Coil Winding Machine Plans - Counter Added

[etech]

Some of you saw the coil winding machine in my post about rewinding Philco shadowmeters and asked for information on how to build one. I built my machine shown here from plans I received from Gary (Radiofixer).

Winding Machine


Foot Control


Gary has given me permission to distribute his articles on the construction of this machine to those who want them. With that in mind, I asked Ed (Blacksmith) if he would host the files on his server, at least for a short period of time, so that those who wanted them could download them. Ed graciously agreed to host the files. You can find them here.

http://www.renovatedradios.com/

Just click on the downloads page and you will find the articles about the coil winding machine on that page. Then just right click on the files to 'save as' to your own computer. The first file is 5.3mb and the second is 3.7mb.

You will notice that the machine I constructed is not exactly the same as the one Gary described, but is effectively the same in principle. I just modified the plans somewhat to use materials that I had on hand or materials that were readily available to me. The heart of the machine is an 18 volt reversible 3/8 variable speed battery operated drill motor. I purchased mine on sale from Harbor Freight for about $14. I took the drill motor apart and mounted it as described in Gary's article. I made the foot controller by mounting the original trigger controller and battery from the cordless drill motor as you can see in the second photo. In addition, I purchased about $5 worth of hardware to complete the project including the 3/8" threaded rod that is used as the supply and take-up spindles, as well as the 'L' brackets and other nuts, bolts, and washers as needed to complete the project. In all, my actual cash outlay was less than $20 to build the basic machine, provided you have enough wood in your junk collection to complete the box.

You will notice a couple of additional items on my machine which were not on Gary's original version. One is the addition of a forward reverse switch up on the motor mounting bracket, to allow for easy switching of the rotation. I also needed to find a way to stabilize the reels or bobbins so that they would turn true, since all have different sized center hubs. For this, I found the black wooden balls shown on the take-up spindle in the photo above. I found them in the craft section at Walmart. It was only necessary to drill a 3/8" hole in them so they could be placed on the spindles. With these, any size center hub will be forced to be centered and run 'true' on the the spindles.

With this machine, you can put your wire reel on the supply (lower) spindle, or you can just place your supply reel on the floor between your feet for the unspooling process.

Rather than build the CMOS turns counter as Gary used in his machine, I purchased the Redington LCD Totalizing Counter from SMC Electronics for $12.50

http://www.smcelectronics.com/emod.htm

and the Door Window Alarm which contains a magnetic reed switch and a magnet for $1.99 from Harbor Freight. I have yet to implement this, but the basic idea is to mount the magnet on the take-up (motor driven) spindle and mount the magnetic reed switch nearby. The switch output will be fed to the LCD counting module to provide a turns counter for the machine. The cost of these additional parts was not included in the materials cost stated above.

LCD Counter and Magnetic Reed Switch


I built and have used my machine primarily for rewinding speaker field coils for some of my radios for which the replacement speakers are either not available, or are quite expensive. I recently used it to rewind a couple Philco shadowmeters. Obviously, there are many other uses for such a machine and I can attest to the fact that the benefits are well worth the time spent constructing it. I would be happy to answer any questions regarding the construction of the machine, if anyone decides to build it.

Ed

[Ron Ramirez]

Ed - Thank you for posting this information.

I, for one, would be most interested to hear how your mod to add the counter goes.

[Texasrocker]

Great winder Ed! Thanks for sharing this info!!

[AI2V]

I'm using the same turn counter on my coil winder.

My coil winder is an industrial 10 x 24" metal lathe with an 8 inch diameter chuck. To activate the counter I have placed a high power miniature magnet, the size of a stack of three dimes, on the outer edge of the chuck; velcro'd to the lathe bed directly below the magnet I placed a block of wood with a micro-switch (with a 1" rounded trigger arm). With each rotation of the lathe chuck the magnet brushes the switch arm and triggers a count. A magnetic window security switch was the original plan but I never got around to doing it; it would probably work better and won't break.

The magnet was used only because it can be easily removed when the lathe is used for it's intended purpose of cutting metals.

Metal lathes are fantastic if you need to rewind coils for TRF radios; mine is often used for rewinding Atwater Kent coils which require exactly 32 turns per inch with an air gap between each turn. Keep in mind that a lathe is a very dangerous piece of machinery if you don't know what you are doing. Still with all fingers.............................

[Texasrocker]

...all this info is fabulous! Thanks for sharing guys! Im looking into getting all my parts together soon to build a coil-winder for my shop. Your ideas are all genious, and very much appreciated!All this valuable info should be added to the forum as a "sticky" if its OK with Ron? Im always very-impressed by the collective "minds" at work here!! Serious radio restorers could always see the coil-winder plans here if thats OK with the inventors & webmasters? Just a idea? We would also need info on the suppliers for the magnet-wire in quantity spools,and preferred diameter(s),.. that works for different coils types application. Perhaps we could all start trying re-winding antenna,RF, IF, & osc coils as well, once the coil-winders are built individually, and owners used to working with them? Thanks again for taking time to post the photos as well !! Sincerely, Randal

[etech]

Serious radio restorers could always see the coil-winder plans here if thats OK with the inventors & webmasters?

If Ron decides that there is enough interest in this to create a 'sticky', that is fine on my end.

We would also need info on the suppliers for the magnet-wire in quantity spools,and preferred diameter(s)

Randal, I have used this supplier for magnet wire. http://www.oemwire.com/index.html His prices are reasonable and he carries a good selection.

Ed

[AI2V]

Great magnet wire site! Thanks! It looks like this wire is "solder-eze" which doesn't require stripping when soldering, a major advantage.

[etech]

Great magnet wire site! Thanks! It looks like this wire is "solder-eze" which doesn't require stripping when soldering, a major advantage.

Pete, yes it is 'solder-eze' magnet wire. I can attest to the fact that it is very easy to solder to this wire. Stripping of the insulation is not required. I just heat the wire with the soldering iron and apply the solder. Within a few seconds, the insulation is burned off, and the wire is tinned.

Ed

[Texasrocker]

Thanks again for all the info guys!! Im printing it all out for future use!! On a cold-winter weekend, these plans will come to fruition in my workshop also!! My "hats-off" to you fine folks for taking time to share all your photos, suppliers,etc!! Randal

[etech]

I finally got around to adding the counter to my homebrew coil winding machine. Here a couple of pics.





At first I did some testing to see what it was going to require for the counter to operate. It has a self contained battery which the manufacturer claims has a ten year life span and the power is permanently on. I measured the batteries in the home security alarm and found that they produce only 4 volts, not enough to trigger the counter, since it requires a minimum of 5 volts dc to trigger or reset it. So, I decided to remove the batteries from the home security alarm and use an external 9 volt battery.

I cut the circuit board traces to the magnetic reed switch inside the home security alarm detector and brought out two magnetic reed switch wires through a hole I drilled in the side of the box. I figured the original box would be a good way to mount the magnetic reed switch. It worked just fine. I just used the double sided tape to stick the box to the side wall of the coil winder.

I mounted the magnet assembly to the driven shaft by using the double sided tape supplied by the manufacturer. I decided that the magnet assembly was not secure enough, so I added a couple wraps of electrical tape around it to further secure the magnet assembly. I found the placement of the magnet assembly was not too critical, adjust it for best operation of the magnetic reed switch. I then tested the magnet assembly at the maximum speed of my drive motor, 500 rpm, and it seemed very solid, so I proceeded with the rest of the installation.

As you can see I mounted a 9 volt battery bracket to side wall of the coil winder and routed the wires to the magnetic reed switch and counter in such a way as to not cause any interference to the mechanical operation of the unit.

I mounted the counter to an 'L' bracket I found in my junk box and also added a normally open momentary push button switch to the bracket to be used as a counter reset button. I then proceeded to mount the 'L' bracket assembly to the side of the coil winder in a spot where it could be easily seen.

A test of the operation of the counter revealed that it would operate properly from a very low speed to the maximum speed of the drive motor. This counter arrangement should be very easy for anyone to duplicate. BTW, I recently saw the same home security alarm that I used in this assembly for 99 cents at my local Dollar Tree store.

Regards,

Ed

[Texasrocker]

Awesome indeed!! Thanks for the update & photos!! Im in the process of collecting all the parts needed. You guys ROCK!!