Finally found a resonator to call my own… for a while.

[mannylopez]

I recently came across a great resonator and figured it was time to formally say hello to everyone here. I bought it without knowing anything much, it was dusty dirty and the case was in the WORST shape I've ever seen. I took a gamble on a guitar that could have ended up being just wall decor.

Fortunately, it turned out to just need some TLC to get it back in playing shape. I cleaned it immensely, soap and water was needed to get the cone gunk off and once taken apart, I began to look online for tips on reconditioning the guitar. My research indicates that it is likely a late 1930's Dobro Alumalite M47. It has some cosmetic issues, and I suspect could use a neck reset, but I decided to follow the information here and on Stew-Mac on how to get it into some sort of playing shape.

- The nut was okay, but the spider was backwards and it was strung left handed. I am surprised the nut was being used as it was.

- One tuning key took a hit at some point in the past 70+ years and its missing a tuning key button, and the shaft is slightly bent, but it does not affect functionality. I cast a roughed out button replacement from epoxy resin and mounted it until a suitable replacement can be made/sourced.

- There is some peeling of the pearly headstock veneer. It doesn't go very far in, just on the one corner, I would like to fix this but its likely not an easy fix.

- Ensured spider legs seated well, and sanded them flat using 320 grit on a glass surface. 

- The break angle is quite low at the bridge and I cannot really lower it anymore than it already is - it may already have killed the tone, But it appears very stock.


Which brings me to a few questions:

- There is a felt ring around the inside of the body that the resonator cone rests on. Is this common in these guitars or was this placed there by someone trying to silence it?

- This doesn't sound like other resonators I have heard. It has a projection but not that Tin Can sound I expected. Is this due to the model or that felt ring? I loaded the cone as suggested with a 1/4 turn on the screw, just enough to kill the buzz. Going a bit tighter didn't seem to change the sound much and was worried I could go too far. I have taken it apart, in wait for the answer to this - how does the M47 sound or how SHOULD it sound? 

- Last string set were 13's and I finger pick, so this set I grabbed 12's… From what I hear, there is a certain amount of tension needed to load the cone, and most of the guys use 16's or something like that… is that predominantly for slide playing or is it needed for proper cone loading?

I will try to post some photos later today, I've posted photos, but not mammy, as work commitments have come up and hindered my novella I started here. Until then, any help/comments would be appreciated. As Neil Young said… it's not his guitar to keep, and it's only here for a while. I hope the same for this Dobro. 

Attachments:

[alexandre]

I have a Dobro M-32 (steel body), with the same "lug cone + long-legged spider bridge", but without any felt ring...

It sounds already good like that, so that I don't plan to change anything, even if I've found a short-legged spider to fit that lug cone.



You can fit it with 12's without problem, if you prefer... These are lovely guitars & they do sound great in picking style with standard tuning:

[alexandre]

By the way, my exemplar have a "non-offset" bridge and is from 1937:

[Deleted]

Very nice.
Are you sure you've got the offset spider the right way round?
On both of my metal dobros, the offset is 180 degrees the other way.
One of mine is brass the other is steel. The lumalite apparently sounds very 'sweet', and will sound even sweeter with the lug cone. If you like it, fair enough, but its probably not a chunky enough sound for me.
TT

[mannylopez]

Thanks for the comments.

Alexandre - That first video is a beauty. What tuning is it in? As well, what is the song? I see in your photo of the spider that the spider legs do not sit over the dimpled part of the cone. Is that how it should be rotated or does it matter? Mine doesn't have the same sound as yours… I am wondering if the felt ring is not original and should be removed.

Deuce - I am pretty sure it is the right way around now as it is. The scale is 24.5" based on my nut to 12th measurements, and the saddle sites about 24.75" this way as opposed to 25.25 should it be reversed. It was 180 when I got it as it was strung lefty and guess that is why it wasn't played much. Probably didn't intonate so they put it to the curb. What is a lug cone?

Hopefully I can find out about that felt ring. I suspect my concerns lie there. I won't put the new strings on until I figure out whether or not I need it there.

[Deleted]

OK. I came across another person a while back with the offset as yours is and they said it was OK too.
There was a recent long discussion on felt gaskets a couple of weeks ago, if you can find it. I think it might take any excessive metallic overtones from the metal dobro sound. If it was put in by the manufacturer, probably best leave it. Removing it could make it sound a lot worse, and it would be quite difficult to undo.
Leave it in I reckon.
As for the lug cone, the idea was to reduce the amount of metal used for the spider. By stamping the ledges in the cone, a shorter spider could be used. Using a normal spider as alexandre is doesn't really affect it.
I had a lug cone once but IMO it lacked some bass, so I replaced it. Some people love them though.
TT

[rbe]

I would definitely keep the lugged cone. A regular profile spun cone will not fit with the full length neckstick in a fiddle-edge. And, you do have the spider offset correct. The Lumalite will not get the sound you would expect from something like a single cone National. It is very sweet and balanced. Hopefully not a tin can sound. If it was mine, I would take the felt ring out. I think the overtones the felt possibly reduces help to give the Lumalite a more complex sound. That makes up for it not being bassy. But that is a personal preference. Not everyone will agree.

You are in the delicate zone with this guitar. The aluminum body is not stiff and neither is the fiddle-edge construction. The geometry on these guitars gets very out of whack over time and most likely yours needs to be addressed. It all starts with proper body geometry and a straight neck. From there, a neck set can be done and the break angle addressed. From my experience, not many luthiers know their way around one of these guitars, so proceed with caution. Your guitar looks like it has most of it's finish. That is good. And it looks like it really hasn't been messed with. That is good, too. If it gets set up properly, it will be a very nice instrument. At this point, you don't want to do anything to it that can't be undone.

Hey Duece, I think the lugged cone was a clearance thing. The spider sits lower. so the coverplate clearance is greater. The thickness of the plywood top is not the same on all Dobros. Being able to set the spider lower by placing the short legs on the luggs made up for the thinner top. Also, I think I read somewhere that not all of the Dobro coverplate variations have the same arch.

[Matt]

Oh man i love these fiddle-edged Dobros...ever since I played one in No Tom Guitars. If i ever buy a real National/Dobro, it may well have to be one of these...

[mannylopez]

I get the lugs now... I guess it doesn't matter where the legs on this spider sit in relation to the lugs, correct?

I am torn on keeping the felt ring. Scared to remove it, but equally curious. The sound is very reserved but when chording on the first three frets, it sounds quite nice and mellow. Not very resonator like. Maybe I will try to make a video. Though I am Terrible at playing it. Thinking that felt ring is the component that has the biggest effect on the type of tone it has. Just not sure if it's factory or not. Has anyone seen one like this from the factory?

Thanks for the comments. The finish is all pretty well there, except for the part where the old pick guard off gassed and bubbled the paint some. Close up, there is some great checking in the paint etc. beauty to look at. I would like to make a new pickguard, but I haven't a reference piece to create it from. It would hide the Freddy Kreuger patches of paint tho. There's a shop that could do a neck reset, but given the cost of that, It could be a long time away so I will play it as is before anything drastic is done.

[alexandre]

If I were you, I wouldn't take off the felt before you can test the guitar with a right neck reset...
... so that you can test & hear this instrument in the best possible conditions. After that, you could tell if its sounds OK for you or not.

As rbe suggested it, don't give that job to the first luthier, just because resonators are NOT common guitars, and most of the luthiers don't know how a resonator can sound at his best.
Even a great guitar luthier could damage your instrument, or the cone, and believe me, these are rare to find in such a good shape, and nobody could get you one as spare !
If you're in Europe, Mike Lewis is the one you need (he has done a real fine neck reset & refret of my 1930 National Triolian), and I guess that rbe could tell you more if you're in the USA...


Concerning the lug vs normal cone differences, pictures can explain better than words:

Here's what a lug cone should be (I mean fitted with short-legged spider bridge):


Here's a "normal" Dobro cone:

[rbe]

Sorry, I have to correct myself. It is not the neck-stick that is the problem with spun cones in fiddle-edges. It is the second shelf for the optional biscuit cone set up. The bowl of the cone comes in contact with the edge of the well and kills the cone's ability to vibrate. The stamped cone has a straighter bowl and clears that edge. So you only find the stamped cones (so far I have only seen lugged ones) in fiddle-edges. Also, I think that whether they had a short leg or long leg spider was more a matter of what was in the parts bin. I do think that you more commonly find short leg spiders and stamped cones in Regal built Dobros. A majority of the fiddle-edges were built by Regal. So those spiders found their way into fiddle-edges, I don't think they really need them.

As far as setting up your guitar. Here is the problem. Body geometry is first. That has to be right before you set the neck. If you set the neck first, and then go to get the body right, the neck will end up with too much angle. This is all most important on Lumalites, because they tend to have the most distorted bodies.

Did you take the cone out? I am curious if you did, what you saw supporting the neck-stick? I have seen four variations. One small mushroom pad at the neck end of the well. One very large pad in the center of the stick. One massive structure, that along with the neck-stick, supported the well in four places. This one also had a wood ring that was under the well where the spider cone sits and is held in place with many screws (a good reason for felt in the well, to eliminate rattles). Last was no support at all. That was just from someone who was clueless and not original. The massive one was on a Lumalite with a similar headstock profile to yours. So I wonder if yours is like that too.

[Michael Messer]

Hi all,

My apologies for not joining this interesting discussion, but I have been very busy this week.

Be careful of your aluminium Lumalite Dobro, it is a fragile guitar and rbe is correct that over time the geometry of these can be all over the place. They are beautiful sounding sweet guitars, but they are not loud and they are not Nationals!

Be careful about the felt gasket. In regular fiddle-edge Dobros there is no way that felt improves anything, but I have noticed in the few Lumalites that I have seen that the felt gasket (factory fitted) did sweeten the tone. A friend of mine had a beautiful sounding one that was in desperate need of restoration, but after its restoration it had lost all its character. It played perfectly, but it lost all its wonderfulness. This was due to the subtlety of these guitars - there is a very fine balance and they are fragile.

rbe - that is correct about the arch (shape) of Dobro coverplate variations. I think it was Mike Lewis who told me about this.

Gotta go....

As they say in Slovakia (land of the Dopyeras) "Dobro....DOBROO.......DOBROOOOO"

Shine On
Michael

[rbe]

Found this photo I took of the inside of the fiddle-edge I mentioned. It shows the massive, internal, wooden structure. It also shows evidence of the felt that was glued to the well, over the screw heads. What was amazing about this contraption is that it was very roughly made and looked as though they were just winging it. The icing on the cake was the use of thick, soft cardboard to line the back side between this wooden "canoe" and the body. It had to be a total tone killer. I have never seen another one like this. I know that Don Young had one with the same headstock profile and it had the wooden ring screwed to the well, but none of the other supports remained. Based on how much I like the sound of my Lumalite with the smallest internal supports, I just think all of this stuff has to go. But, I do not recall what I did inside this guitar, I think I tried to just make the supports less massive and minimize the amount of wood needed to give the same support. I do think they were finding out that the aluminum was not rigid enough for this type of body construction and they were trying to figure out how to shore it up. Another thing, over the years, after the wood shrank a bit, this became a big somewhat loose mess.

[alexandre]

Here are photos of the inside of a steel body fiddle-edge, for comparison:

[rbe]

That is the very large pad that I mentioned. My preferred setup is the small pad under the stick where the shim is at the neck end. I usually add another at the other end of the stick too. Much like it is done in a National.