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  #31  
Old 07-19-2016, 12:35 PM
emmsone emmsone is offline
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So did a few quick bits and pieces on the build today, modified my dremel router base so i could rout for and glue in the rosette which I did, glued in linings on the top edge

Dremel router base mod, cut a chunk out of the base which allowed me to insert a block which moved the centre-point pin much closer to the cutting bit allowing a much tighter, and now small enough to be usable, circle.
Untitled by David Emm, on Flickr

Superglued a block of wood to the plastic mount to move the pin allowing a smaller circle than the base allows as "standard"
Untitled by David Emm, on Flickr

Routed the channel for the rosette to sit in
Untitled by David Emm, on Flickr

Glued the rosette in with a bwb purfling on the inside of the ring, i actually wasnt planning on this, but the router base is SO unstable my "circular" channel was noticably "Oval" so i scraped the inside edge with a chisel and sanded the inside edge of the rosette until it fit. Ideally I would have put the purfling strip on both sides, but I didn't trust the router to do a good enough job to cut the small gap for the purfling on the outside of the rosette so I left it as is, I actually quite like it like this. It was left slightly proud and glued with a small weight on it. I'll scrape it flush to the soundboard tomorrow.
Untitled by David Emm, on Flickr

Then glued the linings in using rubber bands on the plastic pegs for extra clamping power!
Untitled by David Emm, on Flickr

Tomorrows job planning includes cutting the soundhole out, gluing the liners on the other side and gluing the braces to the soundboard, i'll end up gluing them all on as 'large' blocks and then scallop and shape them with a chisel afterwards, a bit of a pain and a bit more risky but something that has to be done when you don't have go bars.
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  #32  
Old 07-21-2016, 12:52 PM
emmsone emmsone is offline
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Did just an hour in the workshop today before it was closed up so I had to leave
I scraped the rosette flush to the soundboard and glued the linings onto the other end of the sides.

scraping the rosette, i've decided I love scrapers, this was my first use, i'm definitely a convert now.
Untitled by David Emm, on Flickr

final result of the scraping
Untitled by David Emm, on Flickr

gluing the linings on the other side
Untitled by David Emm, on Flickr

linings glued in
Untitled by David Emm, on Flickr
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  #33  
Old 07-26-2016, 09:41 AM
emmsone emmsone is offline
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So a few updates on the build

Got the soundhole cut out, the linings are now glued in on both sides, today I glued the braces on using my home madebrace gluing device seen below, I'm 100% convinced it would be easier to shape the braces first and then glue them on using go bars, but not only do I have no fibreglass go bars, i couldn't even find any suitable wood that would bend without breaking. So i went with the "glue-them-all-on-at-the-same-time-with-them-all-the-same-height-and shape-them-all-afterwards" approach.
I was planning to clamp the small side braces in as well today but I forgot to take enough bracing wood to do that.
DHL says my radius dish will arrive tomorrow, so that means I can hopefully get the back braced up soon too!!!

Soundhole cut out, the edge was sanded after this was taken so it looks a bit tidier.
Untitled by David Emm, on Flickr

X brace notched and glued together, its actually pretty solid and tight, its just the pencil marks that make it look like theres a gap on the photo
Untitled by David Emm, on Flickr

All the braces in place ready for gluing
Untitled by David Emm, on Flickr

Home made brace gluing device in action. Just about the right weight so all the braces get good downward clamping pressure, and not so heavy as to squash the soft spruce soundboard or leave dents from the weight
Untitled by David Emm, on Flickr

Side view of the brace gluing device
Untitled by David Emm, on Flickr

Took the guitar out of the mould for the first time! looks like a guitar and held together nicely.
Untitled by David Emm, on Flickr
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  #34  
Old 07-26-2016, 12:58 PM
TEK TEK is offline
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David,
Looking great so far!
It doesn't appear that you built a radius into the soundboard. It is a good idea to do so for strength and it will help minimize change in humidity affects to the top. Less likely to crack the top if the guitar gets too dry.
Travis
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  #35  
Old 07-26-2016, 02:03 PM
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Rodger Knox Rodger Knox is offline
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Quote:
Originally Posted by TEK View Post
David,
Looking great so far!
It doesn't appear that you built a radius into the soundboard. It is a good idea to do so for strength and it will help minimize change in humidity affects to the top. Less likely to crack the top if the guitar gets too dry.
Travis
Don't worry about the flat top, many builders do it on purpose. String tension pulls a little dome into the top, even if it's not built in.
Those braces look pretty big, but the top is pretty thin.
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  #36  
Old 07-26-2016, 02:23 PM
emmsone emmsone is offline
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Quote:
Originally Posted by Rodger Knox View Post
Don't worry about the flat top, many builders do it on purpose. String tension pulls a little dome into the top, even if it's not built in.
Those braces look pretty big, but the top is pretty thin.
Thanks Roger,
Yea, i'm not massively concerned about the flat top, it was my thought to do that way and thats also what the plans said. i'm a bit uncertain about how exactly i'm going to put my neck angle in, and a radiusssed top would make that even more confusing.
I agree, the braces are all big, but thats because they are all oversized vs how big they would be at the biggest point so they would all be able to be glued at the same time. they are 8mm wide for the X and longer braces and 6.5 on the 4 small outer ones and right now they are all 18mm high, but they will all be cut down A LOT to get them to the dimensions and shapes on the plans i have.
in case you're interested, the soundboard is at 2.8mm, i don't plan on taking much more if any off that other than whatever finish sanding does.
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  #37  
Old 07-26-2016, 02:37 PM
LouieAtienza LouieAtienza is offline
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David,

Great job so far! As Rodger says, the top doming is not a necessary feature. It can allow a stiffer top, but the top plate may have to be thinned some more and the braces radiused and thinned further than a flat top to compensate for the stiffness the doming naturally lends.

I actually do use a flat workboard to glue my braces. For a guitar I intend for fingerstyle, I also use a slightly thicker fretboard than normal and I have a zero neck angle. For a flat-picked guitar I sand a 1degree angle from the neck block to the upper transverse brace before I glue the top down. Unbeknownst to me until recently, this is how Martin does it.
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  #38  
Old 07-27-2016, 01:38 AM
emmsone emmsone is offline
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Quote:
Originally Posted by LouieAtienza View Post
David,

Great job so far!
For a guitar I intend for fingerstyle, I also use a slightly thicker fretboard than normal and I have a zero neck angle. For a flat-picked guitar I sand a 1degree angle from the neck block to the upper transverse brace before I glue the top down. Unbeknownst to me until recently, this is how Martin does it.
Thanks Louie.
Also, thanks for mentioning about the neck angle, if i understand correctly and having just watched a martin youtube video, with sanding that top section at an angle combined with the complementary angle cut into the end of the neck/neck joint, i should be good! Bonus. One less thing to worry about!
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  #39  
Old 07-27-2016, 08:21 AM
emmsone emmsone is offline
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The workshop was only open for 2 hours today so didn't get as much done as i'd like. I decided to carve the braces on the soundboard. I was using a chisel, its not a tricky task really but although i'm not finished (still have the 2 main X struts to carve and the 2 small ones on one side, the ones i have carved look awful.
I still have to triangularise the braces and sand them smooth, but even so, can't say i'm liking my current shapings. Score -1 to gluing the braces on first....

I had a clever plan of attaching a clip on tuner to do some tap tone testing once the bracing is carved down to the shape give on the plan and then i cut out the shape a bit closer to the line.
Weirdly, despite using the same template to create the mould and draw the outline on the soundboard/back, when I overlay the template on the bent sides (which fit inside the mould) the sides seem to be wider than the template all the way around!

I was hoping to have the box closed this week, but unless I can get 2 full days in the workshop (who knows, depends how long its open tomorrow and if its open at all or not and for how long on friday) thats not looking likely now.

Here's the soundboard brace carving I managed to get done this morning.

starting point
Untitled by David Emm, on Flickr

end point view one
Untitled by David Emm, on Flickr

end point view two
Untitled by David Emm, on Flickr
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  #40  
Old 07-27-2016, 03:27 PM
LouieAtienza LouieAtienza is offline
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Looking good, David!
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  #41  
Old 07-27-2016, 03:35 PM
charles Tauber charles Tauber is offline
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Your brace carving looks fine. Nothing substandard about it.

It is much easier to drill the hole for the truss rod nut before gluing the brace, however.
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  #42  
Old 07-28-2016, 02:43 PM
emmsone emmsone is offline
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Managed a few more hours work today. No chance of closing the box this week and with the workshop closed from tomorrow afternoon until the end of next week, thats a bit annoying.

Anyway, today I finally made use of the radius dish I gave in and bought to brace the back. Added the centre seam reinforcing strip first, then chiseled out the slots and then after using sandpaper in the dish to pre-radius the underside of the braces, glued the braces down once again using my "put a board on top of all the braces and add some weights on the top" technique.

I didn't have enough time to do the back and finish the soundboard bracing carving, but i did at least get them all shaped to where the are supposed to be, now they just have to be triangulified.

centre seam reinforcing strip after being glued down and slots chiseled out
Untitled by David Emm, on Flickr

back bracing sitting approximately in place before being glued down
Untitled by David Emm, on Flickr

my gluing device in action again, this time aided by some clamps to get the pressure in the right areas of the "dish" shape using the weights on the top.
Untitled by David Emm, on Flickr

a bit more brace carving
Untitled by David Emm, on Flickr

I did start to triangulate one brace and it does look better when its like that.
Untitled by David Emm, on Flickr

another view of the triangulation
Untitled by David Emm, on Flickr
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  #43  
Old 07-28-2016, 04:00 PM
LouieAtienza LouieAtienza is offline
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You SURE this is your first?! Looking great!
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  #44  
Old 07-29-2016, 11:15 AM
emmsone emmsone is offline
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Quote:
Originally Posted by LouieAtienza View Post
You SURE this is your first?! Looking great!
Hahaha, thanks Louie! yep, its my first acoustic. The first guitar I built was a bass and I finished that earlier this year. (pictured below)

What I have found with this build is that despite the fact that for this current build i'm working in a public access workshop, which annoyingly mostly means I can only go when its open and is completely ruining any schedules i may have in my head, the fact there are good tools there, a large bandsaw, a good belt sander, table saws, a massive and excellent jointer, a thicknesser that does almost as good a job as a lot of sanders, a table router, plenty of clamps, sharp chisels etc all makes the build less complicated. I can concentrate on what I have to do and less of how to make a tool not designed for the job do something else.
The bass guitar was pretty much built in a garage with 6 tools (a hand saw, a drill, a router, an angle grinder (neck/belly cut/arm bevel), a rasp and sandpaper. There are things in this acoustic build i'm not sure how to do, but i'm not doing so much experimentation and inventing solutions, i'm just finding the right tool for the job, or at least the closest and using that.

The workshop is actually closed for the next 10 days so in the meantime i'm going think through the upcoming tasks to do and mostly to try and work out and get in my head how exactly i'm going to execute the dovetail neck joint and while doing that keep the neck completely straight and aligned.....


here's the bass i built, Zebrawood, Sapele and Maple with Mexican Bocote fretboard
Bass guitar for reference by David Emm, on Flickr
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  #45  
Old 08-03-2016, 03:18 PM
emmsone emmsone is offline
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So as the workshop isn't open this week, i've been doing some thought prep on how i'm going to do some things next week when i can get back in.

The dovetail neck joint....
The angle of the triangular shape, does this need to be a specific shape? or as long as the shapes match on both the neck and body it'll be ok? It seems all the templates, stewmac, lmi and others i've seen, all use the same angles, is there a structural reason for that? or just tradition?

In one of the current Kostal threads I saw the way Mr Kostal does his neck joint with a pinned mortice joint. I quite like this idea for its simplicity, but I don't have the "extended L shape neck block" like he does so the whole strengthening via elongated graphite strips that run over into the body might not work for me when I have a smaller neck block holding the joint together.

I've got to sort out how to get the angles on the back right, i'm leaning towards the "driving the bus" in the radius dish sanding technique, but I don't know if that will work when I have bigger gaps to the dish then I planned, perhaps my side templates weren't cut as accurately as i'd hoped.

I'd also like to find a way to 'reference' the tap-tone of my soundboard just before its glued in (other than using memory) so when my next build comes along i'll have a point to work from as I don't have any point of reference for this one, its just hoping the bracing and soundboard thickness dimensions given in the plans work out good.
Any ideas how I can do this without investing xxx thousands of dollars of sound analysis equipment? would an iPhone recording be good enough? i'd say no, but its my only idea right now.

thanks for all the help as usual

Dave
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