Question for those of you running poly bushings on your cars... (JWG, Mance, and others)
#21
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the ones that are parallel or the ones perpendicular to the ends of the insert?
I'm assuming you mean the perpendicular ones... what if I were to put it at, say, a 30* angle? That way the ones parallel with the ends go with the grain, and the angled one isn't as abrupt...
Obviously, if I could do it this way it would enable me to do this w/o a CNC lathe... won't be as slick and nice as yours, but almost as functional I'd think.
Obviously, if I could do it this way it would enable me to do this w/o a CNC lathe... won't be as slick and nice as yours, but almost as functional I'd think.
#22
nowhere close or even near "almost as functional". You'd be better off running annular rings...
without connecting them. Least that method is about 20-25% as effective. Once you make a grid you reduce surface/swept area and accelerate bushing degradation due to surface tension being DRAMATICALLY reduced. Counter-productive.
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gotcha... well that sounds good enough for me...
I'll see what I can do here. BTW, if you don't mind sharing, about how deep of a groove did you cut when doing the helix?
Also, got the CA bushings installed last night... put a HEFTY amount of anti-seize on the outside portion that's in contact w/ the CA, and will do an equal amount on the inside as well as all "exposed" surfaces when I install them...
Thanks for all the tips thus far, Mance... I appreciate it!
Also, got the CA bushings installed last night... put a HEFTY amount of anti-seize on the outside portion that's in contact w/ the CA, and will do an equal amount on the inside as well as all "exposed" surfaces when I install them...
Thanks for all the tips thus far, Mance... I appreciate it!
#24
.020" depth (.010" per side) is about perfect but DO NOT use a "V" cut. You MUST use a ball-nose...
or radiused tool for cutting the rings or risk snapping the bushing internally under loads. .0625" (1/16") cutting tool width grooves on .1875" centers is a good place to start. A "V-cut" annular ring wont live 5 minutes once installed as it will break/shear at the sharp point due to the stress riser where the v-lines intersect and a flat/angular "U" cut will have 2 stress risers (1 at each corner) for the same reasons. Radiused rings are the "only" option worth considering.
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makes complete sense...
learned that stuff in school with the stress analysis calculations, etc. Sharp radius promotes cracking and what not, and is a peak for stress as well.
Now when you say .01" per side, are you saying that for the Bushing (cut .01" into that) and then for the SS guide (cut .01" into that), so in total it's .02" deep?
Thanks for the info! Now the fun part is seeing what kind of tooling we have with the machine at the factory. I'll check it out over easter and see what I find
Now when you say .01" per side, are you saying that for the Bushing (cut .01" into that) and then for the SS guide (cut .01" into that), so in total it's .02" deep?
Thanks for the info! Now the fun part is seeing what kind of tooling we have with the machine at the factory. I'll check it out over easter and see what I find
#26
correct on the depth of cut info. But I would avoid even attempting to cut rings...
in the SS bushing. If you cant do a helix do nothing at all either to the acetyl bushing ID or the SS bushing O.D. And plan on a tight .001"-.002" under-size fit of the acetyl bore I.D. to SS bushing O.D. Far better than risking anything else in that area. May squeak, may not but its the lesser of ALL other evils!
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ok, so you're saying to undersize the hole on the acetron
so that it's a slight interference fit? Wouldn't I want a little extra play in there? Or is that to prevent water from getting in there and such?
the ones I just put on my car have about a .002" (iirc) oversize b/n the ss insert 9.733" OD) and the delrin bushing (.735" iirc). Of course, that could possibly be squished down a little bit after I pressed them into the CA, but that's what my calipers told me when I did a quick once through with measurements...
the ones I just put on my car have about a .002" (iirc) oversize b/n the ss insert 9.733" OD) and the delrin bushing (.735" iirc). Of course, that could possibly be squished down a little bit after I pressed them into the CA, but that's what my calipers told me when I did a quick once through with measurements...