Axle and bearing question

[lioni05]

Hello all,
I have been quietly and slowly building a LodeRunner type vehicle using Brads plans. I have finally got to the part where i begun to have assemble the drive train and rear axle. I have spent a fair amount of time trying to make sure that the rear axle and wheels are properly aligned, and am almost ready to cut the axle. However, before i do this i wanted to ask a couple questions. While the axle fits through all four bearings, it does require a fair bit of tapping with a mallet to get it to slide through. Is this fairly normal, or does it mean that the bearing are misaligned. There also seems to be some resistance when rotating the axle shaft in the bearings. Is this also normal, or again is this the sign of some type of bearing misalignment? Thanks in advance. You all are a storehouse of knowledge.

[JayRay]

Hi Lioni05,
First I must say this, pictures please!
I would love to see another
LodeRunner being built.

OK, I feel better now... :cheesy:

I had the same experience with my rear axle that you are having.
What type of bearings are you using? Are they "fixed" or do the
centers "self adjust" like the ones I used? The bearings are very
tight in the housings but they will rotate with the right amount
of "influence". See photo below.

http://i459.photobucket.com/albums/qq317/JustJay2009/Parts/th_Bearing.jpg (http://s459.photobucket.com/albums/qq317/JustJay2009/Parts/?action=view&current=Bearing.jpg)
(click above image to see full size)

First thing I would do would be to make sure the axle is clean and
rust free. I rubbed it down with fine emery cloth and also oiled it up.

I used a modified center bearing support but I do not think that is
what caused the tightness. It probably had more to do with heat
deformation from welding. I mounted my axle to my side supports
first, aligned it and bolted it in place and then attached my center
support. See photos below.

Please note: Distortion in photos is due to fish eye effect of camera lens
(Click any photo below to see full size)

http://i459.photobucket.com/albums/qq317/JustJay2009/Back%20End/th_BackEnd-6.jpg (http://s459.photobucket.com/albums/qq317/JustJay2009/Back%20End/?action=view&current=BackEnd-6.jpg)

http://i459.photobucket.com/albums/qq317/JustJay2009/Assembly/th_Assembly-13.jpg (http://s459.photobucket.com/albums/qq317/JustJay2009/Assembly/?action=view&current=Assembly-13.jpg)

http://i459.photobucket.com/albums/qq317/JustJay2009/Assembly/th_Assembly-14.jpg (http://s459.photobucket.com/albums/qq317/JustJay2009/Assembly/?action=view&current=Assembly-14.jpg)

http://i459.photobucket.com/albums/qq317/JustJay2009/Assembly/th_Assembly-16.jpg (http://s459.photobucket.com/albums/qq317/JustJay2009/Assembly/?action=view&current=Assembly-16.jpg)

Once I was done I found it near impossible to remove the axle. I had to beat
it out with a mallet. In order to slide it back through all four bearings I had
to start on one side, slide the axle in the bearing up to the center one then
"twist" the self adjusting bearings to line them up. Then using a cut off piece
of axle I adjusted the center bearing and was able to get the axle into both
bearings. I did the same from the other side and was able to slide the axle
in from both sides to the first middle bearing easily but not into the second.

The only way I was able to get it all the way through all four was to use
the cut off piece to "adjust" the two center bearings first so the axle
slid through and then redo the sides so they aligned with the middle ones.

The axle alone always felt like it had some resistance while turning it.
Once I had the wheels on it spun like a dream.
I hope my ramblings are helpful.
Jay

[lioni05]

Thanks for the reply. That is absolutely helpful. I have cleaned and lightly sanded the axle with metal grade paper. It sounds as though I followed the same procedure for mounting the axle. In fact, I have to admit, that I used your modified bearing supports, including the center mount support idea. It sounds as though your axle was a little more difficult to to remove/move than mine. I think this means that I'm not that far off track? I haven't yet removed the axle completely and tried to reinstall it since intalling the center support bearings - so i guess we'll see. I will try that tonight and cross my fingers.

I will definitely post pictures soon. I am a little embarrased to admit that, as this is my first build and i am a novice welder, I took a little easier route and decided to hack an old Rhoades Car that I found. So essentially what have done is chopped the rear and added the rear box from the LodeRunner to the RC. I have an ETEK motor and Kelly controller combo that I plan on adding as well. The ETEK, attached to a freewheeling sprocket, will drive one side of the axle, pedals the other. Eventually I plan on adding a trailer via hitch that will pull a small bench seat so friends can enjoy the ride. Needless to say I have alot of work ahead.