Thread: #1 Acoustic Build

Hi Steve, shocker of a photo but Im sure you get the idea,

Thanks guys, much appreciated.

Well the attempt to bend the bindings across their greater width was pretty much a failure so looks like I'll just wait till the bias binding arrives then strap them up real tight and add a couple of quick clamps to seal the deal in the waist area... In the meantime, the purfling has been completed.

Attachment 154736

Whilst waiting I thought I'd get onto preparing the fretboard. Here's a test piece that I've cut slots into. Should get the real one done this afternoon.

Attachment 154737

Good to get away from the bindings and score a bit of success elsewhere.

The fretboard came up really nice so I'm happy again. It's Mulga with a 16 inch radius sanded to 220 at this stage.

Attachment 154759

Did the fretboard markers today. Nothing fancy, just Abalone dots from Stewmac for the first go.

I only really stuffed up one hole by trying to re-drill it deeper after the first plunge so didn't do that again. Otherwise good.

Attachment 154796

Originally Posted by stevemc32

Another quick question, is there any reason not to glue in the purfling strip first prior to gluing in the binding?

Yes.....securing the purfling while the glue is setting is a p in the a. Easier to fit binding and purfling together...the binding holds the purfling in place while glue is setting. Bear i mind that if youre using a water based glue the purfling is going to swell once you add glue to it.

The teflon strip is really designed for abalone purfling not fibre/wood purfling.

Gluing in binding/purfling together is not that big a deal....if you prebend both then binding tape will hold it in place. I use bias binding tape and binding tape together. I glue up one bout and then wrap the tape around the bout....I then do the other bout. Important to have a clamp and caul over the tail/head block and on a classical the spanish foot.

Cheers Martin

Originally Posted by stevemc32

I only really stuffed up one hole by trying to re-drill it deeper after the first plunge so didn't do that again. Otherwise good.

Try mixing some rosewood dust with epoxy and gluing in dots/markers with same...the coloured epoxy can hide oversized hole etc.

Thanks Martin, I'll keep the epoxy and dust trick ready for the next fretboard inlay work. I actually used CA to glue the dots in and was able to mostly fill the mis-drilling that I did so wasn't too worried about it this time.

My second attempt at binding the back has been just mildly more successful than the first attempt.

Attachment 155067Attachment 155068Attachment 155069

The difference this time is that with the purfling in place I should be able to fill the gaps with a black filler. It's not what I envisioned but should be an acceptable final result.

Would a tinted epoxy be suitable as a filler in this instance or should I go looking for a black wood filler given that I'm planning an oil finish?

looks great there Steve, I had to enlarge and search to find your gap. Filling at work we use plasti bond,it's a good quality filler, and mix with the oxide powders you see in the brickies section at Bunnings. We mix those powders with epoxy as well and I think it is harder, we use it in gappy glue joins on restoration,slight problem is it wants to run out, but if you let it partially set it might be better.probably does not matter, you have gravity on your side there
Rob

Thanks Rob, might try some experiments with the epoxy as I have quite a bit of it here. Have you tried cabosil to thicken up your epoxy when filling joints. It gives the epoxy a cloudy appearance so no good if you want a clear fill but if you're after an opaque colouring it would certainly help with the runniness.

Cabosil , never heard of it, I had a west system type epoxy mix here once that came with a thickener, it was a light yellow powder that could be added to the mix to give it more body, think I threw it years ago when I finished the rest off .
I have been fussing over my neck dimensions, nut width scale length and string spacing ,and trying to get it on a template , how did you get your fret positions, or which method did you use to calculate them ? maths and a digital indicator or the two lines and a compass , Cumpiano calls it the equal tempered interval derivation system ,or another way? Rob

Originally Posted by stevemc32

My second attempt at binding the back has been just mildly more successful than the first attempt.

Hi Steve,

My apologies if you've already covered this but did you bend your bindings prior to gluing them in?

Cheers Martin

Definitely bent those bindings prior to fitting them up Martin. Actually I bent, rebent and bent a little more here and there trying to get them as closely fitting as I could but still struggled with the twist that is introduced as the binding is forced to follow the curvature of the back, not the outline of the back. I'm happy that, with a little bit of filling, it should come up ok so time to get the other side done and move ahead.

Rob, Cabosil is colloidal silica and I think West Systems call it 406 filler. The stuff I have is pure white and is very useful when filling or filleting with epoxy.

I cheated with the fret slots and bought the stewmac notched template. I felt it was too important to get it spot on to risk a silly marking or calculation error. I'm following the plan regarding string spacing and neck width - 45mm at the nut and 55mm at the body join.

The plan called for a 25.4" scale but I've gone with a 25.5" Fender scale as I've played this quite a bit in both electric and acoustic versions and thought I'd stick with it for this one. Not sure a couple of millimeters would make that big a difference over the entire scale in terms of playing so will probably try something different on the next one.

Thanks for the info on the epoxy,we mainly use it as a glue for strong lamination's,

I am sticking to plans with scale length but slightly changing string spacing, slight problem with my plans though, the last fret position in Kinkade ,fret 20 is wrong ,
fret 18 is 417.09 mm from nut
19 is 429.89
20 is 411.97
there is an inch length next to it that seems right and I converted that.

When they printed his book they got his surname wrong on the front cover,he writes about it,I think in the book, or I may have read it on his website ? Front cover Kinkead ,pictures of him in his book wearing T shirt, Kinkade Guitars, I hope the rest of the scale length is right.

I also tried the Campiano, lay out two lines and with dividers and magnification divide the scale length, it said in his book errors compound, and that this is an old way of doing it, by the time I got to the 12 th fret I was 3.5 mm out, and I was being very accurate I thought.

had a look at Stewmacs template might get it as well and check,good also that it has the other scale length on the other side

Martin ,if you read this what ways have you used ?

cheers Rob