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Hi everyone, this is my first post. I am sure this will be the first of many as I am just setting up my basement shop and just starting on my first build. I have built a few pieces of furniture in a semester long woodworking class in college (about 8 years ago), so I'm not a true beginner at woodworking.

I am trying to get a straight edge for gluing up the back book matched pieces right now. I got an old Powermatic model 50 6 inch jointer off of craigslist and tried a few passes on it without set up, and every time the edges got progressively more convex. I'm sure i need to work on my technique, but the blades are dull and need to be replaced, and the jointer needs to be set up (may not be co-planer). I discovered a method to true up the edges simply using a router with a straight bit and a straight edge. I think this method may be better than using a jointer. I made one pass with the router, 'opened up the book', and it came out far better than what the jointer would produce, but i still see a very slight amount of light through the two halves, and i can get a .0025 feeler gauge through. Is this a close enough tolerance? I am scratching my head on how i can get any more accurate than a straight edge and a router. Maybe I need a new router bit? Any other suggestions or help on edge joint truing up and gluing would be great. thanks!

I think 2 1/2 thou is a good bit too big for a good join. I haven't done any
specific testing, but I think I go for .001" or less. If you do a search on
jointing plates, you'll find many ways to do it. One of the simplest and best
is to us a hand plane. I've used almost every size of plane at one time or
another, but a mid-sized plane like a #5 is probably the easiest. Here's one
good thread on the subject:

http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=29563&hilit=jointing

You can also use sanding, but you need a 20" or so long very flat surface to bond
the sandpaper to- like a glass plate.

You'll definitely need to do a major tune-up on the jointer before trying to use
it for this use.

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Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain

Check out Todd Stock's shooting board instructions in the Tutorials section. Easy way to get a great joint. viewtopic.php?f=10117&t=22540

I'd say that if you can see light then the joint is not good enough.

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http://www.PeakeGuitars.com

thanks for the help guys. i will look into making a shooting board. any recommendations on planes?

Gil: If the halfs are touching on the ends and no where else then you will have what is called a sprung joint. It will easly close up if you are using enough pressure. I have done these before and used the old roping method with wedges for gluing pressure. The thought behind using this type of joint is that wood loses moisture most easily on the end grain. If there is moisture lost at the end there is not as much stress in the glue joint at this point.More important to me is that you have a clean fresh joint for gluing. My self I would go for a sharp hand plane with a fine cut. Good luck.
Tom

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A person who has never made a mistake has never made anything!!!

hi tom - when using the jointer it is actually the opposite. the gap is at the ends and it gets worse with each pass through the jointer. when i used the router technique it shows about a .0025 gap at various spots throughout the edge joint. i have a stanley 12-060 6 1/4" block plane. i reckon this is too short to make a good edge joint. any suggestions on planes would be great.

on a completely unrelated topic, would anyone care to make suggestions on how to properly store tonewood? I have been stocking up on tonewood at various thicknesses but roughly near final shape and thicknesses with the sides cut as well. i have a basement shop that is partially above ground and stays dry (humidified in summer). Should i sticker it?

No reason for spring in a joint that is: A. only 24" or so long and B. is for a guitar. The ends are captured anyway so there is not exposed endgrain to lose moisture.
On a guitar top it would be even worse as the sound hole is where the most spring would be. Most woodworking situations it is easy to over do the sprung joint thing.
You need the joint to be perfect, wood to wood contact the whole way. If one were to er a bit it would be better to have it open or sprung in the middle of the joint on the back but not for the top because of the reasons I stated about the sound hole. Any amount of "spring" should be able to closed with fairly light finger pressure.
Seems daunting at first but doing joints like this becomes second nature with a little practice. FWIW I am totally of the hand plane persuasion.
L.

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Cut to size.....Beat to fit.....Paint to match.

Veritas 5 1/4 is perfect for me right out of the box.

If you use your head and have a sharp block plane, you can joint a top/back with it.
Bogdanovich uses a block plane for jointing in his book, as I recall.

A decent aluminum level with sandpaper stuck on, and an improvised shooting board also work pretty well.

Use scrap or a cheap top for practice- it can get narrow in a hurry.

Light-tight is the minimum standard for me - I like to feel good friction between the 2 pieces all along the joint.

Keep at it, and don't accept 'good enough' too quickly on this......

John

Certainly technique can affect joint accuracy on a jointer, though it is most likely a setup issue on the machine itself, they can be finicky, but once you get them dialed in a quality joint is simple. Then again, doing it by hand works great too!

Greg

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Gwaltney Guitars

You can spend a lot of money on planes, or not. I've made due with a Stanley plane (don't know the number, but it's 10 inches long). My own opinion is that the blade is more important than the plane (yeah, I'd like a Lie-Neilsen, but the $$ are going to hockey equipment)....

A good Hock blade, in that Stanley, and spending some time learning how to sharpen it properly, so it's REALLY sharp, works great. (Won't go into that here - lots of good threads and tutorials here on sharpening methods. If you're not into spending lots of $$, the scary sharp approach with a plate of glass and different gradations of sandpaper works fine.) I've found I prefer waterstones, and sharpening freehand, without a sharpening jig. Anyway, lots of ways to skin the cat.

Don't have a Hock or similar blade? No problem, but you'll be sharpening more often - the standard blades that come with Stanley and other planes aren't very hard.

If the blade is super sharp, you can adjust the plane to take a shaving off that's so thin that it's much thinner than paper.... just keep backing it off, so that you're almost not taking a shaving at all. For me, that's the key, if you're taking a "curl" for me it's not fine enough. Spruce will "ripple" rather than curl, when I get close to fine enough. Again, truly sharp blade or you're going to be very frustruated. How do I know this??

I find I can "spot plane" the high parts once I'm close, to eliminate any light at all. In other words, it finally occurred to me that nothing says you have to plane the entire length, hoping that it ends up straight. Get it close, planing the length, then check for light, and gently hit the high spots, using the shooting board. Works great

Have fun.

With all due respect to those using a shooting board, it can be lived without it. I simply use a neck blank on which I put the two halves and press them down with one hand while pushing the plane with the other. Maybe with a board it would be a bit easier or faster but I don't feel the need yet. A good long plane (Jack or longer) plane, well set up and very sharp is the really important part and it should make "zero light" easily achievable. At the finest setting you are not looking to get a solid shaving but something extremely thin, fluffy and rippled, that crumbles to dust when touched.

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Build log

So the master asked me how the plate jointing was going.

"It'll do" me replied.

"Sorry, no. keep working it" .


A while later he asked again how the joint was. To which me replied"Good enough."
"No. thats not good enough. " he replied "Keep working it."

Frustrated, me went at it some more and finally went up and said "Sir, it's perfect"

He looked me in the eye and said, "Well son, thats good enough then, it will have to do"

Ya, the old guys taught in funny ways they did.



blessing
Padma

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Audiences and dispensations on Thursdays ~ by appointment only.


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for me light tight is the only way. no gaps, no feeler gages.

first i use an ancient craftsman smoothing plane that's got about an 8in long sole. i don't really have a "shooting board" but i just have some dedicated hardwood pieces that i use for registry and clamping onto my work board. i like to clean up the side opposite the joint also to get a clean area to locate from.

after some passes with the plane then i'll do a quick rub together and then do a light check. the rubbing burnishes the high spots which are easier to see. if all is good then on to the glue up board. if they need a touch up then i'll take a scraper to the edges and recheck. this actually goes by fast -about 30 min.

however one does it the key is light tight and as perpendicular as you can. good tops and backs start with the best possible joints.

thanks for the great responses guys. wow, those lie-nielsen planes sure are nice. i may have to work up the funds and get a 5 1/2". i never thought i would think of woodworking tools as eye candy until i spent an hour on the lie nielsen website! hey todd, what thickness and material plywood are you using for your shooting board?

Stanley 5.5 for me, 1970's vintage. fettled a little. Blade is an old Sheffield Acorn - as thin as the standard blade. Does it as good as any plane out there. So much so that a chap by the name of David Charlesworth went and copied me.
I'm not sore about it though.

I use a jointer plane and shooting board to get a sprung joint, and then I use a straight edge with sandpaper, and a shooting board to get the final surface. This has two advantages, the edge is perfect, and it is slightly rough for glue.

Shooting boards can be set up to cut a perfect joint without the sand paper, but it is easier to use the sanding board, and does not require a very accurate shooting board since the surface of the board is not being copied in this process.

I saw a vertical jig that does much the same thing, for sale. But I prefer a simple horizontal board.

Me has had 4", 6", 8", 12", and 24" jointers...in me life, or should me say "they had me."

Got rid of them all. But then me must admit there was this 6" delta that looked me straight in the eyeball and said 'pppplease take me home with you", So me did...use if for break out only.

Now me just use a # 8 Stanley, upside down, in the vise, no fence and shoot the plates by hand. Simple eh.

Oh and for those of you that uses sand paper for joining, tell me, what granular size of sand do you use in mixing up the mortar to mechanically cement the plates together with? And I'm old school... Just wondering.


Blessings
Padma

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Audiences and dispensations on Thursdays ~ by appointment only.


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I did my first couple plates entirely with a hand plane, which I later discovered was horribly concave... it took all day carefully planing the high spots and figuring out the exact pressure variation along the length of the boards to get it to cut straight. I found a longer, flatter plane down in the basement, but I still can't get it to cut a straight joint without a long process of selective planing. Just gets more and more convex if I shoot the whole thing repeatedly. Maybe this plane is a tad concave too, or maybe I'm not getting the pressure consistent at the ends, or maybe I take too big of shavings (probably due to lack of sharpening skill). Oh well, hopeless to plane curly hardwoods anyway (or is it?).

So what I've been doing now is hold coarse sandpaper against the plane and go back and forth, checking and being somewhat selective of how far back and forth I go, until it's nice and flat, maybe with specks of light visible due to the roughness. Then smooth it out with 100 grit until light-tight, and finally take a couple super fine shavings with the plane to shave off the roughened surface without taking enough to start developing gaps at the ends. Way faster, and gets the same quality joint in the end.

My jointer has the same problem. It's a small one, the bed is not long enough to get a perfectly straight edge easily. I run the plates through the jointer first, they always come out slightly convex. I then use the stew-mac adhesive backed sandpaper on my table saw to perfectly flatten the edges. I clamp down a 24" box beam on top of the strip of sandpaper to keep the plates at a 90 degree angle to the sandpaper and gently sand the edges of both plates at the same time. If you lift the plates off the sandpaper after sanding a bit, you can see on the sandpaper when the middle of the plates are close to contacting the paper, at that point I hold them up to the light. I do it until I get no light at all. Works great and very quick.

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Damon Wack
https://www.facebook.com/LindamonGuitars

speaking of planes, every one i own i have had to rework. i usually take them to work and surface grind the sole to get them back to square. the .010 to .015 out of squareness of the average plane is a joke. the flatness is none too good either.

has anyone tried the Lie Nielsen No. 51 Shoot Board Plane? http://www.lie-nielsen.com/catalog.php?sku=1-51 Is this overkill?

Any one of my $10.00 junk store Stanleys from any era will do the job and do it well. I don't understand the need for these high dollar planes.

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Hutch

Get the heck off the couch and go build a guitar!!!!

That looks pretty cool, but you'll find more use and versatility in a 5 or 5 1/2, plus a less expensive entry fee. When I was going through my initial tooling up, I thought my planes would be single-purpose tools. The 5 1/2 is more or less used for jointing and truing up the fretboard edges, but my block plane is used ALL THE TIME. I can live without my finger planes, but I'd be lost without my Lie-Nielsen 5 1/2, 60 1/2, and Model Maker's planes. These are, without a doubt, indispensable to me.