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  #16  
Old 04-01-2017, 07:23 AM
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Mojo?




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  #17  
Old 04-02-2017, 04:51 AM
emmsone emmsone is offline
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Quote:
Originally Posted by rogthefrog View Post
What's the purpose of the hugiferous post sitting on top of the whole thing?
It was to keep everything in place under pressure, the log probably did fairly little in terms of the actual flattening, that was done by soaking the wood and then clamping with the cauls but the log was just sitting there nearby in the workshop and I thought if I put it on the top it can only help, it was probably mostly psychological in this process....
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  #18  
Old 04-03-2017, 02:47 PM
emmsone emmsone is offline
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Right, so I need some advice.

I went to check on the sides having let them sit for a few days. They were nicely holding in shape, but there are a few issues and this is what I need the advice on before I start gluing neck and end blocks in, it would be good to know how bad the state of the wood is and how badly a mess I've made and if I need to replace the sides?

A) Both sides seem to have significant scorching, this is a bit surprising to me as I was thinking during my last corrective bends that they were almost too wet. Attempts to sand burns out of wood before has taken a lot of effort, and with 2.0mm thin sides, how much can sanding I get away with?

B) I have several large grain splits. I attempted to close these with glue and clamps this evening but they haven't closed completely. I have no idea how bad the grain split can be and it still be useable?

C) around and in the cutaway some obvious 'creases' have appeared. These look far from ideal and I have no idea if these can be hidden/sanded out/fixed/etc? As mentioned the sides are only 2.0mm thick so I don't have huge amounts to play with.

top side with scorching
Untitled by David Emm, on Flickr

cutaway side with possibly worse scorching
Untitled by David Emm, on Flickr

turns out I missed the focus, but here is one of the cracks
Untitled by David Emm, on Flickr

creasing in the cutaway
Untitled by David Emm, on Flickr

creasing and scorching in the cutaway
Untitled by David Emm, on Flickr
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  #19  
Old 04-04-2017, 09:16 AM
Trevor Gore Trevor Gore is offline
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Unfortunately David, I think those sides are cactus. Bending a cutaway in figured wood is quite a big ask of the wood in the first place. Reversing a cutaway in figured wood is next to impossible whilst leaving the sides in good condition.

I've bent a lot of cutaways in figured blackwood - a couple here and here. A few things for next time: 1) Thin the cutaway side to 1.8mm "north" of the waist and keep that constant right up to the end of the side 2) Don't profile the sides before bending. If you get cracks beginning to form, they nearly always start from the edges. If you profile the sides after bending, you have a good chance of cutting out any cracks. 3) Only dampen the inside of the curve when bending. You'll have a lower propensity for fibre starts on the outside of the curve if you keep that side pretty dry. 4) Set the temperature of the bending iron so that you don't get scorching. You'll need to allow more time for the heat to penetrate the wood, but you'll save that time in not having to sand out burn marks. Wood bends a lot more easily than charcoal.

You may be able to rescue parts of your "old" sides for bindings or for laminated linings or even for figured wood purfling. Remember that all the linings, bindings and purfling have to go around the cutaway, too. So have a think about what species of wood to choose for the bindings, if you don't rescue some of the blackwood. You can't thin the bindings in the cutaway area. A final use of the blackwood if all else fails is to use it for headstock facings.

On other subjects, I'd recommend going with the truss rod. I put truss rods in all my classicals, which improves playability significantly. As it's a cross-over, you'll likely be playing with a lower action anyway, so a truss rod will be a big help with the set up rather than having to guess any pre-relief based on no data.

Also (as I think you've already discovered) the sequence of operations for the rosette inlay is to join the top, level the joint, inlay the rosette, level the rosette, then reduce to final thickness by removing wood from the underside of the soundboard. Then cut to outline and finally cut the sound hole.

Good luck!
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  #20  
Old 04-05-2017, 07:34 AM
emmsone emmsone is offline
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Thanks Trevor.

Good to have a second opinion on that. I'm actually not surprised they aren't really useable any more but it is highly annoying though.

I now have to somehow find a new set of sides. The local guy here in Switzerland I bought these from had several sets, but these were the only ones with any flame in, the others were all pretty boring. And also having seen these sides with flame in, i'd really like another set with flame.

In the meantime I'm definitely looking into making an actual bender with a heat blanket. My first bends with the iron went ok (other than being bent incorrectly), but if I decide I can make something more repeatable, something less likely to end up with damaged wood and modifiable to different outline shapes and able to incorporate a cutaway, and all for an un-ridiculous price, i'll be tempted to do that.
It also kinda depends on the availability of replacement tasmanian blackwood sides and that cost involved.

David
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  #21  
Old 04-05-2017, 08:28 AM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by emmsone View Post
... these were the only ones with any flame in, the others were all pretty boring. And also having seen these sides with flame in, i'd really like another set with flame.
It is pretty common that beginning builders want to "hit it out of the park" with their wood selection on their first (or second) guitar. Beginning builders, especially if self-taught, are going to encounter problems and make mistakes - even the most experienced builders make mistakes. Instead, using tried-and-true, easy to work with woods - not the most expensive, not the rarest, not the most exotic - makes more sense. I'm not advocating that beginner's use "junk" wood to build with, but, instead, start with more modest materials while learning the basics of the craft.

Quote:
In the meantime I'm definitely looking into making an actual bender with a heat blanket.
Bending machines are great, but nothing beats the speed and flexibility of a skilled luthier bending over a hot pipe. Bending over a hot pipe is a skill well worth learning, if you have the will to do so.

If you go to my website, http://charlestauber.com/luthier/Resources.html, you'll find some dimensioned sketches of Charles Fox's bending machine - he and George Morris invented it - as it was in the 1970's. Dimensions are in inches, but can easily be converted to suitable metric sizes. That will give you some specifics of bending machine design and sizes. I've used the same bender for the last 30+ years, only last year switching from light bulbs to a heating blanket.

Since then, there are a variety of modifications to the design that have been made by various people. These include substituting the heat source - light bulbs - for heating blankets, modifying the shape of the frame of the bender to accommodate cutaways, using rods on the sliders, rather than springs, cantelevering the press to allow sides to be slid in from one side so that you don't have to remove the press from the body of the bender to install the sides, and a variety of other improvements and variations.

It is a fair bit of work to source all the bits and pieces, make the forms and assemble it all. Buying the controller, probes and blanket won't be inexpensive: it is an investment like any other guitar-making tool.
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  #22  
Old 04-05-2017, 02:55 PM
emmsone emmsone is offline
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Thanks Charles

Quote:
Originally Posted by charles Tauber View Post
It is pretty common that beginning builders want to "hit it out of the park" with their wood selection on their first (or second) guitar. Beginning builders, especially if self-taught, are going to encounter problems and make mistakes - even the most experienced builders make mistakes. Instead, using tried-and-true, easy to work with woods - not the most expensive, not the rarest, not the most exotic - makes more sense. I'm not advocating that beginner's use "junk" wood to build with, but, instead, start with more modest materials while learning the basics of the craft.
Actually thats one of the reasons I went with Tasmanian Blackwood, the research I'd done beforehand was saying it wasn't a particularly challenging wood to work with yet looks good and sounds good. Its also not that expensive, its just not the easiest to get hold of as its not exactly local to Switzerland (my initial plan was to go with Cocobolo but noone would sell me any across borders, plus it was much more expensive and probably a bit too tricky to use for build no. 2 so it was an easy decision not to go with it in the end). I'm not looking for the worlds flamiest sides, i'd just like something with some interest in it.

Quote:
Originally Posted by charles Tauber View Post
Bending machines are great, but nothing beats the speed and flexibility of a skilled luthier bending over a hot pipe. Bending over a hot pipe is a skill well worth learning, if you have the will to do so.

If you go to my website, http://charlestauber.com/luthier/Resources.html, you'll find some dimensioned sketches of Charles Fox's bending machine - he and George Morris invented it - as it was in the 1970's. Dimensions are in inches, but can easily be converted to suitable metric sizes. That will give you some specifics of bending machine design and sizes. I've used the same bender for the last 30+ years, only last year switching from light bulbs to a heating blanket.

It is a fair bit of work to source all the bits and pieces, make the forms and assemble it all. Buying the controller, probes and blanket won't be inexpensive: it is an investment like any other guitar-making tool.
I already own a bending iron, so I'm happy to learn to use it, but it would be handier if I had a tool/device that was less likely to make or create mistakes, especially when i'm likely to make other mistakes more often in other areas but I have to get to those areas first.

Having spent the afternoon investigating, (and thanks access to the plans by the way) the cost of a side bending machine is looking to be higher than I initially thought, mostly because of the temperature controllers. Those things are easily double my guesstimated costs. At this point, due to the fact that I'm going to have to buy more sides, i'm not sure I can spring for a side bender too, that money could/should/probably will go straight towards some decent sharpening stones instead.
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  #23  
Old 04-05-2017, 04:23 PM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by emmsone View Post
... that money could/should/probably will go straight towards some decent sharpening stones instead.
Another less costly option is to use sandpaper, at least as an intermediary solution. Do an internet search for "scary sharp".

A good set of water stones, here, will run close to $200. Oil stones, less. If you use a honing guide with them, another $20 to $200, depending on the one you chose. Sandpaper and a glass or marble plate, about $20 or so to get started.
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  #24  
Old 04-05-2017, 05:37 PM
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There are some inexpensive diamond grit sharpening stones (?) online. Wonder if anyone has any experience with them.
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  #25  
Old 04-05-2017, 06:17 PM
Trevor Gore Trevor Gore is offline
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No need to bother with a bending machine, David. I think your skills on a bending iron are fine if your can reverse a cutaway bend and still have a single piece of wood. There's probably more potential to bend sides wrong in a machine, because you aren't looking at the wood as you're doing it. It's a good building system and a good system of work that prevents you from making mistakes like that.

Investing in sharpening is a good idea. Having tried just about everything, if you want no fuss sharp, diamond plates are the way to go. I use DMT's blue and green coded stones with a Veritas honing guide and nothing else (no strops etc.). Not the cheapest, but no maintenance (like waterstones), fast and you'll only ever have to buy them once.
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  #26  
Old 04-06-2017, 02:23 PM
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Rodger Knox Rodger Knox is offline
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Quote:
Originally Posted by emmsone View Post
Having spent the afternoon investigating, (and thanks access to the plans by the way) the cost of a side bending machine is looking to be higher than I initially thought, mostly because of the temperature controllers.
A side bender doesn't have to be that elaborate or expensive. Scroll down the second page to see how I bend sides. It's cheap to build, and works fine. I use light bulbs and a clothes iron for heat. I also have a bending iron, and frequently do the waist on the iron and the bouts on the bender. I built this when I couldn't afford a heating blanket and controller, but it works so well that I still haven't bought a blanket, even though now I could easily afford it.
http://www.luthiersforum.com/forum/v...37283&start=25

By the way, that's bloodwood, which is very difficult to bend.
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  #27  
Old 04-06-2017, 09:12 PM
Quickstep192 Quickstep192 is offline
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Rodger,

The pictures on that site are only available to members, but I'd very much like to see your bender. Would you be kind enough to post them here?
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  #28  
Old 04-07-2017, 11:52 AM
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Sure...

Wiring:

With a bending form (this one is an L-00 shape)

Bending the upper bout:

Right after bending:
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  #29  
Old 04-07-2017, 05:11 PM
Quickstep192 Quickstep192 is offline
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Rodger, Thank you very much.

Simple and effective. What's not to like!
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  #30  
Old 04-11-2017, 02:00 PM
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Rodger, thanks for those bender pics. Budget dictates that I can't even bodge one together at the moment so its out at least for this build.


Hopefully i'll find out in the next day or so about the options/availability of replacement tasmanian sides but in the meanwhile i've been keeping myself somewhat occupied with the rosette.
Last time round I just bought a pre-cut walnut rosette from LMI, this time I wanted a Tasmanian blackwood one to go match the back and sides so I got hold of some flamey pieces and assembled one myself.
As previously mentioned, I should perhaps have installed the rosette before thicknessing the top as doing it this way round doesn't give you much leeway. Its a long way from impossible though and i've managed to do it, but you have to be very careful.

I have to say, shelling out for the Stew Mac dremel router base and circle cutter made this job WAY easier then using the stupid, all plastic, wobbly, decidedly unaccurate router base actually made by Dremel. Although it was expensive, it was clearly money well spent.

Here's the process in picture form

First step of the rosette, cutting pieces to a 22.5 degree angle to give me 16 pieces that would go together to make a complete circle. I did this by clamping a 22.5 degree wedge onto a small piece of tasmanian and then using this as a straight edge for the japanese saw to cut the pieces to correct size, shape and angle.
Untitled by David Emm, on Flickr

Second step was gluing these pieces together. I put brown parcel tape across the board hoping that superglue wouldn't stick to it so well. Well it did stick, but it was possible to peel it all off eventually without leaving any stuck to the bottom of the rosette.
Untitled by David Emm, on Flickr

Routed the rosette to the dimensions I wanted.
Untitled by David Emm, on Flickr

Routed the channel in the soundboard for the rosette, I left this shallower then normal, barely 1mm deep and did extra scraping to level it afterwards.
Untitled by David Emm, on Flickr

Rosette glued in place.
Untitled by David Emm, on Flickr

Rosette being scraped to be level with soundboard
Untitled by David Emm, on Flickr

Rosette scraped level with the soundboard
Untitled by David Emm, on Flickr

Rosette installed and soundhole cut
Untitled by David Emm, on Flickr

soundhole cut and rosette installed in the soundboard
Untitled by David Emm, on Flickr
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