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I used to just glue these bone point protectors to the points. Now I drill them out and press in brass brads with the heads removed. Even H H G doesn't hold these that well due to the end grain of the points. It only takes me a few minutes to add these along with hot hide glue and the connection is super solid.

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http://www.cushmanguitars.com/.

A man who carries a cat by the tail learns something he can learn in no other way.
Mark Twain

I bet they look great once finished, too!

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"Act your age, not your shoe size" - Prince

Very nice from what I can see. Original Loar F5's were dovetailed on top and bottom into the binding and purfling. That is what held them in. Probably done in HHG. I hate doing bone points on the celluloid bindings. Just so hard to file...
How bout some photos of the rest of the rest of it!

Nice idea. Very pretty looking mandolins too!!

Thanks Chris, Haans, and Kevin. I'll post some more pics in another thread. I have 4 mandos at this stage of construction. I have to agree with you Haans. I hate celluloid binding. The binding I used on these is black and white fiber (vulcanized celluloid). The final look is different from an old Gibson but the bone protects the fiber from getting dinged or dislodged. I have these sanded out to 120 grit. I will go to 220 and then mask them off, dye and finish them. 3 sunbursts and 1 amber is the plan. Here's a pic of these protectors after being shaped.

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http://www.cushmanguitars.com/.

A man who carries a cat by the tail learns something he can learn in no other way.
Mark Twain

Oh, you misunderestimatestood, Matt. I most always used celluloid for points unless it was one of my F5C Loar classics. I love celluloid, hate bone points and making dovetails into the binding there is a B.
You got a lot of work piled up there...

Sorry Haans, I misunderstood what you were saying. However, I don't like nitro cellulose binding. The main reason is that I am allergic to it. When scraping nitro cellulose binding try not to contact it with your bare hands as nitrogen will pass through your skin and into your system. Nitrogen can build up as the body has trouble ridding itself of nitrogen. I was made very sick this way about 15 years ago. Ever since I have used black and white fiber. I like the fiber very much as it will not shrink or crack with the passage of time. It bends easily around a scroll with a little heat. It is also easy to glue up with hide glue and that makes clean up go super smooth. Your right. I do have a lot of work piled up but I can finish 4 almost as fast as I can do 1.

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http://www.cushmanguitars.com/.

A man who carries a cat by the tail learns something he can learn in no other way.
Mark Twain

Nitrogen? How do you deal with breathing?

There are tons of toxic things in nitro lacquer - I imagine that the dissolved nitrocellulose is not among the main ones. Does solid nitrocellulose pose a risk? I imagine that the glue we use to glue it to the guitars is far worse.

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Jim Kirby
kirby@udel.edu

I don't think that breathing small amounts of dust is dangerous. The nitrogen I was exposed to came from scraping plastic binding made from nitrocellulose without having gloves on. I think its called celluloid nitrate. I scraped loads of this stuff without gloves on day after day. The nitrogen is absorbed easily through the skin. Small amounts are no problem. But nitrogen can build up quickly because the body can not remove nitrogen very well. Too much nitrogen in the blood system is very bad for your health. I read that some film archivists have had this problem from handling old cellulose film. A small amount won't hurt you but too much is bad news!

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http://www.cushmanguitars.com/.

A man who carries a cat by the tail learns something he can learn in no other way.
Mark Twain

Nitrogen gas composes over 70% of the earths atmosphere. I expect you must be referring to nitrogen compounds of some sort?

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Steve Smith
"Music is what feelings sound like"

Cush, what kind of symptoms did you have when working with celluloid?

What is in the atmosphere has little impact on Nitrogen levels in the average human blood steam. As I said, nitrogen can enter the blood stream through the skin. That is how an excess of nitrogen can get in the system. Celluloid binding plastic contains enough nitrogen to be classed as an explosive substance. Nitrogen in excess in the blood system causes wild swings in blood pressure from high to low along with a host of other circulatory problems. Everyones tolerance is different. But like I said, this problem is well known to film archivists. Some people are affected more than others, but who is to know, so I just thought I would mention this to save the next guy from what I went through ( I thought it was going to kill me). No kidding!! I won't even touch the stuff. Not to mention it is much more costly than fiber binding. I can bind about 14 mandos with a single 12 dollar sheet of fiber!

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http://www.cushmanguitars.com/.

A man who carries a cat by the tail learns something he can learn in no other way.
Mark Twain

I had no symptoms while I was working with it so much as after working with it.The symptoms I had were BP swings, weakness and mild seizures. I was sick for many months I don't know exactly how long it was. If affected with this take large doses of Vit. C.

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http://www.cushmanguitars.com/.

A man who carries a cat by the tail learns something he can learn in no other way.
Mark Twain

Not trying to be contrary. Nitrogen is in the blood normally due to partial pressure of the air we breathe. Divers (I am one) are well aware of the dangers of excess nitrogen in the blood and I have experienced it several times myself. It will outgas on its own while the body is at normal pressure. Anyway, I was just trying to figure out if it is gaseous nitrogen that is the problem here or some other form???

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Steve Smith
"Music is what feelings sound like"

I don't know why nitrogen affected me for so long. But I do know that others have experienced the same problems that I had. I read about a guy who restored old films and he had the same thing I had. He was also affected for many months. Why a diver can recover from an excess quickly and I didn't is something I don't understand. But the facts are as I have stated. It took a few doctors to even figure out what was causing my problem. Once I found an industrial doctor in Missoula he knew right away that it had entered through the skin and how to use Vit. C to help cleanse the system. Anyway I just wish someone would have warned me!

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http://www.cushmanguitars.com/.

A man who carries a cat by the tail learns something he can learn in no other way.
Mark Twain

A good warning since I would have never considered it could be a problem.

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Steve Smith
"Music is what feelings sound like"

I wore a dust mask. But I did not think contact could be a problem. As old film dries out it is slowly outgassing nitrogen till it finally disintegrates to an unusable state. Many old films have been lost to this aging process. The same thing will also dry out old celluloid binding. So when your binding is about the age of some of these old films they may be cracked and dry. My oldest guitar is bound in cellulose (17years). It already has cracks around the cut away area. So I don't think I will ever bind anything in it again. Fiber is different and hard to get use to, but I am so glad to have learned to use it. It has the properties of wood binding. I may be wrong but I think it helps tonally. It is very hard, light and durable.

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http://www.cushmanguitars.com/.

A man who carries a cat by the tail learns something he can learn in no other way.
Mark Twain

I am admittedly out of my element here; chemistry was not my strong suit. I don't think it is nitrogen alone (as in elemental nitrogen) that is the culprit. As Steve points out, your skin is currently surrounded by large quantities of nitrogen from the atmosphere. I'm guessing there is one or more nitrogen oxide(s) that form on celluliod as it ages/reacts with the atmosphere. These nitrogen dioxides are probably what pass through the skin and build up. This is just speculation as I have not really done any research here. I bet a google search on some combination of celluliod, nitrogen oxide, nitrogen dioxide, toxicity and perhaps a few other search terms would come up with something.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Whatever name you want to use is fine with me. It is the danger involved that is the point. Nitrogen can KILL you. Once in your system there is no way to go back. My family reminded me that it was over two years till I fully recovered from this. Like I said some people are more effected than others. I was exposed to a lot of this. A little is likely no problem but please be careful.

_________________
http://www.cushmanguitars.com/.

A man who carries a cat by the tail learns something he can learn in no other way.
Mark Twain