Thread: Why lapping film rules

I've just been using standard fil for a while, not diamond, and I love the stuff. I got five sheets of each of the two grits I use 5 and 1 micron and am not sure when I'll run out. For the professional honer doing a hundred a week, this isn't going to be the best option, but for a guy with a rotation of a dozen or two it will work for a good long time.

I use my films stuck to glass, the glass mounted to mdf to give it some thickness and durability. I treat the 5 like a 4000K Norton and the 1 Like the 8000, in fact I have used Randys Pyramids as written with good success, though finishing with some extremely light strokes (10 or so) on the 1 makes the shave even smoother. I've also honed progresivly with it and again, with the 5 and 1 micron films, you can treat film very much like the 4/8k combo stone so many are very familiar with.

When I get around to ordering more I will give the diamond a shot, a finer grade too, but I hardly see the reason to worry about it so it could be a while.

If you look at my post #11, you can see that there is quite a bit of slurry type extraneous scratches when using the AlO2 honing film. The diamond is much better bonded, and each grit hones much "cleaner" than the Al02.

The diamond lasts longer, hones cleaner, and costs more. Both are effective. Choose your poison.

With stones I find it is difficult to get a clean edge. I hone down through the usual progression and when I inspect the edge with a 10K loup, there frequently tends to be a slight halo along the edge which I take to mean that the intersection is not clean and burr free. With the diamond film this has never happened. (I can't speak to the AlO2 film since I haven't tried it.)

I would agree that lapping film probably makes more sense for the guy that just sharpens his own razors. You know using a straight is really not that difficult. The main deterent for the average guy is sharpening. The availability of modern synthetic hones has helped with the resurgence of the straight razor. Maybe lapping film could help extend that trend.

Originally Posted by Seraphim

You can hone ceramic on diamond lapping film (ceramic mohs scale-9, diamond mohs scale-10, steel mohs scale ~7.5).

I like your approach and lapping film is waiting in my desk to give it a try.

For the sake of having correct figures for prosperity...
hardened steel is not 7.5 Mohs, according to my sources: eFunda: Convert Hardness: Rockwell C-Scale
On the Rockwell C scale, which is what's generally used for cutlery, HRC 64 = 6 mohs. HRC 58 = 5 mohs. Both are exponential scales, so the differences between one point and the next are rather huge.

One thing that's not clear to me: how do I keep the film from not moving around when the sheet of paper sits between the tile and the film. I understand that the film sticks to the tile with a bit of water (air bubbles to be avoided). But how do I keep it stuck with the paper sheet in between?

Thanks,
Bart.

I have been using lapping films from the start. I have found them to very effective and quite easy to use.

Now after a year or so of doing my own honing and having honed about 50 razors this last year, I have two different honing progressions. One involves films and one does not.

BUT if I am setting a bevel I like the bevel off of 30 micron film better than a stone hone. It is so clean and for me it always does the trick.

Progression #1:
a) 30 micron lapping film (not diamond) until the bevel is clean and even and nicely passes the TNT.
b) #3000 Chosera (Naniwa) usually 30~50 there and back strokes.
c) #5000 Chosera (naniwa) ussally 30~50 there and back strokes.
d) 1 micron lapping film (not diamond) 30~50 there and back strokes.
e) 0.5 micron lapping film (not diamond) 30~50 there and back strokes.
f) 0.3 micron lapping film (not diamond) 30~50 there and back strokes.
g) 100 on latigo
h) 100 on horsehide

Note I don't always include step 'd'. If I am out of 1 micron film I can usually do a few very light strokes on the #5000 and get the same finish on the edge.

Progression 2:
a) 30 micron lapping film (not diamond) until the bevel is clean and even and nicely passes the TNT.
b) #3000 Chosera (Naniwa) usually 30~50 there and back strokes.
c) #5000 Chosera (naniwa) ussally 30~50 there and back strokes.
d) Coticule #1 (La Petite Blanche fast cutting) 30~50 there and back strokes.
e) Coticule #2 (La Petite Blanche Vintage, finer than the previous coticule) 30~50 there and back strokes.
f) Cromium Oxide balsa bench hone 30~50 there and back strokes.
g) 100 on latigo
h) 100 on horsehide

To be honest I like both but prefer the coticule method. But if I am going to sell a razor I use progression #1. The edge is extrememly keen and super smooth. Almost too sharp. But I like to keep my reputation consistent when selling a shave ready razor.

I have done a complete lapping film progression in the past and liked it but since I got the Chosera #3000 and #5000 my edges are still great and eliminate #15 micron, 5 micron and sometimes the 1 micron as well.

I keep my Chosera hones lapped so I can use them as a base for my lapping films. I cut them the same size as the chosera and use clean water to stick the film to the hone top (note the film I use is not the adhesive type). The only time I find that the film moves around a bit is the final two 0.5 and 0.3 micron film. The razor suction on these two is quite strong. In this case a firm finger on a corner of the film prevents any drastic movement of the film.

On another note I have seen mentioned that Bill Ellis also incorporates lapping film into his honing progression (FYI only).

I use lapping film as well. I have a SEVERE HAD disorder though.

I have a pretty good source for it I'll post it later, its saved on a different computer.

Originally Posted by Bart

I like your approach and lapping film is waiting in my desk to give it a try.

For the sake of having correct figures for prosperity...
hardened steel is not 7.5 Mohs, according to my sources: eFunda: Convert Hardness: Rockwell C-Scale
On the Rockwell C scale, which is what's generally used for cutlery, HRC 64 = 6 mohs. HRC 58 = 5 mohs. Both are exponential scales, so the differences between one point and the next are rather huge.

One thing that's not clear to me: how do I keep the film from not moving around when the sheet of paper sits between the tile and the film. I understand that the film sticks to the tile with a bit of water (air bubbles to be avoided). But how do I keep it stuck with the paper sheet in between?

Thanks,
Bart.

Thanks for the Mohs clarification. I had simply found "hardened tool steel" or something listed as Mohs 7.5, and thought that would describe razor steel.


You use the paper by first putting water on your honing substrate, lay down the paper, let it absorb the water, be sure to remove all wrinkles, then lay down the film on top of the wetted out paper. It sticks even more solidly than just the film on the substrate directly.



P.S.--as an aside, it turns out I haven't even used lapping film the last couple of months. I've been using DMT plates (600, 1200, 8000) finishing on ChromOx.

I have to re-order some diamond film!

Originally Posted by Visibility

I have a pretty good source for it I'll post it later, its saved on a different computer.

I'll be waiting!! I need some more to play with!!

I can't find it? I have this site but they don't have the film...or at least I can't find it.

Diamond Suspension, Diamond Compound and Polishing Pads for polishing samples - Kemet UK

I'll keep looking.

Originally Posted by Seraphim

P.S.--as an aside, it turns out I haven't even used lapping film the last couple of months. I've been using DMT plates (600, 1200, 8000) finishing on ChromOx.

I have to re-order some diamond film!

The online sources that I found are very expensive for a disposable item. Where do you get yours?