Bridgeport Interact 4 Series 2 to Acorn6 build

[richardb15]

As a reason to get to grips with using the machine/CNC12 it seems a good thing to be making these plates and bits for the rotary axes setup. I've been on machining the adaptor plates, so holes, chamfers, pockets and DXF profiles. Also I didn't have any 8mm plate so was face milling 10mm plate down to 8mm, all good swarfy fun:



The various parts now machined up that adapt the NEMA34 motort/encoder to the old ABB motor, location bearing and gear:


The whole lot is assembled up then I can tighten those two clamp bolts in the shaft, everything should self align by doing that:


Ready to go together:


This is the motor and gear shaft assembly all done, feels nice turning it over by hand so high hopes!


There is one mounted on the robot wrist thing:


I'll assemble up the other motor tomorrow then start machining the various plates to mount the wrist on the machine, and maybe start extending the wiring and fitting plugs to the machine so I can remove the rotary setup when not in use.

My coolant pump stopped working today while doing those plates, no voltage to it, so need to investigate that too. Two forward, one back!

[richardb15]

With the second motor mounted up onto the wrist gearbox I could connect one of the motors up to the drive directly just to test it. I need to go and buy more screened cable hence not wired up properly, and I'm waiting on the 6th axis drive to turn up from China. Still, at least it gave me some practice configuring a rotary axis and just seeing if this setup will even work:



So the good news is it works! Pretty happy with that, super smooth and quiet The maybe not so good news is I didn't realise as the wrist moves up/down in the video you can probably see that is turns the other axis slightly. It means for dual axis moves I'm going to have to compensate for that somehow, its a simple maths relationship but how I get a command to the A axis to part move the B, I'm not sure, more reading to do!

I fixed the coolant pump, it is 110v and wired into the Acorn external relay board OUT2, but it seems that relay has died. It may well be that I forgot to wire in the snubber so I now have a 15 output system, good job I don't need that many. I've just wired a 24v relay into a different output then use that relay to drive the coolant pump with a snubber, so at least if it fries again it won't be the Acorn bits.

[richardb15]

As an excuse for learning CNC12 I set about doing all the holes, counterbores and just for fun some pockets and chamfers practice too on the base plate for the A-B axis setup. Base plate below, I also did the side and main upright plate, lots of holes and edge squaring up but all good



I can then assemble it up ready for mounting the wrist assembly





Next job is to extend the wiring from the drives, make a chuck mounting plate then get the C axis drive wired up.

[richardb15]

Rotary axis chuck/face adapter plate done, I even got brave and thread milled the mount holes. For some unknown reason I dug through my bolt box and the only cap heads in stock to fit the 3 jaw chuck were M10 x 1.25, and I don't have a tap that size, so Intercon/CNC12 to the rescue!



With that I could losely assemble up the mounts, plates and chuck. I need to reverse the mount as the main plate should be under the orange gearbox, not the motors, but it turns out on trial assembly someone..... used the wrong side of the plate in the DXF file and the dowel holes are a mirror of where they should be. I'll fix those tomorrow and assemble it up with the proper bolts in everything.



I also wired up the B axis drive and tested it, then configured CNC12 so that is ready to go. So two dowel holes, a bit of assembly and some wiring extension work this bit of the project will be done

[suntravel]

Why do you want to mount it along Y as a B axis?

Uwe

[richardb15]

Why do you want to mount it along Y as a B axis?

Uwe

I thought normal naming was A rotates around X, B rotates around Y and C rotates around Z. But... of course with such a device like my setup I have around +100 / -20 deg movement on one axis and full 360 on the other. My plan was to mount the unit at one end of the machine bed so the 360deg rotation axis lays along the X axis usually, this gives the most table movement available for 4th axis work which would be the most common. The B axis would therefore be along the Y axis when the chuck axis is horizontal, but of course when the B rotates to 90deg it would place the chuck axis vertical, so in line with the Z. In the end its all nomenclature but the setup I've got fits on the machine best with the full 360deg axis along the X. I hope that makes sense! Would you recommend a different layout?

[richardb15]

Finally I got round to wiring up the last DB15 connector, my sausage fingers and eyesight are not compatible with soldering tiny signal wires to the back of DB15 and DB44 plugs, so I use these breakout plugs, so much easier and reusable too:



There is the completed rotary axes setup ready to plug in and test on the machine. You can just about see that I had removed the head rotation axis plugs and threaded them so I could bolt through the frame side plates directly to the wrist assembly, making it super rigid. I will make a swarf/splash guard for over the motors next time I'm doing sheetmetal stuff. I must also clean out the remains of the wasp nest that is still there



So after a bit of calibration work with my big engine timing disc and running it round 10 turns for accuracy, I think we are ready to go!

[richardb15]

I've been too busy machining jigs for jobs so not had much time on this, but did get half an hour today to mess about with sorting a degree engraving file so i can do my A axis ring. Uwe very kindly set me his NC file so after some manual editing and find/replace work in notepad++ I got it running on my machine and it seems to be doing the right stuff. Next step is to get brave, mount the rotary setup onto the machine bed, then stick an engraving tool in the spindle and see if I can do the degree marks and numbers on the A axis ring. My grateful thanks to Uwe for the advice and NC file!

[richardb15]

After what seemed like days of machining jig/fixture plates it was finally time to do a cylinder boring test. One of the main reasons for doing this project was to have the capability to bore blind cylinders for veteran engines, as no-one can or wants to do that kind of work any more it seems. This is a cylinder off a 1912 Triumph 500cc, 85mm bore and 190mm deep. The issue with the Bridgeport, and any quill type mill, is they usually only have about 6" of travel, not enough to bore those cylinders. That is why I have motorised the knee (my W axis) as that has over 300mm travel. I can then use the Z and W axes in conjunction for boring ops. This was an old scrap cylinder as a first trial, all went well! You can see the Z going down and the W going up, then reversing at the end of the bore as it backs out.

[suntravel]

The boring is looking very good.

Why not only with the W axis?

Uwe