Pinblocks are not that mysterious, just tedious and detail oriented. First take every conceivable measurement you can. String heights, bearing all over, plate height, plate location from stretcher and rim and block height. Think through this, beginning to end, write down the procedure as you perceive it and add to that or rearrange it as you think it through. Have a plan, work the plan and change it as you learn more. Next drill two small (3-4/32") holes through the plate and into the old pinblock. One in the bass and one in the treble. These holes are your main orientation from this point on. Carefully measure, after plate removal, the distance from the center of the holes to the rim and to the stretcher and write them down on the keybed. Carefully measure the thickness of the block material. Order the new block and have it thickness planed to you dimensions by the supplier, unless you have a thickness planer. Precision cutting will be needed here on. Layout the primary cut, the shape of the plate edge but remember, that cut is at a three to five degree angle so you must account for this plus the fitting removal of material. Here you need a band saw. Tilt the table at the proper angle and make a test cut and match it to the cut you need to make on the block. You will need an air driven grinder/sander with 40 or 50 grit disks. Home Depot or similar have these items. Get the disks made for this tool, don't cut your own. Paint the plate (your choice of chalk, graphite, or other) and lay the block into plate and MARK it's location. Hit it will a rubber mallet so you have marks and grind off the marks until you get a nice fit, top to bottom left to right. Clamp it in place and drill the holes through the plate and into the new block. Lay out the lines, and angles, on the new block from the holes. at the band saw cut the width and length of the block and fit it into the piano. Finish the fit with a power planer or a good power sander. Double, and triple check everything. At this point you need to decide if you are going to bore the block in or out of the piano. If in then just glue it in and mount the plate. If out then you need to put the block onto the plate with three or four screws and center punch each pin hole and the other screw holes. Use a red or blue pen to mark the screw holes so you know what to bore for. The angle o f the bore is determined by measuring the angle to the plate where the string goes from 1/8" off the plate to the riser or aliquot bar, between 2 and 5 degrees. What you want is the string coming off the pin perpendicular to the pin when the bottom coil is 0.125". Very simple and uncomplicated. You should use a cut off piece of pinblock and bore holes of different sizes, F, G, 17/64" and pins from the set you will use, mic those and write the sizes on the block. Drive in the pins and use a torque wrench to torque each pin and write that on the block of wood. Allow to lay around as long as you can and check the torque as often as you can. Pick the bit size you like for the pin you like and go and buy five of those bits, all from the same manufacturer, the same lot, and change the bit every 50 holes or so. Feed speed is important; fast drilling makes a smaller hole and slow feed makes a larger hole. Feed speed is critical for best feel. Mic all the pins and arrange them in order, fat ones in the bass and skinny ones in the treble. Just don't touch the threads with sweaty or greasy fingers. The rest of the work you should be familiar with. If not scream here. -- Newton Hunt Highland Park, NJ mailto:nhunt@jagat.com
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