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Logan gear fix - Printable Version

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Logan gear fix - Vinny - 07-30-2015

I picked up a quick change gearbox for my Logan 200 for about $100 a while back.  I knew in advance that there were some bad gears in it.  The guy I got it from posted lots of pics.  Complete ones were going for between $350 and $500 but the serial number they came from was unknown and after a certain serial number you had to use a different gearbox.

First thing I thought was to make plastic gears to replace them (since Logan wants $200 ea and I needed two) and they worked for a while but didn't last.  Tried different resin, those lasted longer but still didn't last.  

Note: these gears are a cluster of a 16 tooth and a 32 tooth.

Ok, time to go back to steel gears.  I saw a tubalcain video (mr pete) on how he fixed the same gear.  He found a 16 tooth gear with a hub on ebay.  I must have found the same gears 'cuze we both had the same problem.  When the old one was split and the bad gear removed, the hub was smaller than the hole in the 32T gear.  

Sorry for the blurry pics, I'll retake what I can and post later.  This is after the split, you can see how the smaller one is almost completely toothless.
[Image: gears3.jpg]

Here's one of the new gears
[Image: gears2.jpg]

So I need to make a couple of bushings which I forgot to take pics of.  Anyway, I made the bushings out of some DOM steel tubing I have that I'm making a drawbar out of.  

Next step was to bore out the 16T gear to 0.500".  For that I just held the hub in a collet.  No pics of this either but the end result can be seen here.  At this point they're pressed together and ready for the oillite bushings to be pressed in.
[Image: gears1.jpg]

With the oillite bushings pressed in it was time to drill the holes for the pins.  Following mr pete's advise, I didn't use the old holes, rather drill new ones.  How to hold the gear in a vise to drill?  I didn't want to chance screwing up the new gears so I made a quick pot chuck out of plastic (yeah, I use a lot of plastic) and put the gear in that then squeezed it in the vise.  

Here's the end result, pins installed and the blurry whitish thing next to the gears is the pot chuck (something else to take a better pic of).
[Image: gears4.jpg]

I still have two more to do, they're the ones in one of the selector handles.  For now those are plastic but I now have a gear hob that I'll use to clean the old ones up.  

About the blurry pics, I used my new tablet for it and it just doesn't compare to my fone, so that's what I'll use to retake some.

That's all folks!


RE: Logan gear fix - krv3000 - 07-30-2015

you will get their in the end