POTD was more progress on the enclosure for my Tormach mill. The enclosure will have a 6" table that overhangs the front of the mill. I have stainless steel tubing that runs along the front edge which needed to be braced back to the chip pan for stiffness.
There are 4 brass plugs in the front of the chip pan that can be removed for anchor points for a lower support bracket. I started by making new ones out of brass. Plan was to make bushings with a threaded inside hole for screwing brackets to. They mic'd at around 0.629" or very close to 16 mm or a touch over 5/8". The thread pitch was spot on to both 1.4 mm or 18 threads/inch. I had some 5/8" brass so went with English plugs: 5/8" OD threaded at 18 threads/inch though they very well could be M16 x 1.4. They mic'd at the same diameter at both ends, so not a pipe thread. Too bad, would have liked to try threading on my Grizzly G0709 lathe with a taper attachment.
Plugged holes in the base of the chip pan
Chucked up some 5/8" brass and faced.
center drilled
tap drilled for 5/16"-18
power tapped with a spiral flute tap
scratch pass on the OD for the 18 tpi. "Close enough" as I'm guessing it was probably a metric 1.4 mm pitch thread which works out to 18.14 tpi.
Used a screw pitch micrometer to measure one of the plugs with a 0.600" pitch diameter.
Last pass
Low and behold, hit 0.600"!
parting off the bushings
used a thread repair file at the chucked end that had just been parted. Ran the lathe in reverse and held the file on the back side of the work. That way the file worked itself off the thread.
Original plugs to the left, new bushings in the middle. Some 5/16" cap screws for threading in the bushings.
New bushings in place. Put a drop of red Loctite on the bushings and ran the cap screws down. I put a piece of masking tape between the washer and the bushing which made removing the cap screws easier; didn't unscrew the bushings.
Next step was making some brackets for the bottom support. I used 1 1/2" angle iron for these. Rough cut the length on my band saw, then cleaned up one end on the Bridgeport. Flipped the pieces and cleaned up the opposite side so they were all the same width. Ran a quick CNC routine to cut a radius on the end. Then spot drilled and drilled a through hole for screwing a Creform tube bracket to.
Set the rough cut angle pieces vertically and cleaned up the ends.
Ran a CNC routine to cut a radius on the end, then spot drilled holes which were completed on the drill press.
Assembled two brackets together and drilled the attaching holes to the chip pan on the BP. Spacing is 1.60" on the Tormach chip pan, so matched that on the BP.
Screwed the brackets to the Tormach chip pan and attached some braces from the tubing that runs along the front of the mill. Really stiffens things up.
Thanks for looking,
Bruce
