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Lower A-Frame Rebuild

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N

NW_SpriteGuy

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After many attempts, I finally persuaded my outer fulcrum pin to leave the comfort of its home for the past 36 years. It was well entrenched and didn't want to leave peacefully. No amount of coaxing could entice it to leave and it eventially caused quite an ugly scene. It wasn't a very pretty site, and it wasn't for the faint hearted with weak stomachs because it was actually pretty mesy. However, we must stay the course, and now the rebuilding must take place. My question is this, has anyone ever rebuilt a lower A-frame unit before by removing and replacing the outer fulcrum threaded sleeves. I'm assuming these are just brazed into the A-frame and could be replaced fairly easily. I've priced up replacement lower A-frames and they seem to run about $110-$150. I was just interested in seeing if I could save a few bucks by just replacing the threaded fulcrum sleeves myself by brazing in new ones myself (brazing is a skill I already know how to do). Has anyone done this before and have any comments Pros/Cons. I'm concerned about alignment problems. Also, if someone has a good source for the complete unit at a decent price, maybe I should just stick to buying 'em.
 
I've been very tempted to do that same thing, but I've always been able to scare up a servicable A-frame, so I haven't done it.
In all honesty, I'd like to do something to get rid of the threaded pin and replace it with something that can provide camber adjustment. I may play around with this idea when the snow comes.
If you're doing any work on a Spridget A-frame watch for cracks...even small ones. I've seen lots of cracked A-frames over the years.
 
aeronca65t,
If you come up with a camber adjustment system please let me know... otherwise, it's pretty straight forward and set.

I did find an alternative source however. It seems that Apple Hydraulics, located on the East Coast, has rebuilt lower A-Frames ready for immediate shipment for $75.00 each. That's with a core exchange, otherwise, add an additional $45 core charge. If anyone's interested, they also have rebuilt front shocks available for a decent price.

-Don
 
Don, and Nial.
Why anyone would mess with attempting to rebuild a 36 year old control arm is beyond me, but whatever floats your boat, I guess.
Regarding camber adjustment, three points worth mentioning.
Shims under the front shocks. If my memory is right, (and that is questionable at times), a 1/4" spacer under the shock gives you about a one degree negative camber change. Assuming you are still running lever shocks, that is.
Don't be tempted to buy the shocks with the ends of the lever cut off, and the levers drilled and threaded for a Heim joint. The loading on the joint is all wrong, and they can, and do fail.
Eccentric bushings in the control arm pivots work well. They're a bit of a fiddle to set, but give you precise control over the camber adjustment.
Just my two pfennigs worth.
Nial, didja finish the body work yet? Ouch!
Jeff
 
Jeff,
I agree with you... don't really want to mess with it myself (rebuilding A-Frames). Would rather just buy it out... but for a good price. I just don't like having to pay full list price for these things, and figure everything's open to negotiation. Sometimes, it's a matter of finding the right person (or firm), that's willing to negotiate.
smile.gif


-Don
 
hey fellas,
i did what sprite guy is suggesting. i made cups on the cnc lathe at work(still have the progms) as i recall one thread was kinda an oddball. other than that it was a fairly straight foward job. i had a buddy do the torch work.i used good material also 4140. timing the threaded sleves is no biggie. i have had no problems with that side,at all. the other side i purchased from that lady in Ks. That side i believe has a very worn cup. i am not sure why yet, maybe it was made from recycled beer cans? not sure as of yet.

Apple hyd has a thumbs up from me. i purshased a set of front shocks from them and they have not leaked a drop. Peter is the guy to deal with. had i known abot Apple , i would have purshased my lowere a-frame from them in stead of from vicki. the one nice thing the purchased a-frame had was grease nipples on both sides. if i were to make the cups again i would add this feature.

Bugeye mentioned the 1/4 shim under the shock deal before to me. do you folks think this would help out a street car?

mark

[ 11-04-2003: Message edited by: SilentUnicorn ]</p>
 
Actually, I agree with Jeff...messing with an old A-arm may be more trouble than it's worth (but having all this junk around, it's still fun to experiment). One of the other Spridget racers in our club is building a prototype setup using Spit ball joints and hub carrier...I don't know if I'd bother to go that far.

Presently, I'm running about 3 degrees negative camber via slotted shock bodies. I put a filler piece in the slotted hole (to keep the shock from shifting around).....for a little extra insurance, I also glue the shock to the frame using PL200 adhesive. The shock valves are removed and the units serve only as an upper arm (I'm running tube shocks all around....OK, technically, they're tube "dampers").

An alternate is the eccentric trunions available from some suppliers.

Apple Hydraulics may have a good reputation with their A-arms...I have no experience with them: but they get very mixed reviews on their lever shock rebuilds. Two of my local shops won't buy from them anymore, and some of the folks here at BCF have complained about them too (but to be fair, the guys above seem happy with them). If I needed a set, I'd buy new ones. Lever shocks are fine for the street (I have them in my '66 streetster), but they seem to fade too much for racing. Only one of our 5 Sprite racers runs lever shocks....and the only way he manages to keep them alive is by running ridiculously super-stiff springs.

Jeff: Body work is progressing...if I can get out of raking leaves this weekend, I should be almost done.

Here's some great ways to consume money:

Excellent Spridget stuff from Peter May:

https://www.petermayengineering.co.uk/specialist%20prods.htm#SP1.29

Frontline is also good:

https://www.mgcars.org.uk/frontline/frntsus.htm

Speedwell has a good rep too (they mention the "shock-arm cutting" that Jeff talked about):

https://www.speedwellengineering.com/frontsusp.html

To see some neat "kitted" Spridgets, go to the FISC website:

https://www.fisc-racing.com/index2.html
 
For Miss Agatha I just got complete new ones. Came from England and were made on the original templets. Etc etc
 
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