Search found 94 matches

by Chuck Morrison
Tue Jan 21, 2020 1:28 pm
Forum: Flat-Top Acoustic Guitars and Bass Guitars
Topic: Double top all-wood acoustic
Replies: 13
Views: 3743

Re: Double top all-wood acoustic

I've been building double tops for a six or seven years now. I appreciate seeing how you've done the CNC work on your wood DTs, and had conversations with builders who have been doing that or talked about doing it, but I haven't had the opportunity to see one or try it myself. My concern about doing...
by Chuck Morrison
Mon Dec 16, 2019 3:45 pm
Forum: Tools and Jigs
Topic: Thank You Alan!! (Ultimate Scrapers)
Replies: 15
Views: 4601

Re: Thank You Alan!! (Ultimate Scrapers)

Thanks for the tip Alan, Oddly enough it didn't take long at all to get the original sharpening gouges out with the skate sharpener and it went right to the edges quickly, so It doesn't seem that far off of the original curve in spite of the small diameter. Maybe some slop in my technique is a bette...
by Chuck Morrison
Thu Dec 12, 2019 3:03 pm
Forum: Tools and Jigs
Topic: Thank You Alan!! (Ultimate Scrapers)
Replies: 15
Views: 4601

Re: Thank You Alan!! (Ultimate Scrapers)

After reading this thread I bought a skate sharpener and a few cheap sharpening stones. The sharpener (with 2 grit sizes) and the round stones have the same diameter, about 1/2" and the right size for the scraper. Although it took a while to get the original deep scratches out of the hollow edge, th...
by Chuck Morrison
Fri Dec 06, 2019 12:26 pm
Forum: Wood and Materials Q&A
Topic: Scheller Tuners
Replies: 2
Views: 1838

Re: Scheller Tuners

I thought they looked nice and asked for a quote. They are 2x to 3x the price of the Rubner "roll" tuners I usually use. I may try a set some day just to see ...
by Chuck Morrison
Fri Oct 25, 2019 6:55 pm
Forum: Flat-Top Acoustic Guitars and Bass Guitars
Topic: Double sides
Replies: 34
Views: 20748

Re: Double sides

Matt Atkinson wrote:I imagine laminated sides have very little springback?
In the case of the fully kerfed sides I show above, yes. I'd say none actually since it was glued together in the form and it still fits closely into the form even with top and back attached.
by Chuck Morrison
Tue Sep 24, 2019 7:05 am
Forum: Flat-Top Acoustic Guitars and Bass Guitars
Topic: Double sides
Replies: 34
Views: 20748

Re: Double sides

Hi Darren, Thanks for the detailed description and the photos. Definitely worth more than 1000 words in this case. 5 layers of .5mm veneer is 2.5 - 3 mm + whatever glue adds. I got away with 3 layers on a guitar I built to be ultra light (1.5mm). What did you use to glue the birch veneer onto the po...
by Chuck Morrison
Mon Sep 16, 2019 2:08 pm
Forum: Flat-Top Acoustic Guitars and Bass Guitars
Topic: Double sides
Replies: 34
Views: 20748

Re: Double sides

I'm going back to a previous discussion rather than starting a new one, not sure which is proper protocol. I've done double sides in the past layering up veneers, but I never felt like that was doing what it was supposed to, which is giving a more solid foundation for holding the soundboard and redu...
by Chuck Morrison
Thu Aug 08, 2019 5:52 pm
Forum: Flat-Top Acoustic Guitars and Bass Guitars
Topic: Double top glues ?
Replies: 4
Views: 1588

Re: Double top glues ?

My guess is that water soluble glues won't stick as well to the Kevlar/phenolic Nomex. Other than that I can see no reason not to use it in a guitar. The Kevlar stuff is water and heat resistant, which is useful in automotive and aviation applications, but we don't need it. That could be an issue, ...
by Chuck Morrison
Thu Aug 08, 2019 5:44 pm
Forum: Flat-Top Acoustic Guitars and Bass Guitars
Topic: Double top glues ?
Replies: 4
Views: 1588

Re: Double top glues ?

Why is foaming a bad thing? It shouldn't make any difference in the weight and might even add to the stiffness. I can't imagine that an area filled in with PU foam would have the same acoustical properties as one filled with just air. but if they were all filled in, what would that do ? I don't kno...
by Chuck Morrison
Wed Aug 07, 2019 12:32 pm
Forum: Flat-Top Acoustic Guitars and Bass Guitars
Topic: Double top glues ?
Replies: 4
Views: 1588

Double top glues ?

I've built quite a few double top guitars (sheets of spruce/cedar with Nomex) using T-88 epoxy with a lot of success. These tops have been measurably lighter and stronger than their solid wood counterparts. They also take considerably longer to build. I've used techniques as described by Alan Dunwel...
by Chuck Morrison
Fri Jul 05, 2019 7:03 pm
Forum: Glues and Finishes
Topic: dealing with drips and fish-eye with WB finishes
Replies: 17
Views: 3852

Re: dealing with drips and fish-eye with WB finishes

OK, I just put the last coat on the recalcitrant rosewood back. Since I had a previous coat of several weeks old sanding sealer and a few coats of top coat that had gone so poorly, I sanded all that off down to the wood and started over again. I used the crystalac sanding sealer again, used some LMI...
by Chuck Morrison
Wed Jul 03, 2019 8:44 pm
Forum: Glues and Finishes
Topic: dealing with drips and fish-eye with WB finishes
Replies: 17
Views: 3852

Re: dealing with drips and fish-eye with WB finishes

True, but the grey silicon carbide papers tend to be coated with some form of stearate, which apparently can cause fish eye in varying degrees. It is used as a lubricant, keeping sanding dust from adhering to the sandpaper particles. The "silicon" in silicon carbide abrasives is silica, the mineral ...
by Chuck Morrison
Wed Jul 03, 2019 6:58 pm
Forum: Glues and Finishes
Topic: dealing with drips and fish-eye with WB finishes
Replies: 17
Views: 3852

Re: dealing with drips and fish-eye with WB finishes

All good advice, and I have been cleaning up the shop as much as I can before brushing anything. However, I don't think that is the story. In this case I have one surface, a EI rosewood back, that is giving me fits. The Cedar top is no problem and the grenadillo sides are coating very nicely. The on...
by Chuck Morrison
Wed Jul 03, 2019 2:56 pm
Forum: Glues and Finishes
Topic: dealing with drips and fish-eye with WB finishes
Replies: 17
Views: 3852

Re: dealing with drips and fish-eye with WB finishes

I have tried really hard to keep silicone out of my shop. In the past, when I’ve had fisheyes appear, I have washed the area with alcohol and put on a shellac coat. Usually that removes the fisheye tendency. I have limited myself to the yellow sandpapers—either 3M or Mirka. If any of these are stea...
by Chuck Morrison
Wed Jul 03, 2019 12:33 am
Forum: Glues and Finishes
Topic: dealing with drips and fish-eye with WB finishes
Replies: 17
Views: 3852

Re: dealing with drips and fish-eye with WB finishes

My experience with witness lines is that they tend to buff out to nothing when I get to a full on gloss. I haven't tried this with Brite tone yet, but I'll get to test that on this most recent build since I finished the top before I put the back on (including no binding yet on the top) so I could pu...
by Chuck Morrison
Tue Jul 02, 2019 1:24 am
Forum: Glues and Finishes
Topic: dealing with drips and fish-eye with WB finishes
Replies: 17
Views: 3852

Re: dealing with drips and fish-eye with WB finishes

Thanks for the comments, everyone. Yes, I've seen the cautions about the amount of water to add, but in my experience it didn't really change the viscosity as much as I was hoping. I still have an issue with stiff surface tension, and adding water won't change that. At times this can result in nasty...
by Chuck Morrison
Sat Jun 29, 2019 1:44 pm
Forum: Glues and Finishes
Topic: dealing with drips and fish-eye with WB finishes
Replies: 17
Views: 3852

dealing with drips and fish-eye with WB finishes

I've been experimenting with water borne finishes for several decades. After KTM9 tragically disappeared I tried several alternatives and have for now settled on the crystalac brite tone finish, although I find their pore filler to be largely useless. Over the years I've tried Miniwax, Delft, Genera...
by Chuck Morrison
Wed Jun 26, 2019 2:02 pm
Forum: Flat-Top Acoustic Guitars and Bass Guitars
Topic: Thicknessing back and sides with a jointer
Replies: 17
Views: 7147

Re: Thicknessing back and sides with a jointer

I have an old (early 80s vintage) INCA 8" jointer with a planer attachment. I used it quite a bit over the years to thickness all the woods I used. It worked OK but like all straight blade jointers and planers , you have to be careful of the grain direction, especially on thin pieces. I have on occa...
by Chuck Morrison
Mon May 27, 2019 8:31 pm
Forum: Flat-Top Acoustic Guitars and Bass Guitars
Topic: Wrong radius dish for top-15ft What to do
Replies: 8
Views: 1953

Re: Wrong radius dish for top-15ft What to do

I've been using a 15' radius on my tops and backs for several years on both classical and acoustic steel string guitars. The arch goes from block to block with no flattening of the upper bout. I pre-arch double tops (classicals usually) to that 15' radius, which avoids the stress inherent in bending...
by Chuck Morrison
Wed Jan 09, 2019 7:23 pm
Forum: Archtop Guitars and Bass Guitars
Topic: Hybrid design question
Replies: 17
Views: 9773

Re: Hybrid design question

Hi Barry, Agreed. The electric strings were there because of my intent to add a pickup, which is still sitting in the shop. I was quite surprised how bright they sounded. Since phosphor bronze strings are pretty bright too, I didn't think it was an unfair comparison, but I agree it would be better w...