Restoring Djembe Questions Photos - Soundhole etc.

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Restoring Djembe Questions Photos - Soundhole etc.

Postby batadunbata » Thu Aug 03, 2017 9:33 pm

Hi,
I bought a charming hand-carved Djembe on Craigslist (see photo, it was cheap ($75) because it had a busted skin, but it turns out to need more than a skin. I suspect it's made of Dugura, because of the color and grain, and it's very hard, and heavy despite being thin-walled. It rings nicely when struck.
I have questions about repairing the soundhole.

First I cleaned it with a magic eraser sponge (2 photos attached), which removed years of grime and dirt. I plan to give it a light sanding with fine paper and lightly coat with clear rosin varnish.

I also plan to repair the rim (photo in my reply below - max allowed per post is 3 photos) by filling in a few minor flaws with gum rosin, sanding down the three highee areas, and rounding the edge since it's a bit flat on top.

My question is about repairing the sound hole (photos in replies below):
There are two sections on one side which seems to have been chopped out quickly, possibly to open it up. The hole is a bit rough on the other side as well.
Would it be advisable to fill in the missing chunk, and sand down to a smooth finish?

The other issue is caused by the fact that the bowl is not perfectly centered on the stem, causing the soundhole transition into the stem to be uneven. One side it's straight drop, whereas on the other side, there's an overhang. Photo in my second reply.

Are these serious issues, and if so, can they be worked on? And if so, is it worth it?
It's a thin walled 11.5" x 23", so it weights 13lbs, vs 20lbs on my 12.5"x24" regular walled Dugura, so it's portable, but a bit on the smaller side.
It's querky with the offcenter bowl and long stem, and roughness issues.
What do you think?

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The Drum
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Before and After cleaning
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After cleaning Dry, Wet and Before cleaning
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Last edited by batadunbata on Thu Aug 03, 2017 9:53 pm, edited 1 time in total.
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby batadunbata » Thu Aug 03, 2017 9:39 pm

Photos of bowl and soundhole: (stem tunnel photos in next reply)

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Bowl from above - also shows rim
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Soundhole with chunks remove
visible
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Soundhole on other side - shows roughness
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby batadunbata » Thu Aug 03, 2017 9:47 pm

Photos of stem tunnel: (first one attempts to reveal the overhang I mentioned, but it's hard to see clearly, other two show tunnel from below, which reveal uneven rough soundhole shape)

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Attempt to show stem overhang - using camera flash
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Stem tunnel and soundhole from below
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Soundhole viewed from below closeup
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby drtom » Fri Aug 04, 2017 5:06 am

If the rope and rings are drum worthy, that's a good buy. Do a good job and you'll have a fine djembe.

Level, shape and sand the bearing edge if it needs it. While it probably won't hurt to do any of the work you suggest to the trumpet, I doubt you're going to hear a difference.
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby djembefeeling » Fri Aug 04, 2017 7:00 am

I second that. Don't worry about anything but the bearing edge. From your first photo it seems there are two cracks and some rough places that'll need some fixes and sanding.
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby michi » Fri Aug 04, 2017 10:21 am

My take, too. Fiddling with the hole in the waist won't change the sound one iota.

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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby batadunbata » Sat Aug 05, 2017 12:24 am

Wow, that's great news that it's unnecessary to rework the soundhole, thanks so much Djembefeeling, DrTom and Michi.
I could hardly ignore it from any one of you, let alone all three in agreement.
And I'm hardly disappointed that I don't have to embark on a job like that! Whew!

I'll do as you suggested, fill and sand the bearing edge and forget about the sound hole.
Thanks DrTom, I hoped it was a good shell for the price but wasn't sure. It does have a 4" crack that's been filled, and a smaller one, but the rim rings when struck despite that.
The rings seem good, hammer welded (burn mark on shell), although I haven't seen what they're like under the fabric (could be rusted).
The rope is good, but I want to swap it out for something less slick/techno looking, since the shell is very rustic, with a chiseled surface, it's a mismatch.
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby djembefeeling » Sat Aug 05, 2017 8:12 am

About that crack (on the pic it looks like there are two of them running from the bearing edge into the bowl) I have learned to drill a hole right into the bearing edge from above where the crack starts and fill it with a wooden dowel. It's supposed to stop the crack from growing, and the wood might crack everywhere, but not at that place again. My experiences are good with that technique so far.
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby batadunbata » Sat Aug 05, 2017 6:43 pm

Interesting, I'm not sure exactly where the hole would start, and what direction it would be drilled?

Dugura is very hard, so it's brittle and prone to splitting, and the rim is very thin, so I'm not sure it could take drilling, even if it was a very small bit. It's noticably harder than Lenke and Gueni. More like Gele.

On luthier forums I've read about people gluing small pieces of wood on the inside like a bandaid, to provide reinforcement to resist splitting. They use something thin, like veneer, and cut it into a diamond/rhombus, or long/flattened hexagon, and use multiple pieces along the crack.

Interestingly, I can contact the guy who brought it from Africa in his luggage. I bought it from someone he sold it to, so I'll ask him more about it. Maybe he did the repair, or knows what kind of glue was used.
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby djembefeeling » Sat Aug 05, 2017 7:29 pm

Yes, I know they are brittle, don't like that kind of wood too much. I would drill from the top to the bottom, in the direction of the crack, only 2 centimeters, and I would start wirth a very small drill and use a small wooden dowel. But you may be right. Perhaps you don't need to and the crack is ok like that. I do that only for shells that are precious to me and that I want to make sure to last as long as possible.
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby batadunbata » Sun Aug 06, 2017 7:01 am

I'm having trouble picturing what you mean, so the drill goes into the crack?

It might be brittle and hard to work with, but I like how it sounds. I like all the woods though, I'd love to have one of each :)
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby djembefeeling » Sun Aug 06, 2017 8:04 am

O.k., I just made a photo. Don't have a shell, unfortunately, so imagine there is no skin. You drill right into the crack, yes. The dowel supposedly diverses the the tension in the wood that caused the crack. But I remember having done that once with such a djembe from the Senegal, now, and the wood was really brittle and it was messy work with that kind of wood...
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby drtom » Mon Aug 07, 2017 5:50 am

batadunbata wrote:Dugura is very hard, so it's brittle and prone to splitting, and the rim is very thin, so I'm not sure it could take drilling, even if it was a very small bit. It's noticably harder than Lenke and Gueni. More like Gele.

On luthier forums I've read about people gluing small pieces of wood on the inside like a bandaid, to provide reinforcement to resist splitting. They use something thin, like veneer, and cut it into a diamond/rhombus, or long/flattened hexagon, and use multiple pieces along the crack.


You know, I'm about to start asking YOU for advice.
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby the kid » Tue Aug 08, 2017 12:12 pm

Dugura is very hard, so it's brittle and prone to splitting,...... It's noticeably harder than Lenke and Gueni. More like Gele.


I have had over 20 dimba/Dugura drums and don't find it brittle at all. What happens in senegal and gambia, where much of the drums from this wood come from, is some carvers will carve anything so many poor drums from bad wood get made and sold.

I've seen some poor carving from there too. Many drums are sold in markets that are simply patched up with saw dust and glue with really rough carving work. But when a good carver gets a nice piece of wood they can produce a nice drum.

Drums from decent Dimba/Dugura wood are solid and last like any other hard woods.
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Re: Restoring Djembe Questions Photos - Soundhole etc.

Postby batadunbata » Wed Aug 09, 2017 6:57 am

That makes sense Djembefeeling, thanks for the visual too lol. I feel scared for that djembe!
I didn't understand at first, but I think I get it. The dowel increases the surface area for the glue, and also changes the forces from lateral to round, which distributes the energy, a bit like the spokes on a bike wheel. It would take some confidence to do it, but I trust your experience that it works. This crack repair seems pretty solid, but I'll keep that in mind if it breaks or for future repairs.

Heh, thanks DrTom, I'm a sponge for info and love theorizing, but have no actual experience repairing them yet :)

I hear ya on the quality variation The Kid.
That could be what I've got here. It seems strong overall though, so I wonder if they carved it green and it cracked while drying. Wood is way harder to carve when dry, and unless you take measures (like keep it in a plastic bag half the time) it will dry too quickly and crack.

It's very hard, so I'm sure you're right about strength and durability. But the harder a wood is, generally the more brittle it is because it's less flexible. Woods that are significantly harder than Djembe woods, like Ebony and African Blackwood, are also brittle and prone to cracking, especially while drying. They're strong in most aspects, but that's the weakness of being hard.
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