Hohner International (Bastari) D20/40/8 repairs

[Fanie]

Thank you Alex.

Should I first glue on these strips and finish it off and then glue on the big ends, or should I first glue on the big ends and then the small sides?

Thanks

[alex_holden]

3 minutes ago, Fanie said:

Thank you Alex.

Should I first glue on these strips and finish it off and then glue on the big ends, or should I first glue on the big ends and then the small sides?

Thanks

 

That's primarily a cosmetic choice about where you want the seam to be visible. I think I might do the large face before the sides.

 

What I actually do on my instruments is to route a rebate around the edge and glue strips of solid wood with mitred corners into it, then route a profile onto the border strip. That may be a bit advanced for a first attempt.

 

[Fanie]

Thank you Alex

[Fanie]

On 7/22/2022 at 12:14 PM, alex_holden said:

I recommend not using any glue that has water in it for veneering the end boards. If you do there's a high risk of them warping when the glue dries. Polyurethane glue, contact adhesive, or epoxy resin are some examples of glue that don't contain water.

Unfortunately I could not find Polyurethane glue, contact adhesive, or epoxy resin in my small town, so my only option was to use PVA wood glue. I apply the glue and then clamp it for 24 hours to try and avoid warping. So far it went well.

I also don't have brad point bit drills, so I made a chisel with a round side out of a 8mm steel bolt to cut the holes in the veneer and then finished the holes off with a dremel.

Some pictures of my progress:

 

Edited July 26, 2022 by Fanie

[Fanie]

So, I have been thinking what finish to put on the veneer when I am done. I have done a few wallnut gun stocks with a "London oil finish", using boiled linseed oil. It takes a long time to do- each very thin layer of oil must get dry before it is rubbed and a new layer applied. The old recipe went: once a day for a week, once a week for a month, once a month......

What do you guys think?

[alex_holden]

26 minutes ago, Fanie said:

So, I have been thinking what finish to put on the veneer when I am done. I have done a few wallnut gun stocks with a "London oil finish", using boiled linseed oil. It takes a long time to do- each very thin layer of oil must get dry before it is rubbed and a new layer applied. The old recipe went: once a day for a week, once a week for a month, once a month......

What do you guys think?

 

That should work. It depends on whether you prefer the raw wood sort of finish that you get from a drying oil, v.s. more of a glossy film that you get from a lacquer or varnish.

 

By the way, you can speed up the drying of oil based finishes with exposure to oxygen, U.V. light, and/or heat. I know some luthiers bake their instruments in a sort of U.V. tanning box to reduce the finish curing time from months to days.

Edited July 27, 2022 by alex_holden

[Fanie]

Thanks Alex, yes I prefer the raw wood finish more than a varnish finish. If I blow the oil with my wife's hair dryer, would there be a danger of warping the wood veneer?

[alex_holden]

9 minutes ago, Fanie said:

Thanks Alex, yes I prefer the raw wood finish more than a varnish finish. If I blow the oil with my wife's hair dryer, would there be a danger of warping the wood veneer?

I don’t imagine a hair dryer would have much effect. I was thinking more along the lines of leaving it on a sunny windowsill for a week or two, turning it occasionally to even out the UV exposure. 

[Fanie]

2 minutes ago, alex_holden said:

I don’t imagine a hair dryer would have much effect. I was thinking more along the lines of leaving it on a sunny windowsill for a week or two, turning it occasionally to even out the UV exposure. 

Yes, that is what I do, leaving it in the window in the sun. 😉