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Glue Plates THEN Drum Sand? Drum Sand Then Glue?
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Author:  LarryH [ Tue Jan 15, 2013 11:46 am ]
Post subject:  Glue Plates THEN Drum Sand? Drum Sand Then Glue?
Not sure if I should thickness sand my new black walnut back plates then glue or glue them first? Maybe plane close, glue, sand? Glue, plane close, sand?
Author:  Pmaj7 [ Tue Jan 15, 2013 11:59 am ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
Plane to about .030" of final thickness (.020" if glued face down, you feel confident and plates are flat), glue, sand. (Make sure show face is smooth)
Author:  ZekeM [ Tue Jan 15, 2013 11:59 am ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
I'm a believer in the sand to just above desired thickness, join halves, cut rough to outline, finish sand to desired thickness method.
Author:  Ron Belanger [ Tue Jan 15, 2013 12:01 pm ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
I like to have my top and back plates about .188 inches or so when I glue them. If it's a nice straight grained wood I will use my planer to bring them to that thickness, glue them and then to the sander. With highly figured woods I will joint the edges, glue them and start with coarse grits (30 or 60) and thin to around .188 inches and then switch to the finer grits (80 and 120) to final thickness.
Author:  theguitarwhisperer [ Tue Jan 15, 2013 12:21 pm ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
I like to glue them thick simply because they're stiffer, although I 've joined them at final thickness and had no problems just scraping the joint smooth and then bracing.
Lately I like to sand them smooth, joint them, and then install the backstrip or whatever if the plan calls for it, sand it to final thickness in the sander, cut out the shape, brace it.
Author:  LarryH [ Tue Jan 15, 2013 2:04 pm ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
All righty then. Looks like, as usual, there's as many ways to do this as there are people doing it.

Thanks for so many responses, not sure which way I'll go but probably glue, plane close, sand. We'll see.
Author:  mqbernardo [ Tue Jan 15, 2013 4:18 pm ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
so far i´ve only glued rough plates - i might scrape them before jointing to reveal the grain if it´s too fuzzy. i find it easier to have a larger glue surface. then comes the plane, then sanding.

might try to thickness them a bit first, shouldn´t do any harm.
Author:  Tom West [ Wed Jan 16, 2013 7:06 am ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
Anyone who read my erased post please disregard....!! Quite obviously made before coffee and while my brain was half asleep.
Tom
Author:  Fred Tellier [ Wed Jan 16, 2013 9:38 am ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
I use the tape method of joining and it makes it difficult to clean of the squeeze out so joining at around .150" allows a good clean up with the thickness sander.

Fred
Author:  jfmckenna [ Wed Jan 16, 2013 9:48 am ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
I like to join the plates as thick as possible. Room for error plus shooting the boards thick seems to work better. I cut the outline then thickness through the drum sander.
Author:  LarryH [ Wed Jan 16, 2013 9:49 am ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
Thanks for all the ideas. I had one back plate at ~.155 and the other at ~.140 I sanded the thicker to match the thinner and glued them up (tape method as well). Today I'll final thickness to around .095 for this parlor sized back. Really helpful and another thanks to everyone for their input.
Author:  Mike OMelia [ Wed Jan 16, 2013 10:22 am ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
Glue, then sand (at an angle to avoid glue line build up on paper). If incorporating a back strip, do a little sanding first, rout and install, then final thickness sanding. I use the Spanish joining system. I do not care about glue squeeze out (though I will do my best to clean what I can). It all scrapes off without a problem.

Thicker plates are easier to join, you can safely use more joining force. If you use final thickness plates, any uneveness (unexpected) will require more sanding and perhaps you end up with plates that are too thin. A backstrip that is routed into the seam results in a much stronger joint than a backstrip joined between two plates. DAMHIK. Finally, I don't fully understand why, but sanding joined plates results in a more "invisible" joint.

Mike
Author:  Link Van Cleave [ Wed Jan 16, 2013 10:39 am ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
Should be mentioned (maybe someone did I didn't read that carefully) that you should only do just enough sanding/planing/ flattening as necessary on the show side . For stock removal or thinning do that on the non show side so you don't lose the pattern of your book match. How much this matters varies with different cuts of wood etc. but it is a good general rule to follow.
L.
Author:  Mike OMelia [ Wed Jan 16, 2013 12:11 pm ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
No, it wasn't mentioned Link, and that is a very good point. [:Y:]
Author:  LarryH [ Wed Jan 16, 2013 3:11 pm ]
Post subject:  Re: Glue Plates THEN Drum Sand? Drum Sand Then Glue?
jfmckenna wrote:
I cut the outline then thickness through the drum sander.


Yeah cut the outline, then final thickness. Just makes that much less material to send through the sander. I cut the shape after sanding to final. Not the best way IMO.
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