EDIT - Since this page was written Ultimarc has released the Spintrak and GroovyGameGear has the TurboTwist. If you can afford one, I highly recommend them.

WARNING! Like so many projects the cost might actually end up being close to buying a pre-built unit. Of course buying one doesn't satisfy those of us who thrill in saving 10 bucks by working 20 hours and those of us who enjoy building things. If you are putting together more than two of these you might see some decent savings.

When it comes to spinners there aren't many options out there. The used market is pretty thin, Happ Controls, Oscar Controls and Slik Stik were the only manufacturers producing them and the links to projects on www.arcadecontrols.com have been disappearing. Picking up an Oscar was tempting and the new Slik Stik Tornados look nice but I needed more than one and I also was up for a project to keep me occupied in the dead of winter. The result was the QuickSpin, a low cost, homebrew spinner complete with a cheesy name and logo.

The QuickSpin was designed to be cheap and easy to assemble. Parts are about $30 to $40 and it takes under an hour to put together. It's not a polished design but it works and it'll get you started. The same goes for this web page. It is not intended to be a complete set of detailed instructions but rather as a guide. I encourage people to experiment with the design and to share their results.

 

This model of the QuickSpin interfaces with a Happ compatible optical interface like the Hagstrom Spinner/Trackball interface or Ultimarc's Opti-PAC. For those on a budget any of the usual mouse hacks will work too.

 

OVERVIEW
This version of the QuickSpin is fairly simple and mounts directly into your control panel. (I'll work on other mounting options and post them later.) There are two major assemblies to the QuickSpin - the shaft assembly and the sensor block.

 

Shaft Assembly
The shaft assembly consists of a spinner knob, some Delrin washers and a bronze sleeve bearing fitted in to a hole drilled into the panel. The shaft runs through the bearing and has the flywheel and encoder disk attached to it on the bottom side of the control panel. Shown here is a completed assembly without the control panel.

Sensor Block Assembly

An optic board is mounted on a small block of wood with some spacers to provide the right clearances. The block is screwed into the underside of a wood control panel with a #10 wood screw.


PARTS
Here's what you'll need. Most of the parts are available from McMaster Carr, a great source of industrial parts at www.mcmaster.com There's no minimum order and you can get everything on-line. Other parts are available at your local hardware store or Home Depot. The True Value down the street had just about everything else I needed. I did have to buy spacers from Mouser (www.mouser.com) but you can also get them from Home Depot. I'm looking for sources that are cheaper and will update the site if I find any.


Qty
Description
Source
Part #
Price Each
1
2" Knob
Or a 1.5" Knob
7354K13
7354K11
3.54
3.40
1
3 or 4" Hardened Steel Shaft
Or a 6" Steel Shaft
6061K411
6061K411
4.96
2.70
1pk
Delrin Washers
95647A125
7.62
1
Flanged 841 Bronze Bearing
Or a Flanged 660 Bronze Bearing
6338K451
7815K14
.63
3.64
3
Shaft Collars
6166K21
.47
1
Happ Optic Board
Or an Oscar Optic Board
Or a DIY board
15.00
7.50
3.50
1
Happ Encoder Wheel
3.00
2
Neoprene Washers
Hardware Store
.15
6+
Fender Washers
Hardware Store
.10
1
#10 Wood Screw
Hardware Store
.10
2
#4 Wood Screws
Hardware Store
.10
2
Spacers
534-409
.12

Notes:
The Delrin washers only come in packs of 50 from McMaster at $7.62 per pack. You only need about 4 to 6 of them.
Pick up a pack and share with friends.
In all the pictures below an black anodized aluminum shaft is used. A steel shaft will be silver.

Prices and Options
You can save or spend more money depending on what parts you buy. The hardened steel shafts at McMaster come in 3" and 4" lengths at $4.96 and are the easiest to use. You can also buy a standard steel 6" shaft for $2.70 if you don't mind having to cut it down. I've also used an anodized alumnium shaft with good results. The bearings come in 841 bronze and 660 bronze with the 841 being about $3 cheaper. I have yet to do a comparision. I'll try to find out what the real differences are. You also have a choice when it comes to the knobs. I've listed a 2" and 1.5" rubberized knobs but there are plenty of others available. If you go with the cheapest options the cost can be brought down significantly.
Tools
There a few tools you'll need - a set of drills, epoxy or other adhesive, allen wrenches, screw drivers and a drill press.

Building the Shaft Assembly

To create the shaft assembly we'll need to build the encoder wheel and the flywheel sub assemblies.

Adding the flywheel to the shaft
The flywheel is responsible for the feel of the spinner. Since we're going low budget, washers are used to create the flywheel. There are lots of washers out there. The ideal washer will be flat and have a hole close to 1/4" as possible. The ones I'm using here aren't the greatest. They're stamped washers with rough edges and don't stack very well. The center holes are much larger then 1/4" and I had to use a smaller washers to make sure the shaft collar had enough surface area to press down on. Choose your washers carefully.

Slip on a shaft collar and a neoprene washer onto the shaft about 1" from the top of the shaft. Tighten up the shaft collar. Add about 6 washers to the shaft. At first just add the washers to the shaft without gluing them together. This way you can add or subtract washers to adjust the feel of the spinner to your liking once you've put things together. If you can't find neoprene washers you can use rubber ones made from an old inner tube.

Add another neoprene washer and shaft collar. Center the washers and then tighten the second shaft collar while pressing it down so it holds the washers in place firmly. It's important to have the washers centered properly so your spinner is balanced correctly. An off center flywheel will spin erratically.

The Encoder Disk
To mount the encoder disk to the shaft we'll be gluing it to a shaft collar. Take a shaft collar apply the adhesive of your choice. Carefully center the shaft collar so it sits in the middle of the encoder disk. When it's centered use more adhesive to bond the two together. Be careful not to glue the set screw. After the glue sets you have a completed encoder disk assembly. Slip this onto the bottom end of the shaft and tighten the set screw.

**Since I built my spinners Happ has started to ship plastic encoder wheels instead of the metal ones. I haven't tested how well SuperGlue bonds the metal shaft collar to the plastic wheel yet.

Inserting the flanged sleeve bearing
On your control panel mark the location of where the spinner will be mounted. Make sure there is sufficient room for the optic board underneath the control panel. Drill a 24/64" hole through the panel. It's important that the hole is square to the panel so use a drill press or a drill with a press attachment. Obviously I'm not using one in this picture. You can also use a 3/8" drill but this will make the fit fairly tight. You may need to make the hole slightly larger and use a clamp, drill press or block of wood to press the bearing into place.
Clean up the hole of all debris. Take the sleeve bearing and press it into the hole. Make sure that the bearing goes in square .
Check the fit of the bearing. Use epoxy or other adhesive to set it in place. Again, make sure that it's square to the control panel!
Adding the Knob and washers.
Take the shaft and feed it through the bronze sleeve through the bottom of the control panel.
While holding the shaft assembly in place, slip a few Delrin washers on the top of the shaft. Add the knob and tighten it up. Adjust the height of the knob by adding and subtracting Delrin washers.
The spinner should turn freely. Give it a test spin and make any adjustments to the flywheel necessary. Add or subtract washers as needed and center the washers if necessary. When you get the feel you want glue the washers together. Reassemble and center everything, then tighten things down.

The Sensor Assembly
To keep things simple and cheap the QuickSpin doesn't use a mounting bracket - at least not at the moment. The optic board is mounted to a small block of wood that is screwed to the bottom of the control panel after it's positioned properly. I've shown the Happ board here but you can go for the cheaper options of an Oscar optic board or DIY board like that described on the Ultimarc site.

Prepping the mounting block
I used a scrap piece of ¾" plywood that was 2" wide and 2 .75" high for the mounting block. Using a drill press drill a hole down the center of the short end of the block to accommodate a #10 wood screw.
Drill a counter sink hole deep enough for the screw to come out the end of the block enough to screw into your control panel. For a ¾" panel - about ½". Be careful not to countersink too deep or the wood screw might come through the top of your control panel.
Take the block and place it up against the underside of the control panel. With the spinner assembly pushed down against the top of the control panel use a pencil to mark off where the encoder wheel touches the block. (You could also use a ruler to measure the distance from the bottom of the control panel to the encoder disk.)
Remove the block. Extend the line across the entire block.Position the optic board so the line falls in the middle of the sensor. Make sure the connector is on the bottom end of the block.
Mark off where the center of mounting holes are on the block. Drill pilot holes for the screws.
Using the #4 screws and the spacers mount the optic board to the block. If you don't have spacers a stack of small washers will do the job too.
   
MOUNTING THE SENSOR BLOCK
Take the sensor block and place it on the underside of the control panel. Make sure the spinner is flush against the top of the control panel. Adjust the optic board so the encoder wheel falls in the middle of the sensor slot.
   
Align the block so the optical sensor's center is in line with the shaft's center. The sensor board should be about .95" from the center of the shaft. The pictures below show how my prototypes are aligned. If you plug in the sensor you can make sure that your placement works properly. There is some "wiggle room" in the placement of the sensor.
Once you get the alignment right put a nail through the hole in the block and tap it to mark the location. Take the block off and drill a pilot hole for the #10 wood screw. Be careful not to drill too deeply or you'll go right through the control panel. Trust me on this one. You may have to disassemble the sensor block a bit to get the whole thing in place.  

Mount the sensor block on the control panel and screw it down. Realign the block and plug in the cables. Give things a test spin and make any adjustments necessary.

If you get a bit of buzzing when you spin the spinner this is most likely due to the flywheel being unbalanced. Recentering the washers and tightening up the shaft collars usually solves the problem.

Once you've got things the way you like them you can glue the washers together. You can also remove the neoprene washers and glue the shaft collars to the flywheel.

Maintenance

Bearings
Most metal bearings like a bit of lubrication every now and then. Depending on what bearing you use it may be oil impregnated and require less maintenance.

Flywheel
If you don't glue down your flywheel things will eventually spin out of place. If this happens recentering the flywheel and tightening things down will be necessary. The neoprene or rubber washers will also compress a bit and will require resetting and tightening the shaft collars.

Photos: Spinner with a 1.5" knob on my prototype control panel.  Underneath the panel. In this version I threaded the shaft and screwed the encoder wheel down.

That's about it. This should get you started on building your own spinner. There are a few areas that could use some more development. I'm looking into a longer sleeve bearing and a better flywheel. I'm also trying to find cheaper sources for the shaft, bearing and Delrin washers to bring down the costs. The same basic setup can also be used for a steering wheel. Please experiment with things and let me know what you come up with.