Refurbished Factory Bandura

[Andy Birko]

I haven't posted anything in a bit so I thought I'd show off a little bit of my recent work.

I just completed a re-finish of a 1970's vintage factory made bandura for a friend of mine. Finish is Cardinal lacquer, my first time spraying nitro. Past experience was with waterborne and varnish. Really like how it came out.

The work involved stripping off the original finish which was some sort of lacquer or possibly shellac that was over a really thick layer of this nasty green primer. After I stripped it it seems that the thick primer was there because it was easier to sand flat than the bare wood. General lack of care by the factory guys when carving etc was cleaned up as well (e.g. undercutting the scroll, rounding harsh edges etc…)

Originally, where the sound hole is this instrument had seven dime sized sound holes. I used my CNC machine to open up the sound hole to what you see.

Banduras of this type typically have 12 bass strings - C# to C chromatically so i added a lucky 13'th bass string and made a new bridge so that it goes C to shining C now (unfortunately the customer/friend is Canadian though)

Finally, once it was strung up the re-tune mechanism needed to be regulated.

The end result was shocking - removing all the green goop turned it in to a completely different instrument. Factory banduras sound "ok" at best, usually aren't very responsive and lack a midrange entirely. This instrument, while in my opinion still doesn't sound as good as one of my hand made instruments, sounds pretty darn good and is now a musical instrument at least. To put it into guitar terms, I'd say the re-finish and opening up of the sound hole moved this from Ovation territory to Martin/Taylor territory.

[Andy Birko]

Here's some in process shots:

The back with the green goop starting to come off:

Using a pen to align the CNC machine to cut the sound hole. I made a program that increased the diameter by a few thou every time I pressed go to sneak up on the right size. Wanted it to be as bit as possible while still having a nice border inboard of the rosette.

Cutting the sound hole:

And the finished product:

Here's everything ready for finishing:

[Andy Birko]

And one last shot - here's the burst in process:

[Jason Rodgers]

What a resurrection! Great work!

[Chuck Tweedy]

Great job Andy.
Was the Cardinal lacquer easy to work with?

[Mark Swanson]

Many factory guitars, the cheaper ones in particular, have very thick finishes that definitely affects the tone in a bad way. In the commercial market, it's all about looks...Good work Andy!

[Andy Birko]

Great job Andy.
Was the Cardinal lacquer easy to work with?

Thanks Chuck.

Was it easy to work with? I'd say "yes" with some asterisks. The only nitro I've sprayed before was rattle can like a decade ago or maybe even more. I followed the instructions on the LMII site except that I finished all of my vinyl sealer coats clear and sprayed the color in the lacquer itself. The biggest nozzle I have for my spray gun is a 1.2mm and it turned out that it was a little too small for the lacquer. It worked fine for the sealer but I was getting some pebbling with the lacquer so I thinned it down maybe 10% with the Cardinal thinner and that fixed it. I think a 1.4mm nozzle would have worked better and I'll probably have to buy a nozzle/needle set in that size. Cardinal states that this stuff is pre-thinned and can be sprayed right out of the can and I believe them, just not with the small needle I had. Perhaps in other guns it would work fine.

The down side is of course the solvent. It was getting cold outside when I sprayed it so I built a little shanty in the garage (you can see part of it in the burst picture) which I heated to spray. The stench was pretty terrible but it didn't get in the house much so it was bearable. The respirator did a good job of filtering out the nastiness as I couldn't smell any solvent when wearing the mask until the last bit of spraying I did which was the bridge. I threw away those cartridges so I'm not tempted to re-use them.

With the nozzle issue solved, it went down great. For the most part, I was getting very smooth coats with little orange peel. Bandura bodies are obviously pretty big so there were some spots where I'd get over spray near the spot I was spraying that left a so-so finish but over all it was good. I've never had success buffing a scroll without burning through so I actually did no leveling or sanding of any type on the actual scroll itself. What you see in the picture is straight off the gun.

Over all, I found it easier to spray than either EM6000 (which I used before - that and its older brother USL) or Varnish. Coats went on thicker and with less runs than either of the other ones I've sprayed. Leveling and buffing went well too. I'm still having problems getting rid of the really small scratches that show up only under certain angles of light but I imagine that will go away with more practice.

This instrument hung about 4 weeks before final leveling and buffing but I did another instrument at the same time which I buffed after 2 weeks and it worked out just as well. Cardinal recommends 7 to 10 days. I really like that this stuff is water clear and doesn't add any color to the wood. That allows me to control any tinting the way I want.

Over all, I'd really like to use this in the future. The hassles about finding a place to spray would be the only things that might hold me back in the future. Everything worked fine in the shanty but overspray did escape and the whole garage was covered in a fine dust of dried lacquer.

[Michael Lewis]

. . . "and the whole garage was covered in a fine dust of dried lacquer."

Take care to avoid that in the future as it is what has caused some aircraft hangars to blow up from the dried over spray settled on the floors. It only takes a spark to set it off. Either make a set up (spray booth) to capture the over spray or do your spraying outside where it can't accumulate to any significant degree.

I have enjoyed seeing pics of your previous works and recall a recording that was rather impressive. Carry on.

[Chuck Tweedy]

Thanks for the info Andy.
I'm climbing the learning curve of sprayed finishes, and am thinking of taking on Cardinal. Seagraves works fine, but I'd like to try others to have options.
My gun has a 1m tip, and I wonder if I can get a larger nozzle/needle for it. Its a pretty generic gun.
Anyhow - you finish looks great in these pictures, bravo!

[Bryan Bear]

Looks great Andy! I bet you friend is very pleased.