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Andyjr1515

Dreadnought Acoustic

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51 minutes ago, Prostheta said:

I hate to say that I told you so, however this was a positive use of predicted retrograde hindsight projection.

That sentence is pure magic. Is there any CCCCC in it?:)

SR

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I've used the home-made rig in action for the first time :)

Before gluing in the binding, I needed to cut the tail-binding slot - I will be doing a simple double strip of binding, where the b/w/b detailing on the binding 'goes round the corner'.  Not a great picture, but I did something similar with my OM Acoustic:

67fFa6hl.jpg 

 

I'm more accurate with a Dremel than with a chisel, but the problem is usually holding the body and some form or routing guide...enter the jig:

uTOXT5sl.jpg

The body is hanging in mid air, held by the jaws of the modded workmate.  Both sides have cork linings so that sufficient clamping can be achieved without leaving any marks on the top.

 

...and done:

9peD0FXl.jpg

Edited by Andyjr1515

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OK - I'm not saying that anyone should apply binding the way I do, but it works for me...and, for me at least, it works much better than using binding tape and/or wrapping.

All I do is this:

1.  I paint on a decent coat of good quality white PVA wood glue onto the body

BwnQhgrl.jpg

 

2.  I paint on a decent coat also onto the beading:

uboVFJYl.jpg

3.  I wait 15 - 20 mins for the glue to dry

4.  I position the binding to make sure it is exactly where I want it

5.  I iron a small length, holding it firmly in place with a cloth until it cools enough to hold fast:

rVb361sl.jpg

6.  I continue round, ensuring each section is fully seated and secure before moving on to the next.

7.  And....well, that's it.  Ready for scraping and sanding.  Total time from the PVA going dry, 7 minutes.  It would have taken me that long to simply untangle the bicycle inner-tube ready for the 'mummy' approach :D :

NpYdg5zl.jpg

tpElVWSl.jpg

 

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Wow, well there you go then. I'm not 100% sure if PVA (or PVAc) glues are without degradation when you reheat them. I'm sure that doing it before the proper final cure makes a difference. Once properly set up I think it's irreversible. Good food for thought.

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42 minutes ago, Prostheta said:

Wow, well there you go then. I'm not 100% sure if PVA (or PVAc) glues are without degradation when you reheat them. I'm sure that doing it before the proper final cure makes a difference. Once properly set up I think it's irreversible. Good food for thought.

Maybe another letter to another supplier :lol:  

Yes, though, I agree - I wouldn't risk it for anything structural where you are relying on the full strength of the joint.  Interestingly, however, it doesn't seem to be hugely affected by full cure - PVA melts with heat whatever and, provided there is enough there to melt in the first place, it seems to remelt, re-merge and re-set in the same way.  Certainly, I've stuck veneer down successfully weeks after originally applying the glue.  

How much the strength is affected by this, on the other hand, is a complete unknown.  We all know that you can remove a fretboard by heating it...but I wouldn't like to try to stick it back on using the same method! ;) 

 

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Well it's a thermoplastic really isn't it? At the very least it can be remobilised but yeah....not 100% convinced about the resetting part outside of light movement and reseating.

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19 minutes ago, Prostheta said:

Well it's a thermoplastic really isn't it? At the very least it can be remobilised but yeah....not 100% convinced about the resetting part outside of light movement and reseating.

Nor am I.  Then again, is it so different to the principle of contact adhesives?  Good bond glue to one surface, good bond glue to the other surface, the only difference being that this is melting the bond of glue to glue rather than a chemical 'tack'.

But the sure and unarguable fact is that I have absolutely no idea...:lol:

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Well, whatever the merits or otherwise, my main concern is 'is the binding going to look OK?'

I think it's going to be fine.  I'm pleased I went with the rosewood rather than ebony (which is a pig to bend) - this is after a quick scrape:

E1Mlnuml.jpg

Wq5nV30l.jpg

 

I think that once the finish is applied and the true colours come out, it's going to look nicely understated :)

Just got to repeat the whole process for the back (no purfling, but the added challenge of the more pronounced curve of the back) and then it's neck, neck, neck!!!

As always, thanks for the feedback, encouragement and debate, folks :)

Andy 

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Regardless of my piddling and overthinking, you're onto something with that method. It's turned out better than nice. It's all shoring up my confidence in finally attacking my own archtop anyway. Keep it up! It'll make me do bad things. 

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On 2/26/2016 at 5:45 PM, Prostheta said:

Regardless of my piddling and overthinking, you're onto something with that method. It's turned out better than nice. It's all shoring up my confidence in finally attacking my own archtop anyway. Keep it up! It'll make me do bad things. 

Nah....it's not piddling and overthinking.  It's correctly testing the validity of the solution in terms of 'Is it a possible solution to an actual problem?  Is it theoretically sound?  Does it work in practice?'

My problem is that, often, I go about that process in reverse order :lol:

So onto the back binding routing and the associated challenges  For anyone who hasn't done an acoustic binding, let me explain.

  • The back is dished much more than the top
  • The angle at the edge of the back isn't, however, equal all around the perimeter - think tangents...where the waist pinches in, you  are closer to the centre of the dish and therefore the tangential angle is smaller than at the upper bout and that is smaller than at the angle at the lower bout.  Basically it's all over the place...
  • So, if you have a relatively large router base , the rise of the back at this angle means that the router rises (the router has to be kept vertical to keep the bearing-guided cut even in width and straight-sided.  
  • Because the angle varies round the perimeter, the router therefore rises different amounts and the cut depth of the binding also varies, that is the bottom of the cut becomes a wavy line, not a straight one.   
  • But the bottom of the binding must be straight for aesthetics and because it wont bend in that plane...you would just get gaps

The short version of the above is "Just trust me.  It ain't gonna work!"

I don't make enough acoustics to invest in the clever (but very cumbersome) Stewmac / LMI rigs.  The precision base with the binding roller fitment won't work for the above reasons.  So I thought I'd try out this from Stewmac:

6atBaB2l.jpg

It's like a mini roller guided precision base.  It is better than the big one because the base is much smaller, therefore the angle of the back at the perimeter affects it less.  It still affects it, but at a manageable level.

When I get round to it, I'll post a review of it but in brief, I'll give it  7 1/2 out of 10:

  • It's a fiddle to set the right height
  • Keeping the router vertical while cutting has to be done purely by eye - not easy
  • You still get variation in cut depth, but it is a smoother transition
  • It did a MUCH better job than my precision base (which is what I used on my OM build)

 

Next job, in between decorating the dining room (I know - ridiculous - it was only done twenty three years ago!) is bending the binding and sticking that on.

Thanks for sticking with it :D  It's appreciated.

 

Edited by Andyjr1515
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Amazing what you can do in an evening when you put your mind to it.

Got the bending iron out and whistled through the last two binding strips.  Got there particularly quickly to the point where they easily fitted into the mould.  What I then do is clamp them to the mould with violin clamps and give them one last water spray before leaving them clamped overnight.  I find it helps prevent the normal tendency to relax the tightness of the curves.

Jh3VIn8l.jpg

Should be able to glue these on in the morning before the dining room decorating starts again!

 

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Not trimmed yet, but all four bindings are now safely on:

F17YqJcl.jpg

 

While the dining room paint was drying, I managed also to get out with my cheapo-cheapo band saw to cut the rough outline of the neck:

0F6zszhl.jpg

 

I'll be using one of the offcuts on the left to stick on to extend the heel to its full depth.

But that's it for today.  Got some serious digging to do next...sadly, not the foundations for a workshop :rolleyes:

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I spent the morning checking measurements and preparing everything for the "Very Scary Bit" - routing the neck tenon and body mortice slot! This one really will be a case of check, double check, triple check, quadruple check before anything is cut.  

I now have built my jig to accurately route a dovetail as well as mortice and tenon, but I don't want to try a dovetail joint the first time ever on a build that matters and one that has a finite timescale.  On the other hand, I have never been overly happy with the dry bolt-on approach I used on my OM.  It works, but it does allow a bit of slack to develop as everything beds in.  That's fine for my own guitar because I recognise when it needs a tweak, but not OK for a build for someone else  

So, I'm going half-way house - I'm going to use a version of bolt-on but glue it too.  Get it all set up,  angles, fit, heel flossing, etc, and then ultimately glue it 

Obviously, the neck will be 30mm shorter once the neck is slotted in, but it's beginning to look like a guitar....

A6yTP10l.jpg

JPdfjePl.jpg

 

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I've been fine-tuning my neck and body routing rig this morning and it's now fully fit for purpose.  As  outlined above, it's a heavily modified B&D Workmate, then heavily borrowing ideas from the LMI / Robert O'Brien jig

The body routing position was already fit to go:

so2yd1Pl.jpg 

 

What I've now done for the neck routing configuration is

  • put the secure micro-adjust for the neck angle (see the black knobs underneath)
  • put a variable pressure clamp to hold the neck (also underneath)

eLBLlahl.jpg

 

The neck is lined up on the angle board by a couple of studs that slot into the truss-rod rout.  A simple carpenters variable angle (pictured) is used for setting the correct angle and the template lines up both with the indicator lines on the rig and also the centre line of the neck.

If we get a bit of dry weather tomorrow, I'm planning to do a first cut!

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Wow, the results speak for themselves. It's clear that you're in control of the process at every stage....I guess you don't allow potential for errors eh?

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51 minutes ago, Prostheta said:

Wow, the results speak for themselves. It's clear that you're in control of the process at every stage....I guess you don't allow potential for errors eh?

:D  It's actually the potential for errors that have so often materialised into real ones that has led me down this path!

Trouble is, it then makes a poor chap overconfident ..... I think I'm going to go for a dovetail after all!!!   I've spent a lot of time over the past couple of days working out how it works and how you achieve the essential offsets and adjustability.  I will do a dummy run with some offcuts but, if that goes OK, then I just might go for it....

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Today's rain (when is it going to STOP?????) was a mixed blessing:

  • it meant I couldn't do anything outside on the summerhouse footings :)
  • it meant I couldn't do anything outside on the guitar :(
  • but that meant I had a bit of time to think through things and experiment.  One was that I remembered that the fixed base  on my little Bosch (Colt) router has an extraction shroud...and I got it to work :)
  • and with it, I realised I could do some modest routing indoors :D
  • and then I remembered that Mrs Andyjr1515 was out this evening <_<
  • which meant that I could do A LOT of routing indoors :wOOt

First I tried the routing jig out on my first ever attempt at a dovetail with some scrap wood, angled at about 3 degrees - in line with my best projection of the target neck angle.

The first attempt at the neck block slot revealed a fatal flaw through a silly oversight (which justified trying it on scrap first!).  The second attempt, though...:

rr7T3JGl.jpg

At that point, I decided that the need to do the real thing while I could remember exactly how I did it was greater than the risk of being beaten to a pulp by Mrs Andyjr1515 for filling the house with wood dust...

I routed the neck heel down to size and popped a 3 degree angle on it - the rig worked a treat! - and did my first 'for real' male dovetail:

HvXTtIHl.jpg

 

Then did the dovetail slot.  Did a simple straight rout well clear of the sides but at the dovetail depth, then changed to the dovetail bit :

RFnkPq7l.jpg

 

To my astonishment and relief....it worked :D

fSkinY5l.jpg

 

Nice tight sides:

Lw9NZ3gl.jpg

 

Angle just right:

U6oUPs7l.jpg

 

And even straight!!!:

HxJbHOfl.jpg

 

What's more, Mrs Andyjr1515 didn't get back until 5 minutes after I'd hoovered up!!!!!!!!!!!!!!!!

For a good while over the next hour or two I assumed I must have simply died and gone to heaven....  :D

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You're seriously in danger of showing us all up here, Andy. :thumb:

I guess Mrs Andyjr1515 isn't a woodworker like my own good lady wife? Nina actually *likes* sanding (and the smell of acetone, which isn't so good) which is an immense bonus to me. I made her do some pin routing last night.

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In between some unavoidable outdoor jobs I've tried to continue small bits of progress.

The main one was to get the dovetail absolutely spot on.  I used Glenn LaSalle's excellent Blues Creek videos as a guide and gently, gently eased everything so that the fretboard was absolutely square to the body, that the neck angle was correct, that there was no movement top or bottom in the dovetail joint itself and that the sides were flossed to an even tight fit to the body.

At the end of all of that, with each adjustment taking a tiny bit of wood off the joint, the resulting joint was smack on, but now a mm or so low.  I had machined the neck slightly oversize, but not quite enough.  No probs, though - I've just glued a strip of hardwood veneer onto one side of the neck joint which has also corrected a small offset in the neck position itself.  It's worked a treat and I'll know next time to allow for a touch more 'wiggle room'.

I'm pleased with the joint.  It's rock solid, and it's in the correct position on all planes:

MXfItekl.jpg

 

The joint has been 'flossed' with 240 grit and, when the joint has its final glues whack, will be firm against the sides all round:

lpNSYn4l.jpg

The end of the fretboard will have the small magnetic pickup that is one half of the Shadow Sonic Doubleplay system.

 

The other thing I am going to try, is to make the pickguard from an offcut of the side lacewood:

1U7uwVBl.jpg

 

 The domestic decorating / garden rearranging chores are mainly done for the time being, so I'm hoping for a spurt of progress in the coming couple of weeks :D 

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This next set of pictures is just for my own record...

...Yes...it's actually SUNNY! :D.  

I know....here in the middle of the UK.  Unbelievable!  I thought it was a UFO at first and it scared the cat for sure.  I passed some young parents down the street saying to their toddlers, "...it's called the SUN.  It's like the RAIN, but not so wet...."

Took maximum advantage and profiled the fretboard:

i3Sody9l.jpg

Note the pencil line which is my 'I've reached where I need to be' reference.  I started on 80 grit then progressively down to 600.

Then - as it STILL hadn't clouded over - added the frets.  On an acoustic I find it a lot easier to get the fretboard pretty much sorted and then glue it on once the neck has been glued to the body.  

I buy coiled fretwire, allowing me to do the 'bead of titebond; position fret; whack one side; whack the other side; whack the middle' technique.  I do three frets at a time and while I'm cutting the next three, I clamp the radius block over the three I've just done for good measure:

Jr6vDe8l.jpg

 

Then laid that to one side for the glue to dry while I started the rough carve of the heelblock:

18gzpFnl.jpg

 Finally, wrapped the trussrod in clingfilm and clamped a piece of the walnut inner splice as a truss-rod cap while the glue dries.  Here I've rough-trimmed the fretboard too:

SdV59eJl.jpg

 

But by now I was worried about getting sunstroke in the 6 degree heat so went back indoors into the comforting gloom...;)

Edited by Andyjr1515

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21 minutes ago, Andyjr1515 said:

...Yes...it's actually SUNNY! :D.  

I know....here in the middle of the UK.  Unbelievable!  I thought it was a UFO at first and it scared the cat for sure.  I passed some young parents down the street saying to their toddlers, "...it's called the SUN.  It's like the RAIN, but not so wet...."

<_<:killinme<_<

SR

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No doubt it'll still be grey and wet though. Simply not AS grey and wet. Are people out in the streets throwing their boots at the hole in the sky, cursing these new fangled ideas?

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5 hours ago, Prostheta said:

No doubt it'll still be grey and wet though. Simply not AS grey and wet. Are people out in the streets throwing their boots at the hole in the sky, cursing these new fangled ideas?

They certainly are!  Do they do that in Finland too? :D

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