Hello there,
small but important update,
Knurling.
bane of my existence!
Knurling is hard to make on a relatively small lathe. There are also different type of knurling and knurling tools. Diamond knurling is actually simpler to make because it is made with a double wheel that each does one diagonal. You tighten the tool itself, don't really push with the lathe chariot.
Straight knurling is hell.
you have to push the tool into the material really hard to make the knurl appear little by little. The thing is, with my lathe, the material was usually stronger than the tightening of the lathe chariot and tool holder, so they started to turn more and more as i pushed on the material, never really managing to get into the material.
So, I added a first strong screw to hold the tool holder better and prevent him for rotating when pushing into the material, but then the perpendicular charriot started to turn on its axis as well and this one is harder to prevent.
I disassembled the whole system today to drill into it and add another screw that will only be there when doing knurling.
here is the lathe without any tool support anymore, good opportunity to cleanup everything as I never removed the big charriot before.
all the parts...
and now we want to drill a 6mm hole into 5cm deep of tool steel! yay!
luckily I have great drill bits now that will drill into really anything, so it's not that hard anymore. It was a lot harder the first time I had to adapt that tool holder to the lathe!
anyways, didn't take other photos of the process, but here is the lathe reassembled with the two additional 12.8 quality steel screws:
Screw #2 can obviously only be there when I do knurling and needs to be removed when using the chariot. screw #1 can be there most of the time and rigidifies the whole tool holder nicelly
#2 is doing a great job at keeping the charriot perpendicular now. However, with my last test, it seems the tool holder is still rotating a bit now even with screw #1! I have tightened everything a bit more tonight, i'll see if it works or if needs a 3rd screw!
in any case, mostly successful, this is the best straight knurling that came out of that lathe so far! knurls are well formed. I have still a bit that I would like to improve, but it has mostly to do with how to hold the part. But it looks like we will get nice knurled end caps for this run
cheers all!