Introduction: Spinner / Jog Wheel Inside of a VCR Head

A number of months ago we were tossing some stuff out at work, included were 2 SONY security tape recorders, so I nabbed one for parts. Inside I found the usual VCR goodies including a ton of good hookup wire, a decent selection of random electronic parts, motors gears and connectors. Before disposing of the pillaged shell I decided to grab the video tape head and the bracket it was mounted on, just to make a cool spinner wheel.

And its been sitting in the bottom of my junk drawer since last summer  ...

Anyway this is hardly a new idea, but most of the time when people make these out of VCR heads they end up with a bunch of junk glued, taped, screwed, and wired to the outside of the head, making for a functional but unattractive device. I wanted mine to be as nice looking as possible (considering my limited tools and workspace) and for me that meant one thing, all the junk needs to be in the tiny space inside the VCR head

Okay then why do you want one? what does it do? Well it functions just like the wheel on your mouse, except its larger and has momentum which is good for scrolling through long web pages or piles of source code, or heck a large document.

Its also good if you do any media editing as you can scroll around in large video or audio files effortlessly, with the heaviness of the VCR head you can just set it in motion and its inertia will keep it spinning for quite a while, when you come up on something you want to work or read you just stop it with your finger.

Is it for everybody? No not really, but if you constantly wheeling the mouse in some application (and forgot the Home, End, Page Up and Page Down, and cursor keys exist) you might like it

Step 1: Parts and Tools

  • A scavenged VCR tape head and its mounting bracket
  •  A USB wheel mouse, the chip from inside the mouse must fit inside the VCR head, mine was a cheap 5$ Microsoft basic optical mouse, and the whole thing ran from 1 central chip where the camera was located (plus I didn't really like this mouse much anyway, its too light)
  •  Blank copper clad PCB
  • 1.75 to 2 inch machine screws (3 in my case to mount the bracket to the base)
  • Some washers, mainly for looks
  • 0.75 inch or 1 inch hollow spacers (I used some 0.25 inch wide 0.75 inch tall hollow hex spacers though some metal tubing would do fine also)
  • Paint of your choice
  • Resin of your choice (if you want to fill in the gap on the top of the head, I used black polyester resin, epoxy mixed with some model paint would work too)
  • A chunk of wood for the base
  • 1* LM393 (dip 8 probably would work, the one I scavenged was in a SOIC 8 package and it worked great)
  • 2* 150 ohm resistor (all resistors used were standard 1/4 watt radio shack variety)
  • 2* 470k ohm resistor
  • 2* 33k ohm resistor
  • 4* 10k ohm resistor
  • 2* 0.1uf capacitor
  • 2* infrared LED
  • 2* infrared photo-transistors
The following came from the original design of the mouse, and you need to see what your mouse would need (though I doubt it would be much different)
  • 2* 330 ohm resistor
  • 1* 1uf capacitor
  • 1* "mouse chip" (mine was marked with house numbers)
  • 1* "mystery cap" (I think its a capacitor the code on it comes up to 24 picofarad, though it also has WS printed on it which is odd)

The usual hacking stuff ... though I used a few power tools at work, you don't have to but its so much faster and easier
  • Soldering iron and usual soldering accessories
  • Wire cutters, needle nose pliers (I have this craftsman set, though mine are older)
  • Flathead screw driver
  • Screw driver or hex wrench to take your VCR head apart (mine used hex head screws)
  • Hammer
  • Hacksaw
  • Bandsaw
  • Hole saw
  • Belt sander (actually the right angle disk sander on the side)
  • Drill and bits
  • Sandpaper and abrasive pads
  • Files
  • Latex gloves
  • PCB Enchant (and in my case a old pickle jar)
  • Digital Calipers (are a huge plus, though a ruler would work)
  • Pencil / Paper
  • Hobby Knife / scalpel / Xacto (and a box cutter / utility knife if you want)
  • Rubbing alcohol
  • Multimeter (and an oscilloscope is nice but not necessary, I use this sub 20$ craftsman meter)
  • A new Sharpie or similar permanent marker with a "fine point"

Step 2: Gut the VCR Head

This is pretty easy, you need to open the VCR head and remove what little electronics are inside of it. On mine the whole thing is held together by a brass fitting on the underside, stuck in place by 2 tiny hex set screws (and thread locker), once removed the thing just slides apart.

Inside the head you will see 2 cast ferrite disks with magnet wire loops in them, this is how the head connects the spinning heads to the rest of the unit, and 2 loops act as a motor drive, its all done with magnetics and quite ingenious. Take a flat head screw driver and simply pop them out, mine was held in by a minimal mount of adhesive, though the bottom disk required a couple whacks with a hammer since it sat flat against the base of the head assembly.

Once those are removed you can see the actual magnetic heads, mine were held in place by these odd shaped star head brass screws. I tried to use a small flat head on them but they would not budge, so I went in from the side with a large flat head and hammer, bending the heads up and away from the body so I could cut them off with a hacksaw. It made a bit of a mess on the inside, but its on the inside so no big whoop.

After every thing is removed you can set the 2 halves of the VCR head aside for now, just keep track of the brass base and its set screws (zip lock type bags work well for this)

Step 3: Making the Encoder Wheel

In this project I will be replacing the mechanical rotary encoder with a optical infrared reflective encoder, in principal they both work in the same way, just using different methods. In a mechanical encoder there are 3 contacts, a common connection to power or ground, and 2 offset contacts usually referred to A and B (AB and C). If A connects before B the wheel is moving in one direction and if B connects before A the wheel is moving in the other.

Reflective encoders shine light up onto a disk, which is printed with a special pattern, directly below that disk is a pair of  photo-transistors, if one goes dark before the other the wheel is moving in one direction.

There is a website you can goto that will make all kinds of disks for you, in any shape and form you want ...

Which is awesome, but it has a couple draw backs
  1. It uses pixels as its unit of measurement, and I don't know about you but I do not have a measure that has a pixels unit on it
  2. The image it produces is quite rough on the edges which causes a little bit of jitter
To deal with number 1, I measured the inside diameter and the outside diameter of the top of the wheel, I then opened the gimp making 2 new images of those same sizes using millimeters as my unit of measurement, plugged those into the generator, and by the time I figured out its little quirks I ended up bouncing to and from the website and the gimp all in total about 4 times, checking each time with The Gimp's measure tool set to millimeters.

You can see a full size (1280x1024) screen shot of my final settings here

To solve issue number 2, I simply outlined the rough edges with a sharpie marker, finally I cut out the encoder wheel and super glued it to the top half of the VCR heads inside surface.

Step 4: Gut the Mouse

Take apart your mouse, and there is of course a board in it, before we get too happy with the soldering iron we need to figure out how this thing is hooked up. Poking around with my multimeter's continuity setting, starting with the USB plug and figuring out what pins were on what wire (never trust a color code) I was quickly able to find out what went where and made a quick drawing.

Once you know how the thing is hooked up you can desolder all the parts on the mouse, and sort out what you need from the lot, this includes ...
  • The main mouse chip / camera
  • The 24pf cap that is connected to an area of the pc marked for a crystal clock (hence the X on my drawing)
  • One of the 1uf capacitors (though I show all three, was not sure what was needed at the time)
  • And the USB cord and pcb connector
The rest of the parts ended up in my bins, the board and the mouse shell was tossed out.

Step 5: Breadboarding

Breadboarding is an important step for a few reasons.
  • Make sure I understand the circuit
  • Figure out the minimum hook requirements of the house branded (and therefore no datasheet) mouse chip
  • And to figure out how the ir part of this is going to function
First off the mouse chip is not on the same pin spacing as the breadboard, and the SOIC 8 chip is no where close, so to deal with that I used wirewrap! The larger of the 2 chips I just wirewraped to the legs of the IC, and then to a couple of pin headers, the SOIC chip I had to solder the wirewrap wire to its leads and then wrapped them to another set of pin headers. It took a little extra time but problem solved.

Next I hooked up the mouse chip with just an mechanical encoder to see how much stuff I could leave out from the design notes from the mouse, it ended up saving me 2 fairly large (in this amount of space) electrolytic capacitors.

Then I hooked up one of the IR LED's and a photo-transistor to see how that all worked and how to optimize the signal as being reflected. I had to black out the clear sides of the photo-transistor, as the IR led was going to be sitting right next to the thing and though it worked before, it was much more responsive with only the top being exposed.

On a side tangent, stupid radio shack! on the back of the IR led / photo-transistor it states the max continuous current of the led was 150ma! no way! On their website it states 40ma which is much more in line from other parts with the same spec's, I ended up driving them at 30ma just cause I happen to find 150 ohm resistors first in my parts bin.

Next the LM393 is a dual voltage comparator, you give it a reference voltage (in this case 2.5 volts though a resistor divider) and anything above that voltage is a logic high (in this case 5 volts) and anything below it is a logic low (darn near 0 in this case)

You need the comparator because the photo-transistor never hits below about 1.4 volts due to reflection of light + ambient light + printer ink does not absorb 100% of the IR light hitting it. It also never goes above about 3.4 volts due to similar issues + the resistor needed on the collector side of it to get the thing working.

Also the photo transistor is acting more like an amplifier than a switch. With fairly erratic output that shows up on a scope as a squiggly line at all sorts of voltages between the 2 extremes (so much so I could never get my scope to store an image of it), versus the square signal needed by the mouse chip. Simply put we need something to make the "yes this is on or no this is off" decision and the 393 is specifically built for the task

Finally with a working model on the bread board I drew up a "proper" schematic (full size image here)


I just noticed on the schematic I labeled the decoupling capacitors as 0.01 uf, it should be 0.1 uf, it is correct on the side list of parts, my bad!

Step 6: Prep the Parts for SMD Mounting

Since the only part I am using that is SMD is the LM393 I have to bend a lot of leads so I can mount them, I also have a couple clearance issues for fitting everything inside the VCR head

bending the leads is easy just use your needle nose pliers and bend them down then out at 90 degree angles.

The clearance issues were on the mouse chip being just slightly too tall (keeping in mind the thickness of the pcb) and was solved by taking a sharp file and filing one end down on a 45 degree (ish) angle, but don't go too deep! The second issue was the photo-transistors being slightly too tall as they have to sit at a 90 degree angle to the encoder wheel, I simply sawed off the domed part of the package and smoothed down with a file.

Yes you could just use SMD parts, but I did not want to buy a handful of components and already had this on hand, and it really did not take a bunch of time or effort.

Step 7: Make a PCB

Using the measurements from making the encoder wheel earlier I used my calipers  as a compass (which BTW is not a great idea) and scored a line in the corner of a blank PCB. I then took it to work and on a break roughly cut it out on the bandsaw.

Next I drilled a hole in the center point, through the PCB and into a piece of wood, un-chucked the bit and used it as an axle. While holding the edge of the pcb to the right angle disk sander I slowly turned the pcb getting a pretty decent round shape. For the inside hole I used a hand drill and a hole saw which was just a bit larger but fine.

Once I got home I traced it onto a sheet of paper, held the mouse chip down and made little dots where the ends of the leads were and drew little lines for the pads, then I did the same with the cord connector, then the LM393. Next I started connecting it all with lines on the paper adding pads for passive components where needed based on my schematic.

Pretty quickly I had everything in place and a very good idea (but not a final version) of how everything needed to be laid out, I then took my sharpie marker and traced over it, and circled potential problem areas due to the difference in thickness between a .7 pencil lead, and a felt tip marker.

From this point until the board is etched you should not touch it with bare fingers, so put on your rubber gloves!

Next its time to clean the board, using rubbing alcohol to wash off finger prints, and then a nylon abrasive pad to remove oxidation.

Using my pencil + sharpie test pattern I repeated the process on the board using just the marker, making minor changes in the problem areas where appropriate (sometimes its just where the marker ink soaked in the paper). Mistakes can be removed with rubbing alcohol, or with a hobby knife scraping the dried ink off the area

Once satisfied (as much as you can be with a left hander drawing a pcb with a marker) its time to etch, I placed just enough enchant in a old pickle jar to cover the board. I also microwaved a bowl of water to just under boiling (2:30 in my microwave), and then set the pickle jar in the water for about 10 min, to heat the enchant up (never heat directly). Removing the jar from the water and wiping the bottom off its now time to place the pcb in the enchant, once in I swirled it around nearly constantly, and the whole process took no time at all.

The board was removed and washed then inspected (the leftover enchant is still in the pickle jar, as it still has a few more small boards worth of power in it). Sharpie marker is not the worlds greatest etch resist but it does the trick, unfortunately I did have 1 little tiny break in a trace where it was not thick enough, and that has to be fixed (in this case with a blob of solder)

Step 8: Populate the PCB

Pretty easy since we have a printed circuit board all our parts ready to go and a schematic, start soldering!

I started by soldering the 4 places that needed jumper wires (well 3 I forgot one at first) and then soldered the chips, and so on

I did make a mistake on the PCB, there needs to be 2 330 ohm resistors in between the USB data lines of the chip and the cord, I did not leave a gap for them in the trace, but its nothing that a sharp knife and a little bit of scraping cant fix

Once done inspect your work visually, check for shorts and continuity before plugging it in, once you are sure that all is well you can put the board in place and start wrapping up. On mine I had to feed the usb cord into the hole on the side first, plug it into the board then place the board in the base. It is held in place with a bead of super glue.

You should be able to test it out, but don't button it up quite yet as there is still stuff to be done with the top half

Step 9: Paint and Assembly

So I have a working VCR head spinner, but its a little goofy having to hold it in your hand, we need something to mount it to, and that something needs paint.

I grabbed a decent looking piece of plywood, cut it to size and sanded it. Next  I held the original head mounting bracket to the wood and marked where its mounting holes were located.

I drilled the 3 holes just slightly larger than the screws diameter, flipped the board over and drilled halfway though with a bit slightly larger than the nut that I would be using so there is nothing poking out of the base and everything gets nice and secure.

Once done with the drilling and sanding of everything I used the paint booth at my work to paint the metal parts black, the wood base got a coat of sanding sealer, was re sanded again, then sprayed down with lacquer that had a cherry tint mixed in with it.

The space on the top of the VCR head tween the edge and the center hub was begging for something different (and boy I got it). Since the encoder wheel is glued to the underside its a little bit liquid tight, but not enough for polyester resin, this stuff makes water look thick! So I put a few drops of super glue down each hole and let dry overnight, once the holes were sealed I poured the resin. (sorry no pictures it had to happen very fast, but its similar to all other resin stuff, mix goop with hardener pour and pray)

At first the polyester resin was awesome looking, then the hardener started kicking in, it causes heat which goofs up the surface and a few hours later I had a lumpy top. I should have left it, you can barley tell in the pictures, but no I had to go and touch it with sandpaper ...

3 SOLID hours of sanding later, my arm was dead and my finger is still sore the next day, but it looks much nicer, had a silky smooth touch. Its not perfect, there are still a couple small dips in it, but if you care about it that much, you can sand it (that polyester is some hard stuff!)

Of course all that sanding ate up the metal in multiple directions, so I put the top in my drill and held it to my abrasive pad to make a uniform(ish) satin finish.

Assembly is pretty easy, put the VCR head back together, install the brass bottom and tighten up the set screws. Screw the head back to its bracket, use the washers, spacers and long screws to mount the bracket to the base, and your done!


PCelec made it!(author)2012-08-23

for romoval of screws like that many things kan work. tecknicaly the best way is the rigt tool else a tap and die. also for larger screww cut a slot in the head with a hack saw then just use a flat driver to remove it. i have foud that a flat screwdriver also works though normaly it will need a whack to get it firmley in. also a cheap diaginal cuter will work. take one blade and put the flat side aginst the way it will turn push down and twist, or just grab head with pliers and twist.

mgingerich made it!(author)2012-06-20

Or you could just get a set of star screw drivers. I got some at Ace Hardware for $10.

Dr+Qui made it!(author)2012-06-20

Interesting use, most end up as ready made flywheels for steam or Stirling engines, They are a lovely piece of kit to base a project on. I have one very similar to the one you used that i'm just about to start on as the flywheel assembly for a Stirling engine, need a bit of a trim down on a lathe, but i lucked out that the brass retaining thingies is already pre drilled and tapped for a accept crank shaft which came in the form of a rubber shock absorber screw from a CDROM.

Just thought of the ultimate use for this, you should use it to control the puck Arkanoid on the MAME arcade emulator it would be as smooth as the arcade machine.

wii552 made it!(author)2011-08-11

Can you use this with sony vegas, and if so, how?

didgitalpunk made it!(author)2011-08-10

my chip is damn too long. what do i do?

skaar made it!(author)2011-02-15

it may have been easier to use a protractor than a printer, mask the paper with some blue masking tape, score the paper when cutting the blacks out, and just use some gel ink. there's even space for thick card stock.

skaar made it!(author)2011-02-15

looks like a torx... perhaps something else to invest in...

pfred2 made it!(author)2010-12-21

I noticed you had some etching issues with your project. I have at times myself so I've developed a process that assures better results. Two things I have found that make etching come out a LOT better with Radio Shack Ferric Chloride are:

1. Heat that etchant up! I find somewhere around 100F makes the etchant work the way you think it should. I use a hot water bath around the etch tank.

2. Agitate the etchant with atomized air. I rigged up an aerosol agitator using an old areosol spray head salvaged off a dead spray paint can connected to tubing that I attached to a schrader tire valve plugged into one of those junky little 12 volt tire inflator compressors. This is better than rocking the tank because it introduces oxygen into the tank and aids the etching process. It may sound difficult but really it isn't it is totally worth doing.

Of course you have to brighten the copper cladding before you mask it off. But do all of this and you should enjoy perfect etches in about 2 minutes. Which sure beats playing rock the tank for 20+ minutes and getting ragged undercut traces that need sloppy repairs. Try it you'll like it.

Pretty (well my PNP mask smeared some I suck at ironing):

Etch tank and compressed air supply (before I switched to the 12V)

Another board:

I got sick and tired of ferric chloride myself now I want to try out muratic acid and hydrogen peroxide. Supposedly it is a self regenerating etchant, as in copper added doesn't saturate the solution. Though I hear dumping some sulfuric acid into ferric chloride can rejuvenate it sometimes. I've never tried it myself. Anyhow I hope you try out my suggestions. It really works!

darthmullet made it!(author)2011-01-28

an aquarium pump (<$20) does the trick rather well, too.

pfred2 made it!(author)2011-01-29

A fish tank pump is the obvious choice to use for this process but in practice they are usually harder to come by and more expensive when you do. But if you happen to have one lying around use it and post back your results.

osgeld made it!(author)2010-12-26

1) I did boil water and let the jar of enchant heat up for about 10 min, though I have no idea of its exact temp

2) I dont have the equipment to do the atomized are, though I did swirl it

I did brighten the clad up with scowering pads of fine grit, and cleaned with alcohol, and it only took about 10 min in a pickle jar swirling it around

+ keep in mind I did not use a transfer method, the only tiny 2mm spot that had a mishap was where there was a thin coat of marker, overall I think it turned out quite well for a marker

pfred2 made it!(author)2010-12-28

I've measured my etchant temperature and the acid seems to begin fuming at around 110F. At that temp it is aggressive enough.

Well that is why I left the comment. because I've swirled too and it is for the birds compared to pumping some air into the tank. Getting the equipment isn't hard, you would be better off with a bicycle pump than swirling. But shoot for an actual $6 12V tire inflator I mean splurge! OK I just looked seems like the cheap pumps run about $10 online I'm sure you can find one at a garage sale for a buck. Or ask around most men have 3 in the basement they never use.

Theoretically the best material to use to brighten copper clad prior to etch masking is Scotch Brite but I use plain old steel wool (plain as in no soap) myself then wipe with a clean dry soft rag. I suppose sandpaper would be OK too. I consider any etch that takes longer than 5 minutes to be problematic. I've cooked boards in under 2 minutes but I use air. And it isn't about the time it is about detail retention, but time is the simplest measure of etch technique success.

I used to do the exact same hand drawing method prior to the advent of personal computers and the widespread availability of free CAD software for PCB design. I wouldn't want to go back today. I use CAD for all my board layouts now, even ones I point to point wire up.

Etching a board wouldn't have helped much:

It works well:

Even with perfboard:

Worth doing.

socaldt made it!(author)2010-12-30

invest in a dremel? i wonder why those screws won't loosen up for you. i've taken vcr heads apart before. cool idea though.

adrian.robb made it!(author)2010-12-17

Mint !

osgeld made it!(author)2010-12-26


pfred2 made it!(author)2010-12-21

How come you said you could never find a datasheet for the IC?

Years of practice multiplied by massive amounts of dumb luck!

osgeld made it!(author)2010-12-26

good question, maybe I was impatient, but I just did not find the datasheet online, thanks for the heads up though, it makes it easier!

jefersonrod made it!(author)2010-12-21

Wow man, that's a real nice job, congratulations.

osgeld made it!(author)2010-12-21


VadimS made it!(author)2010-11-25

This is sweet, I built one similar a couple years ago, but it was ps/2 so it's stuck in a box somewheres.


osgeld made it!(author)2010-11-26

thanks, and maybe you should convert it =)

VadimS made it!(author)2010-11-26

My new mouse actually has something similar. Logitech g500. There is a button just behind the scroll wheel to go from clicking to free wheel. Works nicely on 100+ page PDFs. Not as much mass but with a good flick it'll spin for 10+ seconds.

For similar ideas this is where I got the info before:

ifreecarve made it!(author)2010-12-08

I'm flattered that someone remembers my work! ( is me).

This hack looks way nicer than what I put together... I just used the mouse electronics and hardware directly, so the result was really a mess of wires and awkward structure.

At the time, I was sad that a lot of people didn't go out and make their own scroll wheels out of VCR heads... but seeing this project makes me appreciate the quality vs the quantity.

Nice job!

osgeld made it!(author)2010-12-09

yes I did see yours while looking around, and almost integrated the buttons as well, though I have to admit yours is one of the nicest looking ones of the bunch

bossier330 made it!(author)2010-12-08

This is amazing. I'm definitely making one over break.

Glenn+Higgs made it!(author)2010-12-06

I don't have the knowledge to do it, but I wonder if this idea could be taken a step further to allow for up/down on the axis. This would make it into a device similar to the Griffin Powermate.

osgeld made it!(author)2010-12-07

maybe, I have never seen a powermate up close to know all of what it does, though it seems to do a bunch of it with keyboard mappings (if im not mistaken) , which would not be that difficult to replicate using a microcontroller

jrcgarry made it!(author)2010-12-04

Rather than using a printed optical pattern, you may find that a modern optical mouse is able to detect the motion of the stainless steel surface directly.

I had a similar problem to solve many years ago: detect motion of a stainless steel shaft *in vacuum* with a minimum of changes to the shaft.

A modern optical mouse, out of the box, a light sanding of the steel, and the job was done.

I can send details if needed.

osgeld made it!(author)2010-12-04

using the optical sensor though would have output XY data and not wheel data

jrcgarry made it!(author)2010-12-04

Correct - but all optical mice I've used generate quadrature datastreams

... just like a pair of encoders on a scroll wheel.

You need to find the pins (X1,X2; Y1,Y2 in the above).
Then, find how the IR wheel encoders are piped into a PS2/USB controller of some sort.
Snip the wheel encoders' tracks, and wire in the X or Y lines from the optics chip.

osgeld made it!(author)2010-12-04

see that's the issue with most brand spankin new mouses, its all packaged in to 1 chip, that was the case with this one there was only the one chip

I actually looked at 4 mouses, my GE optical, my Microsoft optical and some crap keytronix or something at work were all like that, and all were bought within the last year or so

my ~5 year old dynex had 2 chips in it, but it is a 5 button mouse and the controller chip was a dip 20 and I could not visualize how to get that joker inside the vcr head

osgeld made it!(author)2010-12-04

and yes please do post it up, I like seeing other peoples work :)

throbscottle made it!(author)2010-11-29

Those "odd star shaped screws" - they look like Torx! Number of vcr's I pulled to bits over the years and haven't got a single part of any of them - wish I had then I could make this. Cool project.

osgeld made it!(author)2010-11-29

they do look like that though I have a limited supply of funny screwdrivers, and as per most of my projects you really don't have to treat things with kid gloves

If I did it might not have a couple pits on the top metal (which were caused by a bench vice while banging these things out to saw off0 , but I would probably would still be working on it right now, and 1000X more devastated when I got a scratch on it

It just goes with "mostly hand made" I guess

throbscottle made it!(author)2010-11-29

You can get things way smaller with standard resistors if you cut the leads right off, clean the paint of the end caps and solder the end caps. I built a transmitter in a wrist watch case this way in nineteen eighty something....

osgeld made it!(author)2010-11-29

that is a excellent idea, I would say I was too lazy to sand .. but I spend 3 hours sanding down that super tough polyester resin lol

It just never occured to me, and that would make great SMD resistors in a pinch

though thanks to eyeballing angles I did not have much trouble stuffing them all in there, the weirdest solder joint is on one of the led's where "not the greatest" planning left a odd 3d s-bend in one of the cathodes

but hey I dont think it was too bad for eyeball being the only funky bend :)

spark+light made it!(author)2010-11-28

Actually, those loops on the inside are not for spinning the head, they convey data. the motor would have originally been on the bottom. (standard brushless type, 12 coils, like an out-runner.)

osgeld made it!(author)2010-11-28

on this one there was no motor attached, nor belts or anything

on this security model it only had 1 head for read 1 for write with 4 loops

read write ??? and common maybe

I dunno I am not a motor expert

handylaboratory made it!(author)2010-11-28

Regarding the pixelated output of the encoder wheel program, why not just specify a much larger internal radius and width of band, then use GIMP to shrink the resulting image. This should remove the offending noise around the edges.

osgeld made it!(author)2010-11-28

cause I don't have a printer that doesn't suck at home, and while I thought of doing something similar to get it AA, in the end it just seemed simpler to outline what I had already printed, rather than fiddle fart with the measurements again, email it to myself, print it at work (which you see are not the worlds greatest printers, but still better than my 1 good sale away from being recycled inkjet) yadda yadda etc

rusty0101 made it!(author)2010-11-28

An alternative to a drop of solder to cover gaps in traces after etching, you may be able to find a silver pen at Radio Shack that lays down silver in a paint to fill in the gap. You may even find it in coper rather than silver. It's not a surface you can solder onto very well, but to bridge a gap it won't leave a bead of solder on top of your board.

Like the Instructable overall. I edit just enough video and audio that I'm seriously thinking about making one of these.

Thank you!

osgeld made it!(author)2010-11-28

Yea I was lucky my local (40 min drive round trip) radio shack had the ir parts and a bottle of enchant lol, but that is a good tip and as small as this gap was the resistance of such stuff would not be a big deal (on top of the comparator)

Thanks and good luck if you give it a go!

alanstarkie made it!(author)2010-11-28

Looks like the job for final cut pro - I might have a go with this. An editing jog wheel made from a tape head - I like it!

osgeld made it!(author)2010-11-28

Thanks and good luck

the.texas.trucker made it!(author)2010-11-26

I'm very lost as to what this is supposed to be or what it's for.

... :(

osgeld made it!(author)2010-11-26

Its just like the wheel on your mouse, its good for quickly spinning through large documents and the like, also people who do a bunch of audio video editing like them as you can just spin your way though large compilations

Like I said its not for everyone, there is not too much middle ground on these things, its either an awesome addition to your computer, or you don't get it ... based on what random forum threads I have read

gregnjny made it!(author)2010-11-28

Thanks for explaining - I really couldn't figure it out either. Not everyone is initiated, especially coming to the big grab bag that Instructables is.

I'm not a big video editor, but as tech writer who does deal with large documents, I could see this!

As for other applications - how fine is the angular position readout on these, I wonder? Making a position sensor out of it could be useful - although, of course, that is really already what it is. :P

osgeld made it!(author)2010-11-28

depends on your encoder disk and the size of your optical sensor, on this one I am using 16 spots over the entire wheel, it could easily go to 32 with radio shack parts

foobear made it!(author)2010-11-27

Ooh, I love those VCR head things. I have one too that I couldn't decide what to do with. They have beautiful smooth spinning action and once set spinning will just go and go. Wonderful little piece of engineering goodness.

osgeld made it!(author)2010-11-27

yes they have nice machining and excellent bearings, of course the typical RMP they run at they really need to, and the mass of them helps with the weak motor drive in them, as in this one its just a couple coils inducting (and I imagine some controller magic)