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Hi,

Just wondering who likes a back strip or who joints the back without one.

I have always used one but i think the rosewood i have now will look nice without it, do i just glue then dust fill with CA glue?

Any opinions on the best looking arrangement

Cheers

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Pier fill the inside ?


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I personally don't like back strips for two reasons. First, if the wood has any book matching character (flame or interesting grain or sap wood) I think a stripe down the middle spoils it. Second, I like to carry a theme thru all of the trim on my guitars - binding and rosette and back stripe and anything else should be similar materials and colors. Most commercial back stripes just don't fit into this.

(I know there are exceptions and I expect to see a bunch of beautiful back strips in the next few posts, but for me, no thanks)

Of the four, I like number 2 the best.

Properly joined should not need CA dust fill, or did I misunderstand?

Anyway, I prefer without.

I liked back strips when the instrument I copied had one.
If it's a good back like this one, not.
I prefer #4. The grain is the straightest and flows the best. One and two are not as good of glue joint. Some end grain there...

Depends on the rest of the design, but usually I prefer no strip.

I like arrangements 3/4 better than 1/2. This back would look great with or without a strip, but the decision will make the difference between a soothing gradient all the way across, or a striking appearance as the gradient would increase contrast with the strip.

I only do back strips on request these days. The industry has been slowly migrating away from them and that's fine with me. I never liked installing them. But, as in most things guitar, some like it some don't.

As far as your back goes I am leaning toward #2, but 3 & 4 are more traditional and appear to be higher quality wood with the darker/straighter grain showing.

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Joe Beaver
Maker of Sawdust

I'm about 50/50 on back strips. I like them just as many times as I don't like them. One can argue that they make a better joint too. If I am not mistaken in classical guitar tradition a marquee strip was used so that when wood moved in the future the back strip would sort of be flexible with it. If you rout the back strip in place then you are essentially making a lap joint which may or may not be better. Like anything in guitar building it depends on who you ask

I'm not sure what you mean by fill with CA dust, fill what? The back and top joints of the two plate halves are very important to get perfect.

If the figure looks cool together I don’t use one. If I do I have just been using a strip of the same wood without purfling. It can look understated and classy. That seems the strongest when routed in to form kind of a T joint. Many times just 1/8” wide.

When I would try to snap the off cuts of a back with a decorative back strip they always broke along a purfling line

Here is a plain Maple back strip on a Bird’s Eye back. It looked cool under finish.

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Sometimes I use back strips and sometimes I don't. It depends on the character of the wood. Some guitars look better with a strip dividing the back and some don't seem to need it. Back strips and purflings can help you "grow" the width of the back and allow you to use a piece of wood that would otherwise be too narrow.
For the sets you are have I would match the straight grain to the center and depending on the binding scheme use a back strip or not. To me, the curved grain matched to the center just looks like a lower grade of EIR and isn't interesting enough to be worth showing off. But that is just an opinion and you should do what suits you. Things that were once seen as less desirable are sometimes seen as more desirable these days.

Are you hoping to close those gaps with CA and dust rather than jointing it properly?

I like something, a small detail like the quartered maple strip between the birdseye balances everything out, nicely done BTW.

Sharpen up your plane and join these properly, no CA and dust

Like many here, sometimes I use them, sometimes I don’t. When I use them, I sometimes just use a piece of binding. For instance, maple binding on rosewood back and sides, no side purfling. It ties it all together very nicely. But the rosewood backs I have done without a strip look great, too.

That's cool Terrence I've never seen anything like that before.

Hmm might of been taken out of context a bit, will joint it to the best of my ability but i imagine its difficult to not get the odd tiny gap, but maybe i need to het the technique a bit better, im looking into buying a stanley no7 when money allows, for now im sanding them upright on a piece of glass and getting okay ish results.

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There should be no gaps at all when jointing the plates. We use a process called candling to verify that there are no gaps. If you have a light table that's great otherwise you can hold the pieces together and shine them up against a bright window or good light source to look for any gaps. It can be a real PIA especially when you first start but eventually you build up skills with a hand plane where after candling and you know where the gap is you can adjust the pressure. You need to make a shooting board and stack the two plate halves in a book match and cut both at the same time. Ideally you would produce two perfect ribbons of wood and be good to go but in the real world it's different.

But do yourself a big favor and don't settle for less on this joint. If you are desperate and there is a little light that you know will be covered by the head and tail block or even where the sound hole will be cutout then maybe that is acceptable for now.

You can use a flat surface and PSA sandpaper on a level to get a perfect jointed top/back.

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Tim Benware
Creedmoor, NC

That will work provided the level is truly flat. Mine is only flat on one side.

Getting that perfect joint with a handplane can be tricky, there is a lot of feel to it and it is difficult to explain. If it has been a while since I've done it, it takes me a little while to get the feel back. I always start with the widest plate (top or back) so it can come back to me on the plate with the largest margin for error Sometimes it takes a while, sometimes it's really quick.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Somebody told me once to never use anything over 150 when doing the sanding method or the joint might not glue properly. I don’t know if that is true or not, but I use 150 on the long SM leveling beam if I use the sanding approach.

If the plate set has little to no margin for error I will usually run them through the power jointer and then use the sanding technique to dial it in. Honestly, it’s probably fine right off the jointer.

One day my plane skills will get there.

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Maybe hand plane is not the way to go for me yet, where could i get a long beam from that would be calibrated

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I got a slab of milled marble from a countertop place. 4x36. I run my resaw fence hanging off the shooting board as a fence, and run the joint along the slab with sandpaper on it. Lots of things work.

I've seen boards with a straightedge attached to run against a downcut flush bit on the router table, some have CNC, lotsa things.

Now, I would never suggest aiming for less than perfection, but...

If you're putting in a backstrip, if you get your back joint mostly perfect with only very minor gaps, then inlay the back strip, not sandwiched in, and reinforce it on the inside with the standard spruce crosspatch, that works too.

But getting a system of joinery down is not that hard, and quite important.

Your glass should be flat unless it is not supported well and flexing while you use it. Are you sanding both halves at the same time with the book match closed? One thing that having them flat (like on a shooting board or how Brad uses his sanding beam) is that it will prevent you from tipping the plates from side to side as you sand. Doing them together with the bookmatch closed, cancels out any error from 90 degrees but it won't save you from "rolling" the edge and rounding the corners of the joint off. That can make it difficult to tell if you have a good joint.

I know you are saving for a number 7 but do you have any good handplane? If so, you should learn to set it up for a fine cut and practice. You don't need a No. 7; the length is nice but that may be a bit too long for some tastes. You can get the job done on a guitar sized plate with a no. 5. I picked up a no. 6 and that seems like just the right length for me but I could have happily gone on with the 5.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

. "You need to make a shooting board and stack the two plate halves in a book match and cut both at the same time. "

As jfmckenna said you need to make a shooting board. Then with almost any sharp well set plane (#4 and #5 commonly) you can plane a good joint. You might even find a #7 to be a bit cumbersome. A shooting board eliminates a lot of the skill needed to plane a joint freehand - and isn't that why we "jig up" - to make the work easier and a bit more certain.
A planed joint is far superior to a sanded one.

For me, it's plane and shooting board. Lacking a sharp plane or skills to effectively use one I would buy
a little rig like the one Luthier Suppliers sell or build something similar.
http://www.luthiersuppliers.com/products/p11.html
Just looking at the pictures is enough to figure out how to go about it.
Ken

The very first guitar I ever built I used sand paper on a level as per Sloans book. It was an alternative to using a plane. It took me 3 hours and I could NOT get it right. Then I decided to get a plane and try that and in about 30 minutes I was done. Now I can do it in about 10-15 minutes. But honestly I found sand paper to be impossible to use.