Thread: Why lapping film rules

OK, so why is lapping film any better than a hone?

Flexibility.

Here is the edge coming off of the 0.3um aluminum oxide film, laid flat on the precision granite plate:



Not bad (I did not spend a whole lot of time on that edge...)


But then I put the magic of lapping film to work---I put a single sheet of plain paper under the lapping film, which adds some cushion, and give it a few passes....


Much better!

I've played around with mulitiple sheets under there, which leads to a stronger convexing of the edge, but a single sheet on the finishing grit seems to give the best results.

Viva la Film!

WOW! How silky smooth is the shave off that blade?
Do you find the films to be more effective, or more accuratley, the difference between a hone and films greater, on differetn types of steels?

Is there someplace where you have outlined the whole system? Is there someplace the whole system is available to purchase? What is this "precision granite" you refer to?

Do you still use CrOx or other pastes after? Doesn't seem like you'd need to!

Wow. That's a lot of quesitons, but if I could get an endge like that....I sure want to try!

Originally Posted by smokelaw1

WOW! How silky smooth is the shave off that blade?
Do you find the films to be more effective, or more accuratley, the difference between a hone and films greater, on differetn types of steels?

Is there someplace where you have outlined the whole system? Is there someplace the whole system is available to purchase? What is this "precision granite" you refer to?

Do you still use CrOx or other pastes after? Doesn't seem like you'd need to!

Wow. That's a lot of quesitons, but if I could get an endge like that....I sure want to try!

Diamond lapping film is the most effective hone on the planet (OK, DMT diamond plates are probably just as effective, but not as velvety smooth feeling...). If anybody is crying about how stainless is too hard to hone, so-and-so's razors are so super-hard they are impossible to hone....etc. That is just because they are using ineffective hones! You can hone ceramic on diamond lapping film (ceramic mohs scale-9, diamond mohs scale-10, steel mohs scale ~7.5).

Precision granite plate is available from Woodcraft, or you can simply use a thick piece of glass.

Do a search for "lapping film" there are some good tutorials out there already.

I haven't tried diamond lapping film, but I tried the alminum oxide film (gift from one fine Seraphim). I found it great at sharpening a couple edges that I had trouble with on hone (a big wedge and a le grelot). I didn't find the edge as comfy as I do off my coticule or escher, but could get there with a TON of latigo stropping. But the films seem to combine the efficacy of a pasted strop but the mechanical soundness of honing edge first. Maybe diamond film would be silkier, but for me the film is a weapon to deployed when I'm struggling, but if I'm winning iwth a hone I like the fell off the coticule better.

Originally Posted by loueedacat

I haven't tried diamond lapping film, but I tried the alminum oxide film (gift from one fine Seraphim). I found it great at sharpening a couple edges that I had trouble with on hone (a big wedge and a le grelot). I didn't find the edge as comfy as I do off my coticule or escher, but could get there with a TON of latigo stropping. But the films seem to combine the efficacy of a pasted strop but the mechanical soundness of honing edge first. Maybe diamond film would be silkier, but for me the film is a weapon to deployed when I'm struggling, but if I'm winning iwth a hone I like the fell off the coticule better.

try thr single sheet of paper under the final film (you have to be sure to remove all wrinkles from the paper before honing!).

Also, 0.3um may be a bit too fine. stopping at 1um may make the edge feel a bit more comfortable.

Those results are truly amazing!

The striations in the second picture are remarkable smoother and finer.

I suppose comparing the first picture to the second would be similar to comparing a razor honing (on a stone) with more pressure vs. virtually no pressure. The paper as a cushion eleviated some of that pressure....truly amazing, since it's only a single piece of paper!! Just goes to show how sensitive the metal can be to the slightest changes.

Thanks for sharing!

Seraphim
i am talking about 1 st picture ,the reslut of blade comes out from which stone?what have you use for final edge?i think you don't have right final edge stone or you have not using your stones right way?Your edge shouldn't look like that after your last final edge stone.that picture looks like come out from 4k.
Now i don't have what type microscope you have. i have only 100x and talking about knowledge from 100x microscope level.
Do you have Escher, Nakayama ?etc
Sorry Belgian confuses me .

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.