the BEST DIY rear cross member?

Post by **defdes** » 17 Jan 2007 18:34

Finally got this part essentially finished. I am going to wait to weld it up until I finish the stainless steel swing arm bushings, and can mock it all up on the work bench. I figure then I can get it close to the "sweet spot" and weld in those washers on the toe-in side to get it close to my final wanted settings. Now on to the lathe....

Post by **Mattndew76** » 17 Jan 2007 20:20

Does anyone have the Dimensions for this set up? If so could that person draw up a print?(Basic Print of all parts B4 weld) With that print I could machine a couple of these kits for my manual mill XP check off at work.

Post by **duke** » 17 Jan 2007 23:59

Did you give the lower toe adjusting slot any arc or did you just make it a tad oversize? Looks good, but round those corners off, square corners just makes it look so unprofessional. Also I wonder if you will have enough camber adjustment, those slots don't look that long.

Post by **rnorrish** » 18 Jan 2007 00:09

There's a set of "new" ones being made as we speak. Byron's going to give them a run through when they arrive, and we're going to revise as neccesary. When all is finalised, the CAD drawing I'm sure can be publicised.

Post by **Mattndew76** » 18 Jan 2007 01:55

Great! I could write a program for them on the 3 axis based off the drawings.

Post by **defdes** » 18 Jan 2007 06:49

duke wrote:Did you give the lower toe adjusting slot any arc or did you just make it a tad oversize? Looks good, but round those corners off, square corners just makes it look so unprofessional. Also I wonder if you will have enough camber adjustment, those slots don't look that long.

I filed the slots a bit over size where they needed it, and yeah I am still going to trim the ears back and round everything up. I'll probably make some little butress supports on either side too. As for the camber, I moved the slots up closer to where the sweet spot is for my car, so it should be enough adjustment. I was afraid to remove alot of meat, and those bolt heads take up some space. There is alot of action to fit on 2 tiny plates, I didn't notice till after the fact that Byron cut the top web off of the cross member and had his ears extend up past its overall thickness thereby buying another 3/4" or so.

Post by **Byron510** » 19 Jan 2007 07:01

Yep, the ones I built had the pivot point much higher, and the slot at the bottom was an arc, obviously pivoting around the pivot bolt. I made Dans’ set up (pics on page 2) on a rotary table, but it was very labor intensive.
I should have the new plates back early next week. I'll find a cross member, clean it up, and remove the inboard mounting bracket, then install the new mount. Rich's company is doing the laser/aqua jet cutting as we speak; I'll keep you posted with pics as this progresses.
Byron

zootowndime · Post by **zootowndime** » 19 Jan 2007 12:08

Byron I am sure you will make extras if they come out nice. I am sure other people would like them. I really need a pair. I know that i need to do something with my rear camber and toe issue before april when the first scca is. This setup definatly seems like the best way besides the datsport.

zootowndime · Post by **zootowndime** » 25 Jan 2007 12:08

Any updates on the new brackets Byron? Just curious how they are coming along.

Post by **Byron510** » 25 Jan 2007 12:37

The brackets are coming along. I'm told that they have been cut, but not yet delivered - I'll keep you all posted.
I did do some more skiving at work today; sandblasted the X member that I'm going to use. I also cut out the exhaust pipe hole, and welded in another larger one for bigger exhaust clearance. A new post with pics will be posted later this evening when I get home.
Byron

Post by **rnorrish** » 25 Jan 2007 19:12

they were delivered today, and the two bits are off getting formed. hopefully tomorrow!

Post by **Byron510** » 26 Jan 2007 23:29

So my co-worker, Sean the 1200 guy, really got into my project yesterday. I started on a new rear X member. I won't have time to complete this for my own car this spring - I hope to do it later this summer, but I need to try out the coming adjustable brackets.
Since I was waiting for the inner X member brackets, I thought I'd get started on the rear X member anyways. So into the blast room it went, and a few bags of #6 glass bead later - it looked pretty good.
Next, the exhaust hole is to be modified to fit a larger pipe. I have had this piece of 4" X .062 SS tube kicking around for 4 years waiting for this purpose. I know that I will be eventually turbo charging the Bronze (some distant future dream), and that this system will be a 3" pipe, so this is the justification for the 4" hole in the X member.
Like I said, my co-worker got into the project. I had some conversation saying that using a torch, you can't neatly cut sheet metal - boy he proved me wrong! So after he cut out the old pipe, I prepped the torch cut area for welding and fit, cut the new 4" tube to length and fit it to the X member. Then Sean, with his master welding skills, did a very neat job of tigging the pipe in place.
Byron

Post by **Byron510** » 26 Jan 2007 23:33

a few more...

Post by **Byron510** » 26 Jan 2007 23:52

Last update of the night…
A bunch of us met for dinner tonight - I ate enough sushi that I feel like a lethargic Fraser River pike...
Anyways, Rich brought the freshly cut, and bent, inner brackets. The vertical adjustment slot was not cut, so I'll need to machine it in.
This is very much a beta version, and not yet finished in any way. I will finish machining these ones, figure out the hardware needed to use either stock rubber control arm bushes or spherical bushes. Also I need to know what kind of adjustment this set up will allow (max toe and camber correction). Once this is figured out, and final adjustments made, I will do a run of them, I don't have the whole package figured out yet. I'll keep you all updated as it progresses. I hope to mount these to an X member very soon. There is already one revision, I will probably be changing the thickness of the inner swivel (“C” shaped) part of the mount, as I don't believe it needs to be near this ¼” thickness!
I was pretty impressed with the laser cutting, though.
A big thanks goes out to rnorrish for his time cleaning up the drawings and getting them pushed through his work load.
McShagger offered to be the guinea pig on this project as I just don't have the time at the moment beyond fabbing up the bits. As a team, we'll have a solution very soon.
Here are the pics of the freshly cut pieces.
Byron

Post by **thisismatt** » 26 Jan 2007 23:53

What, no hole saw?