cnc winder controller board

[RedHouse]

Here's another possible transformer, 28V, 175VA, enough to run 3 stepper drivers at once.

Signal Transformer A41-175-28 - eBay (item 230378524202 end time Oct-16-09 11:19:44 PDT)

I already have mine, it just like this one 18-18V-400VA-Toroid-Transformer except mine is 20x20 @ 400VA.

I've had this one laying around (and earmarked) for just such an occasion.

These AnTek torrids are allways on eBay, and they are a great deal if you have ever shopped for a big torroid transformer you'd know.

I have some HV ones that I use in my "Studio" guitar amps, they don't throw-off as much hum as a normal transformer.

[David King]

Thanks Brad, I was wondering about those too but wasn't sure if I'd want a 12+12V or a 24+24V, I guess it doesn't matter but one would probably be a bit smaller and cheaper. I take it torroidals are smaller form and weight factor. Are they always quieter too?

I went with the $0.99 24V 100va just to see what it's like. The seller still has 15 to go I think

So those motors nema17 you got are listed as having 3/16" shafts but they were really 5mm? How long are they front to back?

[-Elepro-]

l6203 bought on ebay are all faulty..... another delay for the last test

traverse stiil mount old felt tensioner..... but i'm near finish

[RedHouse]

l6203 bought on ebay are all faulty..... another delay for the last test

traverse stiil mount old felt tensioner..... but i'm near finish

Bummer dude.

Sometimes eBay's f'shizzle, sometimes it's f'shit.
(a play on words ala; SnoopDoggyDog)

I see you have your pulley transmission in place, is it working nice?

I should have my controlers this weekend, maybe I will beat you to the final test.

I located some 6x1mm screws that should be long enough to do the deed, I will need to work out the best/easiest way to implement the traverse perhaps Lollar-style with readily available hardware store stuff.

It's too bad that parameter is not adjustable, it would have been nice if you could have anticipated different lead-screw pitches. A nice Acme screw would have been good here.

BTW, I would prefer to mount the traverse motor on the left side, same side as the bobbin drive motor, is that going to be a problem with your programming in the PIC's? it would simplify the motor-plate construction.

Having both motors on the same side would allow a single motor-plate for mounting both motors.

[David King]

Brad, I'd be interested in finding those long threaded screws. I was able to source 1m long threaded rods in M6x1 thread for about $5 ea locally but a 3 or 4" screw would be just as good.

I don't think acme threads exists in such fine pitches unfortunately but it would be easy enough to make a 0 backlash delrin nut. I did find some 1/4"-16 tpi acme, that's as small as it gets apparently.

[-Elepro-]

I see you have your pulley transmission in place, is it working nice?

it seems ok but i have not test yet with motor.... pulley on motor shaft has a set screw and the other one has "spring pin" (i don't know its english name )

I located some 6x1mm screws that should be long enough to do the deed, I will need to work out the best/easiest way to implement the traverse perhaps Lollar-style with readily available hardware store stuff.

you dont need any modification at screw... 2 6mm ID bearings at ends and a piece of rubber tube with 2 hose clamp for fix screw at motor shaft (it's the best system because it's very simple, cheap and corrects alignment)

BTW, I would prefer to mount the traverse motor on the left side, same side as the bobbin drive motor, is that going to be a problem with your programming in the PIC's? it would simplify the motor-plate construction.

Having both motors on the same side would allow a single motor-plate for mounting both motors.

not problem.. if you invert wires of a motor winding you invert rotation...

[David King]

VXB sells bearing kits of 10 pcs for $15 here:
10 Bearing 6x10x3 Sealed:Ball Bearings:VXB
these are smaller od but should hold up fine for this application.

Another option are 626 bearings, 6mm id x 19mm od. That OD is handy because it's "close enough" to 3/4" to be workable on both continents.
Then again who owns a 3/4" drill bit?

[David King]

So I measured the typical OD of some M6x1 cap screws I had sitting here and it's only 5.84mm (0.230"). That leaves 0.16mm (0.006") of play between the screw and the bearing. A couple of wraps of copper tape will make that up but it's not ideal. We can use the motor bearing at the inboard end of the leadscrew and only need one bearing at the outboard end. If I were doing it I would simply turn the head of the bolt down to 6.00mm to fit the bearing.

I like the thick rubber sleeve to connect the traverse motor to the leadscrew but I'd prefer to see that sleeve pined at both ends so that we maintain the flexibility but we don't loose any steps if things get jarred or the traverse chooses to bind up somehow.

Elepro's hose clamps will work but it's one more thing bobbing around that could catch the wire if there's too much slack. There are low profile clamps that connect with a flat dovetail at a fixed diameter, not sure where to get those. Of course a couple of turns of 12awg copper that's then twisted together at the ends and soldered will do the same thing.

[RedHouse]

...not problem.. if you invert wires of a motor winding you invert rotation...

Ahhh good.

ciao

[Joe Gwinn]

it seems ok but i have not test yet with motor.... pulley on motor shaft has a set screw and the other one has "spring pin" (i don't know its english name.

Sounds like a "scroll pin" or a "coiled spring pin": Scroll Pins, Manufacturing, Coiled Spring Pins.

But be sure that it doesn't instead expect a "taper pin": Taper Pins, Manufacturing, Spring Pins and Solid Dowels, Taper Pins, Engineers Keys.

[-Elepro-]

ciao

[David King]

I think that's what we call a spring dowel pin or a roll pin.
You can tap the hole in the pulley and use a set screw so that everything matches.

[RedHouse]

I think that's what we call a spring dowel pin or a roll pin..

+1 "roll pin"

[-Elepro-]

We haven't received our drivers yet...

not yet?

[David King]

My 24V transformer arrives today and I'll test the dragon drivers and motors asap.