Using QCTP holders

[Jim F]

Some people make a clamp type knurler, using the axle bores as pivots.

 

[Grinderman]

I'm actually making a straddle knurling tool similar to Mikey's but will mount on the tool post. The old modified bump tool will hold it to the qctp.

 

[Shotgun]

I think that type of knurler should not even be sold for an AXA set. Because the lathe is likely too small to use it without damaging something

Some say they can damage the spindle bearing with high pressure it needs to be driven into the piece.

Long before the spindle bearing is harmed you are very likely to damage the cross slide lead screw nut with the pressure needed for a good knurl. Be careful putting high pressure on the cross slide lead screw on a small lathe.

Would a 12"x42" Atlas be considered a "small lathe" in this analysis?
It seemed to easily bite into the 3/4" aluminum I had laying around, but it is the big-box hardware store stuff. Probably 3003.

 

[Jim F]

That seems like about the size where the small and large meet.

 

[Illinoyance]

I have good luck with the bump knurl holder. The tricky part is getting both knurls to bear on the work evenly.

 

[Grinderman]

Check the diameter of your wheels. One of the wheels that came on my bump tool was .025 smaller than the other. The Accu Trak wheels I just got for my project we're perfect in all dimensions.

 

[Shotgun]

I have good luck with the bump knurl holder. The tricky part is getting both knurls to bear on the work evenly.

Right. That is the problem I had the first pass. On the second pass, I left the toolholder loose in the post. Just hanging by its adjustment nut on the dovetails. I let the knurler find it's own bearing.

 

[Jim F]

I think that type of knurler should not even be sold for an AXA set. Because the lathe is likely too small to use it without damaging something

Some say they can damage the spindle bearing with high pressure it needs to be driven into the piece.

Long before the spindle bearing is harmed you are very likely to damage the cross slide lead screw nut with the pressure needed for a good knurl. Be careful putting high pressure on the cross slide lead screw on a small lathe.

I have a 1947 SB9C, the spindle is still nice and tight, the cross slide has .010" backlash, the compound has .005" backlash.
I do not want to use anything that will cause any excessive wear.