Bearing extensions

[thebuggyman1]

Aatv's have an inner axle bearing (sometimes a bushing), and an outer bearing at the tub. The outer bearing often acts as the tub seal, but even when it isn't, it protects the seal by holding the axle centered. This design works great for supporting the sprocket tube, but not so great for support of the machines weight. The problem with the design is the cantilever effect. The outer bearing is typically at the mid point on the axle. This makes any force exerted on the wheel doubled at the bearing. Argo uses a cast aluminum bearing extension (optional on most machines) to push the outer bearing closer to the wheel. Recreatives used to sell a cage design, that used additional bearings farther from the tub. Recreatives now sells a different design that I have not seen, but I'm sure it's the same concept. Most often these are used with tracks, but all machines benifit from them.

I made these out of 5" dia. UHMW. They are basically a twist on the older Recreatives cage design, meant for 5" long carriage bolts to hold them to the frame.
I believe these will help to make the bearings last longer, and help protect axles from bending.

[tattooman]

Would you consider selling some of them?

[amphibious drew]

Would you consider selling some of them?

Even better, give us some directions as to how you made them and where you got the material. Also, how hard was it to machine? Did you start with round stock or turn spank square? How much do you have in a piece? I like your idea, and eventually would like a set of tracks on a machine or two, and I like the idea of making some of the components myself. I also think they may be a good keep on my gotcha build. I plan on using some pretty beefy tires any I am sure they would help.

[trevorakm1]

Adair argo sells synthetic bearings of the same idea. They have different lengths. I think they are meant to replace the outer bearing with these synthetic but I 'm thinking you can mill one end to accept the usual outer bearing and acheive the bearing extension concept much cheaper.

[thebuggyman1]

Would you consider selling some of them?

Sorry, but I won't make them for other people. I'm way too slow at machining, and it's on borrowed equipment.

Even better, give us some directions as to how you made them and where you got the material. Also, how hard was it to machine? Did you start with round stock or turn spank square? How much do you have in a piece? I like your idea, and eventually would like a set of tracks on a machine or two, and I like the idea of making some of the components myself. I also think they may be a good keep on my gotcha build. I plan on using some pretty beefy tires any I am sure they would help.

I bought UHMW off Ebay, UHMW White Plastic Rod 5" Dia 045" Oversized x 12" Long Lathe Bar Round Stock | eBay Offered the guy $25 each piece (its approx $30/ft at mcmaster-carr) plus $20 shipping = $120 to make 12 pieces. It's 5" round stock with a rough outer. Because they don't need to be that precise, I didn't clean up the outside dia. The plastic macines very easily, but the tooling needs to be very sharp or you get grooves/ridges, and little hairs left behind.
I can give you a step by step to making them on the lathe and drill press, but I don't want to bore everyone else with that here.

Adair argo sells synthetic bearings of the same idea. They have different lengths. I think they are meant to replace the outer bearing with these synthetic but I 'm thinking you can mill one end to accept the usual outer bearing and acheive the bearing extension concept much cheaper.

I sent Tim an email this morning about providing the service of making them for other members. It took me many hours to make these ones, and I am not finished yet. I'm sure someone experienced could make them FAR faster. I also thought of the synthetic bearing idea, and decided an $8 seal on the outside wasn't much cheaper than a $13 bearing......maybe that's a better idea on the inside too

[trevorakm1]

What I like about yours are they are one peice, from Adair they have to be stacked and more chance of leakage if not paying attention. What I like about the Adair is it allows a guy like me without the facilities to mill to still get the same effect. I was thinking of getting bearing extensions for my bigfoot rear axles due to the stress reasons you mentioned above but that requires alot more modification than I care to tackle. These give the same effect. I can also add these to middle and rear axles cheaper than just one bearing extension. I will probably order them from Tim in April when I order my tracks. I would like to hear some feedback once you get yours installed to see if you notice any difference.

[thebuggyman1]

I bet Tim is making them out of the waste from cutting out track pieces. I really don't see an issue with a 3 piece extension (3X1.5"=4.5"), just use a smear of silicone between them.

As for the feedback, no news will be good news. I'm hoping to NOT have any problems, so NOT notice a difference.

[Obsessed]

I sent Tim an email this morning about providing the service of making them for other members. It took me many hours to make these ones, and I am not finished yet. I'm sure someone experienced could make them FAR faster. I also thought of the synthetic bearing idea, and decided an $8 seal on the outside wasn't much cheaper than a $13 bearing......maybe that's a better idea on the inside too

Hi Jim....got your email this afternoon and found your conversation here.
I like your bearing extension and think its a good concept. I have been working on just about the same thing for the past couple of years.

To give credit where credit is due....Ray Kohls contacted me about 2 years ago with the concept of a plastic replacement bearing and a couple of other unique ideas...he had already successfully built and tested a few and looked like a good replacement for a the common steel type bearing for our application. I had trouble replicating the product with our equipment so the more I thought about it, I also liked the idea of incorporating the plastic bearing with the whole flange as well as an effective bearing extension and axle support...turns out that this was easier for us to build and eliminated the failures that we sometimes see with damaged steel flanges....we have been testing this product for about two years now and so far, so good...you can see pictures of what just a 2" thick bearing along with a factory outer flange looks like when installed on an old 6x6 vanguard if you look on adairargosales.com website under accessories.....we have come to the conclusion that you can either just run the UHMW bearing by its self or if you are rebuilding an old argo you can replace your outer seals in your old outer bearing flanges and use that to cap the outer bearing giving you a grease seal and also an effective device to hold the head of the carriage bolts,....or you can really double up and use the Adair HD Bearing adapter on top of a stack of UHMW bearing to give strength and support to the axle and to take leverage off of the outer HD bearing.

The UHMW bearings we have been machining have been installed on a couple dozen machines now and we are curious to see how they hold up over the next couple of years...eventually, if they continue to test well we will start to recommend they for applications that have trouble with conventional steel bearings...for now we give them to anyone wanting to help with the testing for a cost of about $10 per axle and you can stack them as thick as you have axle length for... To make them universal, we build a lot of them with all three common bolt patterns cut into them...we machine all the bolt patterns about 3/4 the way through the block so that all the user has to do is chose the pattern that matches there machine and then poke the holes the rest of the way through. If you are stacking several blocks together a simple cork gasket is all that is needed to seal up between each layer...so far they have been proving to be very watertight even at minimal thicknesses of just 2"....we now make them in 1" and 1.5" thicknesses to allow for custom applications...

Kghills, and Noel Woods, are just a couple of the guys on here that have been playing with the product...

If anyone want some scraps of this material, we probably throw away about 100 lbs of it on a typical day. We have been experimenting with some other uses for all of the waist but have more than enough to go around.

Let me know if we can be of any help to any of you here...

Tim

[thebuggyman1]

Kudo's to Tim for doing so much to advance our sport.
Sounds like anyone wanting to try these out just needs to stack a few of the Adair design together....even if the bolt holes aren't right, they could just drill the ones they need.
Tim could probably even bore different sized axle holes for older machines like Attex with 1" axles

[thebuggyman1]

I want to link this thread to another relevant thread on the synthetic bearings.

http://www.6x6world.com/forums/max-atvs/25546-older-max-iv-adair-synthetic-bearings.html#post138124

[thebuggyman1]

It's been a real long winter, and I lost all motivation in the cold weather, but I'm finally back on my project.
They all went together well, and I'm looking forward to the first test drive.

[PlumCrazy]

They look good Jim.
Let me know how they hold up.
What engine do you have in that Max, do you expect to loose some performance due to the additional resistance of the extensions?
ed

[thebuggyman1]

All I had laying around was a briggs opposed twin 16hp, so it is going to be a bit under powered. I don't see how the extensions will eat up any additional hp though.

[Czechsix]

Subbed to this thread. I'm kinda curious to see how durable they are too. Good thing is they're easy to make...at least easier than casting some aluminum, which is what I was thinking.

[phabib]

I got the plastic in the mail a couple of days ago and I'm going to make some as well. I notice that you've got a seal in your design. It looks like it is on the inboard end, and positioned so that it would stop stuff from going from the inside of the tub out. Do I have that right? Can you talk about why you added the seal, where and which direction you placed it, and why you decided to add it?

Thanks for the photos and good idea.