My Second Build

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David Stiles
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My Second Build

Post by David Stiles » Wed Oct 16, 2019 4:44 pm

I have been working on my second guitar build. It is medium sized falcate braced steel string as per the book but I am not attempting a cut away.
Image
I glued the back on today.
Image
It is Camphor Laurel with Silver Ash bracing & linings. Uncoupled resonance is looks like 211Hz which seems OK. I am targeting 214Hz. There is a weaker peak at 150Hz, not sure what that is?

David Stiles
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Re: My Second Build

Post by David Stiles » Tue Oct 22, 2019 1:50 pm

Here are pictures that I tried to attach to previous post:
IMG_20191016_160909.jpg
IMG_20191016_160647.jpg

I have now glued on the soundboard:
IMG_20191021_082543.jpg
I have tap tested the body. I am targeting:
T(1,1)1 90Hz
T(1,1)2 170Hz
T(1,1)3 214Hz

I currently 97Hz, 180Hz, 215Hz with the bridge pins taped over. A little bit concerning is that when I apply 20 grams of blue tack and timber blocks on the bridge position, I get 96,170,213.

I suppose I cannot thin the soundboard edge and will need to keep the bridge very light. My concern is how the application of finish (French Polish) will effect the T(1,1)2 as it's already right on target. Hopefully the stiffness added when the bridge is glued on will give me a little breathing space.

Advice welcome.

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lamanoditrento
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Re: My Second Build

Post by lamanoditrento » Tue Oct 22, 2019 2:14 pm

Nice clean work there. You have to put some finish on and fp is normally thinner than most. Also things change a bit with binding and the neck attached so you may wanna hold one change too much just yet
Trent

David Stiles
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Re: My Second Build

Post by David Stiles » Tue Oct 22, 2019 8:09 pm

Hi Trent, thanks for your reply. "Clean Work" is a very much appreciated compliment for me.

I am trying to figure out whether I am going to be able to achieve a finished T(1,1)2 close enough to 170Hz given I am starting at 180hz closed box. I simply don't know how much effect binding, neck, finish, bridge & strings are going to have. Unfortunately I did not pay attention to this on my first build. Do I have a reasonable chance of making it work or should look at a new soundboard?

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Trevor Gore
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Re: My Second Build

Post by Trevor Gore » Wed Oct 23, 2019 8:22 am

DavidS wrote:
Tue Oct 22, 2019 8:09 pm
I am trying to figure out whether I am going to be able to achieve a finished T(1,1)2 close enough to 170Hz given I am starting at 180hz closed box.
Provided you remove very little wood on binding and clean-up and use a very low mass bridge (< 15 gms), you should be close.

seeaxe
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Re: My Second Build

Post by seeaxe » Wed Oct 23, 2019 4:46 pm

Can't comment on the numbers but that back and those sides are stunning. Going look a million dollars when it's finished. Good luck with your build.
Richard

David Stiles
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Re: My Second Build

Post by David Stiles » Wed Oct 23, 2019 9:41 pm

Thanks Trevor, Thanks Richard, I will carry on and see where it ends up. Started making the bridge today. Padauk with CF. Will be interesting to see if 15g can be achieved.

David

David Stiles
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Re: My Second Build

Post by David Stiles » Mon Oct 28, 2019 8:51 am

I finished bridge and managed to get to 17g. To get down to that, I needed to reduce the footprint a little. It is about 41.5 cm2 which is lower than the book recommendation. I am hoping that's OK given that I have at stiff bridge plate with carbon fibre.
IMG_20191026_172407.jpg
I improved my tapping technique using a pencil eraser and my closed box T(1,1,)2 is 185Hz, a little higher than the 180 I was getting previously. With the bridge attached using really good thin double sided tape I get 182Hz. So, I'm looking comfortable for my 170Hz target. Just wondering if a little bit of edge thinning is advisable?

Dave M
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Re: My Second Build

Post by Dave M » Tue Oct 29, 2019 8:59 am

David that top bracing is incredibly clean. I know just how hard it is not spray epoxy all over the place. Also that Laurel looks rather fine.

Doing cutaways seriously adds to the difficulties but I have decided that the advantage to the player means I should pretty much always do one. Having built a side bender that is fairly reliable for cutaways makes life easier.

I am however impressed with your bridge weight. I really struggle with rosewood to get it down to the level I would like. Have you thinned it down significantly?
------------------
Dave

David Stiles
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Re: My Second Build

Post by David Stiles » Tue Oct 29, 2019 2:53 pm

Hi Dave, thanks for your comments. I am working up to doing a cutaway, perhaps next time.

Bridge is 9mm high at the centre of the front. I have raduised the saddle area to about 20" so it is not as high at the ends of the saddle. At the back it is about 7mm high. The back face is chamfered at about 15deg. Wings about 1.8mm high. Width 34.5 Max and length 151mm Max.

Just hope it has enough glueing area.


David

David Stiles
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Re: My Second Build

Post by David Stiles » Sat Nov 02, 2019 11:25 am

I am open for advice on my bridge glueing area of 41.5mm2. I am considering making a bigger bridge. Currently have a top resonance of 182Hz with bridge taped on. Target is 170Hz so I could accommodate a heavier bridge.

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Trevor Gore
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Re: My Second Build

Post by Trevor Gore » Sun Nov 03, 2019 10:03 am

Your bridge looks the same size as mine (presumably made off the book drawings). Mine stay on! Them peeling off is as much about the bridge plate design as it is about the glue area, and you have the standard falcate bridge plate.

David Stiles
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Re: My Second Build

Post by David Stiles » Sun Nov 03, 2019 4:14 pm

Thanks Trevor. I started with the book dimensions but did take a bit of to get the weight down. I thought it was more but when I look closely it was only 1.5mm off the back and 2mm off each end. That should be within the safety margin.
Regards
David

David Stiles
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Re: My Second Build

Post by David Stiles » Mon Jan 06, 2020 1:26 pm

Hi everyone, I just finished this guitar and I would like to share some of my experiences. Firstly, thanks to everyone who helped me out along the way. The finished guitar sounds amazing beyond expectations. Very happy with it.

In hindsight there are a few lessons:

Closed box T(1,1)2 seemed low at 185Hz so I decided not to do any soundboard edge thinning. After binding, French polishing & bridge gluing I ended up with 178Hz so I added side mass of 800g to bring it down to target of 170Hz. Currently T(1,1)1 is 100Hz and T(1,1)3 is 210Hz. The added 800g makes for a very heavy feeling instrument that will take a lot of getting used to. A bit of edge thinning would have been ideal. Now, I suppose I could remove side mass and then stiffen the back to target 100,180,226 but it sounds so good now I maybe don't want to mess with it..

I made the neck a little chunky. I need to pay more attention to the profile next time.

I scalloped centre of the lower back brace too much and that limited my options. Next time it will be a very shallow scallop just to give me a starting point to work with when guitar is finished.

Anyway, here are some pics.
IMG_20200106_124134.jpg
IMG_20200106_123732.jpg
IMG_20200106_123658.jpg
IMG_20200106_123645.jpg
IMG_20200106_123605.jpg
Attachments
IMG_20200106_123628.jpg

Dave M
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Re: My Second Build

Post by Dave M » Tue Jan 07, 2020 7:10 am

David that looks great. Hopefully the bright red padauk fretboard will calm down over time!

I have said it before but it bears repeating that Trevor's design for that steel string works so well that even we beginners can end up with a good sounding guitar given sufficient care.

Good Stuff. The next one may be better again...

Dave M
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Dave

Woodsy23
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Re: My Second Build

Post by Woodsy23 » Wed Jan 22, 2020 12:25 pm

A fantastic looking guitar and great workmanship. Well done. Only your second? Wow!!!
Richard

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