Turned down two 12.9 bolts, and some other bits. Snapped both of my ph horn mini boring bars No idea why /how either.
Normally not enough rpm coupled with too bigger cut/ too aggressive feed...Unfortunately Carbide has very little flex in it. Can also be tool height above center with play in the cross slide and it pulls the bar down,snapping it off....
M13x1.0 screw in en16t for my cam chain tensioner. I wanted fine for easier adjustment and limited by tools as I dont have an m12 fine tap, Ive got to screw cut the nut. I'll use an 11NL tool and the smallest bore it will fit is 12mm after quite a lot of grinding, so M13. I could have used m10x1 tap/die and saved a lot of time.
I do much of my work in the evening, often up to 10pm-midnight, have my diner after or I dont get much done. Problem it stops me doing noisey work like grinding, tho doesnt stop me swearing, when I found I had more to grind off. I use marker to check rubbing and there is none, and Ive got 2mm clearance to allow backing out Anyway I now have it all set up for the M13x1.0 nut. I couldnt find a drill size but it seems 1mm pitch bores are 0.9mm less than the size, so Ive bored to 12.1mm.
For metric it is simple, just deduct the pitch from the diameter and it will be close enough for most threads.
Not quite right. The nut length is a bit excessive 37mm long, screw thread is about 80mm, and it is binding about 33mm in. Straight infeed distance should be 0.54mm (1.08mm). I am upto 0.62mm, (1.24mm) and dont want to make it tooo loose. That took ages. I think the screw had a burr gave it a quick sand and now it is fine
What he said. If you want to play around with different thread engagements (as opposed to the circa 75% that the diameter – pitch thing assumes) I made a calculator: https://www.cgtk.co.uk/metalwork/calculators/tapdrill - it's completely unnecessary for most purposes, but can be handy for thin or hard materials.
Locking nut. This was much quicker, tho was not a through bore like the last. I cut a 2mm wide relief at full depth to start, 1mm away from shoulder. I do like threading away from chuck!
I've never tried that, given that the insert is on top I assume you are running the spindle backwards, which theoretically I can't do but would probably be ok with for light passes.
I don't get much chance to do any machining right now so a rare treat today. Turned up a housing to hold a small toroidal transformer. The power feed on my HLV needs 110V but I only have 230v in there which was driving the 1750rpm motor at over 4000rpm so I wired this unit as an autotransformer to halve the voltage (It has a split primary winding). It was too big to fit in the control box and I didn't want to run wires up and down the length of the machine to put it in the cabinet. So I bored out a chunk of the ally I got from Pressbrake1 and turned the OD and a step in the end. The control box has a handy round cover just right for converting into a mount. I left the ring 10 thou tight and heated it up with a torch then shrunk it in place and glued an insulator in the bottom of the well. Transformer fits nice and snug. All fits like a glove in the back of the control box.
Land rover TD5 manifold for a friend, about 1.5mm of warp over its length. Had to get a bit creative with the setup being careful not to flex it...looks jenky but it worked! It's now flat enough that no light could be seen through it when placed on the table.
Glued some teeth on a cast iron gear tonight. Came out nice. It did ring a bit as it's a hard SG iron but at least the teeth will stay on.
Helping out a neighbour removing a concreted fence post yesterday. We were not getting very far, I made up an sds core drill adaptor (to be used without hammer). But by the he had it done...