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Re: Strip: Butt joint issues?
By:Bill Hamm
Date: 12/29/2010, 8:16 am
In Response To: Re: Strip: Butt joint issues? (Charlie)

: 8:1 scarfs shouldn't break just from handling. Scarfs have been
: around from, at least, the days of the Romans, and they wouldn't
: have lasted that long if they crumpled so easily.
: A proper scarf demands a bevel be cut across the broad face of a
: plank to give good gluing surface so that the face of the bevel
: should be X times the thickness of the wood. If you cut your
: bevel any other way it will be weak.
: You can line butt joints up any way you like but the eye will be
: drawn right to them if they are too close together. Why bother?
: it's no more work to distribute the butts randomly over the
: hull.

: Hi all,

Doesn't matter, an 8:1 scarf is an 8:1 scarf, doesn't matter in the least if it's thru the width or thru the thickness. I've done a whole bunch of thru the thickness scarfs on 1/4" plywood, works just fine. Yes it looks like the joint would be smaller, it's not, it's identical in area. Scarfs though are all end grain, the end grain is a sponge, sucks up glue like crazy. I do my scarfs in epoxy but suppose it'll work with regular glue too, but same problems exist, you have to pre-coat the glue lines, to seal the wood, let it set up, then glue the joint. Otherwise the end grain sucks the glue out of the joint and you get failures.

The advantage to doing scarfs with thickened epoxy is it's great gap filler and most wood glues arn't. Scarfs are difficult at best to clamp so when using conventional glues you have to figure out a way to make a secure clamping method to get reliable joints. Wtih epoxy fairly light pressure works fine, so just weighting the joint works file as a clamp.

Bill H.

Messages In This Thread

Strip: Butt joint issues?
Darel -- 12/28/2010, 10:03 pm
joints of many kinds *PIC*
Paul G. Jacobson -- 1/2/2011, 12:02 pm
Re: Strip: Butt joint issues?
Fred Gasper -- 12/30/2010, 7:57 am
Re: Strip: Butt joint issues?
Paul G. Jacobson -- 12/30/2010, 11:54 am
Re: Strip: Butt joint issues?
G New -- 12/29/2010, 8:07 pm
Re: Strip: Butt joint issues?
Eric -- 12/29/2010, 7:14 pm
Re: Strip: Butt joint issues?
Rob Macks / Laughing Loon CC&K -- 12/29/2010, 2:16 pm
Re: Strip: Butt joint issues?
Dean -- 12/29/2010, 12:40 pm
Re: Strip: Butt joint issues?
Joy -- 12/29/2010, 9:43 am
Butt joints NOT over forms are bad
Paul G. Jacobson -- 12/29/2010, 1:43 pm
Re: Butt joints NOT over forms are bad
Al Edie -- 12/30/2010, 12:06 pm
Re: Butt joints NOT over forms are bad
Bill Hamm -- 12/30/2010, 1:48 pm
Re: Butt joints NOT over forms are bad
Bill Hamm -- 12/29/2010, 3:02 pm
Re: Strip: Butt joint issues?
Randy Echtinaw -- 12/29/2010, 10:56 am
Re: Strip: Butt joint issues? *PIC*
Joy -- 12/29/2010, 10:09 am
Re: Strip: Butt joint issues?
Bill Hamm -- 12/29/2010, 8:28 am
Butt joint boards or strips? *PIC*
Jay Babina -- 12/29/2010, 8:19 am
Re: Butt joint boards or strips?
Bill Hamm -- 12/29/2010, 8:30 am
Re: Strip: Butt joint issues?
Bill Hamm -- 12/29/2010, 8:07 am
Re: Strip: Butt joint issues?
Les Cheeseman -- 12/29/2010, 5:03 am
Re: Strip: Butt joint issues?
Randy Echtinaw -- 12/29/2010, 7:00 am
Re: Strip: Butt joint issues?
Darel -- 12/29/2010, 5:36 am
Still got that bottle of glue?
Paul G. Jacobson -- 12/31/2010, 7:22 am
Re: Still got that bottle of glue?
Darel -- 12/31/2010, 11:31 am
buy new glue
Paul G. Jacobson -- 12/29/2010, 4:27 am
Re: Strip: Butt joint issues?
Dave Houser -- 12/29/2010, 12:46 am
Re: Strip: Butt joint issues?
JohnK -- 12/29/2010, 2:23 am
Re: Strip: Butt joint issues?
Charlie -- 12/28/2010, 11:20 pm
Re: Strip: Butt joint issues?
Bill Hamm -- 12/29/2010, 8:16 am
Re: Strip: Butt joint issues?
Allan -- 12/28/2010, 10:36 pm
Re: Strip: Butt joint issues?
Stephen Troy -- 12/28/2010, 10:13 pm
Re: Strip: Butt joint issues? *NM* *PIC*
Darel -- 12/29/2010, 12:43 am
Re: Strip: Butt joint issues?
Bill Hamm -- 12/29/2010, 8:33 am
Re: Strip: Butt joint issues?
mark j -- 12/28/2010, 11:19 pm
Re: Strip: Butt joint issues?
Darel -- 12/28/2010, 10:22 pm