Gear repair

[f350ca]

I need to repair the tips of the teeth on this gear. Its the pinion that mates to the rack on a Hardinge HLV lathe. I plan to build up the damaged teeth with bronze brazing rod, then machine them with a single point cutter.
There is a bearing surface just below the gear that a needle bearing runs on, I assume its hardened but the gear isn't very hard, it can be filed. If I let the shaft air cool I'm guessing I'd soften the shaft. Should I quench it in oil them temper it?

[Sunset Machine]

I'd not worry about it. If the two gears are soft like you indicate, it would have been unlikely they hardened just the bearing race. Also check the rack - it was probably damaged too. Looks like a full engagement wasn't present, just the tips.

[dallen]

brazing rod isn't very hard nor will it take a lot of wear, wouldn't it be better to seeing as how your going to have to make a cutter, to just make a new gear then turn off the damaged one and press on a replacement.

[f350ca]

The rack looks fine ? so don't know how the damage was done. Seams like your right on the full engagement but it still traveled fine, only felt rough intermittently. (didn't line up to one turn of the pinion)
Dallen, if the whole tooth was missing I wouldn't rely on the bronze but just to rebuild the tips it might be worth a shot. Will consider the new gear though, its not a bad idea.

I don't do a lot of brazing as of late. The rod I have got damp in the last move and storage so the flux is flacking off, will the brush on flux for silver solder work.

Thanks for the thoughts guys.

[dallen]

should but try it on something else first

[Mayhem]

Hi Greg - I have fixed some broken teeth on gears using a couple of different methods, which I have outlined HERE.

So far, I have not seen any wear issues but they are only on the back gears/bull gear.