[pianotech] Field hammer shank replacement

[paul bruesch]

After some lack of success, I recently recalled a detail that Randy Potter
teaches about the drywall screw method... apply heat to the screw until the
butt starts to feel quite warm.

And as Gregor mentions, I have found it very helpful to cut and scrape off
the glue collar before using any extraction method. In my (limited)
experience, it seems that the glue collar plays a pretty significant role in
the strength of the bond.

Paul Bruesch
Stillwater, MN

On Sat, Sep 11, 2010 at 11:45 AM, <PAULREVENKOJONES at aol.com> wrote:

>  David:
>
> That is a full and detailed answer. Much appreciated. I have yet to find
> the drywall screw solution to be effective in the majority of cases, and
> almost always cut the shank flush and drill it out.
>
> The angle of the hammer bore can be duplicated on the tail of the hammer
> and followed by eye to get it relatively close. There is always a tiny bit
> of slop in the drilling job, and this allows for more precision when gluing
> up. You can also clamp the hammer either to a neighbor or between neighbors
> while the glue sets up.
>
> Paul
>
>  In a message dated 9/11/2010 4:33:51 A.M. Central Daylight Time,
> da88ve at gmail.com writes:
>
>     I have a brad-point 7/32" bit with a hex drive end that fits
> my cordless screwdriver.  With old cedar shanks, I don't try to
> pull out the old shank; I just start drilling.  One can feel
> when the bit hits the harder maple at the bottom of the hole.
>     But with maple shanks, I use the method of first drilling a
> #39 hole into the old shank, then dribbling a few drops of
> wallpaper remover/vinegar mixture into the hole, then driving a
> short drywall screw into the hole.  Then the screw is heated
> with a cigarette lighter or mini-torch until it steams and/or
> bubbles, then the screw & shanks are pulled out as a unit with
> the shank extractor.  This works most of the time, and when it
> does, is superior to using one of the drill bit guides
> available.  But when it doesn't, then I drill it out with the
> bit mentioned above.  I keep a little bottle of the remover
> liquid, an eyedropper, & the #39 drill in a metal Band-Aid box
> in the car.
>     The butt is replaced in the action, then the new shank
> inserted and marked for length with a neighboring hammer as
> reference.  I cut it to length with a small hacksaw or Swiss
> Army knife saw blade, knurl both ends either with the sawblade
> or the edge of a file, mark which way the grain will face
> (baseball bat label theory), do a dry fit, then swirl glue onto
> the ends and after assembling, hold things in place until they
> set.
>     I'll admit I don't have a great way of duplicating the
> proper angle in the hammer molding of angled hammers and am not
> impressed with most of the jigs available.  If the old shanks
> pulls out, great -- it's already "pre-drilled."  But if it
> doesn't, you have to guesstimate as close as possible, or buy
> one of the awkward, not-as-accurate-as-they-claim jigs.  I
> usually use the shank clamp and extractor tool to pull the old
> shank out of the molding.  If too short, I saw it off flush,
> hold the molding with a Vise-grips and drill it out,
> "eyeballing" the angle.
>     --David Nereson, RPT
>
>
> ----- Original Message -----
> From: "Michael Staples" <mastaples at gmail.com>
> To: <pianotech at ptg.org>
> Sent: Saturday, September 11, 2010 12:02 AM
> Subject: [pianotech] Field hammer shank replacement
>
>
> > When you have to replace a broken, crumbly (cedar?) vertical
> > hammer shank in
> > the field, what method and tools do you use to do the job in
> > an efficient
> > and accurate manner?
> >
> > Thanks,
> >
> > Michael Staples
> > PTG associate member
> >
>
>
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