modify legs for new casters

[Ron Overs]

Hello Gene,

The problem you describe is common when fitting improved castors with 
a long narrow spigot (which needs to be a moderately firm sliding fit 
in the hole to provide adequate radial support).

Since the central spigot hole needs to be reduced in diameter, if you 
plug it first, the plug will provide support material for locating 
the Forstner bit while drilling the 2 1/8" recess for the flange. You 
can drill the spigot hole after the flange recess is drilled. I use a 
Portaline drilling jig, which is a US tool, for drilling the spigot 
hole on axis with the leg. Its important that the spigot hole is 
vertically aligned with the leg or the castor will tend to self steer 
when moving the piano around (in a similar fashion to a damaged 
supermarket trolly). My Portaline jig has two holes in the base 
flange which enables the jig to be screwed to the bottom face of the 
leg prior to drilling the spigot hole. The screw mounting holes can 
be plugged with hammer shank after the spigot hole is drilled (should 
you wish to conceal the evidence).

Regards,
Ron O.

>I have been trying to modify three legs for new casters. It required 
>that I cut the legs short by 1.2 inch to maintain hight(done). In 
>addition it requires that I enlarge the existing  .86 inch hole to 2 
>1/8 inch at .25 inch deep.
>In addition the existing .86 hole needs to be deeper by 1.5+ inch 
>but it is oversize by about .085 inch.
>I have tried using my drill press and a forstner bit for the large 
>shallow hole but could find no way to secure the leg enought to get 
>it started.
>I did attach 1/8 birch plywood to the surfact to locate the center 
>and attempt to get the big bit started but the ply keeps splitting.
>Possibly my new bit from Harbor Freight needs to be better quality?
>Any ideas would be helpful.
>Gene


-- 
OVERS PIANOS - SYDNEY
    Grand Piano Manufacturers
_______________________

Web http://overspianos.com.au
mailto:ron at overspianos.com.au
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