self made useful tools or templates for violin making/repair


Recommended Posts

17 hours ago, David Burgess said:

A friend of mine recently purchased a high-performance boat from the person I had originally sold it to. The original hull (produced by a high-performance boat manufacturer) incorporated many parts made from wood, including balsa-core skinned with fiberglass. But I added many other parts made from wood.

So my friend, shortly after purchasing the boat called me up, after discovering that so many of the parts I had added and fabricated were made of wood, teasing me about that, since he has known for at least least 30 years that I am a violin maker.

I love stuff like that, jokes between friends, with no intention whatsoever of hostility.

Which is no doubt enhanced by the factor by which that friend's sense of humor is warped.

Link to post
Share on other sites
  • Replies 142
  • Created
  • Last Reply

Top Posters In This Topic

So here is a simple one that works pretty good... latex tubing in the end of a standard syringe... fill with hot glue press down gently to seal around the edges and with the plunger force glue into cracks.  Had occasion to use it again this morning ... worked like a charm and thought I would share... Cheers, Mat

Glue Syringe.jpg

Link to post
Share on other sites
12 hours ago, Mat Roop said:

So here is a simple one that works pretty good... latex tubing in the end of a standard syringe... fill with hot glue press down gently to seal around the edges and with the plunger force glue into cracks.  Had occasion to use it again this morning ... worked like a charm and thought I would share... Cheers, Mat

Glue Syringe.jpg

If I understand this correctly, with the rubber plug the amount of glue being pressed out can be controled better? 

I suppose you heat the glue in the syringe directly in the water bath. 

Link to post
Share on other sites
16 hours ago, Mat Roop said:

fill with hot glue press down gently to seal around the edges

Are you glue sizing the edges so that it becomes harder so that you can scrape the channel without tear out?   If so why not a brush?  Not sure what you mean by sealing the edges"

Link to post
Share on other sites
5 hours ago, Andreas Preuss said:

If I understand this correctly, with the rubber plug the amount of glue being pressed out can be controled better? 

The rubber tubing at the end creates a seal when pressed against the wooden part, allowing the syringe to apply high hydraulic pressure to the crack.

I do something similar, but mine uses an O ring at the end. It's described and pictured in The Strad article I wrote about ten years ago. It's a little tricky to use though, because the rubber wants to slide around on the glue, so best to practice on some scrap first.

Link to post
Share on other sites
17 minutes ago, David Burgess said:

Neat. What did you use to gasket between the fiddle and the vacuum tube?

I have what looks like a flat, fairly firm suction cup that has a hole in the back to connect to the tubing.  It came with a complete Mityvac hand vac set I found on the road near Shar years ago.  I use a vacuum pump with a bleed valve while doing such things though.
Come to think of it, I've also used that technique while regluing the center section of back center joints without opening the instruments. I also reinforced the joints with linen.  I can think of two violas I've done that on 20+ years ago that are played hard and doing fine.  The not very open center joints were causing enough discontinuity of plate vibration that the sound suffered significantly.

Link to post
Share on other sites
38 minutes ago, Mark Norfleet said:

I have what looks like a flat, fairly firm suction cup that has a hole in the back to connect to the tubing.  It came with a complete Mityvac hand vac set I found on the road near Shar years ago.  I use a vacuum pump with a bleed valve while doing such things though.
Come to think of it, I've also used that technique while regluing the center section of back center joints without opening the instruments.

How did you do that? Where did the vacuum cup go and where was the glue applied (and how)?

Link to post
Share on other sites

A low-tech method I have used for getting glue into cracks:  put a bead of glue over the crack, cover it with tape, and squish it in with fingers.  The tape has to be bigger than the glue bead (to seal at the edges), and the tape can't be too sticky as to lift off varnish when removed.  Probaby too risky for a high-value instrument.

Link to post
Share on other sites
4 hours ago, David Burgess said:

The rubber tubing at the end creates a seal when pressed against the wooden part, allowing the syringe to apply high hydraulic pressure to the crack.

I do something similar, but mine uses an O ring at the end. It's described and pictured in The Strad article I wrote about ten years ago. It's a little tricky to use though, because the rubber wants to slide around on the glue, so best to practice on some scrap first.

Thanks David... you explain better than I!  If you know which issue of the Strad your article is in... I'd love to read it (I have a bunch of old issues). 

 

2 hours ago, Mark Norfleet said:

I have what looks like a flat, fairly firm suction cup that has a hole in the back to connect to the tubing.  It came with a complete Mityvac hand vac set I found on the road near Shar years ago.  I use a vacuum pump with a bleed valve while doing such things though.
Come to think of it, I've also used that technique while regluing the center section of back center joints without opening the instruments. I also reinforced the joints with linen.  I can think of two violas I've done that on 20+ years ago that are played hard and doing fine.  The not very open center joints were causing enough discontinuity of plate vibration that the sound suffered significantly.

I have, for a long time,  thought about the concept that is used to fill stone chips in windshields... easy enough to use on an opened violin, but how to use it on an assembled instrument? Guess I'm not inventive enough:(.

 

 

Link to post
Share on other sites
9 hours ago, Andreas Preuss said:

If I understand this correctly, with the rubber plug the amount of glue being pressed out can be controled better? 

I suppose you heat the glue in the syringe directly in the water bath. 

Yes... the glue is contained mostly within the rubber tubing area and it slides easily along the crack... but it is a careful balance between downward pressure of the tubing the end of the syringe against the violin finish and the pressure of forcing glue out of the syringe.  I heat the syringe with the hot water from the bath, then draw in the glue and apply to the preheated crack.

Link to post
Share on other sites
3 hours ago, Mat Roop said:

Thanks David... you explain better than I!  If you know which issue of the Strad your article is in... I'd love to read it (I have a bunch of old issues).

February 2005. I think it's been long enough that I can post a PDF version of it, although the photos in the PDF version aren't of very high quality.

http://www.burgessviolins.com/Strad glue article.pdf

Link to post
Share on other sites
13 hours ago, Woodland said:

I made this hand-cranked disc sander this fall out of 1/2” Baltic birch plywood. It’s no Alberti design, but it didn’t cost $900 either, more like $20 in materials. Still tweaking it.

There we go, another cool idea. 

Btw adding weight (ideally a ribbon of lead around it) to the wheel would give it a bit more punch once you have accelerated it. 

One might also think about adding a gear to get a higher speed. 

This one risks to land on my tool wish list for self made tools.

Thanks for posting!

Link to post
Share on other sites
15 hours ago, David Burgess said:

Nice. What is the purpose of the second wheel on the crank side?

The second wheel on the crank side is just that, the crank. Originally the handle was just a piece of dowel mounted directly on the disk, necessitating the disc. I later added a crank handle with rotating know directly to the hub. The crank disc also is something the axle affixes too. Between each disc I made large leather washers impregnated with beeswax and mineral oil. The sanding disc cuts square however there is a bit of play in it. If I end up remounting the discs I would clamp them together against the washers more firmly (while the glue was drying on the axle) to remove the play, but that would make it slightly harder to turn.

I considered gearing the crank for higher speeds, but I just decided to keep it simple and low speed, this is more about convenience and "precision" rather than speed.

Link to post
Share on other sites

That's nice... but it needs a motor:)

Here are a couple of disc sander/grinders I put together.

The most recent one uses the motor, disc, switch, and miter hardware from a cheapo Harbor Freight belt/disc sander.  The discs are inexpensive diamond discs, held on with magnets.  While I primarily made this to sharpen carbide lathe tools (which it does fantastically), I have also been finding it very useful for other things as well. (That's my peg lathe in the background).

282145132_200818diamonddiscsharpener1.jpg.e69a92e020bb97b25f4121cd0a0ff7d5.jpg

This second one I made some time ago, using an ancient Bodine gearmotor (low RPM) that I accumulated from who-knows-where in prehistoric times.  The disc plate I had to fabricate myself, and uses stick-on sanding discs.  It is primarily for soundposts.. the angle can be set to a precise angle, and the sled traveles in a groove at a very slight angle to the disc, so the length can be adjusted very precisely.  I also use it to trim saddle ends, setting the angle to zero

.2017634053_SoundpostSander2160426.JPG.4ed820859daa6a8ef095f9381d94a0e7.JPG

Link to post
Share on other sites
4 hours ago, Don Noon said:

That's nice... but it needs a motor:)

Here are a couple of disc sander/grinders I put together.

The most recent one uses the motor, disc, switch, and miter hardware from a cheapo Harbor Freight belt/disc sander.  The discs are inexpensive diamond discs, held on with magnets.  While I primarily made this to sharpen carbide lathe tools (which it does fantastically), I have also been finding it very useful for other things as well. (That's my peg lathe in the background).

282145132_200818diamonddiscsharpener1.jpg.e69a92e020bb97b25f4121cd0a0ff7d5.jpg

 

.

 Don, do you just get the "inexpensive diamond discs" and put rare earch magnets on the other side of the aluminum drive plate , to hold it on?

Link to post
Share on other sites
30 minutes ago, Jeff White said:

 Don, do you just get the "inexpensive diamond discs" and put rare earch magnets on the other side of the aluminum drive plate , to hold it on?

Yes, I drilled some holes in the aluminum disk and glued in round rare earth magnets.

I noticed that searching for diamond "disk" works a lot better than "disc", and they're only a few dollars on eBay.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    No registered users viewing this page.