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Mark Fitzsimmons Mark Fitzsimmons is offline
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Default Faceplate mounting Problems

I have been turning with glued faceplates for 22 years and my
experience echoes most of the other posters here.
I use mostly titebond glue, although epoxy is often a substitute if I
can't afford to wait for days for it to dry (I have found on a 6" or
larger glue circle that some can still be wet and get a flying disk
after only 24 hours of drying). Some of my glue ups are 10-12" dia
disks and for these I usually wait a couple days or more, and
hopefully in hot sunlight.

I used to use paper as a release between joints, but find that when I
turn things over 6" dia it's no longer a good idea, and either forego
the paper (most of the time now I forego paper) or I use the tailstock
for the bulk of the turning. I find the extra work sanding or carving
off the paper is almost as long or longer than the time it would take
to part off the bowl and slice off the nub, so why put myself at risk
plus deal with glue loaded sandpaper to save a minute of time?

I have had bad luck with gorilla glue (polyurethane foaming glue). It
has failed in every circumstance, however you should know that like
Patriarch who posted earlier, I do a lot of irregular blocks that have
shock loads.

Shock loading is also a problem for CA glues, so even if you start
with a hexagon or octagon, or just the occasional catch, you can have
real problems. I use CA glue mostly for repairing cracks. In aerospace
industry it is used for holding accelerometers on a vibration table,
and when you're done with it, a little side shock is all it takes to
break the glue joint...CA is really strong in pure tension, but any
torsion or shear, it's very weak, so even with perfectly flat
surfaces, it's not a good faceplate glue.

If you can't get a good flat joint, or you have all endgrain in one of
your glue faces, two things can help: use epoxy with fine sawdust
(like from the power sander) as a gap filler and add a nice big fillet
around the joint. Turn off the fillet only when the rest of the
turning and sanding is done. (sawdust makes a good filler with yellow
glue too, but not as strong as epoxy and it shrinks and cracks, and
dries very slowly)
Second method I use a LOT when I have tall narrow vases is make a
short tenon (even only 1/2" long by 2"-3" dia works well) make mating
hole in face plate waste block and glue together. Nearly doubles the
glue surface and it's not all endgrain joint. This is especially handy
if you want to move the faceplate around on the glue block for multi
center turning, as it will hold very well off center and at angles.