New to me 1929 wide (heavy?) 9" long bed and overhead silent drive casting trade

[mattthemuppet2]

a very VERY big thanks to George Bulliss for his help with this - it would have been considerably harder without the help file and sketch.

Got the treadmill motor running with an MC2100 drive and Arduino a few moments ago, super pumped about that. This is the motor that was on my Atlas 618 and it will be going on my new to me South Bend wide 9. I know that the MC60 drive that's on my lathe and mill can't give this motor the beans it needs, which isn't a big deal on the Atlas (can't use those beans) but probably will be on the SB. The MC60 is a piece of cake to wire up and just needs some switches and a speed pot. The MC2100 is much more powerful but needs a digital PWM (pulse width modulation) signal to change speed. You can (maybe) use a doodad off Amazon, you can also buy a very reasonably priced PIC based board of our own Maxheadroom or you can use an Arduino to generate the signal based on an analog pot input.

I chose the latter because I'm cheap, stubborn and wanted to learn something new. All of which played out in this The sketch (code or program in Arduino speak) is based off of the one here https://sonsofinvention.wordpress.c...100-controller-and-lathe-tachometer/#more-389, but is a more stripped down version that George made or found.

Spent a bunch of time banging my head and grinding my teeth until I figured out what to do to compile the sketch, then it didn't work. Spent some more time banging my head and grinding my teeth until I realised the sketch and the wiring diagram differed in the switch pin. Changed that and it all worked! I set the max PWM at 950/1023 (94% of max motor speed) because over that the drive would shut down.

SUPER HAPPY!

looks like a mess because it is Next I need to see if I can power the tach off of the MC2100 board (which is powering the Arduino) and once that is done start packaging it into the drive box to go above the headstock. I realised it can't go on the motor plate as I need a reverse switch on the motor leads, so it has to all go in one box rather than a control box on the headstock and a drive box on the motor plate. WOOHOO!

 

[mattthemuppet2]

alright, drive is (mostly) complete, phew!

Control box made and stuck up on top of the headstock. It's bigger than I would have wanted but back gear handle and other stuff is still accessible.



and the finished belt tensioning lever, works a charm


some behind the scenes shots - inside the control box



the mount for the control box - cut with the boring head to match the curvature of the back gear cover, then fastened through the cover (see pic of countersinking set up!)




forward/ reverse doesn't work the way I've done it elsewhere as breaking the connection between the drive and the motor causes the drive to shut down. A fancy fix would be to use relays controlled by the arduino, but in the meantime I'll add back the switch to turn the arduino on and off. A bit more of a hassle - turn off arduino, change motor direction, turn on arduino - but alot easier to implement!

 

[mattthemuppet2]

alright, all finished.

Changed the sketch to reduce the lag in turning the speed dial and to set up a switch into the arduino so that on/ closed = PWM to drive and off/ open = no PWM. Now I can turn that switch off, reverse motor direction and switch it back on and the motor will resume at its previous speed, only in the other direction. There's a degree of motor speed ramp up so it won't be a plug reverse. Dial is nice and responsive now too.

Added a 100k pot (instead of an 18k I had lying around) which gets rid of the dead zone at the low end of motor speed where turning the dial from zero has no effect. Much better now.

Removed the spindle gear and countersunk a hole for the tach magnet, then cut out space on the gear train cover so that it would all fit.

Added a 10j poly-V belt and got the spindle all snugged up.


Also added a couple of oilers to the top of the gear box so I wouldn't have to contort myself to oil the gears in there


now I need to reinforce my work bench top and then I can get on with installing the DRO

 

[mattthemuppet2]

Reinforced the work bench and have hit a bit of a milestone - got the bed on the bench! Boy this thing is heavy. Cleaned the ways and stoned down the odd burr, then cleaned the rack, which was tedious and unpleasant.

next up is fitting the DRO

 

[mattthemuppet2]

alright, DRO is done! What a faff that was, more drilling, tapping and head scratching than I care to remember.

Had to cut the cross slide scale due to some mixed up communication, but that went fine with an angle grinder and a thin cut off disk. Tapping 4 2-56 holes in the end was a pain

the cross slide was the biggest pain. Had to countersink the way cover so I could screw it to the cross slide (had these weird "pins" before), then attach an arm to hold the read head out behind the lathe. Scale is bolted directly to the piece that attaches to the saddle plus a 3/8x3/4" bar that is also attached to that piece. It's pretty sturdy.

Finished it off with a cover for the bottom and a piece of treadmill belt to cover the slot at the top


Carriage scale was alot less of a pain, with a block that bolts to the saddle piece and a plate that connects that to the read head. I used 2 5/16" thick pieces of alu at each end of the scale to attach it to the bed as the side of the bed had a 1deg or so slope off vertical.

whole thing

readout

It's nothing fancy, but it'll serve my purposes just fine. Cost $220 for a 0.005mm res carriage scale, 0.001mm res slim cross slide scale, the readout and delivery. I'll be getting a 3 axis one for my mill when I've saved up the funds.

 

[mattthemuppet2]

pretty much done, only need to make a bunch of tool holders to start using it

all put together


back splash made


in action


apart from some ringing from a wee bit of interference between the spindle gear and gear cover, this thing is quiet.

Everything works as it should, all the feeds and the like. Looking forward to using it, I have a looong list of projects waiting

 

[Ulma Doctor]

well done Matt!!!!

 

[mattthemuppet2]

thanks Mike, I appreciate all the help you've given me. Once I get some toolholders made I'll be able to finish that tailstock extension and put it all together

 

[mattthemuppet2]

I've been too busy using this to get round to the final few projects, but I figured I'd better get off my backside and get them done. First up was making a threading dial, as it didn't come with one when new. The gear, shaft and dial were made by a friend, I just made the housing

 

[mattthemuppet2]

Also finally got my tail stock extension made - most of the parts have been sitting in a bag for two years! This was all inspired by a three part series on YouTube, I'll dig out the link in a bit. The guy provided plans and I modified then to suit my lathe (his were for a regular sb9a)

New extended nut was made from bearing bronze, using a 1/2-10 lh acme tap kindly loaned by as ulmadoc

New screw was made in two pieces - the screw was some acme threaded rod very kindly donated by ulmadoc and the handle part made by me. The two were then jb welded (I think) together.

The extension sleeve was made from solid round, threaded to fit the tail stock and cap, with clearance for the nut extension