Search found 383 matches

by johnparchem
Wed Oct 17, 2018 4:45 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: 3 piece pernambuco back
Replies: 6
Views: 228

Re: 3 piece pernambuco back

John, I am assuming you're going for a live back because you're computing a target panel thickness. Check what the back panel mass will turn out to be and then compare that with other live back guitars you have made. I'm suspecting that the pernambuco might be too dense and therefore have too low a...
by johnparchem
Sat Oct 13, 2018 9:34 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: 3 piece pernambuco back
Replies: 6
Views: 228

Re: 3 piece pernambuco back

Thanks Simon, those posts were really helpful as I like the way Jim laid out the three piece back.
by johnparchem
Fri Oct 12, 2018 3:53 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: 3 piece pernambuco back
Replies: 6
Views: 228

3 piece pernambuco back

I am making a new classical guitar with pernambuco sent to me by my client. I have never used it before. I need to make a three piece back as you can see in the picture. pernambuco.jpg I tap tested the wood as I was getting very clean tap tones. I have not tried it on this narrow of a piece. I could...
by johnparchem
Wed Oct 03, 2018 1:32 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Three Random Questions
Replies: 3
Views: 136

Re: Three Random Questions

I built a falcate braced 14 fret to the body Martinish 00 on commission. The owner loves the sound and has recently bought a falcate brace classical guitar of mine as well. I like the the deep or more full bass sounds that I get from 12 fret joins. I tried to talk him into the 12 fret but all of his...
by johnparchem
Mon Aug 27, 2018 3:38 am
Forum: Instrument Builders Forum
Topic: 8 String bocote falcate braced nylon string crossover guitar
Replies: 11
Views: 1102

Re: 8 String bocote falcate braced nylon string crossover guitar

John, That looks great! How were you able to drop the main air that low? I'm primarily building with a Hauser plantilla and my air resonance is usually around 102 HZ and I would like to drop it some. Looking at Trevor's sensitivity analysis it looks like sound hole diameter and back stiffness are m...
by johnparchem
Fri Jul 06, 2018 8:05 am
Forum: Instrument Builders Forum
Topic: 8 String bocote falcate braced nylon string crossover guitar
Replies: 11
Views: 1102

Re: 8 String bocote falcate braced nylon string crossover guitar

As always nice looking work John. As always I am interested in the falcate bracing. You presumably beefed it up a bit for the extra strings so I wonder what height you ended up with? I wonder if you have had time yet to look at resonant frequencies, and perhaps particularly with this one, the bridg...
by johnparchem
Fri Jul 06, 2018 6:35 am
Forum: Instrument Builders Forum
Topic: 8 String bocote falcate braced nylon string crossover guitar
Replies: 11
Views: 1102

Re: 8 String bocote falcate braced nylon string crossover guitar

Thanks Mark, The neck wood is mahogany, I think the light hit it funny in the picture. I build for a customer, but take no deposits. My thoughts are I will try and if I succeed and they still like it they can buy it. If not well it was just like a private build. It has been awhile but she is all str...
by johnparchem
Sun Jun 03, 2018 6:05 am
Forum: Instrument Builders Forum
Topic: 8 String bocote falcate braced nylon string crossover guitar
Replies: 11
Views: 1102

8 String bocote falcate braced nylon string crossover guitar

I am ready to start cleanup and finish prep on this Bocote\Lutz spruce 8 string crossover commision. The 2 extra strings will be bass strings. I will have to play to see how low to go. The player would like to go down in fourths from the low E. I know I can make the 7th string a D and the 8 string a...
by johnparchem
Fri May 04, 2018 6:23 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Measuring top and back frequencies while voicing
Replies: 21
Views: 7723

Re: Measuring top and back frequencies while voicing

I am not sure it is Q, but when I took a voicing class from Jeffery Elliott a Portland Oregon classical guitar builder, he taught that he consistently thicknesses all of his top spruce panels for evaluation. Then on tapping he wanted to hear it ring for 5 seconds. It seems like the sustain would be ...
by johnparchem
Sun Apr 15, 2018 3:31 am
Forum: Instrument Builders Forum
Topic: Australian Guitar Making School - Students blog
Replies: 4
Views: 886

Re: Australian Guitar Making School - Students blog

Nice work on this guitar. It was interesting to see it built on a work board instead of an outside mold.
by johnparchem
Wed Feb 07, 2018 11:44 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: falcate Failure with an unexpected result
Replies: 22
Views: 8179

Re: falcate Failure with an unexpected result

I was feeling groovy, All and all it was a easier process. When I carved away parts of the braces I found no gap between the brace and the CF or the CF and the top.
by johnparchem
Sun Feb 04, 2018 8:24 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: falcate Failure with an unexpected result
Replies: 22
Views: 8179

Re: falcate Failure with an unexpected result

On my latest guitar I am slotting the bottom of the falcate braces for the carbon fiber. It really made the glue up process go a lot better for me. At the Guild of American Luthier auction I bought a router base\table called the Otter by the maker of Luthiers friend. http://www.luthiersfriend.com/aO...
by johnparchem
Sat Jan 27, 2018 8:04 am
Forum: Instrument Builders Forum
Topic: Audio comparison of 2 falcate SS and an X brace all mine.
Replies: 1
Views: 549

Re: Audio comparison of 2 falcate SS and an X brace all mine.

Too much room noise

I tried again this time with the mic a AKG C1000S, about 250 mm away pointing at the 12th fret

https://soundcloud.com/johnparchem/gore ... take-two-3

here is the Martin 00 sized falcate through the K&K pickup.

https://soundcloud.com/johnparchem/kandk-pickup
by johnparchem
Wed Jan 24, 2018 12:30 pm
Forum: Instrument Builders Forum
Topic: Mask the bridge glueing area
Replies: 11
Views: 1564

Re: Mask the bridge glueing area

I have been go back and forth between no masking and masking most of the bridge area and clearing to a scribed cut. Of those two options I am leaning toward mask most and cut to the line. My experience: If you mask inside 2-3 mm and after finishing you scribe the bridge outline with a sharp scalpel,...
by johnparchem
Sat Jan 20, 2018 7:52 am
Forum: Instrument Builders Forum
Topic: Audio comparison of 2 falcate SS and an X brace all mine.
Replies: 1
Views: 549

Audio comparison of 2 falcate SS and an X brace all mine.

I am about ready to ship my latest Falcate braced steel string so I thought it worthwhile to record the difference between the two falcate SS guitars that I still have: My WRC\Cocobolo Martin sized 00 and my Spruce\Koa Gore medium sized SS guitar. As an additional bonus I recorded the same tune on a...
by johnparchem
Fri Jan 19, 2018 10:48 am
Forum: Instrument Builders Forum
Topic: Cocobolo\WRC Falcate 00 12 fret to the body
Replies: 19
Views: 5815

Re: Cocobolo\WRC Falcate 00 12 fret to the body

Whoops forgot to post the final spectrum graph. Everything is not exactly where I had hoped but the guitar sounds great, my target T(1,1)2 was 180 Hz and I am at 181-182 Hz with no mass. Also nothing is right on a note (but the air is close). The back is not super responsive but it does couple. I go...
by johnparchem
Fri Jan 05, 2018 2:52 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: 1st box closed - spectrograph result
Replies: 2
Views: 760

Re: 1st box closed - spectrograph result

I am still a novice looking at these but here are my thoughts. If I look at the red it looks like your top and back are pitched close together with that double peak. If the peak around 220 Hz is the top resonance, it will move away from the back when the bridge is glued on; a good thing. If the back...
by johnparchem
Mon Jan 01, 2018 12:27 pm
Forum: Instrument Builders Forum
Topic: Cocobolo\WRC Falcate 00 12 fret to the body
Replies: 19
Views: 5815

Re: Cocobolo\WRC Falcate 00 12 fret to the body

I finished this guitar. Falcate braced western red cedar top Cocobolo back and sides Australian blackwood bindings Brazilian Rosewood bridge and headstock veneer Post Catalyzed Royal Lac finish http://www.harvestmoonguitars.com/falcate00_12fret/fallcate00%20(468).jpg http://www.harvestmoonguitars.co...
by johnparchem
Sat Dec 09, 2017 2:35 pm
Forum: Instrument Builders Forum
Topic: 75 walk throughs, no more till next year :(
Replies: 9
Views: 1334

Re: 75 walk throughs, no more till next year :(

Thank you for all of these walk throughs!
by johnparchem
Fri Dec 01, 2017 12:51 pm
Forum: Instrument Builders Forum
Topic: Cocobolo\WRC Falcate 00 12 fret to the body
Replies: 19
Views: 5815

Re: Cocobolo\WRC Falcate 00 12 fret to the body

Thanks! I made some progress. Since the last post I sprayed the guitar with post catalyzed Royal Lac a hardened shellac product. While the finish was curing I laid up a Brazilian Rosewood bridge blank with two sheets of 5.7 OK 3k plain weave carbon fiber sheet. While I was at it a laid up a blank fo...
by johnparchem
Tue Nov 14, 2017 5:48 am
Forum: Instrument Builders Forum
Topic: osage orange
Replies: 4
Views: 1113

osage orange

I am planning a classical guitar using a US wood Osage Orange for the back and side at the request of a client. I found a set that is pretty well quarter sawn (I suspect the trees are not wide enough to be perfect across the width). The wood is very dense and stiff, some compare it to BRW but I am f...
by johnparchem
Thu Nov 09, 2017 10:36 am
Forum: Instrument Builders Forum
Topic: Cocobolo\WRC Falcate 00 12 fret to the body
Replies: 19
Views: 5815

Re: Cocobolo\WRC Falcate 00 12 fret to the body

Thanks ernie! I finished the pore fill with zpoxy and the grain really pops. I will seal the zpoxy was a few wash coats of shellac and ultimately spray post catalyzed Royal Lac. http://harvestmoonguitars.com/falcate00_12fret/fallcate00%20(358).jpg http://harvestmoonguitars.com/falcate00_12fret/fallc...
by johnparchem
Mon Nov 06, 2017 4:29 pm
Forum: Instrument Builders Forum
Topic: Cocobolo\WRC Falcate 00 12 fret to the body
Replies: 19
Views: 5815

Re: Cocobolo\WRC Falcate 00 12 fret to the body

RIght before I left on a one month road trip I decided I needed to make a new neck. Using a chisel I tore out part of the heel on the side of the neck that runs along the cutaway join. The neck I made will be easy to convert to a more classical heel on a future guitar. Making the neck mostly was don...
by johnparchem
Sat Oct 07, 2017 12:11 am
Forum: Instrument Builders Forum
Topic: Cocobolo\WRC Falcate 00 12 fret to the body
Replies: 19
Views: 5815

Re: Cocobolo\WRC Falcate 00 12 fret to the body

Moving on to the neck ... When I build my last guitar I had a neck roughed in with with the tenon and brass inserts installed. I did not use it as I wanted a higher heel for a tradition classical heel. It was cut just right for my cutaway heels. So I got a head start. I have found it a pain to taper...
by johnparchem
Mon Oct 02, 2017 12:50 am
Forum: Instrument Builders Forum
Topic: Cocobolo\WRC Falcate 00 12 fret to the body
Replies: 19
Views: 5815

Re: Cocobolo\WRC Falcate 00 12 fret to the body

whoops binding is Australian Blackwood not African.