Author Topic: De-Burring Gear Teeth  (Read 113 times)

0 Members and 1 Guest are viewing this topic.

Offline Peaky 556

De-Burring Gear Teeth
« on: Jan 04 2019 21:52 »
Does anyone have a cracking way of cleaning off the burrs left on aluminium or steel gear teeth after facing the sides of gearwheels?
I’ve been cleaning up the gap between every pair of teeth using a small, suitably shaped, diamond file.  It does get rather tedious though on 60-tooth gears!
Thanks, Tim

Offline Doddy

Re: De-Burring Gear Teeth
« Reply #1 on: Jan 05 2019 10:20 »
spinning soft wire brushes?
"You don't know what you don't know"

Offline IanT

Re: De-Burring Gear Teeth
« Reply #2 on: Jan 05 2019 14:12 »
"after facing the sides of gearwheels?"

Are you modifying an existing (commercial) gear Tim - or are you doing this after cutting them?

I've cut (larger DP) gears in cast iron some years ago and there were no issues with clean-up afterwards but other materials may well have problems. I hope to cut some 0.75MOD brass gears later this year (when it's warmer). My current thinking is to cut N+1 'finished' blanks for each size required and then pin them together and cut them in one (full rotary) pass for each size. The +1 will be at the end of cut and should be the only one with exit burrs (but hopefully still potentially useful as a spare). If I was cutting just a single gear - I'd probably use a backing plate of some sort - hardwood might be quite good enough. These might need a little polish on emery paper (held flat on plate glass) but I would hope not to have to clean up the actual teeth.

If the burrs are the result of secondary machining after tooth cutting - then I think a nylon brush might help - especially with aluminium gears. I have various wire and nylon 'brush' fittings for my Dremel - and prefer the nylon (plastic?) ones but they don't last very long. The wire ones tend to fling more sharp bits about that end up everywhere. Often an old toothbrush can also be handy to clean work up - small burrs sometimes don't need much assistance to peel off. If the burrs are thicker/larger - then maybe the cut could be improved (sharper cutter or faster/slower speed?).

That's my 2p - Good Luck!   :-)

IanT
Nothing's ever Easy - At least the first time around.

Offline Peaky 556

Re: De-Burring Gear Teeth
« Reply #3 on: Jan 05 2019 20:52 »
Ian, I’m facing the sides of commercial gears in three materials; aluminium, brass and steel.  I don’t have the experience or equipment to cut my own gears but I have found a source of good quality and good value ones to modify.  After turning I might have inadvertently made things worse by trying to chamfer the edges with a file whilst spinning.  Yes I know it’s a crude cheat but often gives a quicker result for non critical chamfers!  Yes it’s possible that the burrs may have been very soft and thin following facing with a TCT tool, and were just exacerbated by the file.  On the next batch I shall proceed more cautiously!
Doddy’s idea of a soft wire brush may have worked, particularly for the ally gear, perhaps whilst turning in the lathe.  Again, I’ll think more next time!
Incidentally, the steel was by far the worst, followed by the aluminium, whilst the brass doesn’t really display burrs.  I can believe that your cast iron was pretty burr-free too.  Must be something to do with ductility...
Regards,
Tim