Posted by peahix on May 11th, 2009
Removing the idler wheel from the Optigan is a challenge, but can be done if you are patient and mechanically inclined. If not, you may want to solicit help from a mechanically savvy friend to work with you (and share the pain). This will be a learning experience, and potentially frustrating if you are not careful. Or it could be a Zen experience that will increase your love and intimacy with your instrument (but this is very doubtful). Old Optigans tend to be dirty inside, so protect your floor with a drop cloth. Make sure you have plenty of light, maybe a flashlight too. Since the Optigan I bought from Pea needed some restoration, I've had it apart several times, so it wasn't too painful for me to remove the wheel and wheel shaft from the machine. It did take a few hours. You may want to get the technical manual CD for your model from Pea so you know where all the screws are, and the proper order to remove them. On some models there are a few hidden screws, and the manual will show these. One of the biggest challenges you'll face if you've never had your unit apart is removing the sides (assuming you have one of the units made of the plastic Temperite material and not the all wood model). The sides tend to glue themselves onto the main section, and it can be hell to get them off. You may need a rubber mallet to separate them after you remove the screws that hold them on. You'll need small and large size Philips screwdrivers as well as a slot blade type. Nut drivers or a socket set is helpful, but remember this is an old American-made product, so the sizes are in fractions of an inch, not metric (Darn those Americans!) As you remove screws, I recommend putting them in little baggies and labeling them so you know where they go, as well as a sequence number (e.g., "Step 1, back panel screws"). You'll thank yourself later that you did this. If you take pictures with a digital camera of each step, you find this helpful as well (and you can send them to us to upload to the web site to help others!) Take care not to break wires, and don't use too much force. I found that I had to remove the electronics on the top of the chassis to get to the wheel as well as some of the keys on the keyboard (there are hidden screws underneath some of the keys.) I had to loosen the motor housing too. In fact, I recall completely removing the top chassis from the Optigan to get to the wheel. There is a small spring that goes towards one end of the idler shaft; note its position and take a picture or make a drawing so you can reinstall it later. You have to fish the shaft and wheel out as a unit after removing the retaining clip that holds the shaft to the mechanism. Don't attempt to remove the wheel from the shaft. On some units the wheel is held in place by a clip that is easy to break or lose. In other units, the shaft is crimped on either side of the wheel, which would have to be ground down. But removing the wheel from the shaft should not be necessary because I've talked to the guy who restores the rubber and he said he would take care of that part (or at least give it a try). He may charge a bit more if you leave the wheel on the shaft, so you'll need to inquire with him directly on price. While waiting for your wheel to come back, you should clean and lubricate your Optigan. Use a vacuum to get all the dirt and use an all-purpose machine oil to lubricate the flywheel shaft and motor (avoid getting oil on the flywheel rubber). Just a drop of oil on the pivots and linkages is enough. I washed the keys in the kitchen sink. When you get the restored wheel back, put a drop of oil on the wheel bearing. Now refer to your notes and pictures and reassemble your Optigan.