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miche
07-13-2016, 02:50 AM
Ok so I am not great at jointing plates. I always seem to be chasing the gap. This time around I was determined to joint the plates just with a handplane and not resort to sand paper but after two days jointing this sycamore back I gave up and resorted to sand paper. Anyway this is a part of the joint I ended up with after it was glued and sanded flat. It is so visible. I have seen invisible joints but am yet to achieve one. I am thinking of cutting it in half and starting again. Do you find it easy achieving invisible joints with hand tools?

Mimbler
07-13-2016, 03:26 AM
Has the joint been face sanded after gluing to remove glue residue and flush out the surfaces? Until that is done, I find it hard to judge the quality of a joint. If that has been done, I would be tempted to cut and redo, if I had enough excess to do so. You'll both get a little more practice, and probably a little better joint without a huge investment in time,
Mike


Ok so I am not great at jointing plates. I always seem to be chasing the gap. This time around I was determined to joint the plates just with a handplane and not resort to sand paper but after two days jointing this sycamore back I gave up and resorted to sand paper. Anyway this is a part of the joint I ended up with after it was glued and sanded flat. It is so visible. I have seen invisible joints but am yet to achieve one. I am thinking of cutting it in half and starting again. Do you find it easy achieving invisible joints with hand tools?

greenscoe
07-13-2016, 05:48 AM
It's a topic that's been discussed many times on this forum (try searching). There are many who do this with power tools (planer, table router.... etc). There are many who like you are still trying to find a way to do it using hand tools. But there are also many who do this routinely and successfully with hand tools. Some will use a shooting board but this isn't absolutely essential as long as the wood is supported and the plane remains perpendicular to the wood.

I have a long plane which isn't used for much other than joining boards. I find its essential to keep the blade very sharp and very finely set so little material is removed with each pass. Its a bit like learning to ride a bike: it seems so difficult at first and after some practice you wonder why you had a problem.

I can only suggest you set up a good plane and start practising on scrap material so that next time you do it for real you'll find it easier.

ksquine
07-13-2016, 07:03 AM
I don't think that joint will never by invisible because the grain forms a V (from the photo anyway). You'll always see the V and a sight color change from side to side with different lighting.
I would sand it smooth and wipe on some mineral spirits to see how it will look finished. It might just need a clean up to look good

Allen
07-13-2016, 10:22 AM
Unlikely to ever be an invisible joint in that light color timber and some slight end grain at the joint from that converging grain pattern.

If you "candle" the joint to make sure it's tight (I hold mine up on a window so it's held flat as if it was glued) and you don't see any light coming through gaps, then that's as tight as you are going to get the joint.

mainger
07-13-2016, 01:55 PM
It's quite difficult to see on the photo as the image size is quite small. Is there a visible gap between the each plate? If so, then perhaps cut and redo it as suggested already.

I use an old Stanley No7 for this job, and only this job, and it's the one I sharpen most carefully. Not had problems with joining plates in a long time. And I think it's quite doable with smaller planes than that.

sequoia
07-13-2016, 07:51 PM
Yes a subject much discussed. I used to sweat this one and could spend hours getting the perfect invisible join. Then a light or something went off and I realized that this operation is as easy as shooting ducks on a pond. Here is how to do it and no power tools, fancy shooting boards or other crap or fancy things needed: Take your plates and tape them together. The key is to tape your plates together with the show sides (the part you will see on top) taped together on the inside. The whole key. Then sand your edges on a flat surface. This will result in a a slight concavity where the ends of your plates will show light on the ends but not in the middle. Don't despair! NOW, take your plates (with show sides inside), crank them into a vice and take a 2 or 3 foot level (any cheap framing level works) with sandpaper (100 grit) taped to it and finish sand the plates. A couple of minutes or even seconds will even out the concavity and put a perfectly flat surface. Remove from the vice. Your "down" side (the outside) will show a seam (who cares), but your inside (show side) will completely disappear. One problem with this, and I'm serious, is that your center line will completely disappear and can be hard to find. Seriously. It takes a good eye to find where your center line is and you gotta find your center line. Time: 10 minutes max. Good luck! Easy peasy.

pointpergame
07-14-2016, 04:01 PM
A joint like this is a trivial hand operation. On a harpsichord with a (roughly speaking ) 3 foot wide by 4 foot long soundboard, it takes 5 or such joints in very thin spruce. If it were difficult, most harpsichord builders would go crazy with frustration. I'm saying, step one is to realize that there's an easy way to do this.

Like several posters here, I find the #7 ( Actually, I have a lovable #8 bedrock) jointer plane works well. There's almost no wood removal, so any suitable shooting plane would work from a block plane, a #4 or #5, a dedicated shooting plane, or just a nice jointer. So long as bottom and one side are square to each other and the blade is sharp, it'll work.

Here are my "secrets."
1) You have to use a shooting board. This isn't a fancy item. You can simply stack one flat board atop another. 3/4" inch stuff is good. No twist but the beauty of a shooting board is that dimensions and end to end bow are not critical. If you're going to use it again, you can screw the top board to the bottom one. You can find a lot of examples on the internet, just figure it out for yourself and realize that many of these examples lack insight into what's critical and what's not about a shooting board.

2) Shoot the joint a "little bit" hollow. On a joint 4' long I go for about 1/32" for a shorter joint, maybe 1/64" to 1/100". The beauty of this way of working wood is that you have this kind of control.

3) Here's the big secret...though it's dead obvious once you think about it. Make sure the faces of the two soundboard halves are finished perfectly front and back before you start. Make sure your shooting board environment is extremely clean because if there's even a thick piece of sawdust on the shooting board it will make a dent. Shoot the left half ( say ) of the soundboard with the face up. Shoot the right half with the face down. This EXACTLY takes out the angle difference in the two halves, absolutely guaranteeing that the two halves will sit in the same plane...that is, the joint will add to exactly 90 degrees. You only need two or three passes with the plane. But more passes won't hurt anything.

This joint will be invisible even before you glue it.

Finally, lay the two halves together with a batten under the joint. Like a wooden yardstick. Secure the outer edges with battens or just a line of nails. When you slip out the yardstick the two halves will fall together with almost exactly the right amount of perfectly even pressure. Put a heavy weigh on each half. If you put the right amount of glue on the joint and rub it first, there should be only a tiny bit of blue bead so you won't have to mess up your faces with a lot of dried glue removal. Just scrape it off gently at this stage with a fresh, sharp scraper. I've always thought that water at this stage could ruin the joint, so I've disciplined myself to put on the right amount of glue. An idea, BTW, that I got from one of James Krenov's books. You can practice this with scraps or you can practice it with the real soundboard. If it doesn't work out, rip the two halves apart at the joint and do it again.

Good luck. PM me if you have questions.

Rrgramps
07-16-2016, 04:13 AM
Excellent advice on making a simple shooting board by stacking two boards together and offsetting the top board by a plane width for a runway.

Not necessary and probably no more effective or practical for a skilled luthier, is a shooting board and handmade plane like this one:
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