dealing with crimp marks in stock axles?

[Cooper]

Our district rules say we must use stock axles (Revell is not an option). What would be the best way to deal with the crimp marks? The burrs at the top are easy enough to file away, but the 3 crimp marks a little further down the shaft are another story.

Removing them completely significantly reduces the shaft diameter. Would it be better to just leave them and polish as best as possible with them there? I can always position the axles so the crimp marks face the top of the wheel, so in theory, they'd never touch the wheel bore. What would you do if you had no choice but to use stock axles?

We're graphite only (no oil allowed) if that matters.

 

[HurriCrane Racing]

If you must use the axels in the box, I would mark the head in correlation to the crimp marks. Carefully file the three crimp marks off with a file. I would not do this with the axel spinning. Once the crimp marks are removed, you can chuck it in a drill and polish the axel.

When you install the axel, orientate the mark indicating where the crimp marks were pointing straight up. This will ensure that the wheels are riding on what I would believe is the roundest part of the axel. Hopefully this will minimize the amount you have to reduce the diameter of the axel

 

[ngyoung]

Can you groove the axles? If so the crimp marks are pretty much in the spot where you would want to file a groove. If not do what Hurricrane said and file them off before putting in a drill.

 

[Crash Enburn]

+1 That's what we did. (Grooved the axles right there)

 

[Cooper]

Hmm.. Rules say "must use axles from the box" and "they may be modified by polishing". It doesn't say they can't be grooved.

Maybe we'll try grooving a set & see how it does on the test track. I almost want to stop now though.. It's already the fastest car we've built by almost .01 (based on our homemade track times). I'm afraid to mess with it anymore.

 

[ngyoung]

Then do it on a new set of axles. You should be able to get more official BSA axles from your local scout shop. Since you have a test track at least you can check if you're gaining speed or not if you do a few different sets to experiment. Testing different stuff out with your scout is half the fun sometimes.

 

[davet]

We mark the heads in line with the 2 burrs under the head. We then K-Groove on the mark. We install our axles with the K-Groove laying on the side (front to back) so we can have a smooth half on top to mark our 12:00 position which after getting aligned will then be wiped off and a new mark engraved in at the new 12:00. This helps when reprepping and the alcohol wipes off the marker. Sometimes the axles needs a little twisting and can make marking a new 12:00 difficult if the K-Groove is say, at 11:00 or 1:00. This is why we don't use the K-Groove as the 12:00 mark.

The stock axles are oblong (egg shaped). We install our axles with the wide part fore-aft (K-Groove running front to back) as if the egg were laying on it's side. This gives you the full .091" diameter fore-aft so you get less toe change.

We put our axle in the jig to cut the K-Groove first. Then we chuck it up in drill press and lay an 1/8" wide file on the drill press table. Raise the table so that the file covers all three crimp marks at the same time. Turn on drill press and lightly pull the file into crimp marks until they're gone. Like has been said, this is the perfect place for the groove. The drill press table must be absolutely perfectly square to the axle when grooving. When pulling the file into the axle go lightly. We've bent a few axles this way trying go faster. Also, pull the file into axle from the sides and from the front and back. This will help minimize any very minor table alignment issue. Our experience has been that if the table is even a few thousandths off, the groove will cause a wheel vibration.

Also, John sells stock axles in bulk much cheaper than buying the wheels/axles together at the Scout Shop.

 

[Guest]

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[HurriCrane Racing]

The new Revel axels have a machined point.

 

[BulldogRacing]

belt sand the flat spots. LOL