POTD was wiring in a Millfast Products remote control panel to my Tormach. The previous owner of the mill had a full enclosure and used the ESC key on the keyboard for an E-stop switch. It works, but I prefer a big red switch to hit. I decided to mount the control box to the lower RH side of the front door. The doors can swing open, so plan was to route the wiring up to the hinge of the door, then around to the back of the mill and into the enclosure/controller.
The doors on the enclosure can be removed, so needed a way to remove the Millfast box from the swing door as it's hard-wired to the controller. Ended up screwing an aluminum plate to the door frame using a couple of Creform brackets. The plate has a couple of 1/4"-20 tapped holes for mounting a second aluminum plate screwed to the bottom of the Millfast control box. I could have mounted the adapter plate on the control box to the base with a couple of 1/4"-20 cap screws, but figured I might as well make some thumbscrews and single-point thread them with a new Aloris No. 8 threading tool holder.
Chucked up some 1/2" brass and turned a shoulder to 0.249"
Used a parting tool to relieve the thread at the base
First scratch pass and verification it's at 20 tpi
Last pass
Verified the thread was at the target 0.2175" pitch diameter
Knurled
Parted
Made a second thumbscrew using a carbide insert
Made one screw with a brand new Aloris threading tool and a second with a carbide insert. So which do I prefer? Pluses and minuses for each. The Aloris tool is wider, so I was just about hitting the base of the screw at the end of the cut. The thread quality with the Aloris tool was better than the insert. However, the Aloris is brand new and sharp, the insert in my threading tool has probably cut 50 threads. The jury is still out, need to pop on a new carbide insert and do some better apples to apples comparisons.
The Millfast control box E-stop switch has to be wired in series with the Tormach controller E-stop switch. Not a big deal; route the cable from the control box to the side of the Tormach controller, remove an access plate and replace the plate with one provided by Millfast. I was starting to doubt my dexterity as I got one screw in the new plate, but couldn't get a second one in. "Oh, can't be old me and my hands full of thumbs?!?". Well, it WASN'T me for once. Maybe Tormach has different hole patterns on the controller access panels, but the Millfast one wasn't even close. I made a new plate from 0.050" stainless.
Millfast plate on the left (control box wire routes through the center hole) and the stock Tormach one on the right. Millfast holes were off by about 1/4", though maybe Tormach has variations on their hole pattern. My original plan was to punch a hole through the center of the Tormach plate (hence, the center punched hole), but went with a new part instead.
Punched a 5/8" hole in some 0.050" stainless
Punched the 4 screw holes with a Roper Whitney No. 5 punch. Trimmed to size with a bench shear.
Fool me twice. . . checking alignment of my plate on top of Tormach's plate
Millfast control box mounted to the RH door. I routed the wire to the hinge of the door, so can still swing the door open without tugging on the wiring.
Aluminum plate fastened to the door. If the door needs to be removed, back off the two brass thumbscrews and set the control box on the keyboard table.
Thanks for looking,
Bruce
