raising spindles on boge struts

[dfink]

I have been reading the available info on raising spindles. I happen to have boge struts so the standard method is out. That leaves cutting the tube method. Does anyone have pictures of this. It appears to be simple enough in theory to cut some off the top and add some to the bottom. The ball joint mount appears to just be welded to the bottom of the tube. Would it be better to cut the bottom halfway up the tube and place someother tube over both or cut right at the bottom and just reweld the mount for the ball joint. This is not an area you want to fail......Also welding such tubing. I am much better at welding using acetylene torch than mig. Any forseen problems rewelding the tube with a torch rather than a mig.

Pitfalls........
Success stories.......

Fill me in before I do my usual and start something I shouldn't have.

[Walt Fricke]

DF

I can speak to dealing with the top of the tube, where you will want to cut out a section equal to how far up you want to raise the spindle. Cut maybe two inches down, so you have the threaded part in good shape and able to function when welded back on.

On your bench grinder bevel the outer edges of the tubes to be rewelded. That way you are pretty much guaranteed to have good penetration. I did my welding with a cheap low power MIG and I am not all that good at welding. It has held up just fine for years on my track car, even after I ground off all of the protruding weld (so I could slide a tubular spring perch over it). The stresses up at the top of the strut, of course, aren't as large as they are down at the bottom.

Use a chop saw or some other method of insuring that both your cuts are dead straight and at a true right angle.

To make sure the tubes lined up for welding I took a muffler tubing expander and used it to hold the two pieces in alignment until I could lay down some tack welds. Then I removed it so it wouldn't melt - it was a cheap piece, and never worked well expanding things. Worked perfectly here, though.

Someone with more welding skills will have to opine on MIG vs acetylene, though I'd not think gas welding would be bad. The tube is stout stuff, not sheet metal.

I like your idea about sleeving at the bottom. You could rosette weld as well do circumferential welds. If you can't get tubing with just the right ID, perhaps you could get thicker wall tubing and increase its ID on a lathe.

Walt Fricke

[dfink]

Well I pulled everything apart today mostly because I didn't want to take the entire front suspension down as a unit again. You can take it all off at once but since I wanted to check the struts anyhow I took them off. This work all ties into replacing the front susension pan which was rusted out. I put the susension back in during weld up to make sure it all fit well so now it all has to come back off to paint the pan and apply seam sealer.

Anyhow I probably won't attempt this project after all. In all the discussions of this procedure I just barely remember someone mentioning wheel size. Well turns out that if you are using 15" wheels the amount you can move is hardly worth the effort. With 16" wheels it looks like 30mm id doable. With 15" maybe 10-15mm not really enough I don't think for the effort. It was however a good oportunity to check the ball joints. Had a heck of a time with the right side ball joint till I figured out I could just lift the strut off the ball joint. They came apart very easily and appear to be in pretty good shape so I don't think I will replace them at this point.
Back on subject I think it might be difficult to bore out the spindle and move it up the tube. Anyhow for future reference you can probably do this with 16" wheels or larger. If you want 15" Wheels you are pretty much stuck with what you have.

[Walt Fricke]

I recall 19mm as being the amount the RSR (Bilstein) strut spindles were raised for use on 15" rims.

For my '68 based track car, I just had a 19mm spacer made to raise the strut, and then cut a similar amount out of the top. Easy. And well worth it for a track car running 15" rims.

I think the way to go with Boge struts would not involve boring out the spindle. I think it would involve cutting off the ball joint attachment, and using that, the spindle, and perhaps the threaded top of the strut, along with some brand new tubing, to make a new strut.

Or do the double cut, etc.

All of which suggests maybe changing to Bilsteins, which are more easily modified, might be the best way to go. If one wants to go.

[dad911]

Tread carefully. I have no experience with boge struts, but had a modified bilstein fail at mid-ohio. It was not fun. I switched to RSR bilsteins, which are already modified. They work with 15" wheels.

[Walt Fricke]

dad

How/where on the strut did it fail? Were the RSR style gussets added when it was modified?

I had the whole spindle break on my old struts. First time it was half way out on the spindle (brake rotor and caliper held wheel sort of in place). Second time the entire forging broke off, and I watched a wheel, with hub and brakes attached, roll off ahead of me. I was lucky then also. These are now heavily reinforced.

Walt Fricke

[dad911]

As I recall, tube broke above the spindle where it was welded back on. It was welded all the way around.