Sloppy Skis - A solution

JDDDeere · Post by **JDDDeere** » Thu Jan 24, 2008 1:21 pm

Thought I'd start a new post (same topic).

Just to review.. I had over 3 inches of free play at the end of both my skis and the sled (a Sprint) was steering very unpredictably (severe darting). There was some wear on the bolts, saddle holes and pivot bushing (but mostly the pivot bushing). New 3/8 bolts were the easiest to find/replace (following the advice by others regarding length and torque), however, the other parts were evasive until... Todd (aka JDT) [thanks for you help by the way] steered me in the direction of the McMaster-Carr website (www.mcmaster.com). So, while I assume some of you are familiar with this site, I wanted to share the following details with those that might not be, as I think several of the parts I am replacing are common to other sleds (such as cyclone, LF, Trialfires, Sport and Snowfires).

It also bears worth mentioning that when I dropped the spindles, I had no lower bushing What-So-Ever (yikes)

:o ! which probably contributed 90% to my woes!

To summarize, from McMAster I order the following:

1 package (of 5) Flanged Nylon bushing for the ski spindle (these are 3/4 ID, 7/8 OD, 1 1/4 inch long) these may be 3/8 of an inch longer than stock, but should definitely be usable (Part Number 6338K472) and cost for package was $7.60. I assume they will slide-in a bit deeper, but could also be trimmed if necessary.

As a back up, I also got a pair of "oil impregnated bronze" shoulder bushing/sleeves, same ID and OD as above but are only 3/4 inches long. These are $1.51 cents per bushing and should fit right in.

For the Pivot bushing (used in the bottom of the spindle between the saddle), (Todd and I) found the necessary OD (5/8) and ID (3/8); however only in a 1-inch-long length (need 1 and 15/16)... So I ended up getting two per side, and will grind off some of the excess so that is just a smidge longer than the width of the spindle which is 1 3/4 inches. The part number for these is 6381K606, $2.25 per bushing made from Alloy 932 Bronze (I got 4). These are also available in SAE Bronze for $1.67/bushing. (got two of these just for back-up!)

So... I hope this helps somebody. Will report back in 2 - 3 days with the outcome.

Dan

ChickenRat · Post by **ChickenRat** » Thu Jan 24, 2008 1:30 pm

Yeah Dan,

Keep us posted on this as this is very good info to file away.

Thanks,

Robb

400brian · Post by **400brian** » Thu Jan 24, 2008 4:34 pm

The steel tubing of the size needed for the bushings can be acquired from Wicks Aircraft supply. WICKS Tubing page

You will of course have to cut it to length.

They also have aircraft grade bolts.

JDDDeere · Post by **JDDDeere** » Thu Jan 31, 2008 10:28 am

JUst to close the book on this...

I installed all the parts (bushings). I think it worked fine. I elected to go with the Nylon flanged bushing on the bottom (these are the ones that come 5 per pack for like $7) where before I had none! They are 1 1/4 inch long but had no problems inserting. As a back up I have a pair of bronze bushings. I used the orig plastic bushing on the top of the spindles as they were still very tight.

As for the ski pivot bushig, agian I used two 1-inch bushings, ground one down a smidge to give exact lengthof old bearing/bushing. Oiled up and inserted. I am intrigued by the Steel tubing offered by WIcks (in Brians post.. that is a very affordable/easy option for steel).

Replaced skis with new bolts.. and wha la... have no more than 1/2 inch of play at the ski tips... can't wait to try but we just lost all our snow!!!!

Also, an aligning tip: I aligned the spindles using a 3/8 in wooden dowel which I inserted thru both pivot bushings when the skis were off.

Thanks for the ideas and help.

(now if anyone has any hood decals or an old speedo cable, that is all I am missing)

Dan

JDT · Post by **JDT** » Thu Jan 31, 2008 12:30 pm

Going back to the idea of using steel tubing around the spindle as a bushing.

This will work but what about the flange?

The entire weight of the front of the sled sits on these two flanges.. As the skis turn from side to side there is friction and wear at this point. If you have an aluminum spindle housing tube (bulkhead) rubbing against a steel spindle base... the alum will loose.

I ran into a sled a year ago that had a similar modification done to it (no flange). The bulkhead tube had worn down so much that the ski saddles were rubbing through the bellypan as they were turned from side to side. The tie-rod position was also raised and they were wearing on the bulkhead also. The machine had to be junked out.

I feel very strongly that the bottom bushing needs to have a flange on it. The bushing fits snugly in the tube so that it will not pivot thus preventing damage to the bulkhead.
And they are very easily replaced.
The top bushing has no weight on it at all but still needs a flange or washer to act as a spacer to maintian the correct length of the spindle to attach the spindle arm.

JDDDeere · Post by **JDDDeere** » Thu Jan 31, 2008 1:28 pm

HI TOdd..

Maybe a mix up?. The nylon bushing I installed on bottom are flanged as are my "back up" set made from bronze.

The steel being proposed/considered would be in place of the two 1-inch bronze "pivot" bushing that holds the ski on.

Thanks again for you help!

Dan

JDT · Post by **JDT** » Thu Jan 31, 2008 1:36 pm

Sure Dan, the steel tube will work fine for a saddle bushing.

What I was talking about was using the steel tube as a spindle bushing.