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My three piece back as now become a four piece, as I have been a little zealous in the planing area and gone under the 16" lower bout width...I just seem to have immense problems planing the back plates to the point where that little "chink" of light I see stops shining through.

As a process of elimination, could people suggest what I could possibly be doing wrong, please? I seem to nearly get it, then a little more planing seems to throw it out again.



I have used the cumpiano jig method of the simple shooting board. The wood is flush where it is planed, and I make sure it is flush after checking and re-clamping.

I feel like a total muppet.

Sam Price39038.6664699074

Thanks, Hesh. You've certainly highlighted something there!!!

I have a Record #4 plane...spent a good deal of time honing the blade too...I agree that you can wind up the blade, and the cuts are soo light and crisp it's almost delicious.

I'm reckoning it's the stupid workbench of mine..I'll try my new, flat kitchen worktop.

Thanks Hesh, you've been a great help!!!

Sam a #4 will work, a 5 or 6 is better for jointing. You must also be certain that the sole of what ever plane you use is perfectly flat. It is not common for this to be the case when you first acquire them. It is more normal for the sole to need flattening out on abrasive bonded to thick glass or granite.

Cheers

Kimlarkim39038.6900231481

I also use my Unisaw's table as the bed to run the plane upon . its dead flat, I use a LV low angle smoother, soon to be a LV or LN low angle jack (you hear that Santa ... thats right fatman, I'm talkin to YOU !!!)

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Ok... the purests are going to cringe when I tell you this. But....

If you are very close with a plane, you can put a piece of self adhesive sandpaper on your tablesaw (presuming it is dead flat -- or even better if you have a granite slab) and use the fence as a guide. Simply push in one direction and don't put any noticable downward pressure on it. Make sure you are always sanding on the paper (don't let any wood stop making contact with the paper -- so use a long strip.) Sand both plates at the same time.

Usually less than 5 strokes will close up any gaps.

I don't think a sanded surface is as good as a planed one, but it works and I have never had any trouble with a sanded joint opening up.

Brock Poling39038.6951388889

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Excellent! I really tried hard not to use the sandpaper trick, but thou hast tempted me.



Sam Price39038.6964583333

I ahve done that too Brock, usually on curly or quilted maple .. besides, once you route in the backstrip, plus reinforce the inside with spruce/cedar, there is only about 20-30 thou of the original wood joint left, and its covered by everything else.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Sam i highly suggest that you get a #6 or a #7. A #4 and to a lesser degree #5 are too short to maintain a level plane. Too easy to dig a little deep in an area as the plane first approaches a low spot. the longer the plane the more level the cut. I use a #7 but that puppy is 20" long. a # 6 might be just the right length for this task at 14"-18".

Now with all that said I can give you an inexpensive way to make this seam that is so easy it will surprise you.

Just as you use the plane on the shooting board. buy a precision milled 24" level. You will have to spend in the neighborhood of $40 for one but if you go to a high end building supply store you will find one. Now use 100 grit sticky back paper on the machined levels flange and use the level just as you would a plane. Three or four pass and you will clean up to a nicely candled joint.

Some dont like a sanded joint but with 12 guitars done with this method prior to getting a #7 jointer. none have failed.MichaelP39038.6978356481

Sam I use a Record or Stanley #5 for all my jointing, when I do it, I start with the blade hardly kissing the wood so that in fact only sort of dust comes off. Then gradually adjust the blade ( this will take off the high spots) until you end up with a double curl, full length. Candle the plates, usually it's job done. The secret I believe is to use the minimum pressure possible to get the full length curl.

I just use the tape and tent method to join the plates, always with HHG, and I defy anyone to see the joins. Try it.

By the way, nothing wrong with a four piece back.

ColinColin S39038.7323958333

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

I'm with Colin, #5 Stanley ('cause I've got one). Sharp iron and not too much pressure. If you press too hard you'll not have very good control.

That was my problem, pressing to hard and as I did the stroke I'd be changing the amount of pressure on the heel and toe of the plane as I shifted my weight during the stroke. I think of it like a golf swing, you have to be aware of what your body is doing - but I tend to over-think things.

I also tried Colin's tape method of joining plates. The only problem is finding the glue line if you didn't mark it first.

I just had this same problem. I was using my stanley #5 and could NOT get the back to pass the candeling test. So i broke out my #7 Sweetheart. . Just a few swipes, and it passed the candeling test no prob. Now, that being said, I got a huge deal on the plane. I bought it a #4, #5 a sergent wood block plane. the #7 SW, and a couple of brok e planes for $75. I'm sure I could have eventually gotten it right with a smaller plane, but the jointer was easy. As Robbie says on his DVD, and Cumpiano says in his book. Be patient and don't give up.nathan c39038.8377430556

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nay

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Woodworker++

I agree that a sanded joint is a perfectly viable option. While it isn't, in theory, as strong as a planed joint, in practice, I wouldn't lose any sleep over it. If your glue is good, the joint will be plenty strong -- almost certainly stronger than the wood itself, even if the joint is sanded.

That said, I use my jointer. With sharp knives, it does a great job, and very quickly. I use it for tops, too -- once again, SHARP knives, since it could otherwise make a weak joint due to crushing the softer fibers.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

I'm getting there...patience is definetely needed!!!

Sam Price39039.5451967593

I use a #4-1/2 Lie- Nielsen, and it took me a while to get my technique down. It still takes me a while sometimes to get it right. Just pay attention to your high and low spots and work accordingly.

I recently picked up an old Stanley Bailey #6 on eBay, so hopefully once I get that all tuned up it'll do the job with a few swipes and no fussing.

I used the sandpaper method in Harry Fleishman's class and it worked fine. I prefer planing, if anything because it's just more fun to make shavings than dust.

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Jonathan Kendall, Siloam Springs AR

lest i sound like a casper milquetoast, let me preface these comments by saying i'm 6'1", look emaciated at 220#(don't i wish i could get anywhere near that now), put shoes on horses for over 40 years, played american football through university level, and played rugby for 35 yrs, finally being forced to give the game away when i was 52.

and over the years i've tried a variety of planes from a block to a no 7 jointer for jointing plates, and managed to get good results from just about everything but the block. and whilst they can do the job well enough i find a fore plane or a jointer way too heavy and cumbersome for the task. whilst i've achieved more good results with both a no 4 and a no 5, i prefer the no 5. i gives what is to me a good level of convenience and ease of use whilst producing very good results quickly.

for stock the length of what we work, using a plane almostas long as, or as long as the stock seems gross overkill. the long planes are just too much tool to my way of thinking.

A couple of details should be mentioned regarding any sanded joint. First, glue the parts together soon after preparing the joint, as the fresher (less oxidized) surfaces make for a stronger joint. Second, make sure the gluing surfaces are dust-free. Vacuuming or even blasting with compressed air are good ways to do this.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Todd, how do you feel about wiping the jointed (sanded) area with a damp rag?

SKSteve Kinnaird39039.9615740741

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com

Sam, do you have a router?

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Aoibeann

a jointer edger is a very nice tool to have but makes a lot of noise though.

+1 on the sandpaper so long as it's a flat sutface. Remember you can get a roll of sandpaper for electric sanders so there's no problem getting a 30" long strip....

And 4 piece backs aren't a problem......

MOST of mine are 4 piece, and the doubleneck I'm plodding along with is a 5

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Martin; I'm hitting the DIY stores tomorrow...

Have you got a biscuit jointer at work, or do you use the plane or sandpaper technique? I've seen your seams, and uh....I can't see 'em for such precise jointing skills...

Aoibeann: Yes, I have router. T'was a gift from a friend, given to me a couple of months ago. Sam Price39040.4266666667

You can make a jig and edge them with the router. Its really no more than two pieces of MDF or plywood that are larger one piece of your sound board. Recess the bolt heads so they aren't in the way. The wingnuts end up on the bottom, because they are in the way. Use a spacer and clamp it to your workbench. You sandwich the soundboard in between the two with just a bit of the joint edge showing. Use a straight pattern bit to follow the straight edge of the jig. I hope this made sense.

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Aoibeann

[QUOTE=Steve Kinnaird] Todd, how do you feel about wiping the jointed (sanded) area with a damp rag?

SK[/QUOTE]

Steve, I don't know. My guess is it's probably fine to do that. My first thought is wondering if raising and swelling the grain prior to applying glue and clamping would have any significant effect on the quality of the joint. My guess is that it wouldn't. In any case, the wood is wetted by the glue itself in the process of gluing it together (forgive me for stating the obvious).

I do suspect, though, that wiping with a damp rag doesn't remove the dust as thoroughly as vacuuming or blowing it off with compressed air. Probably not enough of a difference to really affect the quality of the joint, though.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/