A few thoughts.

Well, I'm giving here a few thoughts on the kind of restoration I'm busy with.

I've performed quite extensive plugging and crack repair using wood patches/plugs. Some will certainly think that it might affect the sound. Well, to be honest, I have no idea. Maybe a slight impact. But I personally think that a heavy piece of cast metal like a tom mount on a bassdrum affects the sound more than a few small wood patches.

Some might also think that I shouldn't denature the style of an old drumkit, and that I should strive to restore it to its original condition. I don't do it for two reasons. 

First of all, I only work with less valuable models, that you can come across for almost nothing. My concept is to take advantage of the built quality of those drumkits, but give them another look. 

See it like some sort of upcycling rather than pure restoration. 

Secondly, I try to keep it on a low budget, and find alternative solutions in terms of finish and missing parts. I'd rather source cheap SONOR German made hardware leftovers than try to look for that original drum part. 

I love a players' drum, an instrument that's meant to be banged.

Staining.

Here we go. I said no turning back.

It went fine. Not perfect, but let's not forget that these are old shells, and that they weren't made to be stained. If you want perfect stain, my opinion is that you need to veneer the shells.

I read some articles on the internet on how to get a more even staining by applying one coat of thinned shellac sealer before staining. But I actually chose to follow CLOU's instructions and work directly on bare wood.

I actually rubbed the first coat working in the direction of the grain, and then I applied a second coat when still wet, by making circular movements with the sponge.

The overall tone is good and will look stunning under a high gloss clear poly.

The wood patches actually blended nicer than I thought they would.

Anyway, I like the green tone, it's not too dark, not to yellow, kinda classy. Next picture gives a good idea of what it looks like.

And masking the inside of the shells was definitely a good idea.

Dunkelgrün 158.

Staining wood is a one shot operation. Once you start there's no turning back without re-sanding everything. So a little preparation is a must.

First of all, to be able to work properly and comfortably, I built two shell racks out of furniture chipboard leftovers - found on the street. I'll use the low one for working (at an optimal working height of 106 cm - 3' 6") and the other one for storing the other two shells when drying.

Secondly, I masked the inside of the shell with plastic foil and painters' tape (I used das Schonende from STORCH), since I don't want stain or lacquer to make a mess on the oiled finish. Doing it properly is time consuming, but it'll save you time in the end. You'll see.

Btw, plastic foil is upcycled IKEA HDPE mattress wrap.

I've always wanted a dark green drumkit but never got the chance to own one.

The stain is Dunkelgrün 158 from the German CLOU brand. It's inexpensive and an instrument builder's favorite in Europe - from what I see when googling.

I used two packs to make sure I have enough stain (500 ml or 1/2 quart) in case I should apply two coats. You just have to mix it with warm water, I used distilled water for security.

Note: the glass container used to be filled with some delicious Valfrutta organic tomato sauce. Highly recommended for all your pasta cravings.

I'll try the sponge application method. I actually cut a sponge in two to have more control.

As you can see, I try to stay organized and have a nice work area: clean table, convenient container, natural light, handwritten hipster lettering...

Applying CLOU stain proved to be very very easy. You need to be careful not applying too much (or it will drip) or too little (you'll get uneven staining). But it's overall very controllable, fixing lighter of darker spots can be done by rubbing the sponge as long it's not completely dry.

Here's the finished staining test on the 14" shell - that I'll be using for building the 7 1/4 snare drum by the way. The outside will be lacquered, so using the shell for testing was no issue.

I'm pretty happy with the result. Deep green out of the box, that beautifully enhances the vertical beech wood grain.

Definitely one fourth slotted rod.

Just arrived in the mail today.

I can't think of another tool that would be more vintage SONOR specific.

Yep. A set of taps and die in BSW 1/4 20 thread, chosen by SONOR for their famous original slotted rods.

Mmh those hard to screw lugs working smooth again...

I bought them on eBay, the price was fair and the quality looks alright.

They are indeed a perfect match to the old SONOR thread (here with some FORCE 2000 hardware)

Sanding and woodpaste filling.

After spending quite a few hours on plugging and repairing, I'm now ready for sanding the shells.

When I started this project I considered veneering the outside of the shells, and then staining. After some time working on it, I realized that I kinda liked the typical Sonor beech wood grain, and that it was a nice base to start from afterwards.

Nice grain indeed. The four holes are those of the disappeared badge.

I'll keep the veneering idea for the snaredrum I'll built with the 14x10 tom.

In order to sand off glue leftovers (on the outside), sealer (on the inside) and finishing plugs, I started with 60 grit. To make sure I would follow the shape of the shell when sanding, I carved sanding blocks out of polyurethane insulation panels, matching each diameter.

I then kept on sanding - by hand - along the grain using 80 and 100 grit.

It's now time for filling small dents and joints. I used what I call a "noble" woodpaste, made with a nitrocellulose binder called "Pafuki" (from Berger-Siedle, a German brand) and wood flour.

Note: I got much of my supply from my uncle's cabinet company. Don't hesitate to contact your local cabinet maker / wood floor company, I'm sure they won't mind giving away some products / scrap wood / plugs.

 In this case, I'm experimenting with a 2 step process, filling deep cracks using a thicker paste, sanding and then filling small dents using a thinner cut (see below).

Here are some pictures of the shells, just before staining.

Patchwork went fine and sits flush with the shells. Only little issue was the wood tone of the bassdrum patch. I think I used - without realizing - natural beech, that's whiter than steamed beech. I'll try to fix that during staining.

The inside was sanded with 120 and 150 grit. Since it will be oiled, I decided not to go further than 150 to keep the wood feel.

Inside of the bassdrum. The shell must be 40 years old.

The outside was also sanded with 120 / 150 then rubbed with clean water to raise the loose wood fibers. When dry, they were sanded off with 180. Getting rid of the tiny loose fibers guarantees a more even staining.

Before rubbing water

After

 I am quite happy with the floortom repair that turned out pretty nice and barely noticeable.

The patchwork on the 13" rack tom shows the difference between white beech and steamed beech.  But overall satisfying.

Next step is staining, but first I'll have to mask the inside of the shells. Inside oiled finish will be done after outside is varnished, I don't want any oil messing up the outside surface preparation.