Measurment advice

Lillian · Post by **Lillian** » Thu Nov 13, 2008 11:55 am

In about two - three weeks I am going to be afford the opportunity to spend some quality time with two Martin Palors that have been dated to between 1835 and 1850. The owner has no qualms about me putting my grubby hands all over them. I promise to wash my hands first, but while I'm handling them, I want to get all the information I can out of them. I'm looking for suggestions on taking measurements and copying profiles. I have a couple of LED flashlights that I can put inside and not worry about them getting hot. I'll try them out on the piece of crap guitar that set me down this road in the first place. My camera isn't the greatest, but I'm hoping that it will be sufficient for recording the bracing. I would like to copy the neck profile if possible. I've read about Frank Ford's technique, but the epoxy stays soft too long for me to use it. Plaster of Paris will be too messy. Thoughts, tools, techniques?

James Mc · Post by **James Mc** » Thu Nov 13, 2008 12:32 pm

Hi Lillian

I have a profile copy tool from back in my days as an engineer. All it is is a bunch of flat metal strips bunched together in a rectangular frame with a locking bolt. I found something similar online at a tool supply shop, probable available at most large hardware stores.

http://www.woodcraft.com/product.aspx?P ... ilyID=4860

Wouldn't be hard to make something up with a bunch of timber strips (paddle pop sticks) in a little frame.

As for measuring braces etc inside the guitars... you could ask if you could remove the tops

Apart from that I'm not going to be of much help, I've done the mirror on the stick thing with a little torch a bunch of times and usually end up estimation most sizes.

Bob Connor · Post by **Bob Connor** » Thu Nov 13, 2008 12:36 pm

Lillian

Have a look on the Unofficial Martin Guitar Forum.

There is a library of bracing patterns where the lads have put a light source inside their instruments and taken pics of the braces from the outside.

Fascinating stuff and really gives you a true representation of what's happening with the bracing patterns.

Lillian · Post by **Lillian** » Thu Nov 13, 2008 12:51 pm

Thanks James, I had forgotten about those. I might even have something similar squirreled away somewhere.

Bob, that's where I got the idea from. It gives a great view of the bracing pattern, but nothing for thickness. I don't think that my arm is small enough to reach through the soundhole, but I might be surprised. I figured mirrors and a stub of a ruler.

josh_cain · Post by **josh_cain** » Thu Nov 13, 2008 1:34 pm

To measure thicknesses you could use Verneir (spelling??) Calipers.

Lillian · Post by **Lillian** » Thu Nov 13, 2008 1:47 pm

I don't think what you had in mind will work for the brace dimensions, but I think I know what just might. Turners use a caliper that has long arms on one side of the pivot and shorter ones on the other. You measure the distance from the gap of the side not being used. I'll have to see if I can talk Michael out of his for the weekend and do a dry run with them.

Thanks Josh!

kiwigeo · Post by **kiwigeo** » Thu Nov 13, 2008 5:53 pm

If youre using one of those profile tools with the metal pins....put some masking tape on the surface youre contouring to protect from damage. The pins on those things can damage delicate finishes.

kiwigeo · Post by **kiwigeo** » Thu Nov 13, 2008 5:56 pm

For brace dimensions.....try waxed paper over the brace and then mold some plasticine over the brace to get the contour of same. The wax paper protects the brace from the plasticine.

There are a bunch of articles in the GAL Big Red Books on measuring up instruments......

Allen · Post by **Allen** » Thu Nov 13, 2008 6:14 pm

My local art supply shop has those contour gauges in stiff plastic bristles instead of the steel ones. Probably a lot more gentle on delicate finishes.

I think that the plasticine is probably one of your better options for brace profiles. Might even be able to give you a good idea of dimensions as well if your careful. The other option might be to use some of that "Friendly Plastic" that you heat, mold and let cool to take the shape that it's pressed against.

Really looking forward to seeing what you come up with.

Lillian · Post by **Lillian** » Thu Nov 13, 2008 11:37 pm

What is plasticine?

I'm going to pick up one of the plastic ones. I don't want to take any chances.

DarwinStrings · Post by **DarwinStrings** » Thu Nov 13, 2008 11:52 pm

Hi Lillian
I think you might know Plasticine as Modeling Clay but I'm not %100 sure.

Jim

WaddyT · Post by **WaddyT** » Fri Nov 14, 2008 1:19 am

Allen mentioned the moldable plastic. Stew Mac sells plastic beads that can be heated in a bag in warm water, then molded to shape. It holds it's shape when cool, then can be re-melted and re-shaped over and over. It could be used for this very well. They sell it for making glue cauls.

Allen · Post by **Allen** » Fri Nov 14, 2008 7:00 am

Welcome to the forum Jim.

Lillian, Plasticine is just the trade name for a product sold in Canada by one of the large toy manufacturers. Common name would be modelers clay.

Lillian · Post by **Lillian** » Fri Nov 14, 2008 2:46 pm

Modeler's clay I have. Cool. I'm so looking forward to this.

DarwinStrings · Post by **DarwinStrings** » Fri Nov 14, 2008 7:35 pm

Thanks for the welcome Allen, You are almost as far north as I am and I imagine you have to buy everything mailorder up there too.

Jim

kiwigeo · Post by **kiwigeo** » Sat Nov 15, 2008 12:03 pm

Welcome to the forum Jim,

Like the nickname.....toejam certainly something you see alot of around Darwin.

Cheers Martin

Allen · Post by **Allen** » Sat Nov 15, 2008 4:46 pm

Yes Jim, everything our southern brothers take for granted in purchasing just around the corner is treated with blank stares from across the counter everywhere I go in Cairns.

It's got to the point that I don't even bother with the frustration of trying to purchase locally anymore. Something as simple as screw-in inserts for your bolt on neck can't be had locally.

DarwinStrings · Post by **DarwinStrings** » Sun Nov 16, 2008 4:27 pm

Thank you for the welcome too Martin

Agreed, at least we can keep our toes exposed, it's the covered bits that can suffer most.

Yes Allen, "blank stares" or "never heard of it" or "I think we can order it from down south but it will take two weeks" then they get the order wrong and it is another two weeks.....still I love Darwin.

Oops , where am I, ok I remember, how is that pair of martins parlors going Lillian.

Jim

Lillian · Post by **Lillian** » Sun Nov 16, 2008 4:36 pm

No problem Jim. I enjoy the commentary.

I don't get to check out the parlors until the first Friday in December.

Allen · Post by **Allen** » Sun Nov 16, 2008 5:49 pm

Lillian, there's a big group of us that would love to be looking over your shoulder when the time comes. Good luck with this.

James Mc · Post by **James Mc** » Sun Nov 16, 2008 10:17 pm

Allen wrote:Lillian, there's a big group of us that would love to be looking over your shoulder when the time comes. Good luck with this.

and an engineer who hates messing around and just wants to pull em to bits and see what makes them tick

Lillian · Post by **Lillian** » Mon Nov 17, 2008 3:19 am

James, you aren't the only engineer running loose on the forum.

My mom found a watch in my sock drawer that I had taken a part and couldn't get back together. I must have been about 11. Didn't get another watch until I was 14.

Lillian · Post by **Lillian** » Thu Jan 15, 2009 8:51 am

Saturday is the day, unless the skies open up again and dump whatever form of precipitation it chooses on us.

I know I'll be pulling the strings off of it and want to replace them. The owner isn't a player and hasn't a clue as to what's on them right now. I'm thinking silk would be an appropriate choice. What say you all?

kiwigeo · Post by **kiwigeo** » Thu Jan 15, 2009 4:03 pm

Lillian wrote:The owner isn't a player and hasn't a clue as to what's on them right now. I'm thinking silk would be an appropriate choice. What say you all?

I say pull the thing apart and tell the owner youure looking for the wedding ring you dropped into the soundhole

Lillian · Post by **Lillian** » Fri Jan 16, 2009 3:02 pm

Ah, thanks Martin. I think I'll try to avoid doing that. It might be hard putting the pieces back together.

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