Sandpaper question

[Matthew N. Masail]

are Zirconia sandpapers as good on wood as Aluminum oxide? is there a reason I would want Aluminum Oxide over Zirconia?

what grit PSA roll is best for re-establishing plane iron bevels?

[Jim Koepke]

Not sure it is the best for re-establishing bevels, but I have been using 80 grit on a large (4 foot) hunk of granite to establish bevels on really badly messed up blades. Haven't used it in a while. It is usually only needed when a blade is bought used.

Another part of my sharpening system is the Veritas Mk.II power sharpening system that also uses 80 gritt for the coarse grinding plate.

jtk

[Andrew Pitonyak]

Aluminum oxide is one of the best all-purpose sandpapers for wood working. Aluminum oxide has a very tough block shaped grit that fragments under heat and pressure. The friability exposes new cutting edges.

Zirconia is very very hard; pretty close to diamond (step or two away on the hardness scale I think). Zirconia requires extreme pressure to fracture, so by itself I would expect it would not be good for wood; I think that it is usually used to shape metal. I expect that on sandpaper, it is probably Alumina Zirconia, which is a combination of Zirconia and Aluminum Oxide, which will increase friability.

I expect that the Zirconia sandpaper that you have is a mix and that it will stay sharp a long time. Most seem to target metal because it holds up, but I expect that it will work on wood just fine, because most list wood as a supported application. In the right mix, I expect that this will last longer then Aluminum Oxide on its own, but do not have practical experience to prove or disprove the statement.

The Zirconia might be better for establishing bevels because it is typically marketed specifically for metals. As for establishing bevels, 80 grit is very aggressive and I expect a few minutes by hand and you would have it. Off hand, I would guess that 80 / 120 / 320 / 600 / 1000 / 2000 would be a nice progression (if you want to go that high).

[Sean Hughto]

Here in the Neanderthal forum, we only use seal skin, shark skin, or dutch reeds as our wood abraives. Sheesh.

[Andrew Pitonyak]

Here in the Neanderthal forum, we only use seal skin, shark skin, or dutch reeds as our wood abraives. Sheesh.

And here I have been using my own callouses all these years....

[Matthew N. Masail]

Thanks Andrew! that helps a lot

[Rich Engelhardt]

are Zirconia sandpapers as good on wood as Aluminum oxide? is there a reason I would want Aluminum Oxide over Zirconia?
Garnet - the reddish/brown stuff - is better than Aluminum Oxide for sanding wood from the perspective of leaving a smoother finish.

Aluminum Oxide is tougher and lasts longer, which makes it more economical to use in the long run.

Garnet paper is a bit difficult to find these days. Most stores only stock Aluminum Oxide and Silicone Carbide (wet/dry).

[Matthew N. Masail]

this place http://www.supergrit.com/products/products_rolldrumsleeve-psa.asp stocks EVERYTHING. it's amazing. the garnet sheets are actually really well priced. but for now I need 4X36 belts to grind down HSS and other hardened metal blades for tool making.
I think I'll try a Ziriconia, a Ceramic belt and SC one, otherwise I'll never know what works best. once I'm buying I'll get some other giddies (-: but I gotta be careful as I could easily leave 400$ there... by budget is 60 )-:

[george wilson]

I only use zirconia blue belts for grinding steel. Infinitely better than the older alum.oxide brown belts. They cost more,but cut better and last longer.

[Matthew N. Masail]

Thanks George! which grits do you recommend? first task is the grind a HSS blade to be 2mm narrower.

[Sam Takeuchi]

Wait, you want to grind a HSS blade 2mm narrower with abrasive papers? As in reducing width?

[Jim Koepke]

this place http://www.supergrit.com/products/pr...sleeve-psa.asp stocks EVERYTHING.

I have been happy buying from them in the past.

I don't know about them having everything, but they do carry a wide selection.

I think most of their items are from closeouts and such so the inventory changes some.

I do not use as much sand paper on wood as I used to since planes leave a pretty smooth surface.

jtk

[Matthew N. Masail]

Wait, you want to grind a HSS blade 2mm narrower with abrasive papers? As in reducing width?

yep.... how else do you suppose to do it? I know it will take some time, but I'm holping the right belt will work well.

[Matthew N. Masail]

I have been happy buying from them in the past.

I don't know about them having everything, but they do carry a wide selection.

I think most of their items are from closeouts and such so the inventory changes some.

I do not use as much sand paper on wood as I used to since planes leave a pretty smooth surface.

jtk

Well over here I can barely find 4X36 inch belts, unless I call a specialist store. the chances of finding Ziriconia isn't even worth my energy, so for me, they do have everything (-:

I much prefer a planed surface to a sanded one too, but I can't plane steel.... and I find the belt sander very convenient for little wood pieces in awkward shapes

[Sam Takeuchi]

If you have a belt sander, belt grinder or dry grinder, they should work ok with right abrasive, but if I were in your position, I would go for a dry grinder. Grinding M2 is a major chore and it'll cause major wear and tear on the abrasives. I'm not sure how much abrasive papers are able to hold out before being worn out. 2mm (that is 0.079" for you non metric folks) is a big chunk of metal to remove.

If you are going to be grinding hardened HSS, I wish you best of luck (truly and sincerely, because it'll suck, as I have a few HSS blades I regularly work with and grinding them is really slow, boring and require patience). But at least you can go aggressively without fear of drawing temper, if there is anything good in that.

[Matthew N. Masail]

Thanks Sam, I guess it is quite of a chore. I've grinded 1mm of a carbon steel blade, took a while, but I was using a worn out aluminum oxide belt, I imagine a new Zirconia would be a world apart. I haven’t ground HSS yet... I hope it's not as hard as you predict. I'll keep you posted once I give it a shot.