.jpg
    Frame6.jpg
    21.6 KB · Views: 12
  • Frame10.jpg
    Frame10.jpg
    32.7 KB · Views: 19
I imagine it's all done now. How much did they end up charging?
 
Not cheap, $1100 to have it laser measured and pushed/pulled into alignment. They were the only ones that I had looked into that I trusted. Most wanted a complete car because when I told them it was a bare frame, they said they could not or did not want to do it. This place is for custom and race cars and is more specialized.They did not even flinch when I told them the frame had been modified at the rear suspension.
 
Top