Straight edges on sale

I ordered a 36" one about two weeks ago. Even though they say "in stock" on the website, they're backordered. I just got an email today saying the expected ship date is now 24 January.

They seem like a good deal. Not as accurate as the Starrett, but less than half the Starrett price, too.

At 0.0005" per inch (maximum error) across 36", it could be as much as 0.018", or about 1/55". Probably close enough for anything in the woodshop, but certainly not for a machinist.
 
Funny how they manipulate the numbers to make you think they are far more accurate then what they are. Still I suspect they are more accurate then that. .018 is a long ways. That is you can easily see that difference with the naked eye. I don't think they will be an issue for anyone involved in woodworking, except maybe for setting up the knives on a jointer or something.
 
Funny how they manipulate the numbers to make you think they are far more accurate then what they are. Still I suspect they are more accurate then that. .018 is a long ways. That is you can easily see that difference with the naked eye. I don't think they will be an issue for anyone involved in woodworking, except maybe for setting up the knives on a jointer or something.

Yep, I noticed that also, Travis. .018 sounds like something that you used to set your lawnmower points. I generally use my 12 or 24 inch Starrett combo squares, or my Starrett T-square. But when things get tough, I get out the 36" Starrett straight edge.
 
Yep, I noticed that also, Travis. .018 sounds like something that you used to set your lawnmower points. I generally use my 12 or 24 inch Starrett combo squares, or my Starrett T-square. But when things get tough, I get out the 36" Starrett straight edge.

I checked the Starrett site, and they show their straightedges as being accurate to 0.0002" per inch, so the difference is that instead of a max error of 0.018 over three feet, you'd only have a max of 0.0072".

Those are worst case examples, BTW. In acruality, if one segment is actuall max error in one direction (+0.005) and another section is off in the other direction (-0.005), who knows what you might end up with. It'd be less than maximum error, but still off one way or another...
 
Jim, I guess we are just getting to precise for our own good.:huh: I don't know what a machinist would say, but an edge that varies by a small number of 10ths of a thousandth is just fine with me.:thumb:

I remember a college physics professor mentioning that in subatomic physics this was a cross-section measure called a 'barn'. I looked it on on google just now and a barn is an area of 10**-24 sq. cm. For atomic physics, that is "big as a barn," and hitting it is like hitting the broad side of a barn.:)
I guess it is all relative to what we are doing. In most cases, I am happy with something in the 1/64" range.
 
I say if one needs better than 18 thou for woodworking, you're starting to become a wood machinist. Metalheads will scream over that, but for wood I doubt the thickness of my dovetail saw blade will make that much of a difference...but that's me. And BTW, Starrett tools are used by machinists...so that accuracy is certainly needed (if you work with metal:p).

EDIT: getting any of my work within .018" is something I look forward to...:D

I agree. See my first post in this thread. The one you quoted is just a follow-up to other's comments.
 
In most cases, I am happy with something in the 1/64" range.

Wow, that's only .015 of an inch, right at the see-it-with-the-naked-eye range.

The carpenters at work have some of the tightest tolerances I have ever seen as far as woodworking goes and they accept 1/32 and ½º. I think that is just about right.

At work, I look at something and if I feel like I should ask the boss if its okay or not..well I know its not. If you have to ask, then re-do it is my motto. Some of that follows me home too, but it reaches a point when woodworking no longer becomes fun too. Its been a long time since I made anything in my shop (my house addition sucked up my time) but generally I like to make unique, one-off kinds of stuff. In that way the uniqueness of the project kind of outweighs any minor imperfections like if a dovetail joint has .022 gap in it. Its funny because most of mine do, but I have yet to have anyone say ..."did you know you have a .022 gap in your dovetail joint right there?":D
 
Travis, I can shoot for 1/64 and rejoice if and when I hit it.!:eek: Most of the time I just use the 1/32 marks on the Incra fence system.:thumb:
 
Travis, I can shoot for 1/64 and rejoice if and when I hit it.!:eek: Most of the time I just use the 1/32 marks on the Incra fence system.:thumb:

I'm new to this forum but thought I'd add my .02 cents worth. I can't tell the difference on a rule between two adjacent 64ths markings, so what do I care? I do well to differentiate 32nds graduations and that's with my reading glasses. I agree that striving for accuracy is a good thing, but like another poster mentioned - trying to become too precise takes the fun out of woodworking.

JimC
 
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