Cutting Long Veneer Joints

[alex grams]

What is the best way for a long veneer cut? (40"-50") I have a few pieces of burl (50"x15") I am going to joint up for a desktop, but they are too long for my standard 'sandwich the veneer between two boards and run it across the jointer' method.

What would be the best way to get the perfectly flush straight cut I need?

Trimming along a straightedge with an exacto/razor blade tends to walk a little. The veneers are about 15" deep, so clamping them in the middle would require a clamp with a throat deeper than anything I currently own. I could try a veneer saw, but those have mixed reviews. Though I may buy and sharpen one to give it a try.

The other option for clamping would be to make about a 50" caul that would provide even pressure along the length of the boards when I clamped at both ends. Then I could hand plane it. The challenge being that the cauls are wider than the plane blade, and any caul narrower than the plane blade will have a hard time acting as a caul. Then again, I could use the caul to hold two pieces of 3/4" wood against each side of the sandwich.

Another option is maybe a straight edge with a router and a trim bit? Climb cut it with a 2 fluted flush trim bit maybe?

I am really not familiar with how burl will behave with to each of these methods. I do have to trim about 2-3" off of the edge of the veneer to get to where I want to make the joint, so I can do several test cuts prior to doing my final actual cut.

Thanks in advance.

[Jamie Buxton]

To edgejoint veneers, I use a handplane. I sandwich the veneers between two pieces of plywood, with the veneer hanging out just a bit -- maybe an eighth. I put the sandwich down on the bench and pile weights along it. I have some old lead window sash weights, but anything will do. Enough weight will hold the veneer flat, and will prevent the sandwich from scooting around when you plane. You're only cutting the veneer, not the plywood, so there isn't a great deal of force involved. This technique works with any size of veneer -- long or wide.

[Chris Padilla]

Same thing as Jamie does...you can use the same concept you have used on your power jointer and simply do it by hand.

You can use a nice sharp plane or a block of wood with sandpaper glued to it works just fine, too.

Router and trim bit works, too.

Bowclamp makes very nice cauls or just look at their concept to make your own.

Skip the veneer saw...never had much luck with those.

[Matt Day]

Since you're going to use hand tools, you don't need super deep clamps to go around the veneer. I put two boards to sandwich the veneer like the others have said, but I clamp the ends down with 2 regular F-clamps on the ends, and use regular F-clamps on the front and move them out of my way as I work the piece down the length. I usually use a sanding block, but I'm sure a hand plane would work just as well.

[Gerry Grzadzinski]

I overlap the two pieces, and route both at the same time with a 1/8" downcut spiral. My fence locks in position over 1 piece, and I weight and tape the other one down. I find that if I try to trim less than 3/16", you may get tearout. But if you trim more than the bit diameter, it usually works fine.

[alex grams]

Gerry, do you have a piece of wood under the overlap that the bit also cuts into, or do you just have a lip of veneer sticking out free that you route through?

An interesting method. Baring any tear-out or movement of the veneers you are guaranteed to get a flush joint, even if it isn't perfectly straight.

[Mike Henderson]

For a burl (which chips easily) I put gummed tape along the edge first. Then I use a couple of boards that have been jointed straight (or plywood or MDF) and put the veneer between the boards with just a small amount sticking out. Then I sand the edge with 150 sandpaper glued to an MDF block.

Usually when you're doing that, you want to match the burl in a bookmatch (which means you're sanding more than one piece of burl in the sandwich). I take the veneer out and do a trial fit. If it's close, I can sand the high spots without putting it back in the sandwich. If you're off by a bunch, mark the high spots on the gummed tape and put it back in the sandwich and concentrate on the high spots.

A problem is that the sandwich flattens the veneer but when you take it out, it goes back to it's normal shape which can affect how straight the edge is when you go to put the pieces together.

Patience is your friend.

Mike

P.S. If you're doing a bookmatch, make SURE you have accurately aligned the veneers in the packet before you cut and sand the edge. If the alignment is off, you'll go crazy trying to get the bookmatch to really match.

P.P.S. I see you need to trim the veneers first. I'd put gummed tape along the line you want to cut before cutting it with a veneer saw, but a good sharp knife and straight edge should work also. But tape it first and you won't get as much chip out.

[Jim Tobias]

Alex,
I always do the "clamp it between 2 long pieces of MDF and then put bricks(or whatever is heavy) on the middle areas. I find that I get a better result (just my experience) using long sanding blocks. You just use some sticky back sandpaper and make the equivalent of a jointer plane. I start out wiht 150 grit to get it straight and then maybe go to 220 or so to get a smooth edge and a tight fit.

Jim

[Gerry Grzadzinski]

Yes, the "jig" is a piece of 1/2" MDF, with a 1/2" Baltic Birch fence. the fence is screwed to the base on one side, so I can lift it and slide the veneer underneath. I put a clamp on the other end when I route. I use the groove in the base to line up my seams.

[alex grams]

Mike,
Any particular reason you use gummed tape? I've been using blue painters tape for my veneer glue joints and have been MUCH happier than the standard veneer tape.

I have done the tape for single cuts so prevent chipout, but with cutting two pieces at a time for a bookmatch, do you put tape on both pieces?

I am fortunate that the veneer is VERY flat for being a burl. It sits flat with no more than 1/8" variance.

[Mike Henderson]

Mike,
Any particular reason you use gummed tape? I've been using blue painters tape for my veneer glue joints and have been MUCH happier than the standard veneer tape.

I have done the tape for single cuts so prevent chipout, but with cutting two pieces at a time for a bookmatch, do you put tape on both pieces?

I am fortunate that the veneer is VERY flat for being a burl. It sits flat with no more than 1/8" variance.
When sanding the edge, I find the gummed tape sands a bit better than the blue tape. But it's not a lot. I sometime use blue tape. When cutting through a packet of fragile veneer it helps to put a piece of tape on each piece where you'll make the cut.

Just a comment for others, if you use blue tape make SURE it adheres all along the veneer. It's easy to have a section where the tape is not attached well and you'll get chip out there. Use a small roller and roll the blue tape down.

When gluing seams, one advantage of the gummed tape is that it shrinks a bit when it drys. That's good and bad. If your joint is not perfect, the shrinking can pull it tight. If your joint is perfect, sometimes the gummed tape can pull the joint too tight. So it's a case of choose your poison.

Mike

[And just a comment on aligning a packet of veneer (you may know this). The packet has to be aligned along the figure, not the existing edges.]
[I have to agree with you about some of the disadvantages of gummed tape. I've started using blue tape in some of my jobs but I'm not ready to declare it a better way yet.]

[alex grams]

Thanks for the info Mike. I've got to say I really like your bubinga serving trays with the compass rose. That and the front porch swing are two nice pieces.

This is my first large veneer project, so I am learning as much as I am doing :)

[Chris Padilla]

You might find the building of my Tansu (http://www.sawmillcreek.org/showthread.php?t=92396) interesting, Alex.