Coil Winder

[CJ]

I picked up this 8 lb DC motor last Saturday at the junk shop. Should have plenty of low speed torque. Just reverse polarity to get it to spin backward for unwinding mistakes.
At first, I brought a smaller one up to the counter without a price tag and asked for a price. In order to get a ballpark figure, the manager went and got this guy shown below to compare with. The first motor was $45 and had no pulley or gizmo on the tail shaft. The second one for $65, had a 40 tooth belt pulley, and the gizmo on the tail shaft, and a mounting bracket. After thinking for a while, I decided to upgrade. The pulley can drive a mechanical counter, via a toothed belt, which is the way to go, since it won't need pain in the rear software and electronics to tell it which way is forward and which was is reverse, like an LCD display counter would. Also immune to power failures/glitches etc.
The gizmo on the end is an encoder. It puts out two square waves at 90 degrees to each other so you can sense motor direction, 1250 waves per revolution, which I think works out to 8 bits or close. Optical gradient wheel and led inside.

Speed control will be a variac into a big dc bridge, no filter caps needed.
I don't need a fancy servo system to ramp the motor up and down, and telling it when to stop. Maybe later on I can add this, but trying to keep it simple right now.

Anyway, I have the counter figured out, and I am going to buy a 10:1 precision lead screw for the wire traverse. The encoder will be perfect for driving the stepper motor that turns the lead screw.

I was hoping someone at the forum might have some experience in motor controls so they could tell me what I need in between the stepper motor on the lead screw and the encoder. I will need to tell the stepper motor how fast to click in relation to the wire size I am using. What do I need to do this?


Thanks for any help!

http://vacuumbrain.com/The_Lab/Winder/wind_1.jpg

http://vacuumbrain.com/The_Lab/Winder/wind_2.jpg

 

[yan_b]

unless you want to dive into series logic diy you can use oopic

http://www.oopic.com/

 

[CJ]

That looks totaly cool and not expensive!
Thanks!
cj

 

[CJ]

This is the company you want for a turns counter.
Mechanical D line.
170 bones for the serious models: :shock:

http://www.durant.com/f_tot.html

 

[gyraf]

Old telephone counters are very useable for things like this:

..this one is pre-settable to close a switch at a given number..

Jakob E.

 

[b2]

[quote author="gyraf"]Old telephone counters are very useable for things like this:

..this one is pre-settable to close a switch at a given number..

Jakob E.[/quote]

Hi,Jakob :grin:

Last week,I've finish a project...a Handmade Inductors winding machines,..

I've design a very simple machine to wind my own Inductor for my Eq,and so It's work pretty well I've wound my first Inductors for a Kind of Pultec Eq (22mH,200mH) thoses Have very low rcc ,very interesting,22mH Rcc=1.4Ohms with 0.3mm,and for 200mH Rcc=7.5Ohm with 0.1mm copper size.


and for counting turns ,I used a very simple electronic counter .....

HED-251-R at Radiospares,Ref:337-7139 Prices in France:14 Euros.

it's need a supply of 1.5v (Mine is a Battery AAA).

Work pretty well.

A bientot
B2.

 

[yan_b]

if you will use the oopic you can use it to drive lcd as well, basicliy its can do all the control tasks from setting the dc motor speed to counts and display turns, and sync the stepper.

(i have nothing to do with the company that sells it btw, just using one for some project)

 

[12afael]

here is a cheap and can´t be more easy counter.

http://europa.spaceports.com/~fishbake/counter/count.htm

 

[CJ]

Thanks for the counter ideas you guys!

Made some progress last night, sawed up a base and a varaic cage:

http://vacuumbrain.com/The_Lab/Winder/wind_3.jpg

Learned that it's a lot easier to wire if you don't confine yourself too much. Leave a few sides off til your done.
That's a circuit breaker/switch, saves some hassle:

http://vacuumbrain.com/The_Lab/Winder/wind_4.jpg

Scored a Jakobs 11N 3/8 in. ball bearing precision super chuck with a #2 tapered arbor. Going to have a sleeve machined to join the 1/2 in motor shaft to the 1/2 in arbor. The two diameters have about a 10 thousandths in. diameter difference, and I want a press fit so the mandrel does not wobble and screw up the coil.
110 bucks for the chuck and arbor.

http://vacuumbrain.com/The_Lab/Winder/wind_5.jpg

The DC motor needs .......um....DC, right? So I am going from the variac to a power bridge. Only need about 3 amps peak, so just a small sink ought to be fine with the 25 amp bridge. Going to add a polarity reverse switch for backing up the motor.


http://vacuumbrain.com/The_Lab/Winder/wind_6.jpg

So here is where I am so far. Thinking of putting the motor in the variac box and having the shaft come out the side. What do you think? Migh be cooler to have the motor outside. The white board will make it easier to see the small wire gauges. The motor spins pretty good. Takes 78 volts max, so I might put in a 2:1 iso trans to get more resolution and to keep the motor and rectifier happy.
The motor creeps with the variac at the full off position and no load, so I am going to have to put a small bucking transformer on one of the power leads to null it out.

http://vacuumbrain.com/The_Lab/Winder/wind_7.jpg

 

[CJ]

OK, still on this job, tried to match up the pulley on the motor shaft with something in a catalog so I could run my counter, but I figured it woiuld be easier to trash the pulley and buy two new ones with matching belt.. Plus, one of the set screws was barfed up. Couldn't get it off the shaft so out comes the Bridgeport:

Tough alloy, had to come at it from both sides to get it to do the splits:

Tapping out a lucite motor frame. DC motor has permanent magnets, don't know if a steel frame would drag out magnetism, so not taking any chances. More work than I expected, two nites worth. Lots of match drilling, tapping, counter sinking.....

http://vacuumbrain.com/The_Lab/Winder/wind_b.jpg

Two types of taps, a regular and a bottom tap. The bottom tap is the stubby one, gives you a few more threads for a fixed hole depth. Used after tyhe reg tap. You can make your own bottom tap by simply grinding the tip down on a regular tap:

http://vacuumbrain.com/The_Lab/Winder/wind_c.jpg

Poor man's counter sink, a larger drill bit:

http://vacuumbrain.com/The_Lab/Winder/wind_d.jpg

Here is the completed frame, ready for the motor....

http://vacuumbrain.com/The_Lab/Winder/wind_f.jpg

Here it is with the motor mounted:

http://vacuumbrain.com/The_Lab/Winder/wind_h.jpg

With the motor in a stiff seperate frame, I don/t have to worry about wood warping and my motor moving. Also, since I do not have my lead screw yet, I do not know where to bolt the motor. But once the lead screw comes in, it's just a couple of bolts to hold the motor frame to the base plate and I'm good to go. Also, if I want to adjust the motor height for a more comfortable location, piece o cake.

Starting to get a little excited.

We love our DIY!

:grin:

 

[Miska]

Nice work CJ!:thumb:

Since you seem to be the transformer winding guru around here I'd like to ask your opinion about these Hong Kong coil winders on eBay? Will it do the job or is it just a toy?

Anybody bought this and tried?

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=5809484638&fromMakeTrack=true

Miska

 

[CJ]

Looks a lot easier than mounting a drill in a vise. Try it out and let us know.
If it sucks, back on ebay!

 

[Miska]

Ok, I'll give it a try.

Cheers

 

[Cainester]

Boy CJ,
That's pretty swooft!

 

[Adadan]

I almost hate to send this link when you're already pretty far along with this very cool project, but you might be interested in this guy's garage sale in Los Gatos this weekend:

http://www.craigslist.org/sby/gms/107166428.html

He's got some kind of George Stevens Co. coil winder (model 410?) for sale, as well as a bunch of other electronics stuff. Not knowing much about coil winders, I searched the internet for that company and found that they make pretty hardcore looking winders--couldn't find anything about model 410, which must be an older one. Also, no mention of prices on the craigslist post.

Your DIY winder is much cooler anyway, but though I'd post the link just in case you wanted to check it out.

By the way, depending on how you end up wanting to deal with your stepper/leadscrew thing, I used a stepper for my senior project in school, and to test it I threw together a simple thing with cheap 74xx logic chips and "logic level" mosfets that would advance the motor one step per pulse, with a square wave input.

Seems like that type of circuit, plus a "divide by N" counter on one of your encoder square waves might do the trick. You could probably make the "N" in the divider variable with DIP switches, so as to make the speed of travel for the leadscrew variable. Sort of a brute force/not-too-fancy all hardware method, but possibly very cheap. If you're interested I'll try to dig up my notes on it.

 

[CJ]

Thanks for that! I might have to check it out. He has magnet wire also.
Funny thing, I think it's the same guy from across the street who moved his business out of the building. Said he lived in the Santa Cruz mountains. If it is the same guy, he's got a small gauge railroad on his property.

I was thinking an 8 pos dip switch would be enough, 255 settings possible, you could restrict the range for more acuracy. It might be a lot cheaper than designing a keyboard/computer interface.

 

[CJ]

OK, pounding in some T Nuts on the bottom of the base plate. The motor frame will bolt into these from the top.

http://vacuumbrain.com/The_Lab/Winder/wind_tnut.jpg

Two brass bolts on the frame base go into the T Nuts on the bottom.

http://vacuumbrain.com/The_Lab/Winder/wind_boltdown.jpg

Wanted to try it this darn thing out, but still needed to sneak a six pack in the back door to the machinist down the street in exchange for a steel coupling. They always leave early on fridays so I decided to make a tempeorary sleave out of lucite. Did not have a lathe, luckly this 1/2 inch drill bit fit the motor shaft and arbor perfectly. Drilling a hole all the way thru, then trim down stock into a square, then gonna grind down the edges.


http://vacuumbrain.com/The_Lab/Winder/wind_coupling.jpg

Made a sub assy with the Fwd/Rev switch and indicators.

The mill is nice for doing stuff like getting the switch to snap into the plastic, had to put a step in for those small teeth to grab that can be seen on the top of the switch.

http://vacuumbrain.com/The_Lab/Winder/wind_swplate.jpg


Couple of pre-fab led direction indicators and the plate is done.

http://vacuumbrain.com/The_Lab/Winder/wind_sw.jpg

Motor back in the frame, Fwd/Rev sw mounted on side, lucite coupling holds the chuck, just a few thousandths runout on the chuck, but the steel sleeve will probably take care of that. Ready for the counter and lead screw. Can do some hand winding the way it is now.

http://vacuumbrain.com/The_Lab/Winder/wind_full.jpg

My first coil on this thing, spinning on some hand wound stuff just for kicks.

http://vacuumbrain.com/The_Lab/Winder/wind_spin.jpg

 

[rafafredd]

Hey CJ, make me an UTC A10 clone now!!! :green:

Looking nice! :thumb:

 

[CJ]

Oh sure. Price: 10 bucks.

Psyche!

 

[CJ]

OK, I thought the long arbor looked rediculous hanging off the motor shaft, so I investigated the posssibility of hacking it in half to get the chuck closer to the motor, and also to maybe loose a few thousandths of runout. The hacksaw went thru the arbor like so many cubes of soft butter. Only the machined surfaces are hardened, not the whole shank. And when I re-mounted everything, I lost most of the runout! So now I think I can get away with the DIY plastic coupling instead of paying Joe Lathe down the street a hundread smackers for a steel coupling. :thumb:

http://vacuumbrain.com/The_Lab/Winder/wind_chuck.jpg

Also, I did some trig, and 0.001 inches of runout translates to only about 1 millionth of an inch of lateral motion.

I needed a way to get my DC volts down below the max level of the motor. At first, I thought of ading a 2:1 stepdown transformer, but then I had a bright idea. :idea:

http://vacuumbrain.com/The_Lab/Winder/wind_bulb.jpg

That 60 watt light bulb in series with the variac worked perfectly. Now, instead of 120 vdc on a 78 vdc max motor, I have 62 vdc with the variac cranked up all the way, and also better resolution with the variac knob as far as RPM control. At low speeds, the light does not glow. At full RPM's, it gives off that faint glow.

Also, an added benifit, if anything goes wrong, like my arm, or some other important part of my anatomy, gets caught up in the winding, the excess current draw from the stalled motor makes the bulb light up like a Christmas tree!

http://vacuumbrain.com/The_Lab/Winder/wind_short.jpg

This takes all the torque off the spindle until the jam is fixed. It also works as sort of a clutch, if too much tension is applied to the wire, the motor stops. This means, by choosing the right wattage light bulb for a given gauge wire, I now have an automatic tensioner failsafe. Nice to have when winding a lot of turns and something gets hung up, you have a chance of not snapping the wire if the inertia of the drive train does not take it's toll.

Also, I can switch the motor from forward to reverse at full RPM's, and the light bulb lights up durring the transition zone to sort of take the shock off the motor. Not that I would ever want to switch directions in the middle of a winding, but it can be used as sort of a brake, something that I do not have on this winder.

Anyway, thats how I roll. I'm out.

cj