Counter Idea

[tonedeciple]

I am about to build a new winder based on Jason Lollar's. I have most of the parts already and should be up and running once I can get it assembled. For a counter, I have come up with idea that I wanted to bounce off the members here first. Basically, it consists of a thin steel wire extending out from the bobbin faceplate. As the plate turns, the wire is dragged across two steel contacts, thus completing the circuit to the counter. Would this idea work? Here is a drawing to illustrate my idea. It's sort of like a reed switch, but without a magnet.

[David King]

I tried a cam on the shaft with a micro switch. It worked up to about 400 rpm but even at 200 I think I was getting false counts. The trick is to get the dwell time as close to 50% if you can.

[tonedeciple]

How about this counter? Do you think it might be a good choice regardless of the method for tripping? It's super cheap.

American Science & Surplus : Does This Count?

[MistaT]

For best results, stay away from anything mechanical. Most of the guys are using an optical / thru beam sensor or a proximity detector.

For me, I went the proximity detector route into a cub5 counter I found on Ebay. The problem I had was that the counter input circuit was too high an impedance for the prox detector to trigger it. My solution was to put a 560 ohm resistor across the output of the proximity detector. All is well, and my counter counts way faster than what I want to wind.

One of these days when I get a chance, I will draw up a schematic for posting here, as this problem periodocially pops up here.

[JHow]

Reed switch and magnet is pretty easy and cheap. You can use one of those "window security" type switches and get a small neo magnet, all for very cheap. I paid less than a buck for the switch at a surplus store and removed the magnet from discarded toy (Awww Dad!).

[MistaT]

A reed switch an a magnet was my first attempt, and it didn't work for me. On my Cub5 counter there are two inputs, a high speed and a low speed.

On the high speed input the counter was actually counting the contact bouncing when the magnet came in contact. For example, I woould move the magnet close to the reed switch once, and it would register 5 counts.

So I used the "low speed" input, and the counter couldn't keep up with the speed of the winder.

Others may have better luck than I did with a magnetic reed switch, but the contact bounce on switch closure killed me.

[Dave Kerr]

If you're a hobby guy like me, using a bike odometer/speedometer is stupid simple, and takes about 5 minutes to hook up. Set it to wheel circumference = 1 meter and you get precision to within 10 turns, with no issues winding at the 600 RPM max of my setup. Spence had suggested this approach, and it works great for me.
Joe Gwinn posted about optimizing the reed switch approach, trick is, as David King mentioned upthread, getting the open/close cycle to be split 50/50 each rotation.

[tonedeciple]

Originally Posted by MistaT

One of these days when I get a chance, I will draw up a schematic for posting here, as this problem periodocially pops up here.

Boy, I'd really love a schematic. Even if it's just a rough sketch. I'm not fluent in electrical wiring so any help would be great. I've always thought a optical sensor would be the best approach, but I can't find a simple diagram on how to wire one up.

[MistaT]

Oh the bike odometer idea.. That's a good one!

Also in trying to get the reed switch thing to work, there was also the "duty cycle" issue, or open/close. Another problem I had, which has been alluded to earlier, is that the "on" signal needs to be long enough for everything to respond. In my case with the reed switch and magnet, the magnet would go past the switch too fast before the switch actually moved. (I think their "reaction time" if you will is 20 ms for a somewhat fast mechanical switch.)

I'm wondering about using the bike odometer (i'm guessing it has a magnet for the sensor??) how long its "on" time is?

I found on my setup that I needed my surface that the prox. detector was counting needed to be about an inch long. I also had to make the surface the same radius as it was rotating. I found that my set up was just catching the leading and trailing edge as it was spinning by the sensor (hope that makes sense..)

As far as a diagram.. Hopefully later today I will get a chance to draw something up.

[David King]

You can get free samples of most optical sensors sent to your door from the manufacturer. Fairchild made the one I'm using (QRB1114) and it was dead simple to implement. It just needs a small DC voltage (1.8-2.2VDC @20 ma) to run the infrared led and a couple of leads from the detector back to the counter. I used aluminum foil as the reflector going 1/2 way around the back of my faceplate, the other half of the track was silicon carbide sandpaper, the black stuff, it absorbs and scatters the light really well so the photodetector shows a huge swing in resistance and the counter tracks that effortlessly. The only trick was to drop the DC supply voltage from the counter from 5V down to about 2V for the LED. I used on of the online led voltage drop calculators like this one:
The Best Current Limiting Resistor Calculator for Led's You need to know your supply voltage from the counter or it's power supply, (could be 3.3, 5, 9 or 12 VDC)
You need the voltage drop across the LED which for IR leds is usually about 1.65V (It will be listed in the sensor specs.) Lastly you input the current that the LED wants for it's supply. Most LEDs are happy drawing 20ma. Enter the data and it spits out the value of the resistor that you put in series between your supply and the led. In my case Vs=5V, Led Vdrop = 1.65V, I (current) = 20ma. The resistor needed was 180 Ohm.

[tonedeciple]

Originally Posted by David King

It just needs a small DC voltage (1.8-2.2VDC @20 ma) to run the infrared led and a couple of leads from the detector back to the counter. I used aluminum foil as the reflector going 1/2 way around the back of my faceplate, the other half of the track was silicon carbide sandpaper, the black stuff, it absorbs and scatters the light really well so the photodetector shows a huge swing in resistance and the counter tracks that effortlessly.

This sounds very simple indeed. Couple of questions: What counter are you using? And, how wide is the track?

[David King]

Fairchild recommends a track that's at least .2" wide.
My counter is an old Durrant 1800. It's got presets and relays so it stops the wind at the right number. It also has a DC bus voltage of 14V to run all the outboard contraptions. There are a bunch of tiny switches on the back to set all the parameters like count up/countdown, relay reset, high speed count vs low speed count. I picked up on ebay for $15 shipped, it probably cost $500 new in 1984. What I like best is the BIG LED display I can read from across the room. very handy that.

[tonedeciple]

Originally Posted by David King

My counter is an old Durrant 1800. It's got presets and relays so it stops the wind at the right number. It also has a DC bus voltage of 14V to run all the outboard contraptions. There are a bunch of tiny switches on the back to set all the parameters like count up/countdown, relay reset, high speed count vs low speed count. I picked up on ebay for $15 shipped, it probably cost $500 new in 1984. What I like best is the BIG LED display I can read from across the room. very handy that.

Would this work?

American Science & Surplus : Does This Count?

[David King]

It should work just fine and the price is right.
I tracked down a datasheet which is probably close enough:
http://www.redingtoncounters.com/lib...ry$0@492;Entry

[MistaT]

OK, sorry for the delay, but earlier I promised a wiring diagram on how I use a Cub5 counter with a proximity detector, so here it is:



Be aware there are two basic types of proximity switches, Current sinking and current sourcing. This diagram is for current sourcing.

[tonedeciple]

This diagram is awesome! Thanks.

[tonedeciple]

So many choices, so little time. Maybe I'll try them all as it seems to be fairly low cost.

[MistaT]

Welcome!

I get a lot out of this forum. Its nice to be able to give back a little.

[CWalsh]

There are tons of people here that know way more than I do, I just thought I chuck my 2 cents in on this one. I have largely been "self trained" in the pickup winding arts. Until today, when I found this forum, I have found very little info and as a result have had to kind of figure it out myself. BTW, this forum is terrific! A group of like-minded nerds makes one feel really good. And I mean that in the nicest of ways. Anyway, I have used a reed counter from Radio Shack to make several pickups. I rigged up what I call my Ghetto Winder from an old drill and some mdf. I glued a magnet to the winding spool and mounted the reed counter to the supports. The leads run back to an old mouse and I use the calculator function on the computer. If I really rev the drill, the counter misses some counts, I just don't go full speed. Compared to the sweet rigs that I've already stumbled on here, mine is way more ghetto than I even thought. However, it works and since I mount the pickups in guitars that I build, and I only build a half dozen a year, half the fun is showing people my "hi-tech" equipment.

Thanks already for the forum. You guys make me feel like I was blind until today.

[MistaT]

CWalsh,

Welcome to the forum! I too am a noob here, but I totally get what you are saying. As far as nerds go, I'm coming to the realization that nerd is in fact the new cool.

You are right, this forum is amazing! As in there are true experts who really know their stuff.

Your ghetto winder sounds alright by me! As is often the case, there is more than one way to do things. My winder is pretty ghetto too, its an old sewing machine with a desk lamp on top that is held on with a bungee cord! Honestly I'm really feeling like its not complete b/c it doesn't have any duct tape on it.

[tonedeciple]

When I started winding my own pups, I used a so called ghetto winder as well. I used a pedometer/reed switch to count turns and when that failed (as the always seem to do) I timed and tested with a multimeter.

Now, however, as requests for pups have increased, I found myself needing a more reliable way to count turns for the sake of consistency. Then, a friend of mine offered to buy me a winder if I'll make him some pups for free. It's a good deal for both of us. I get a winder and he gets a bunch of custom pickups made to his specs.

I still plan to make a winder using the advice in this thread. If I start getting more requests than I can handle alone, I put my son to work with the homemade winder.

[David King]

Have you considered the CNC winder that a bunch of us are making for ourselves based on a PIC controller that elepro has programmed? There are a few hundred posts to read but the cost is probably less than an out-of-the-box schatten winder.

[Mathen]

On the subject of "ghetto winders" that was actually what I named my first winder. It was a ten dollar universal motor with part of a tap and dye set stuck on the shaft sticking out a metal mail box. Believe it or not... it worked pretty well, I just didn't have a counter so I've built a few new ones since.

I'm going to have to find a picture because it said ghetto winder on it big as day. My kids thought it was hysterical.


Edit: Gah, I found a couple of pictures but they were before I Christened it with orange paint pen. So now I've gone and de-lurked with an amusing anecdote that isn't nearly as amusing without the visual gag. I'll go ahead and post a photo of it anyway, because it really did wind a couple of decent (if inconsistent) pickups before I made winder II.

[tonedeciple]

Originally Posted by David King

It should work just fine and the price is right.
I tracked down a datasheet which is probably close enough:
http://www.redingtoncounters.com/lib...ry$0@492;Entry

I'm thinking out loud here so bear with me. It looks like this counter doesn't have DC supply output. Therefore I'm guessing I'd need and external power supply for the LED. Then I would connect the sensor side of the QRB1114 to the inputs on the counter. Does that sound right?

[David King]

Yeah just a dc wallwort or a couple of aa cells.
The Fairchild(1114) thing I linked to is a phototransistor. You can try it out and see if it works like that or you may need to build some sort of amp. There are guys here that actually know something about electronics and can read the datasheets for you an tell you if it will work or not. You can also call the companies involved and ask for tech support.

[BizzarGuitars]

Has anyone else tried the applications at this site?http://pickups.myonlinesite.com/programs.php

Using the serial port on a computer, a reed switch and a small magnet, makes it really easy.

That web site also has a Pickup Calculator application for approximating number of turns and total resistance depending on bobbin dimensions.

[-Elepro-]

Originally Posted by tonedeciple

I'm thinking out loud here so bear with me. It looks like this counter doesn't have DC supply output. Therefore I'm guessing I'd need and external power supply for the LED. Then I would connect the sensor side of the QRB1114 to the inputs on the counter. Does that sound right?

it works.....but first of all you have to find a wallwort and say its tension..... then QRB1114 needs a resistors on the anode of led..... and another one on the collector of sensor...

[tonedeciple]

Originally Posted by -Elepro-

it works.....but first of all you have to find a wallwort and say its tension..... then QRB1114 needs a resistors on the anode of led..... and another one on the collector of sensor...

This is a wall wart I found:

12 Watt 12 VDC Power Supply

Question is, how do I connect it to the QRB1114 and then the QRB1114 to the counter?

[David King]

Try your local Goodwill store for a wallwart, you needn't pay top dollar + shipping for a $1 item. Everybody has piles of these things lingering around the house anyway.
9VDC is probably fine but a 5VDC would be even easier I think and it could probably supply the counter as well.

[-Elepro-]

Originally Posted by tonedeciple

This is a wall wart I found:

12 Watt 12 VDC Power Supply

Question is, how do I connect it to the QRB1114 and then the QRB1114 to the counter?

bye

[tonedeciple]

Originally Posted by -Elepro-

bye

Sorry to be a pain, but does this look right based on your schematic?

[-Elepro-]

yes...

the blue wire go to input+ and the green one at input-

bye

[tonedeciple]

Originally Posted by -Elepro-

yes...

the blue wire go to input+ and the green one at input-

bye

Thank you so much!! It's been a long time since I breadboarded anything so I wanted to check with you first.

Now here's an idea for your CNC winder. It's an automated potting method. With about 60-70% of the wind complete, the winder would slow to about 100rpm. Then, a servo would open a tiny valve and release a drop or two of water-based polyurethane onto the coil. Capillary action would draw in the poly and after a few turns, the winder would return to speed. At the end of the wind, the winder would slow down again to allow another drop or two of poly onto the coil. No more messy wax potting! Here's a simple drawing.

[David King]

For the potting idea I'd suggest wicking the material directly onto the wire as it passes onto the bobbin. That shouldn't be too hard.

[tonedeciple]

I'm about to order my parts, but I found a wall wart rated at 3.0VDC/400mA. What would the new R1 and R2 values be? I realize there are online calculators for this info, but I can't tell from the spec sheets what numbers to plug in.