uggg.
We should also consider whacking off the butt of each of those tools.
Ooh, those look sexy. Thanks @hon1nbo for this lathe. I expect it will see a lot of use from people would would have never ventured into CNC on the Haus. You migth even change someone life with this act of selflessness.
Oh it gets better. Iâll write it up later when I get home. Short of it- donât try drilling yet
Started the morning setting up some tools and getting the correct height locked down. Here it is old school - using a brad point drill bit in the 3 jaw chuck (didnât have a 5C collet that fit). BTW @TBJK I didnât find a chuck key for the 5C collet chuck. The ones from the other lathes didnât fit. Probably some metric POS.
Here are 4 of the tools set up and ready to go. Canât say many good things about the drill chuck but more on that shortly. Broke in the other ones:
Here are the first two operations from Maxâs pawn project for the Sherline CNC. Very little tweeking was necessary to load it into the PathPilot. However - some spacial distortion does seem to occur. Even though I had a 3" bar loaded, and the pawn is 2" long, PP decided to put them 1.5" over the physical limit of the lathe and no amount of touch off fixed it. I ended up just using a longer bar and telling PP it is further down the bed. Either way it worked out but it may lead to other problems for gcode generated outside of PP. I didnât find a finishing file on the committee drive so only broke it in to the 3rd op.
Ok, last but not least - Drilling. It is logical to assume you want the drill bit in the center of rotation of the lathe. Anyone know what that magic offset is? Path Pilot sure doesnât. so if youâre off center your drill hole isnât going to come out. A good amount of time was spent trying to find that number. Thanks to @procterc and @BobKarnaugh for brainstorming some ideas on how to find it. Charles and I found a good way to find that number (or so we thought). Later when actually trying to run the drill things werenât working out as we expected. What we eventually discovered was that the tool holder block had rotated away from center by quite a bit (>40 thousandths) from center. I discovered it when I noticed an air gap between the block and adjustment screws. SO why were things working? Well a regular tool doesnât care if it is cocked or not. It runs parallel to the bed so any cutter also running parallel cuts an equal amount so long as the cutter is in contact.
A drill on the other hand - it matters a lot if youâre off center. So when we ran it we were getting an oblong hole. Because the drill is off center the magic number we found is worthless (sorry Charles) so weâll have to set it up again to find it. Bob and I adjusted it back into center but canât test it until I find the magic number. Setting drill operations will be a pain in the azz for everyone. BTW, the root cause is the lightweight bolt used to secure the tool block. So because we donât know the magic number yet, DONâT RUN DRILL OPERATIONS @Paul_Morley. it will bend and break! We saw other problems such as the 5C collet slipping.
It was a long day, and in the end generated more work to be done. But it was progress none the less. Hoping to have class slides done next week. CHEERS!
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BTW, that tool on the right is mostly a groover and not a parting tool. It only has about 1" of depth clearance. The parting blades from the Sherline wonât work. They are too thin to be held in our current 0AX25 holders. Weâll need to locate another type of cutoff blades. cheers!
The key for the 3 jaw is in the teachers cabinet since it doesnât have a spring.
Didnât we try the peck drilling before?
Iâm hoping I might be up there early next week to look.(stupid on call)
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yes but it was just drilling air.
Not even using a lathe myself yet, being able to come up with a multi-operation program in a few minutes like that is a game changer. Thatâs really impressive.
If the tool holder is that difficult to align for drilling, and since we have reference posts and all drilling should be completely coaxial, does it make sense to create a custom tool holder that has a positive alignment? Like some perpendicular grooves in the bottom to square it with the saddle bars?
FWIW, there are some oddball cutoff blades either in the end mill / drill cabinet or the teacherâs cabinet. I think they were in a small wooden box.
they need to be 1/2 tall to fit our tool holders. if they donât fit the sherline they wonât fit the tormach. Thank you for letting me know. Iâll take a look sometime next week. cheers!
I think something different would be better if it is one solid body. The jacobs chuck in a separate morse taper in a tool block that can move is going to go out of whack more than once. More on that later.
The ones I recall are not half-inch cutoff tools.
However, we have two different so-called half-inch cutoff tools for the Sherline.
The cutoff tool holder for the quick change tool post will actually take a half-inch cutoff tool. We are using a $7 cutter from Little Machine Shop in that holder. I believe there might have been one spare one in a plastic sleeve in the Sherline cabinet.
However, the cutoff tool rear toolpost doesnât hold a true 1/2" tool. Sherline custom grinds their parting tools to fit that holder. We currently have a $20 Sherline-brand cutoff tool in that holder because the off-brand ones donât fit. If you have to appropriate a blade from the Sherline, please donât take it from the rear holder because nothing else fits in that slot.
One solid body was my thought; I can take some measurements and draft something up in CAD. We do have all those Jacobs chucks we took off the turret drill press.
We can make a prototype without too much work