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Private member DiscussionTools and Jigs

Non-CNC cauls for Stew-Mac sound hole clamps

I don’t have CNC capabilities so I could not duplicate Dave Slimmer’s version ( https://loothgroup.com/loothprint/bridge-clamping-cauls/). Got a 12x18x1/2 inch HDPE cutting board on Amazon for under $10 (https://www.amazon.com/dp/B001D3LQVA), drilled a row of 1/2 holes about 5/16” deep with a Forstner, cut the HDPE into 5 sided chunks so I could orient by touch, and free handed the brace grooves on the band saw. The clamp swivel pads are 1…

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Yeah, I think the current concerns with microplastics is impacting cutting board prices.
Private member DiscussionAcoustic Builds

Cheap-ish Brace Wood Source

https://www.aircraftspruce.com/catalog/wppages/bargainbag_spruce.php The air craft industry uses 1/4 sawn sitka and this is a box of their "Scrap wood" that is a good value to have on hand, (usually like 36 in long and various width) imo if anyone is in need. It's an odd ball source, but just spreading info. Be well.

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Very cool! Thanks. Bookmarked. That website has some other cool stuff as well.
Private member DiscussionAcoustic Builds

Hide Glue Working Time

I'm using hide glue on this 1st build. So far I've glued up the kerfing, back braces, and the top "X" brace. I'm using the 190 grade glue. Working time is short at best. I heated the top "X" brace surfaces (brace & top) with a blow dryer and that seemed to help, a little. How can I get enough working time to glue the top, and then later the back, without having to rush and creating a real mess in the process? Suggestions and reco…

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I make a "hot hut" out of my go-bar deck by draping a large piece of vapor barrier plastic over it. Use clothes pins, or spring clamps to clamp areas shut around it. I then place a small space heate…
Private member DiscussionAcoustic Builds

Back Braces Shape

So the first real "full build" I'm doing is a Stewmac 000 kit. I was wondering about the back brace shape. I'll was planning to taper the ends at the side joint to about 1.5mm. Should I do some scalloping of the braces? Suggestions and comments are welcomed and appreciated. Regards, Gerry Images

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There's nothing "wrong" with what you have pictured but it lacks some finesse. There are soooo many variables in play to worry about for a first build. If you want to practice some skills in this st…
Private member DiscussionTools and Jigs

Tool for shaving back braces

I am retopping a guitar and while it's open I want to reduce the mass of the back braces. Since the sides are in the way, I can't figure out how to cleanly cut the excess brace wood away; anything I've tried involves the handle hitting the sides and preventing a controlled, clean cut. Is there a tool - say a "pull finger plane" - that I can pull from the edge to the middle of each brace to facilitate this?

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My problem in this parlor guitar is that any chisel I currently have is too long and I can’t address the middle third of the brace without coming in at such an angle that I can’t control the chisel pr…
Private member DiscussionTools and Jigs

Measured drawing and assembly for Proper Variable Radius Sanding Jig

Doug Proper designed a sanding jig that supports variable concave and convex curves, described in the following Loothgroup article: https://loothgroup.com/post-imgcap/the-variable-radius-sander/ I built one and am impressed with how it facilitates preparing bridges, braces and also allows tracing any radius using the chord formula. I made a rough measured drawing and assembly guide to share, with Doug's blessing. First step, ma…

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Ian Davlin
Thank you John !
Private member DiscussionAcoustic Builds

Wood Supplier

Greetings, I was wondering if anyone has expierence with good a supplier for red spruce, preferably old growth, that they would point me to. This would be for acoustic tops/sound boards. From the reading I've done, it seems that the "Adirondack" variety might be the prized piece to get. Haven't decided if torrified is what I'm looking for. I'm also going to need to get brace wood of the same species. Any and all suggestions are…

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Thanks Brock
Private member DiscussionAcoustic Builds

GoBar deck adjustment

Hi folks, I thought you might be interested in this approach to having easy height adjustment for a GoBar deck. I learned this tip from my buddy, Don Parker. He lurks around here too from time to time. :) The basic idea is rather than having a booster platform on the base for use when gluing braces to plates you bring the roof down lower. There is a 3D printed spacer in black in the pics. I linked to a downloadable STL and 3MF of…

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Just FYI, as far as I know, go bars have the same clamping strength no matter how much they are bent. If you want a different level of force, you need a heavier go bar. Or vice versa.
Private member DiscussionAcoustic Builds

Using Maple for Back Inside Center Seam

I just read a small note in a new OM plan (GenOne) I'm using that suggested maple as an alternate wood for the inside center strip between the back braces. Wondering what would be the downside of that (passive back). A curly maple strip would certainly be attractive, and the mass/ stiffness difference is virtually negligible for a passive back. Thoughts? I'm cutting braces this week...

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Flat sawn maple is what all the old Gibsons used for a center strip from the 1920's to the 1970's at least. They are something like .900in wide and .040in thick. It had to have been offcuts of their m…
Private member DiscussionAcoustic Builds

Steam Box Idea... What's wrong with this idea?

Speaking of Trevor Gore... I've started using falcate bracing on my ukuleles and in making the braces, 3 strips of .0625" spruce are bent and then put in a bent lamination glue up rig using epoxy. Bending spruce is no fun on a hot pipe. It's slow, fussy, the fibers want to delaminate. I have been thinking about building a small dedicated steam box. Pulling all 3 of the strips out at once and bending them over a form with a metal back…

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Ian Davlin
I tried it once for trying to bend mandolin sides. This was in 2006, back when the internet wasn't nearly as useful as it is today, so the attempt was pretty incomplete I think. If I remember correctl…