Thread: Why lapping film rules

i have read a bunch about lapping film but where can i get it?? and are there some grits you just shouldn't use?

Originally Posted by BenjamanBarker

i have read a bunch about lapping film but where can i get it?? and are there some grits you just shouldn't use?

Here in Canada I've purchased some at Lee Valley Tools.

Try r.s. hughes
286x=.3 micron, 265x= 1 micron, 266x=3 micron

they have lots of cosrser stuff too.

McMaster-Carr carries the film.

I would only add that one needs to go 0.1micron film. I found that 1.0 left a very "toothy" edge that would cause some nasty slices and was very unforgiving . If you are going to stick with films try 0.1 CBN for a final polishing. You might then not need the 0.1 film...just a thought.

Take care,
R

Originally Posted by Sonofabarber

McMaster-Carr carries the film.

McMaster $35 / sheet? Is this correct or are there several sheets in a package? Amazon has 6 sheets for $8, but the darn page doesn't list the grits.

It looks like you have to buy a whole case at rs Hughes

Originally Posted by Crotalus

McMaster $35 / sheet? Is this correct or are there several sheets in a package? Amazon has 6 sheets for $8, but the darn page doesn't list the grits.

It looks like you have to buy a whole case at rs Hughes

Nope. They DO sell single sheets. RS Hughes is a vendor of single sheet 3M lapping film at Amazon. It's where I got my 1.0um and 0.3um AlOx sheets.

Ok, their Amazon listing stinks. They tell you there are 6 grades in a pack, but nowhere do they tell you what grades you are getting.

To my disappointment they stop at 1um. I'll use them, but I just bought .5 and .1 from Lee Valley which is quite a bit more expensive.

but I just bought .5 and .1 from Lee Valley which is quite a bit more expensive

That's the reason why it stops at 1µm. The 0.5µm und 0.1µm are a little more expensive.
It sucks that they did not tell you what grits you would get

But since the 0.5 and 0.1 will be used only for a couple of very light strokes for the finish, they will last you a long time.
Btw. I just finished over 20 razors in a row on the Al2O3 lapping film without a replacement.
I used a 5µm for setting the bevel and jumepd directly to 1µm for the finish. Perfect!
And even after 20+ razors, there is no sign of extensive wear. It seems they still got a lot of life left in them.

Here is a recommendation for you. Try using the lapping film with just a hint of dish soap in the water.
It prevents lutos effect (especially a on the 1µm film) and it helps to wash out steel swarf from between the abrasive particles of the film.
I think this helps make them last longer

Well, you sent me on a web adventure trying to figure out what the heck lutos effect was.