Getting close to welding in rear crossmember for 32 ford frame. Using 2x2x5/16 square tubing. Rails are currently in jig and boxing plates tacked in. I want to weld rear crossmember in before welding boxing plates up. Should I anlge crossmember to account for final rake of chassis. I would like to end up with about 4deg of rake when comlete. Not sure if I should tilt crossmember or weld in level to frame in jig.
Depends on what spring you are using or if using coil overs. Both are normally set in with the spring/coil overs on place and the rear axle rotated to provide the proper driveline angle (+/-) 3 degrees. The mounting points of each should be parallel to each other so the shackles/bolts will not bind.
This like which came first the chicken or the egg.. spell out what type of suspension set up you are going to run. That will determine some discussion on the position of the cross member. Remember if you are running a cross spring the longitudinal angle position of the axle spring hanger determines the angle of the cross member as the spring must not operate in a bind or vise versa. If you are using coil overs you have a little wiggle room but not much based upon the style ends the shocks have.
Lots of pic's also help others to know exactly what you are doing. One pic will save you 1,000 words of explanation or so they say...
Sorry guys, Im running a 40 ford front transverse spring. Making my own spring hangers and using pete and jakes ladderbar setup. I have found pages online describing front crossmember setup in relation to rake but nothing on rear crossmember. Thanks for helping out.
Dick, regarding your post. I will assume if I weld in crossmember level to jig, I can then adjust spring hanger angle to prevent bind. If thats what your saying I understand. Is that the way you like to see them done?
There's a lot that comes into this. Just start at the bottom up. #1 - rear axle center line must be maintained. 1a - set ladder bar threaded adjustment centered so you'll have some adjustment when finished. I like to set the bottom bar level. #2 drive line angles ( pinion angle) need to be maintained. #3 spring hanger and spring eyes need to be parallel and not bind. #4 spring should sit flat on crossmember. But you can use some wedged shims if you need a little help, or an angle milled spring mounting plate. If you can rotate the axle in the spring hangers and ladder bar brackets because they arent welded yet, you can easily satisfy all of those, especially if you'll be making your own spring hangers. If you could not then the crossmember location and angle would be determined by the spring pad after the axle is rotated into the correct position. If you don't watch every step you can really bind the shackles or throw the axle front to back 1/2" out of wack.
31 vic, thanks for quick response. Im hoping thier is more than 1 way to skin this cat. Im so worried about warping while welding up boxing plates I want to weld in rear crossmember while frame is still in jig. This is my 1st attempt at this style build and while im confident in what i have done so far im not sure what i can get away with and what not. So I am choosing to weld up crossmembers and boxing plates in jig and then remove frame from jig, set a desired ride hight and continue on the build. I currently have frame leveled in jig with 10 degrees added in front crossmember and 3 degrees in rear crossmember. Also im double boxing area around rear c notch and im welding rear crossmember to both boxing plates for extra reinforcement.
You seem to be headed in the right direction. Tack everything then step back, measure again, THINK, and then weld it. Lots of good advice on here so use what you need and post a photo of the outcome. Good luck.
You want to mount the spring(crossmember) so the spring makes a 90* angle to a line from the spring mount on the axle to the rear end forward suspension pivot point, This would be to minimize binding as the rear swings and moves forward during the movement. Henry was a genius in that he mounted his springs in open channel crossmembers so the crossmembers could twist a little to accommodate the movement.You need to figure how much the spring will compress with load or just set the ride heigth and assume you will get the spring to hold the car there.
you are using a front spring. did you take any leafs out? im doin this same setup but trying to research how what others have done to soften it up a bit
I will be using a 40 ford front spring. The spring I have is off a pickup so it may be different from yours. I am going to try it because i already have it. If I run into problems Ill just order new one. There is a lot of info on this subject, you just need to search online to find it.
I just set mine up with a 40 front spring out back, made my own hangers too. My set up might be good for a few things or references but my rear frame sweeps up higher and my crossmember has a dip. Used a 40 rear crossmember that was narrowed and made flatter so everything fit where I wanted at ride height. Also, if your differential has much of a bump to it, you'll have to adjust the crossmember back and make the hangers match the CL axle to the CL spring or the diff will rub the crossmember or spring bolts. Here's a step by step on how I did mine. • Chassis at ride height. Lots of BS measuring, math, and mockups. • rear axle set at height, and centered, and drive line established. This also required the same BS measuring, math, and mockups. • made a fixture to hold the rear end here but let it rotate. Couple tubes and channel scraps. • spread or collapse spring to proper distance Eye to eye. You can use a spreader if the eyes aren't reversed or a large quality clamp and a tube in the arch. You'll need to make a doohickey to ride the bolt and keep the clamp centered. You could also disassemble the spring pack and use just the main leaf and a spacer to simulate the spring pack. • figure out how far behind the axle center line you need to be, how far above or below the center line you need to be with spring at 90* to crossmember and the rake of the crossmember you decide to go with. I put my spring 90* to the ground and 4* into my crossmember. •fabricate your hangers accordingly. • get your spring into the shackles and hangers with hangers on rear end & with a 40 ford front car spring the hangers are at 42-1/2 C/C. • start fitting this up, and double chech with more BS measuring and math. • rotate your axle to the proper driveline angles and figure out how to keep it there. Tack your hanger just enough to keep them from flopping around and just incase an easy place to grind out your tack. •hang your ladder bar brackets, P&J are set for 38.5 ish but it will vary because of the angle they cross the axle at and you want the blots to go thru smooth. • figure your crossmember location based on the info you choose to use for the bars. •tack those the same way. Just enough to keep them from flopping and easy to cut out. • double check everything. Driveshaft clearance, bars to floor interference, that you have some adjustment on the bars, your wheels will be where you want, your ride height is not too high!!! ( low is easy to correct) the blots are finger free to move. • happy tack it up better and proceed. There's other ways to get this but this full mockup eliminates any potential problems and gets you right where you want to be. The hard part is knowing where you want to be.
Ii bought a compltete front suspension out of a 41 ford truck a guy was putting a mustang II suspension in. I split the wishbone amd used the brakes for front. Now I got the rear of my model a mocked up. Ladder bars. Plates. And spring behind axle hangers. Lookin at this spring to use. Commonly done but lookin for a good tech article step by step if I need to remove leafs Posted using the Full Custom H.A.M.B. App!
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