I just joined the forum, first post, and not a "pro," just a retired engineer refurbishing my "free" petite grand piano. :)
Has anyone any experience with the Watanabe hammer boring jig? It's kind of expensive, but it looks really good.
Original Message:
Sent: 04-05-2024 07:33
From: Peter Grey
Subject: What is the best hammer boring jig to use for boring hammers with a rake angle?
I attached my Brooks fixture to a block of pinblock stock which "improved" its rigidity somewhat. While it's true that this one does not rotate on the center axis of the hammer, all you really need to do to compensate is to pay strict attention to the point of the bit as you begin boring the angled hammers (straight bore is a piece of cake), and tap the jig in the correct compensating direction as the angle increases, then go the opposite direction when you get to the bass section.
The point is that, though it can a great job, you need to really be aware of what's happening (or not happening) and this takes a bit of practice.
EDIT: And the rake angle is easily accomplished throughout.
Peter Grey Piano Doctor
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Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com
Original Message:
Sent: 04-05-2024 04:33
From: William Truitt
Subject: What is the best hammer boring jig to use for boring hammers with a rake angle?
I bought the Brooks jig sometime in the Stone Age, and mine did not come with much in the way of directions. Of course, that was before writing had been invented. :-) I think a decent jig for the money, But it was not supported at both ends, so there is too much flex for my tastes.
I have had the Renner jig, made by Dana Mazzaglia, for probably 25 years. The hammer clamp is truly half-baked. It has the sins that Chris describes.
Self-centering for the variable widths of our hammer set, is the bane of our existence for all of us. I spent about $120 for a self-centering vise, but is so inaccurate at centering straight out of the box that it sits unused on the shelf. Accurate ones cost a lot more.
Set up is a pain in the butt, so you don't want to have to do it each time you bore a set of hammers. That means buying an inexpensive new or used drill press as a dedicated work station.
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William Truitt RPT
Bridgewater NH
(603) 744-2277
Original Message:
Sent: 04-04-2024 16:57
From: Joseph Burros
Subject: What is the best hammer boring jig to use for boring hammers with a rake angle?
Hi Chris, I watched your video of the self-centering jig. Looks like it does the job. The Ragland Boring Jig has shims for hammers with different molding thickness. Not sure if the others can be compensated for that also, as I have not used them yet.
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Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com
Original Message:
Sent: 04-04-2024 10:59
From: Chris Chernobieff
Subject: What is the best hammer boring jig to use for boring hammers with a rake angle?
I've used the main commercial hammer boring jigs and both have more cons than pros. They either don't rotate on a true axis through the hammer thus as you rotate for bore angle it slightly goes off center. This is really bad on the Renner design because of the rake shelf which takes you either above or below the central axis. The other con of the renner is the feeling of working inside of a box using a little clamp. I always just held the hammer by hand which was quicker.
The other designs feature rotating back plates with a cantilevered front shelf. This always has too much flex for my tastes when made out of wood.. If that was made out of steel then that would be the way to go.
Neither of those designs really address the variable width of the hammers which means the axis of rotation is always off. I fixed that with a self centering jig. And to be fair my jig is not perfect either. Its made out of wood and i am planning on making an aluminum version. One big improvement when using any of the jigs is to use the right drill bit. Brad points flex too much, I use a mill bit which has zero flex and the holes are much more true.
https://www.youtube.com/watch?v=fdRjM9nv1UE&list=PL4km3jbQ3Am6guVzLlsW5SqDyiHCMtNJL
-chris
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Chernobieff Piano Restorations
Inventor of Inertia Touch Wave (ITW)
Advanced Resonant Compression Engineered Soundboards (ARCHES)
865-986-7720 (text only please)
Original Message:
Sent: 04-04-2024 09:43
From: Melanie Brooks
Subject: What is the best hammer boring jig to use for boring hammers with a rake angle?
Hi Joe,
I will email you some information on the Brooks LTD Hammer Boring Jig.
This is a simplistic jig which we use in our shop to drill all of our hammers.
Bore distance, Side Angle and Pitch can all be adjusted ....
Here is info, directions and photos of this simplistic jig.
Feel free to reach out to us for pricing and questions. 800-326-2440
Melanie
-- Melanie Brooks
Brooks LTD LLC
152 Rte 163 Bldg A
Uncasville, CT 06382
800-326-2440
Original Message:
Sent: 4/3/2024 2:54:00 PM
From: Joseph Burros
Subject: What is the best hammer boring jig to use for boring hammers with a rake angle?
I am new at boring hammers and do not yet own a hammer boring jig. Because the way some of my pianos are set up, I may need to bore hammers with a slight rake angle, maybe at 91% instead of the typical 90%, perpendicular angle. From your experience, which are the best boring jigs to use in order to easily bore hammer with a slight rake angle?
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Joe Burros
Cell: 646-410-7174
jbcello@gmail.com
www.fmi-newengland.com
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