Flat or precision ground?

When ordering metal stock online what is the difference of flat ground
stock and precision ground stock? Does precision mean a smoother
surface or something else?
Reply to
good2get2know
Loading thread data ...
It means what it says. Its precision dimensions. Flat ground is just pretty to look at, tolerances +/- 0.005 kind of thing. Precision ground is +/-0.0005 kind of thing.
Steve
Reply to
Steve Taylor
What Steve said, but recently bought a piece of flat ground 52100 from AdmiralSteel.com and instead of 1/8" it's .116" on on end and .118" on the other. Turns out good for me that it's that way actually. ;)
The grinding marks on the 52100 are in the form of swirls BTW.
The thickness is very important to me since I mess with re-placing pocket knife blades and springs and certain odd-ball sizes are needed. I figure I can flat-file about as good as most but somehow even using a micrometer etc the "homemade thickness" just doesn't feel right after the pocket knife is all together. :/
CRA 1095 has a smoother finish than precision-ground O1 IME.
But I've gotten some 3/32" 1095 that's as low as .090", which again worked out great for me. :)
CRA (cold rolled annealed) has a nicer finish than the HR (hot rolled) and is what you'll want if any of the finished knife is going to have some of the original surface left showing.
I recently got some hot rolled annealed 1095 and for me, and my dislike of polished knife blades;) it's going to work out great.
All I -really- care about is-> edge taking and edge holding, ok?
Right here on this NG is where I learned so much about circular saw blade steel. -0186 or "8670-modified"- That stuff has turned out to be great stuff! ...and talk about some odd-ball thicknesses. ;)
Done made quite a bit of use of both those attributes already too. :)
One example is an old clunker 4 bladed scout-knife with a missing spring, turned it into a 3 bladed "cattle knife".
Cattle knife = early 1870's Stockman - early 1890's
"murkin" utility knife is a cross between the you're-a-peein utility and the murkin cattle knife = 1900 and adopted by the Boy Scouts in 1911. -paraphrased from Levine's Guide
So a "scout knife" is like, new-fangled junk, or something. ;)
formatting link
(didn't end up using all that's shown) (I made the butt-spring for the original master blade from 1095)
formatting link
(only replaced those two blades and they are .102" 8670-M) (original double-ended-spring was made by Remington and is .100")
formatting link
(original Remington black jigged phenolic plastic handle slabs) (no brass or nickel-silver in that old 50's knife so I used baling wire and W1 drill rod for pins)
formatting link
(the original blade that I didn't re-heat-treat which leads to a whole nuther thread ;)
Alvin in AZ (knife knut)
Reply to
alvinj

Site Timeline

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.