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Is there any good reason NOT to just joint my top and back plates using a sled on the table saw?

I typically do this for other woodworking plate joining (not musical instruments) and get good results. Is it going to be better with a shooting board?

If you can get acceptable results that way then go for it. The gluing surface needs to be very smooth and perfectly flat. You should also be able to hold the joint up against a light and see absolutely no light coming through. This is definitely a part of the guitar building where anything less than perfection will really get you in trouble. Most folks use planes to accomplish this and it's what I recommend learning how to do for this key and crucial part of the build process. But again, it doesn't really matter how you get there, so long as you get a proper joint.

I think it all depends on your expectations regadring the joint. I am very sure that mine are not reached with any kind of machinery.....

Glue one up and see if you can get it to break apart at the glue line or if the wood fails first. My guess it is will work fine with softwoods since the surface compresses enough under clamping pressure to squeeze out minor imperfections, but hard back woods will need planed.

The best joint is always going to be with a shooting board (or other system to get a steady angle) and a well tuned plane with a freshly sharpened blade, plus a lot of practice - sorry!
You can possibly get an adequate joint using a sanding shooter, or a jointer, for example.
Never heard of anyone using a table saw, or even a panel/cabinet saw.
With a really good table saw I can see jointing "plates" working for thicker material.
A builder I know had a top end swiss made(?) cabinet saw which cost some rediculous sum of money and cut a beautiful surface you could joint off the saw - for thicker sections of wood.
You wouldn't have a problem using the finish left on the top surface of a neck for gluing a fretboard for example.
But for jointing plates at around 0.15" initially, even as a machinery "freak", he used a jointer.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I think the guitar factories use jointers. If you can cut the edges on the table saw and get surfaces comparable to what comes off a good jointer, maybe it will work. Myself, I use the table saw, or a router table set up as a jointer, to get the edges in the ballpark of straight and square, then get them where I really want them on a shooting board. And I do shoot with a sandpaper-covered long straightedge. It gives me the flattest, most square, edges I can personally accomplish. No seam failures so far. In fact, the seams disappear on me, and I have trouble finding them without notches at the ends of the seams telling me where they are.

With a well tuned high quality table saw and the right blade freshly sharpened you can make an acceptable joint. The average home shop saw would make it hard to do. I use a jointer and get decent results. If when you lay the two pieces together the joint "disappears" it would be O.K.
You want the finished joint to not show any glue line. Using hot hide glue can help. As it dries it tends to pull the joint together, and makes less conspicuous joints. It is good practice to have a perfectly joined soundboard from top to bottom, but the critical part is from just below the sound hole to the bottom of the guitar. Obviously the sound hole area doesn't matter, and in most cases the fingerboard covers the upper bout area of the joint, so a slightly imperfect joint in these areas is acceptable. Relieving these areas a "whisper of a plane shaving" can help you perfect the critical part of the joint.
Using a decorative back strip can help obscure a slightly less than perfect joint in the back plate. The back graft on the inside will reinforce a weak joint.
Most of the sleds I've used have too much "play" in them to do a long joint perfectly. A good table saw fence might give a better result. But you know your tools and what you are capable of better than we do. A well planed joint can make a stronger joint than a well sawn one, but a well sawn joint will be stronger than a poorly planed one.

+1, with the additional detail of cleaning the glue surface with compressed air.


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I had my jointer beds and fence ground perfectly flat on a large surface grinder and have been using it for tops, backs, sides, neck, etc. for over 50 years and never had a joint failure (that I know of).

You prefer the jointer or table saw?

I always get some snipe on my jointer.

All - thanks so much for the helpful advice here. I am going to try table saw and see how good of results I can get. I am confident I can get no light to show through. I have a very good table saw setup.

Can't imagine doing this on the table saw. I don't get any snipe since having the tables surface ground (it puts them on exactly the same plane) of course one has to be very conscientious about setup when you change knives.

j

"I don't get any snipe since having the tables surface ground (it puts them on exactly the same plane)"

Did you have to haul your entire jointer down to the shop to get it surface ground, or did you take off the tables and have to re-paralle them?

Ed

Snipe on a jointer can also be caused by having your outfeed table set too high or too low in relation to the knives in the cutter head.
Unless your tables are warped you can usually shim the tables to get them parallel.

https://www.youtube.com/watch?v=jAyktFxZfwQ
https://www.youtube.com/watch?v=PNOt1SvjoLs

I hauled it to the machine shop (no stand or motor). You have to find a machine shop that has a large enough surface grinder to do the job. In my case it cost me around $120 but keep in mind that was 50 years ago so $120 was a lot more money than now. Clay's solution would probably work fine but I'm too lazy for that. I did this at the behest of a wonderful friend who was a genius woodworker and mechanical wizard.

I have a sled for my table saw (a SawStop—it’s a good saw) made just for the purpose of truing up plate edges. I use it to clean up the edges before I joint them with a handplane on a shooting board. I use hot hide glue for the joint and expect a perfect edge before I glue. The table saw does not give a perfect edge. It just prepares the edge for the real jointing.

I’ve experimented with two other methods of jointing—a flush cut router bit and a steel certified straight edge, and the flat sanding bar. The steel certified straight edge was guaranteed to .001”. That guiding the router wasn’t good enough for a perfect gap-free joint. The flat sanding bar enabled me to use a back set that just wasn’t going to be planed (grabby grain), but it wasn’t as good a joint as I wanted and I ended up inlaying a center strip over it. For me, nothing has worked better than a good sharp plane and a shooting board. And, whenever that setup gives me trouble, I know to resharpen the plane. When it works, it gives good results quickly. When it doesn’t work, I resharpen the plane.

With modern glues, you can get away with most anything. A radial cut from a tablesaw or a continuously cupped cut from a jointer will work. However, if you plan to do this for awhile, learn to use a plane. A nice modern plane will set you back nearly as much as a cheap tablesaw, but you can buy extraordinary old Bailey planes on eBay for a quarter of the price. Add a Hock blade and your are in business. I have both modern and vintage planes and they are a joy to use. Not that hard to develop what little skill it takes to use them either. They are such nice, quiet tools and a hand plane sheered edge is awesome IMO.--Bob

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“ The meaning of life is to find your gift and the purpose of life is to give it away” Pablo Picasso

Sorry, I thought you were asking if it would be a better joint with a shooting board, not if it might be adequate using your table saw.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

A man's got to know his limitations and deal with the situation accordingly. I think he knows most of us feel a well planed joint is a better gluing surface, but like the people who use a sanded joint has decided to settle for a sawn joint. We picks our poison and takes our chances. I use a jointer because it is easier than setting up for a hand planed joint and it satisfies my idea of "good enough". I know a hand plane can make a slightly better surface but the jointer is quicker and takes less skill. It is a means to an end.

I'm a mostly hand-tool guy with a collection of vintage tools that I love to use. I am not afraid of machines for the truly hard work - ripping long lengths by hand can be more tiring than I am interested in. I have a friend who even does that by hand though. And I know people who rely on machines but own a block plane because they thought they needed one.

There are many ways to successfully get a job done and I see no reason why a table saw, with maybe a block plane touch-up, wouldn't work.

That's why they make chocolate and vanilla

Ed

Myself as an example: I’m not totally useless with handplanes. I use them lots during a guitar build. I have a decent shooting board, competent sharpening skills, a nice jack plane, etc. but when I shoot a center seam with a plane, I just feel like I am constantly chasing a little problem in this spot, then down here, no, wait, now there’s a gap up here again . . . In contrast, the same exact setup with a long straightedge, faced with PSA sandpaper, yields a perfect edge in a minute. Boom. I trust sanding to get me a decent gluing surface in just about every other place on the guitar. I understand that a planed surface is technically better than a sanded surface, but in my view, a perfectly fitting sanded surface is better than a gappy planed surface, and it takes me way too much effort to get a perfectly fitting planed surface. Both planed and sanded surfaces exceed the requirements for avoiding joint failure, when fitted well. So, I sand it and feel good about that choice.

The last 3 posts seem to be in "response" to my last post, rather than to OP.
Hey, guys, anyone can do whatever thay want to. Sanding, routing, circjular saw, whatever they want.
I just reread the OP to check, where it said, and I quoted "Is it going to be better with a shooting board"
The simple answer is, in IMHO, yes.
He didn't ask is it going to be easier, or is it going to hold when glued when done like this.
Some people have perhaps not developed the skills or confidence needed to do this with a plane, and use other methods which produce acceptable results, and that's fine.
I have had students who jointed their own plates surprisingly fast - no real experience of woodwork, just by being talked though the process.
I recall a post on OLF where a teacher told of a class of young school pupols doing a class project all jointing uke(?) plates using block planes.
Much of the "skill" lies in fettling the plane, sharpening the blade, and setting the plane up. Plus probably a lot of persistance.
Just my $0.02

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I wouldn't joint top plates using a table saw. Everything has been tried before and accepted practices earn their status for reasons.

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George :-)

Opinion? No. EDIT! Sorry, YES, it’ll be better with a shooting board. I read it as “better THAN as shooting board” in my non-coffee brain.

Experience:
Table saw vs. Jointer? Jointer.

Jointer vs.1903 antique Stanley #6 (or #7, bought off eBay for less than the cost of a modern blade) with a modified throat to fit a thicker Veritas blade, flattened and squared side, on a Rob Colman shooting board? Hand plane all day long.

Mind you, it took me years to finally go to a plane. Why do old school, manual plane, when we have modern tools to do the work? If you know, you know. And seems there’s more than few here that know.

If you get acceptable results from a table saw then go for it.


Personally, I have 4 table saws, and only 1 would I consider capable of producing a face suitable for jointing. This is a $10k saw, This unit still pales in comparison to a jointer. This is a jointers purpose, to create a flat surface. If the jointer is not doing this then the set up or technique needs attention.



If you are referring to jointers, they have been in existence for 150 plus+ years, predating metallic hand planes.

There are multiple methods to achieve a good joint and you need to consider practicality and what is an acceptable joint. For many this would be a plane and/or chute board, economical, compact and effective.

Tool nerd.

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My memory is so good, sometimes I remember things that never happened.