This is a multi-part message in MIME format. ---------------------- multipart/alternative attachment That's just what I was going to ask you - what kind of pin are you = using? For traditional pins, I have used a drill bit the same diameter = as the pin and found the fit to be nice and tight. If yours are loose, I = would suspect a bent drill bit or somesuch. Are you doing the drilling = with a drill press with a good chuck? Have you measured runout? For = vertical hitches I use stainless steel spring pins. If I remember = correctly (it's been a while since I drilled them) you use the same size = drill bit as the pin. The pin is slightly expanded and when you pound it = in the hole, it will compress a little bit for a very nice snug fit. If you are hand drilling, perhaps that is your source for the enlarged = holes. I'm sure you could successfull epoxy a loose one in place. I = would recommend using West System resin thickened with their #404 = High-Density filler - that pin won't go anywhere. Terry Farrell Never mind. Didn't read carefully enough. I see that your drilled = the same size as the pin. Does that work out? When I've tried to drill = out for new pins it seems that the hole ends up slightly bigger than the = drill size and the pin is often slightly loose. How should it be? = Should one be tapping them into a snug fit or do you worry about = stressing the cast iron if they are too tight. Should they be secured = with epoxy? What's the approach? What type of hitch pin did you use and what drill bit size did you use = relative to the diameter of the pin? David Love davidlovepianos@comcast.net=20 =20 Recently faced the same problem on my first and only vertical hitch = pin conversion. Bass bichord hitch pins alternated fore and aft, but = still not enough space to make me feel comfortable picking a new = location. Old pins were reasonable tight, so I left them in place, = ground them flush with the top of the plate, and drilled the new holes = down through the center of the originals. 3/16 diameter (larger than = the originals at .156) and 9/16 deep (considerably deeper than = originals). Thus the top and the bottom of the new hole are in fresh = cast iron. Needed the drill press because the original pins were = harder than surrounding cast iron - couldn't push the drill in by hand. = See photo. New pins will be 3/16 x 1", with 7/16" exposed. If I set = the height of the new bass bridge cap correctly, the loops will rest = about 1/8 above the plate. =20 =20 Mike =20 =20 I'm about to drill a plate for vertical hitch pins. On the few plate = I've done this to, I've always had enough fore-and-aft room in the hitch = pin area to place the new hitch pin at a desirable location, and not be = real close to the original hitch pin. Unfortunately, on the plate I need = to drill, the hitch pin area is relatively narrow and I can't go very = far fore or aft with the new location. I can only assume that the = original steel pin is a lot harder than the cast iron and I must avoid = hitting it. Agree? Any general advice on placing the new hitch pins in a = situation like this from those who have crossed this bridge (or rather = hitch pin area) before? =20 I could go immediately aft of the originals, but that would put all = pins in one line - although the originals held up for 100 years in that = array. Should I just do that and not worry about it? =20 Terry Farrell ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/e4/21/36/bb/attachment.htm ---------------------- multipart/alternative attachment--
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