# Biscuit Joiner Technique-Questions



## gerrym526 (Dec 22, 2007)

Haven't used my biscuit joiner for a while, and now will be using it for carcass joinery on a current project. I went ahead and did some research at FWW.com and other sites. Came up with the following questions I need help with-

1) Open time once the biscuit touches the glue-how much time on average will I be able to tweak or manhandle the joint. Or looking at it another way, how long before the biscuits swell to the point where the joint can't be adjusted?
2) Glue on biscuits and slots only? Or across the face of the boards being joined?- In looking at articles on the topic there seems to be two schools of thought.
3) How long to leave clamps on the joint?-Again, think carcass construction (tops/bottoms with sides and middle shelves/dividers). Normally, joints I glue stay in the clamps a minimum of 4hrs, but some articles have said once the biscuits swell the clamps can be taken off after 30min to an hour.

Thanks for the help guys.
Gerry


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## SnowyRiver (Nov 14, 2008)

If you use a yellow glue like Tight Bond, you will only have about 30 seconds to position the biscuts before they will start to swell and become difficult to move or remove from the slots. You will have a bit more time attaching the second piece though since the biscuit is dry at the top and gives you a bit more time. I always put glue in the slots, and along the entire joint on both pieces.

For clamping, I think you could probably remove the clamps in about 30 to 40 minutes, but I usually leave them on for a couple of hours to be safe.


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## Sawkerf (Dec 31, 2009)

When I'm using biscuits, I like to dry fit each joint before glueup (sometimes a slot needs to be recut to get alignment). Then, I set up my clamps and move fairly quickly through the glueup putting glue in each slot (both boards) as well as between slots. Depending on the number of boards I'm gluing up, I sometimes draw everything up before adding more boards. Sometimes - when I doing several longish boards - I'll do two halves, let them set up, then glue them together.


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## reggiek (Jun 12, 2009)

These guys got you covered pretty well on the glue up…...but I wanted to weigh in on the full joint gluing. I do not think it matters to the bisquit whether the whole joint is glued or just the bisquit and slot (as far as it's ability to reduce shift) - The bisquit is really more for alignment then for strength in my opinion….it is having the whole joint glued that gives stability and strength to the joint….without a full glue line, all the stress is being handled by each bisquit in turn (leaving gaps).......unless you bisquit the whole length like a slot tenon…As for clamp time…I am always of the opinion that the more time I can get the glue to cure under pressure (up to 24 hours max) the less chance I will have a failure due to inadequate curing time.


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## gerrym526 (Dec 22, 2007)

Guys,
Thanks much for the input.
Have a question or two for those of you who glue along the entire joint surface.

1) How do you prevent a significant amount of glue squeeze out?
2) Do you use one of those special biscuit glue applicators that fits the slot and dispenses the glue, or just squeeze out of the bottle?
Thanks
Gerry


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## SnowyRiver (Nov 14, 2008)

Gerry,

There will be some squeeze out. What I do is I have a small brush. I squirt the glue along the edge then use the brush to distribute it evenly including getting glue in the slots. I have tried the roller bottle, but I dont like it. I find the brush works better. Once clamped, I take a damp rag and wipe the excess glue off. After its dried I just use a sharp scraper and remove the rest, then sand it.


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## DerekL (Aug 18, 2008)

The way to avoid 'significant' squeeze out is to not put too much glue on the joint. You do want a little squeeze out because that's your indicator the joint isn't starved.


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## Sawkerf (Dec 31, 2009)

I use Titebond right out of the bottle and the tip works great for squirting glue into the slots. Between slots, I run a small bead and spread it with my finger (which is then wiped onto my jeans - lol)

The quantity of glue is really subjective. I shoot for just enough to get a small amount of squeezeout all along the joint with moderate clamping pressure. No, I can't define "moderate", but I know it when I feel it. - lol


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## reggiek (Jun 12, 2009)

I also apply some painters blue tape (or you can use masking) along any exposed edge of the joint (the inside or unexposed area can be dealt with by sanding or scraping as Wayne has indicated….but the outside I try to keep free of glue so that I won't have any problems with the finish not applying evenly (especially if both sides of the joint are relatively finished and you don't want to spend alot more time sanding)). Put the tape on and then apply the glue…once the glue has set…you can pull the tape and the glue right off….


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