Resonator guitar

[Robin Fawell]

I want to build a steel or german silver bodied resonator guitar using the methods outlined by Mike Dotson, Chris Paulick and Clay Jones a few years ago in the MIMF forum.

My guess is that steel will cost less than German Silver. However GS is softer and easier to work.

I want, ideally, to mo(u)ld /curve the back as described by Chris Paulick. Is this feasible with Steel?

I will appreciate any advice from the forum members.

Robin

[Jeremy Elliott]

That's a great tutorial, isn't it? I think it should be possible with steel, though I haven't done that specifically.

[Freeman Keller]

Robin, while I have not built a metal bodied reso, I happen to work in a metal fabricating shop and know a little about the materials and techniques. I also own three resonators, a brass bodied biscuit, a wooden spider and a home made koa tricone.

First, a couple of comments about materials. Brass and steel have different sounds - if you go to the NRP page there are sound clips of both. Wood obviously has a different sound from either of them. Both brass and steel (I assume you would use mild steel and plate it however you could even use stainless) can be cut with a laser cutter (which is what my shop uses) or a band saw. Brass can be cut with shears, very thin mild steel also, but it tends to bend the edge. Brass must be brazed (so called "silver solder"), mild steel can be brazed or welded, stainless must be TIG welded. With the very good wire feed and TIG welders availabe today I would definitely use one of them on mild steel.

Both brass and steel can be worked into complex shapes - large shops like NRP use big presses, you can use techiques like an English Wheel (find a hot rod or custom motor cycle builder). Brass can be hand hammered over a a buck, steel also if the gauge is thin enough and the bends aren't too radical. As they say, practice on scrap.

If you use the Autocad drawing of the Tricone that is floating around the web be aware that it does have some dimentional inaccuracies, however it does make a good starting point. If you want to build a single cone biscuit you will have to work up your own plans - with a resonator all the measurements start at the bridge and work out.

Here is a thread about my home made woodie - it might give you a few ideas. Also, when I first got the idea for this I had actually considered making one out of Titanium following the MIMF archives - (would you call that a TiCone?). Ti is pretty expensive - I figure it would have cost over a grand just for the materials, and would have required special TIG welding, but one of my buddies works for Moots Cycles and agreed to do that for me. There is also a guy building aluminum bodied resonators - I could send you a link. Here is mine

http://bigroadblues.com/forum/viewtopic.php?f=4&t=11037

Good luck with yours, let me know if I can help with any of this.

[Robin Fawell]

Thanks for the comments. I've managed to avoid building the metalwork. There is a company here in the UK importing resonator guitars. They have offered me a guitar with a badly fretted neck at a reduced price. This means that I only need to build the neck.

I am under the impression that resonator guitars have fretboards with bindings. Is this deliberate?

Will this prevent an angled metal or glass slide from striking the edges of the frets?

Any comments will be appreciated.


Regards Robin

[Michael Lewis]

Is this guitar to be played with a steel or fingers? Only fingers need frets.

[Freeman Keller]

Thanks for the comments. I've managed to avoid building the metalwork. There is a company here in the UK importing resonator guitars. They have offered me a guitar with a badly fretted neck at a reduced price. This means that I only need to build the neck.

I am under the impression that resonator guitars have fretboards with bindings. Is this deliberate?

Will this prevent an angled metal or glass slide from striking the edges of the frets?


Regards Robin

Robin, a couple of thoughts. I am a part time reso player - both lap and Spanish style, and as Michael say, if it is going to be played strictly lap style you need fret markers but not actual frets. However I am guessing that you want to play Spanish or your questions would be about square necks (and while there were some square neck National metal bodied tricones most are roundies).

Most resonators have what is called a neck stick - the neck extends through the body rather that terminating at a neck block. There are some little wooden mushroom looking things or some other sort of shim that sets the neck angle, which in turn sets the action. I have seen a source for ready made reso replacement necks if you want to buy one rather than build it. I have a couple of pictures of the insides of my metal Duolian that show the neck stick if you would like them.

Traditionally resonators have 25 inch scale lengths - it will be very important to get the neck and fretboard exactly the right length since the bridge position will be fixed. Depending on the style of play you may want wider or narrower neck and more or less radius. Some modern resos (and many of the PacRim imports) have 16 or so inches of radius and 1-11/16 nuts - these appeal to people who will play mostly fretted (I have one on the Duolian and I don't like it). More traditional necks are 20 inch to dead flat and 1-3/4 to 1-7/8 at the nut - slide players will prefer that. Most narrow necks are paddle heads, most wide ones are slots, but that does vary a bit. Also, most resos are 12 frets clear, but there are some that have the body pushed down to the 14th.

As far as binding - I think it is purely cosmetic. My 1932 Dobro has white plastic binding on the neck (but not the body, it was the cheapest model). My 1980 Duolian has an unbound rosewood board, and my home made tricone and Weissenborn are bound. With a bound neck the ends of the frets extend over the binding. Most Spanish style slide players mix fretted notes in - with good technique you shouldn't be hitting the edge of the board with your slide (lap players seem to do it a fair amount).

[Robin Fawell]

Thanks Freeman and Michael

I want to play "Spanish" (Frets) and slide a la Robert Johnson. The guitar I have bought is a Nickel plated bodied Single Cone, 12 Fret, MM Lightning see http://www.buskerguitars.co.uk/5.html. This is imported from China.

I have removed the coverplate and cone and removed the neck and neck stick. I am aware of scale length and intonation aspect.

I may be wrong but it looks as if the existing neck stick is butt jointed with epoxy adhesive to a spigot extension of the heel. For the new neck I'm thinking of sandwiching the neck stick, top and bottom and side to side with the heel and neck wood components. You could call it a "through neck stick". I would use mahogany for the neck, heel and neck stick. The neck stick would be part of the heel.

To stay out of trouble I would assemble the neck and heel to the guitar to ensure a good heel fit and get the neck angle correct and then remove the neck to fit the fretboard. I am also thinking of sandwiching carbon fibre rods/tubes into the neck stick for extra strength.

Your comments regarding the neck width are very apposite. I have never played slide guitar. I play an acoustic guitar (Takamine). This has a 1 7/8" neck. The neck I have removed is 1/16" less than that of the Takamine.

I am inclined to use 1 7/8" for the neck width. The fretboard radius is smaller on the Takamine than the National replica. Obviously it will be more difficult to make slide contact on more strings simultaneously with a radiused fretboard and therefore my inclination is to copy the National, flatter type.

This is all new ground for me I have never played slide before.

I have also received some advice from the MM Lightning designer/importer/ slide guru Michael Messer who agrees with your comments re fretboard binding. ie that it is cosmetic. I will therefore use a non bound fretboard either ebony or cocobolo.

You may be interested in Michael Messer's website. http://michaelmesser.proboards.com/index.cgi

Thanks for you comments. Robin

PS I am very impressed with your koa dobro! Good Work.

[Freeman Keller]

I'd say that you've got things pretty well covered. Resonators are a little different inside and out - just wanted to make sure there were no surprises. Personally I find that about 20 inch fretboard radius and at least 1-3/4 at the nut work for my mixed style of fretted and slide - as you say Robert Johnson mixes it up in his playing (ironically RJ never played a reso but his songs sound good on one). I set my action just a hair higher than an acoustic but not so high that its hard to fret. You'll learn that clean slide work is mostly technique - people play slide on low action electrics with slinky strings.

While you have it apart you might consider a cone upgrade - one test of the quality of the cone is to tap it with your finger - the more it rings the better. I've heard some stamped cones that just make kind of a dull thud. Continential, Beard and NRP make good spun replacements - I run a NRP "hot rod" in both the Duolian and the Tricone. Some other little setup tricks - put a piece of leather or foam rubber under the tail piece to keep it from rattling on the top. Fretted intonation will be terrible - there is no compensation. You can cheat a little and make the break point of the saddle near the back. There shoulde be two (maybe four) screws under dots on the fretboard extension - that holds it down and is part of the neck angle adjustment.

Here are two pictures of mine with the cover off - the neck stick and mushrooms (and a dust bunny)



and the NRP cone (and carbon fiber biscuit, something they didn't have in 1930)



Good luck, I'd like to see some pictures when you get it apart and back together.

[Eddie McRae]

I build a line of wood-bodied resonators that I designed using National's Triolian as basis. Had my fair share of problems with the first one so here's a little more info concerning steel-body reso specs:

1) National's blueprint stated a .5 degree neck angle with a cone depth of 1". I found on the first one that I built that this didn't work. At a comfortable action height, these specs placed the strings to close to the coverplate and there was hardly no break angle at all from the saddle to the tailpiece. I wound up having to recess the coverplate down into the top to compensate but that still didn't eliminate the break angle issue. I have since modified my design and now use 1.5 degree neck angle with 7/8" cone depth. And I construct a shim under the fretboard extension to fill the gap created by the neck angle. I have pics if needed.

2) Standard fretboard dimensions on a 12 fret are 1 3/4" at the nut and 2 1/4" at the 12 fret/body join. Of course, these can be altered to your preference.

3) Regarding intonation....if you want a more accurate setup....I now wait and slot my biscuits once I've finished construction and have the cone in place. I use a tool similar to Stewmac's "Saddlematic" to mark an angled (intonated slot) in the biscuit and I also use a compensated bone saddle.

4) Regarding playing style... a radiused string profile lends itself to easier fingerstyle playing while a flatter profile makes slide playing easier. Regardless of fretboard radius, you can always flatten your string profile as needed to suit your style by simply filing the nut and saddle slots to set the strings at your desired height and profile.

5) One other thought worth mentioning since it was brought up above; I recently did some work on a customer's Regal metal-body. Neck was attached in the usual neck-stick fashion with an angle heel and four screws (located under the fretboard markers) holding the fingerboard down onto the top. The support pedestals were held in place by a drop of silicone glue under each pedestal base plus they had screws running down through the neckstick and into them.

Just my two cents here, but, after having worked on that metal-body and seeing it's construction, I think I might would eliminate the neckstick altogether and install an actual neck block and use a bolt-on butt-joint neck design to mount the neck. And then just provide support for the soundwell flange by constructing a few support pedestals. This is how I build my wood-bodied reso's and it works great.

[Mike Dotson]

Just one comment re. the neck stick or lack thereof. I also go without on wood body guitars (I bolt them on) but when putting together one of the Stew-Mac metal body kits (since discontinued) that didn't use them I discovered that while you don't need a neck stick, adding a couple 'mushroom' posts under the well made a huge difference in tone and particularly sustain. I think on metal bodies the back really needs to be damped and the top needs the support. Personally I'd just stick with the stick it's a simple and effective way to mount the neck.

[Eddie McRae]

I agree with Mike. If you chose to eliminate the neck stick, I'd definitely use a minimum of 4 if not 5 pedestals under the soundwell. I use 5 on my wood-body builds.

[Mike Dotson]

On the metal body I was taking about I only added two between the soundwell and the back. National at one time used four but eventually went to only two.
On my wood body guitars I don't use any but instead brace the back like an acoustic. It gives a little more 'modern' sound I think. My '33 El Ttovador uses two between the well and back.

[Robin Fawell]

Thanks to you all for your helpful comments.

To Freeman

While you have it apart you might consider a cone upgrade - one test of the quality of the cone is to tap it with your finger - the more it rings the better. I've heard some stamped cones that just make kind of a dull thud

Later on I will definitely take up your suggestion. I've tested the cone supplied with the guitar. I does ring a little but it is difficult for me to judge.

To Eddie and Mike

I wound up having to recess the coverplate down into the top to compensate but that still didn't eliminate the break angle issue. I have since modified my design and now use 1.5 degree neck angle with 7/8" cone depth.

I'm not sure what are the important issues are here. Is it the height of the saddle above the biscuit? Is it the angle between the string and the saddle? On the import neck, the neck is not at right angles to the fretboard and the fretboard thickness is thinner at the nut than that at the 12th fret.

I think that it may desirable to include the neckstick. I am concerned that there is some flexibility in the upper section of the body (between the F holes). This could alter the neck angle over time.

With the neck stick attached by screws at the top and bottom of the cone well and fretboard attached (in my case) with 6 screws through the metalwork to a plywood spacer. The whole front of the metal body is quite rigid.

Here are photos of the plywood spacer and the top of the guitar.

There is a gap between the plywood spacer and the neck stick. There was a small "wedge" placed in the gap.

[Robin Fawell]

Continued

To Eddie

I also use a compensated bone saddle.

Do you mean saddle or nut?

2) Standard fretboard dimensions on a 12 fret are 1 3/4" at the nut and 2 1/4" at the 12 fret/body join.

These are the same as the import neck.

[Mike Dotson]

The wedge is normal.

As far as setting the neck angle install the cone in the well and lay a straightedge on the frets.It should just clear top of the biscuit and that will give you anywhere between 3/16-1/4" of saddle height depending on how high you want the action.

[Eddie McRae]

In my case, on the first one that I built using the specs from the blueprint, the neck had only .5 degree back angle and the cone sat a little too low in the body. AND I was able to get a nice action height with no trouble UNTIL I put the coverplate on and realized that it sat too high and was making contact with the strings. That's why I have since changed the neck angle and cone depth. As for your question....I meant compensated bone saddle. Most all resonators usually have a wooden saddle, most commonly hard maple. But I do as much as I can when I build one to get as much sustain as possible out of it. The bone saddle helps with that. Also, with it being compensated, it helps to provide a more accurate intonation. BUT, as I said earlier, I also wait until I have the cone/biscuit installed before I mark the biscuit for the saddle slot. And I mark it at an intonated angle, the same as you would mark and slot an acoustic bridge. You most likely have a biscuit/saddle already so, at this point, I wouldn't worry with that. But later, if you find that you're not satisfied with your intonation, there is a solution.

[Robin Fawell]

Thanks again to Mike and Eddie. I have started to build the neck.

I will use the same scale length of 25.5". I will use 12.75" distance from nut to the 12th fret and add an extra 1/8" as compensation for string bend affects from the 12th fret to saddle..

I have a small laminate trimmer and will use it to build a plexiglass 20" radius template and 20" radius sanding mo(u)ld.

Robin

[Robin Fawell]

I have been thinking about how to ensure that the fretboard is angled correctly.

A small angled wedge made from the fretboard wood, trapped under the fretboard seems to be the most practical method. Obviously the heel will need angling first.

I know that one could have an angled fretboard. However if any alterations are needed the work to correct the fretboard would be greater.

It is possible that Mike was referring to this in his reply?

The wedge is normal.

When I referred previously to a "wedge" in the import guitar I was referring to a wooden shim 3/4" X 3/4" X 3/16" which fell out from inside the guitar. I do not know where it was located but I guess it was placed between the plywood spacer and the top of the neck stick. I showed a photo of the plywood spacer in an earlier post.

I have just received the blueprint showing the design from J Beard. This shows the guitar front attached with 3 screws through the fretboard. Two of the screws go through the fretboard brace on the dot holes between the 16th and 17th fret. The middle screw goes through the fretboard after the 19 th fret.

On the import guitar there are 6 screws. Two screws are located on the centre line at the 12th fret and between 16th and 17th fret. The remainder are at located about 3/4" form the centreline. Two between frets 15 and 16 and two between frets 18 and 19. All six screws sandwich the metal body to the fretboard but not to the neck stick.

I am proposing to replace the plywood spacer which is about 3/8" thick with a metal plate 1/16" thick. I would use machine screws for the four outer holes and two wood screws through the plate and into the neck stick on the centreline. The neck stick would be recessed to accommodate the plate.

The idea is to preserve,as much as possible, the beam height of the neck stick whilst stiffening the front upper central metal body. I appreciate that I will need to trim the neck stick for neck angle changes.

I hope that this message is not too confusing. Please let me have any comments or criticisms.


Best Regards Robin