Speaking of abrasive paper.

F

frwillia

Guest
I'm trying to find someplace on line to get a few sheets of abrasive paper in grits from 100 to around 1200. I don't want packs of 50. i don't know of any place locally to find that stuff, though I haven't tried Pague & Fagen yet (the oldest hardware store in PA, or so I'm told, it's been there for about 100 years). Any favorite sources?

I went to smallparts.com to see what they might have. They have an assortment of grits which I'm inclined to buy just to see what they are. See: http://www.smallparts.com/3M-Piece-..._s=center-3&pf_rd_m=AIUBT5HP6PMAF&pf_rd_t=101

The paper is graded in microns. A micron is a millionth of a meter. Assuming for the moment that 30 micron paper has grit spaced 30 microns apart, that would be 30E-06 meters which translates to 0.00118", the reciprocal of that would be 846. Is this right, 30 micron paper is about the same as 846 grit paper?

If so, their 2 micron paper would be something like 12,700 grit! I'd think you could about polish corneas with that. Must have optical uses. Not much use for gunsmithing IMO. But I'm really new at this.

I'd really like to find a source of one or two sheet quantities. I cut off little strips - a couple of sheet would last me a long time.

Fitch
 
I use 3 M imperial wetordry production paper.
It can be purchased at most auto body and paint stores in singles, 5-packs or in bulk.
Grits from 80 to 5000.
Use it wet on metal with mineral sprits.on paint use water.
I seldom need anything finer than 1000.
600 gives a very nice finish to metals that are to be blued.
Glue it down to blocks or rounds of hardwood or metal and use these for polishing as well. Even though it has a paper backing
it will last a long time if you keep it wet.
You can ues it dry but it cloges rapidly.
I have tried other brands but nothing comes close to the 3M product

Chuck.
 
Dave,

Thanks for the good link. Learned a lot from it.

Chuck,

Thanks for the heads up. There is an autobody shop a mile or so from here. I'll stop by and see if they sell the stuff.

Fitch
 
frwillia said:
The paper is graded in microns. A micron is a millionth of a meter. Assuming for the moment that 30 micron paper has grit spaced 30 microns apart, that would be 30E-06 meters which translates to 0.00118", the reciprocal of that would be 846. Is this right, 30 micron paper is about the same as 846 grit paper?

If so, their 2 micron paper would be something like 12,700 grit! I'd think you could about polish corneas with that. Must have optical uses. Not much use for gunsmithing IMO. But I'm really new at this.

Fitch
Click to expand...

Pal, in the civilised World the number of the grit is a number that coresponds to how many MINUTES of time it takes for a specified amount of the abrasive powder (grit) to settle if suspended in the water of a glass cylinder 2 metres tall. If it takes 60 minutes for the abrasive powder to settle it's a 60 grit, if it takes 1200 minutes to settle, it's a 1200 grit and so on. 2000 grit will give you smoother finish than that found on a glass window Rad
 
Rad Mrdal said:
Pal, in the civilised World the number of the grit is a number that coresponds to how many MINUTES of time it takes for a specified amount of the abrasive powder (grit) to settle if suspended in the water of a glass cylinder 2 metres tall. If it takes 60 minutes for the abrasive powder to settle it's a 60 grit, if it takes 1200 minutes to settle, it's a 1200 grit and so on. 2000 grit will give you smoother finish than that found on a glass window Rad
Click to expand...

Easy there John Wayne, for "true grit" you need to know what system the paper maker is using. ;)

The CAMI or ISO, if the prefix is P, the system is an iso paper. Both are made in the civilized world. Many (modern) machinist manuals have the conversion Cami to iso to micron.

what I use..

http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=1664205&PMT4NO=58959031
 
Last edited by a moderator:
Rad Mrdal said:
Pal, in the civilised World the number of the grit is a number that coresponds to how many MINUTES of time it takes for a specified amount of the abrasive powder (grit) to settle if suspended in the water of a glass cylinder 2 metres tall. If it takes 60 minutes for the abrasive powder to settle it's a 60 grit, if it takes 1200 minutes to settle, it's a 1200 grit and so on. 2000 grit will give you smoother finish than that found on a glass window Rad
Click to expand...

That system only works on Earth. NASA had to devise new standards to be used on the Moon and planets other than Earth.
Hint: It involves centrifuges. Sorry, can't say more, Classified.
 
I didn't know about the settling time definition of grit.

I did think I recalled that in the Richard Franklin video he polished the chamber with 1500 grit paper. So I got out the DVD, found that part of it, and sure enough, he wrapped 1500 grit paper around a split dowel and polished the inside of the chamber he had just reamed. He use 400 grit first, then 1500.

I wouldn't use the finer paper just because he does. However, he and his customers have managed to use those chambers successfully while shooting thousands of ground hogs, they weren't having stuck brass or he would have said so, so it didn't seem like it was going to be the kiss of death for the rifle to polish the chamber with something finer than what I used yesterday.

Following up on the suggestion to try automotive body shops or supply stores, I stopped at the body shop closest to where I live - they had no sheets or rolls, only discs. They suggested a place on the other side of town, Advance Auto Parts if it matters, that had small packages of fine grit paper and "sampler" packages with 220, 400, 800, and 1,000 grit 3M paper. So I went to the Auto Parts store and bought the sampler for four bux and change plus tax. Less then 5 bux.

I came back, cut off some strips from the 800 and 1,000 grit sheets, and proceeded to polish the chamber with both of those for a few seconds. It sure is nice and shiny and smooth now. I'll be really interested to see if it makes the brass stick. I don't think it will, but I've been wrong before.

Fitch

PS, if the brass sticks, I'll be back to pass on that bit of data.

frw
 
You must log in or register to reply here.
Back
Top