axle problems

i don’t know if any other teams have had this problem, but our axles seem to have expanded, or else every thing we had on the axle shrank (two bearings and the larger 45 degree gear)

is there any reason why? or any ideas on how to fix it?

my team is planning on just using a dremel to sand them down, but it seems off that they worked one day and stopped the next… (HELP!!! :ahh: )

Ackk don’t dremel it you’ll ruin the whole shaft. Use emery sandpaper because there are burrs on it. The bearings are designed to have a percise fit. These things were hard getting them on with a brand new shaft also.:slight_smile: Any burrs on it will stop them from going on. You also may have mushroomed the ends of the shafts by dropping them or hitting them. Use emery cloth to fix it.:slight_smile: Use the rough cloth to smooth down the ends and the medium and light cloth to smoth down the burs that aren’t at the end.

Absolutely do not bang on the ends of an axle shaft to get things in or out unless you use something “soft”. The 5/8 inch axle is butter-soft and striking the end with anything but a block of wood, plastic hammer or brass rod in between will mushroom the end. If you do mushroom it, not a problem if you’ve left the shaft a hair longer than it needs to be. Just bevel the end slightly on a grinder ( keep the shaft almost parallel to the axis of the grinding wheel shaft). Or you can file the end nearly parallel to the shaft. I’ve had to do this constantly, every time an uninitiated soul bangs on it (or I get frustrated). Tightening down set screws for a shaft collar has the same effect. Use emery paper on a block of wood to reduce the raised metal around the dimple caused by tightening a setscrew. And you can touch the keyway with a bit of sandpaper to get rid of burrs. No biggie. It’s just amazing how a few hammer-taps can mushroom it so much…just look carefully and you can see the bulge at the end. Or lat the shaft down on a flat surface and look for daylight at the bulged end.

You did not specify where you store the parts but since temperatures around the country have been extreme in the last few days, one would have to wonder if the parts have not changed dimension (temporarily) due to the temperature extremes. I wouldn’t modify until I knew what the problem was.

that explains a lot, certain people on my team (cough captains cough) were frustrated because they wanted a working drive system to show our sponsors (who were coming in today)… they’ve been hammering and hitting and dremeling everything so it would work…

the dremel didn’t ruin the shaft when done properly, its the only way i could get all the burrs and snags out, the entire shaft was covered in them!

Mount it up in a drill press, and if you have it, use some emery cloth, if you dont have any, and are strapped for time, use a very very fine toot file and lightly press the file against the turning shaft, and slide the file up and down, as to evenly take off material, and not lose the roundness of the shaft. WARNING: Be very very careful doing this with a file, if you press too hard, or if you dont evenly take off the material, your shaft will no longer be round, and probably useless.

Hope this helps,

Cory

yeah, we’d do that, we did it last year… the school keeps us in a basement room they didn’t use to use, but now its a computer lab, so they moved most of the stuff out of the room, and happened to put OUR drill press in an unused girls bathroom (the one above it flooded or something and it was ruined, so now its storage…)

it seems to be working after i attacked it with a sanding attachment for our dremel… thx a lot

Just remeber that your making the shaft smaller when you sand it. Sand it down too much and it will be too small. Btw emory cloth is much better at getting the job done than a dremel tool.

when the problems happened, we didn’t have time or money to go get an emery cloth, so i did what i could… turns out our school auto-lab had some they could lend us (no one told us that)

it all worked out in the end