My mandolin, a resonator conversion

[eastmountain]

http://a2.sphotos.ak.fbcdn.net/hphotos-ak-ash2/38915_1407802799920_1377946907_1099612_1425811_n.j pg

I had a cheap asian mandolin that had a pretty lousy tone, when last year I got obsessed with resonator instruments. Since I didn't have a couple thousand dollars of disposible income to spend on a National, I decided to convert my mandolin to a resonator version.

I had a lot of fun with it, having to overcome many problems along the way. And the end result was rewarding. It looks cool and sounds much better than it used to. I have since added a hand rest over the biscuit bridge, but I haven't photographed it recently, so this is what it looked like when I first finished the re-build.

[Randi Gormley]

That's pretty neat. What does it sound like?

[eastmountain]

It is loud and surprisingly woody for a resonator. Not quite like a National RM1, but close.

[MikeEdgerton]

I love hotrods and this is a great example. Nice work.

[John Soper]

Cool conversion; makes me wonder about a similar project. Few questions:

-Solid wood or plywood mando to begin with?

-Did you use a new National resonator?

-Where did you get the coverplate? - looks great!

-Old Nationals have some type of dowel to stabilize neck to heel block- did you go with a similar construction, or trust that the rims, back and coverplate would stabilize the neck and prevent forward migration of the neck?

[eastmountain]

Definitely plywood. But I figured National built with plywood back in the '30s, so what did I have to lose?

The cone was actually a cheap asian guitar cone I had lying around. 9 1/2 inch.

The coverplate is actually part of a stovetop grill I bought at the thrift store for a couple bucks. I was trying to keep the build as cheap as possible. I really like the stovetop grills. I have since used them on two resolectric guitar builds as well. I have a stack of several in my shop for future projects. Every time I see them in the thrift store, I buy them.

I did put in a wood rod from the neck block to the heel block, but it didn't really stabilize things too well. When I tried to tune up, the body flexed and threatened to turn the body into kindling. I ended up using some metal stock I had lying around to connect the neck block to the coverplate and then a piece of wood under the tailpiece between the coverplate edge and the bend of the tailpiece. This transferred the string stress to the coverplate rather than the wood body, and since that coverplate is fairly thick metal (thicker than a standard coverplate) it held up nicely. Like I said, there were a lot of challenges to the build but that was half the fun.

[eastmountain]

Another challenge: I had to locate the cone centered on the body, so the scale was wrong on the neck. I pulled the frets and calculated the new fret locations, cut slots and reinstalled the old frets, and filled in the old slots with sawdust and superglue.

If I had it to do over, I'd have installed a new fretboard and used a 8.5" cone. The stovetop grill/coverplate wasn't much bigger than the 9.5" cone, so I had to devise brackets for it to screw into instead of screwing it straight into the wood.

[Jake Wildwood]

Mh, more web-based misinformation rearing up... most Nat'l necks and (wood) bodies were made by Regal or other Chicago makers... and weren't ply, though the inexpensive bodies were definitely boring wood like birch with painted "binding."

The only American maker to make extensive use of ply was Kay in the 50s and 60s, and sometimes the late 40s where you see it for figured-wood backs (veneer). They used it mostly on the back and sides, but not really the tops so much until the 50s and 60s.

[Ron McMillan]

I'm fascinated by this and would love to see a lot more photographs if you could post some with and without the coverplate in place?

ron

[eastmountain]

Hi Jake...I'm a big fan of your blog and website. You do phenomenal work.

As far as plywood Nationals go, I don't have personal experience, but Michael Messer's Notecannons site gives very detailed info on the early wood-bodied Nationals, including pages from Nationals own catalogs where they say they have plywood bodies. Did that mean the tops were solid and the back and sides ply? It is also my understanding that Dobro, when it split from National, built all plywood bodies.

[eastmountain]

I have photos of the build process at the resohangout website

http://www.resohangout.com/myhangout/photos2.asp?id=10677&photoID=14246&albumid=0

[bmac]

A very intersting and informative thread. Useful as I consider doing a similar type of conversion. Thanks especially for telling us of your errors as well as your successes.... It really looks great!

[MikeEdgerton]

I'm pretty sure Kay was using laminated wood in the late 30's. They were advertising it as a feature. There is some ad copy here someplace that talked about it. Also, L&H was making high end Washburn Guitars with laminated sides way back to keep them from cracking.

This (http://books.google.com/books?id=msEJ8cMqng4C&pg=RA3-PA1927&lpg=RA3-PA1927&dq=Kay+laminated+guitar&source=bl&ots=z7Ggv1t1O2&sig=VRdHCfxUPQOOwEUjVEU_WaRsmfU&hl=en&ei=FJByTYTwG4SKlwe2or1h&sa=X&oi=book_result&ct=result&resnum=3&ved=0CCgQ6AEwAg#v=onepage&q=Kay%20laminated%20guitar&f=false) wasn't what I was looking for but it talks about Kay.

[Ed Goist]

I'm pretty sure Kay was using laminated wood in the late 30's. They were advertising it as a feature. There is some ad copy here someplace that talked about it. Also, L&H was making high end Washburn Guitars with laminated sides way back to keep them from cracking.

I find it wonderfully ironic and humorous that plastic and laminated wood were featured in the marketing plans for musical instruments in the 1930s just because they were new technologies. Hysterical.

[hank]

Does it really matter what the rims are made of? Are the rims considered a resonate part of the body. Super cool conversion East mountain, can you post some sound clips? It's gotta smoke with a grill cover on it.:)

[hank]

After thinking about it for a moment I guess the rims are pretty important in transmitting vibration between the top and bottom.

[Steve Sorensen]

Neat project. Got me thinkin' . . .
Steve

[Ed Goist]

Very cool, eastmountain. Very Cool!

[Grommet]

Love it Eastmountain! There'd be so little wood in the top that ply probably makes more sense. Holds screws way better too. I know I prefer the wood/ply bodied resos to the full metal jacket type...mucho melllow. Topher Gayle's Mandonator 4 string model really lights my fire. Would love to here yours.

Scott

[Chief]

I love it also. Low tech, but very cool. I thought that cover plate looked familiar. It really works. I've seriously been getting into resonators lately, but don't have the skills to do what you did, so I have to buy mine ready made. Good job!

[Ben Milne]

I like, I like. It looks the goods.

What is the new scale?

[eastmountain]

15 inch.

[Jake Wildwood]

That thing's darn cool!

[Topher Gayle]

That's really cool! The coverplate is striking. Teflon coated, I think? for reduced pick wear!

[eastmountain]

Teflon, indeed, but it can be fairly easily sanded off for a metal look or paint job. I haven't tried to paint Teflon, but my guess is that doesn't work too well. Hmmm, wonder if primer would stick to Teflon?

[Dobe]

Curious, about the scale /re-fretting. Couldn't you have re-located the entire fingerboard & re-rigged the nut placement (up / down) easier than re-fretting ? Obviously the cone didn't have much 'BOZO" factor in the way of movement. Also curious ; any sort of a cone well / ledge? Nice project BTW !!!
I tried something similar with a 2-point Gibson (collapsed top) and a single Tri-cone some time ago. Wouldn't hold up under tension, ended up being a reso-uke. Finally re-topped the mando down the line. Fun project though; live & learn !
:popcorn:

[Denny Gies]

The definition of ambition.

[eastmountain]

Curious, about the scale /re-fretting. Couldn't you have re-located the entire fingerboard & re-rigged the nut placement (up / down) easier than re-fretting ? Obviously the cone didn't have much 'BOZO" factor in the way of movement. Also curious ; any sort of a cone well / ledge? Nice project BTW !!!
I tried something similar with a 2-point Gibson (collapsed top) and a single Tri-cone some time ago. Wouldn't hold up under tension, ended up being a reso-uke. Finally re-topped the mando down the line. Fun project though; live & learn !
:popcorn:

I built a plywood ring that sat on little dowel legs, glued to the back. There was so little top that I figured a well/ledge would destroy what little top was left. And in hindsight, I would had taken the fretboard off and relocated it, but I don't think moving the nut an inch down the neck was do-able. Perhaps making a new first and possibly second fret might have been easier than refretting the whole neck, but I still would have had to move the fret markers, and getting the fretboard off was problematic, so I opted for cutting new frets instead.

[Ben Stroupe]

thats sweet!