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Hi guys
I received my brace stock from Madinter today. I remember reading a thread recently where some of you said that Madinter sold excellent brace wood.
I'm still learning about woods etc and wanted your opinion on this wood.
In the picture (sorry about the poor quality) I have some bracewood from LMI which is perfectly quarter sawn but the wood from madinter looks to be 'rift sawn'.
Is this O.K.?
Thanks
Mat

that is not rif cut it is just a bit off quarter. it needs split to get more on quarter. splitting will tell the tail.

Hi Michael
Excuse my ignorance but I don't know what you mean.
Normally I just run the wood down the bandsaw - what do i do to use this wood?
thanks

That bottom piece in your picture needs split along the grain to true it up. This is done with a semi dull coal chisel and a mallet parallel the best you can to the grain. Once the split starts it will run along the grain run out of that piece.

The pieces LMI sent you this process has already been done and then dimensioned out 3/4 x 2 for your convenience. The other piece you have is raw brace stock.

I get it now
Thanks Michael

Splitting means cut it in half and send half of it to Michael......

the bad half will do.......

Ok - then send Michael the good half!

Sorry for the high-jack I am just having a great day!

Disagree. Split on a radius (90º to the rings) to find runout; Then saw at a right angle to the split face (after flattening that face). Don't split on a tangent (parallel to the early/latewood lines) and use that split face as a guide by sawing parallel to it. The wood won't split as cleanly on the tangential face, and you won't catch the runout.

_________________
Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Thanks Howard - but I already split along the grain, seems ok though.

Sometimes I feel a bit stupid asking these questions but would somebody please explain what 'RUN OUT' means.

You hear these terms all the time but untill somebody actually tells you what it means you just go along 'pretending' you understand

Thanks
Mat

Ummmm..sorry but Howard's right. Splitting parallel to the grain lines tells you nothing about runout.

_________________
Wes McMillian
Santo, TX
http://www.wesmcmillian.com

Here's hands down the best interent discussion I've seen regarding runout. Highly recommended reading! You're guaranteed to learn something you didn't know. May cause you to rethink a thing or two you thought you knew.

http://mimf.com/cgi-bin/WebX?128@68.aD2 ... @.2cb67fcd

_________________
Wes McMillian
Santo, TX
http://www.wesmcmillian.com

Print it out if you want to keep it. MIMF discussions fall into the abyss and don't resurface for a couple of years. The MIMforum is a great source of information, but it does have that one downside.

I think there have been a few discussions here on the same topic with pictures and examples. This is one of those subjects that maybe should be handled with less verbage and more hands(or dull hatchets) on practical observation. Grab a couple dollars worth of firewood and have at it, everything will make sense very quickly.

Rich

Read the MIMF discussion first then split your wood. Learn through my mistakes and there are plenty enough pictures there to help too.

I want to reiterate what Howard said. Runout is way more of a problem in bracewood than it being off quarter.

Somogyi wrote an article for American Lutherie many years ago showing the results of some testing he did. It showed, contrary to popular belief, that quarter sawn brace wood is not always the stiffest. Seems to depend on the density of the wood what grain orientation is stiffest.

But runout is always to be avoided.

_________________
http://www.chassonguitars.com

Don't confuse stiffness with strength. Runout determines the strength of the brace not the stiffness. Read the Linked discussion, you'll be glad you did.

Heavy runnout does seem to modify stiffness(at least in some situations I have tried to study) as well as strength in bits I have run across. In the case of curly wood(say curly Cedwood or Port Orford Cedar- this is figured wood, not reaction wood) I have noticed a decrease in longtitudinal, and actually an increase in cross grain stiffness(well in excess of what would be a typical range of stiffness). Reaction wood seems to produce more varied modifications in stiffness(density varies to different degrees in reaction wood so it is a bad example). Simple runnout do to cutting or milling off parallel to the split face is something I have not really tried to observed closely. The most I could say is the bits that have been off a few degrees higher than I would like may have or may have been modified, but I can really say how stiff the would have been if the runnout was reduced. I should probably try cutting a few bits and see what I find, it would be pretty easy to check. I agree though heavy runnout makes it much easier to break the wood, especially when the grain fibers are very short related to the face.

Rich

I don't think anyone would want to use curly woods for brace wood, would they?

Who was confusing stiffness with strenth?

_________________
http://www.chassonguitars.com

It's just the way you stated it seems very confusing. I thought we were talking about runout and then by injecting stiffness and grain orientation seemed to be confusing. Well at least it seemed to me. But then again sometimes I'm easily confused.

Well I think that would be pretty much a given.

However, the relation between wood with extream examples of runnout(curly) and stiffness has been pretty obvious to me(likely because of just how strong that runnout is). I recognize the grain and runnout would not be the same as runnout in a piece of non figured wood that was not milled parallel to the grain(obviously figured is rising and falling at some interval). It would seem(assumption on my part, I know that sometimes is a bad thing to do) the two would corrilate, but since I am not sure I noted what woods(or types of runnout) I was refering to. I am heading out to the shop in a minute to go do a little testing on a straight grain block and see what I find.

Out of curiosity, how did you go about testing to come to your firm conclusion about runnout not modifying stiffness?

Rich

Sorry for not being clear. I was talking about stiffness in regards to quarter sawn vs. off quarter, not in regards to runout.

_________________
http://www.chassonguitars.com

OK,
Only had time to do a quick test, but here is what I did and what happened. I split and cut two equal sized square sticks. One was split true on two sides and milled referencing those splits. The second was cut with 2" off parallel in 24"(very excessive runnout) in the face. Both were cut true to the visable grain and both were on quarter. I also intentionally mixed them up and did not mark them after cutting to not allow myself to know which was which(I assumed it would be obvious after I pushed them to failure, and it was obvious), after mixing I labled one a and one b. The testing was simple. each piece was supported on round bars at each side with position markers. The test used dead weight dropped through a slot to alighn it each time to avoid mis-positioning.

First test was with a 20lb. dead load. stick "a" deflected 5/32" more than "b". No cracking or sign of failure.

Second test was with 25lb. dead load. Stick "a" failed, splitting at an angle with the grain(this was the one with strong runnout) to one side of the stick. Stick "b" did not fail.

I applied a bit of added pressure to the weight without adding actual weight and was able to snap "b". It split along most of its length.

Not the most sophisticated test, but the result was informative. It was a limited test in that I only tested one piece of wood(split into two sticks). I will repeat the test again when I have time with a few more pieces.

If my understanding of the definition of stiffness is correct. It would be the ability to resist deflection when force is applied without damage. Strength or ultimate strength would be the ability to carry a load without damage or failure. Maybe one of the members who has a better understanding of these definitions could confirm or correct me on that.

Rich

I didn't say anything about runout modifying stiffness. I said strength isn't the same as stiffness and that runout has to do with strength as for bracewood. The topic," is this bracewood o.k.", is a question that I asked 2 weeks ago in a round about way and the subject was given good coverage in the MIMF link . I don't know but talking about curly figure being extreme runout seems to be a bit off subject and may only confuse someone new to this subject of bracewood as the originater of this discussion Mat is as well as I. I'm not disagreeing with you because I don't really know if what you are asking is correct.
Rich you should look over that Discussion as it may answer some of your questions that you just asked. There are examples of testing bracewood in there too. Simple but effective.