Tool Talk
Woodworking Forum => Woodworking Forum => Topic started by: jooleyen on July 16, 2014, 01:17:14 PM
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I just got a Disston No 7 dated to around 1875 for about $5 in good condition. I am having a hard time telling whether it's a rip or crosscut saw, as I don't have a crosscut saw to compare it and the teeth are dark with age. It's 10ppi and 20" long.
If it does happen to filed for a rip cut, can I simply file the saw as I would a crosscut and convert it to cross cut that way, or is there more to it than that?
Also, as long as the 6-sided (triangular looking) file is twice as thick on a face as the saw teeth are tall, can it be used? I have a file rated for a 6ppi saw and would use it on this 10ppi if that would be okay.
Thanks from a newbie sawyer
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10 tpi blades are crosscut — rip teeth are more in the 8 or 6 tpi range (he says without going to his shop). Rip teeth are like little chisels, with the chisel-like teeth sharpened perpendicular to the blade and the direction of the wood grain. Crosscut teeth come to a point and are meant to Cut the grain, which runs opposite to the direction of the cutting/sawing. Someone MAY've sharpened rip-style on crosscut teeth, but I dunno why.
As to the file to use, files are usually (always?) longer on a side than the teeth they're used on. I can't say as I've Ever seen a file rated for a particular tpi, but I doubt I've seen everything even yet. *he sighs meaningfully and grins*
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Thanks for the help bear_man. I gave it a go and the small saw was crosscut. Easier to see in good lighting and after taking a stroke with the file.
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There's more than you're likely to need, or even want, to know on this subject here: http://wkfinetools.com/tRestore/saw/sawsRestore-index.asp (http://wkfinetools.com/tRestore/saw/sawsRestore-index.asp). Another good resource is http://www.vintagesaws.com/library/primer/sharp.html (http://www.vintagesaws.com/library/primer/sharp.html).
Rip teeth are more upright:
(http://www.vintagesaws.com/library/primer/ripprofile2.JPG)
than crosscut teeth:
(http://www.vintagesaws.com/library/primer/crossprofile2.JPG)
, in addition to the angles Bear_Man mentions.
And, while handsaw* rip teeth are generally coarser than crosscut teeth - the common rip pattern is 5-1/2 points per inch, while crosscut teeth are generally 10 ppi and up, with the occasional 8 ppi saw - there's no particular reason why some past mechanic might not have wanted a finer rip saw for some application.
*Handsaw being the 20-26" long saws with no stiffening back on them, the kind you find at yard sales everywhere.
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Bill, thanks for weighing in. The second link in particular is quite helpful to newbies on restoring saw teeth, in my estimation. I was running only on memory when I replied…, and I forget why my memory ain't always what it oughtta be. (O:
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I was running only on memory when I replied…, and I forget why my memory ain't always what it oughtta be.
Yeah, I understand the memory is the second thing to go, after some danged thing that I can't remember what it is.