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Here is the latest Luthier Tips du Jour video. - In this video I talk about how to join top and back plates using a sanding bar. This video as well as all my other videos are available via my website, http://www.obrienguitars.com/videos , LMI's website or on Youtube.
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Considering the price of the sanding bar compared to the price of a used #4 smoothing plane and a homemade shooting board, and the results you can achieve with them, I'm not sure you are ahead of the game with the Lmi tool where cost is a primary consideration.
I have used a 2 foot cast aluminium level with sandpaper stuck to the edge to touch up some joints.
For those starting out in this hobby I think it is worth pointing out that for the soundboard seam it is only necessary to have a perfect joint from the lower edge of the soundhole to the bottom of the guitar - a perfect joint in the soundhole area is completely unnecessary and the joint under the fingerboard only needs to be "good enough". For the back plate where a decorative stripe is inlaid between the back halves and a back graft is used the joint needs to be reasonably good, but again - not perfect.
I will admit that having a stationary jointer has made it easy to join the plates perfectly in just a few seconds, so the hand plane and shooting board method has been gathering dust the past several years.

Trued to 2 thou - any error would be doubled when jointing opposing faces, so potentially 4 thou gap or 0.1 mm - I wouldn't risk that.

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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 couple of guitars ago I didn't feel like sharpening my shooting plane and so I used my Stew Mac sanding beam to join a top and I could not believe how quick and accurate it was. I used the plane to hog off the excess and get it close and a few swipes with the beam and it was perfect. So fast and perfect in fact that it's what I use now. But I do both boards at the same time, not one at a time, that way it corrects for any error if the beam is leaning.

Beams are expensive but they are essential in my fretwork now so I would recommend to anyone getting into building or even repair to get one.

I do the same with the SM beam and 180 stickit. Works fine.


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I bought an inch square steel beam at Home Depot, cut it to length (I use 12” for fret leveling), and trued one side on a piece of sandpaper glued to a 1/4” glass plate. It works just fine and you can have any length you want.

I am sure this renders me a woodworking fraud/heretic, but I find hand planes to be an absolute pain in the arse for this particular task. Give me the sanding beam or a jointer any day. I use hand planes for lots of things, but for this task, they just frustrate me. The best results on center seams for me have been with sanding beams. I have a jointer-like machine now (Delta Uniplane), and I will see how well it does. But the sanding beam gives a great result.

This thing is on my Christmas list, albeit a little lower in the priority order. Mostly because I like the idea I can buy that and the track and make something that is on an incline just like a shooting board. It would be fairly economical considering.

https://www.leevalley.com/en-us/shop/to ... em=05Z1510


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I have the Stew-Mac beam but always thought a sanded joint wouldn't be as invisible as a planed joint. I usually do this with a shooting board and #6, but I'm going to do a little experimenting with this method.

OLF sponsor Luthier Suppliers has something specifically made for this btw called the Easy Jointer.

I made the sanding beam I described above for fret work. For jointing, I use a #6 and a shooting board. When it doesn’t work well, I resharpen the plane. That makes all of the difference. I have made a sanded joint when the grain was squirrely I couldn’t plane it, but I think the planed joint is much cleaner.

TBH I've never tried anything except a shooting board and planes, a Lie-Nielsen No.62 and an older Record No.5 with high angle blade in it for jointing plate.
Both planes have been fettled, blades are always freshly sharpened (to 10,000 grit then polished) and final depth setting is about 0.5 thou.
Normal 30 degree blade for softwood and straight grained wood, high angle blade (45 degrees) for any problem hardwoods.
If the edges are a bit wonky I'll use a no 6 to get them close, the go to my freshly sharpened blades in the aforesaid planes.
I check the joint by candling it on a perspex plate with a 24" strip light under underneath.before gluing.
i've had students in building their own guitars who have done a joint in a few minutes if I set up the planes.
This is not in any way a boast, and I admit it took me several tries and quite a bit of plate width initially to get the hang of it, it's just my preferred way of jointing, it just gives me much more confidence doing it this way than sanding a joint.
But whatever gets the pig clean.....

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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’ve done both ways over the years and found that there is zero cosmetic difference provided the joint is nice and tight.