I'm probably the last to know...

[David Rose]

but do you know where the glue goes when the tenon and mortise are a nice *tight* fit with no clearance groove? Did you know that a tight mortise and tenon make a great hydraulic pump with glue as the medium? So what is the escape route of least resistance? The side wall of the mortise of course! It takes very little clamping pressure to blow the glue out the sides of 1/4" thick walnut. I think it will clean up OK, but it was a bit of a surprise. It shouldn't have been but I can be a slow learner.

David

[Bobby Hatfield]

[QUOTE= It takes very little clamping pressure to blow the glue out the sides of 1/4" thick walnut.

David[/QUOTE]



Hey David, did the walnut crack ? Hope it will go back in place ok, at least you should have had enough glue in the crack. I really hate to have to repair as I build a piece, don't you.

[Bob Lasley]

One thing about it, you won't forget this one. I generally cut my mortises about a 1/16th deeper than my tenon is long. I also like to have my joints be a slip fit when they are dry, ie. no hammering to get them together.

Bob

[Dave Anderson NH]

Always make your mortise slightly longer than the tenon or vice versa if you are like most of us and chop the mortise first. It also helps to take a chisel and slightly bevel the last 1/8" or so of the tenon so it will fit easier and the end doesn't split. Remember that you only need glue on the four sides of the tenon, glue on the shoulders is useless because it is end grain and all it does is squeeze out and require cleanup. Glue on end grain provides almost no strength.

[Charles McKinley]

you should box up that FMT and send it to me before anymore of these unfortunate accidents occur! LOL

I hope you can save it.

[David Rose]

Bobby, yeah it just cracked the wall. And there *was* glue in the crack! Glory be! ;-) I caught it when it occured so I could squeeze the sides back down before setup. Just a little extra scraping/sanding...

Bob, nope! I won't forget. That was kind of amazing to watch. :-( I did have about 1/16 end clearance but no other. And they didn't have to be hammered together. The power of a Bessie did a fine job. ;-)

Dave, I do understand about the gluing principles. Thanks for the bevelling tip. I had forgotten that one. I just kind of "squooshed" the glue in without enough thought. If the piece needed glue strength, it wouldn't have much because I suspect the tenon faces are pretty "clean". :( The main thing I did wrong was too snug a fit. But I suspect that bevelling the tenon end will help not scrape the glue off the sides too.

Charles, I should send my Bessies too as they were involved in the conspiracy against me. ;-)

The next set of tenons I adjusted for .002" on tenon and mortise and suction will hold them after a gentle push (hand) together. Now to make sure the "hydraulics" are not overloaded. ;-)

David

[Bobby Hatfield]

The next set of tenons I adjusted for .002" on tenon and mortise and suction will hold them after a gentle push (hand) together. Now to make sure the "hydraulics" are not overloaded. ;-)



David, you mean to tell me that FMT is that adjustable ? Its about time for a review with pictures.

[Dave Arbuckle]

Bobby, the adjustment knob has eight numbers on it. Each number is .002" overall change, a thousandth of an inch on each glue surface.

David, sorry to hear of the hydraulics problem...

Dave

[David Rose]

Hey Dave! Bobby wants a *review* with pics and the works. YOU are the man to do that! I'll give it a try if no one else will, but in my usual fashion I don't know how to keep it from becoming a book.

A lot of things that make the jig fun for me would probably be taken for granted by many users. That "non skid" back plate means that barely any pressure is needed on the holding clamps to do an excellent job. Well, I started the "book", huh?

Dave, I don't consider the hydraulic situation a problem. Everything came out fine with some extra work. I just consider it a learning experience. That is soooome machine!

David


Bobby, the adjustment knob has eight numbers on it. Each number is .002" overall change, a thousandth of an inch on each glue surface.

David, sorry to hear of the hydraulics problem...

Dave

[Charles McKinley]

David,

Thank for the generous offer! I think you should rid yourself of those trouble makers as soon as possible. The UPS truck drive itself here now.

I'm glad it was fixable. After this saga you will have to post pics when it is done.

I would also like to see a full review. Although I said I would not buy a FMT until I masters the dovetail jig.

[David Rose]

Rats! I missed UPS! Oh well, there is always next year.

I should post the little cabinet if I ever get it done.

David


David,

Thank for the generous offer! I think you should rid yourself of those trouble makers as soon as possible. The UPS truck drive itself here now.

I'm glad it was fixable. After this saga you will have to post pics when it is done.

I would also like to see a full review. Although I said I would not buy a FMT until I masters the dovetail jig.