So what started as a low cost work around when I started has increasingly become part of standard sharpening progression. Being a family guy on a tight budget I’m always looking for the easier softer(cheaper) way. Innovation on a budget is kinda my mantra…
Previously I kept my sandpaper and AlO2 lapping film in sheets, and cut strips to size as I went but I found the process tedious and wasnt happy with possibly contaminates getting in the stack of paper.
Recently on a solo mission to Wally World I found this small Plano tackle box for $6 while lingering in the knife isle. They had a similar box for $4 each, but the latches where inferior so I splurged.
I could tell just by looking that it would fit lapping film strips perfect(and possibly strops?). While I was there I got the cheapo paper slicer for $9 as well. Then today made a quick trip by the auto body refinishing shop, came home and started chopping!
This box will house p1500, p2000, p2500, & 3000 grit paper strips, maybe a couple more later. I also have a second box laid out with 12u, 9u, 6u, 3u, 1u, & .3u lapping films.
As it turns out the box also perfectly fit 3 pairs of strops in their own separate contaminate free cubicles so I will be getting one more for those as well. There’s something very satisfying about the idea of having identical & inexpensive yet solid cases to cleanly store separately the final stages of the progression so I definitely wanted to share and for the newcomers that may be on a budget such as myself.
Lastly for those interested here is a shot of the 3000 grit paper I picked up today. Of interest is the packaging which shows that it is a “unigrit”. I havent tested this one yet…
Im pretty sure at some point the auto sandpaper and 3m lapping films cover the same ground. I dont have my Universally complex grit chart here handy…
Ordered 9um & 5um lapping films today, one in AlO2 like the others and the 5um in Silicon Carbide just to see. Also kinda excited, ordered a .1um CBN emulsion from Ken Swartz. I have some testing to do with a prototype felt stropping paddle.
Neat. But I’ve got one up on you in the “cheaper” department. I keep my sand paper and lapping film strips in individual 3 5/8 x 6 1/2 envelopes!!! Then again, my WE sharpeners and supplies never leave my work bench … so work and storage space is at a premium.
I started using film a year or two before it became popular here. At the very beginning I felt that I’d need a pair of platens for each pair of grits, so that I could get the most useful life out of each strip. Changing film more often than necessary doesn’t make sense to me as it opens a door for contamination and other problems. I also intended to omit the use of strops in favor of film. So now I have four pairs of platens to cover eight grits: 15, 9, 6, 3, 1.5, 1.0, 0.5 and 0.1 microns. The equivalent grits work out to be respectively 1.2K. 1.8K, 3K, 8K, 13K, 15K, 50K and 100K.
I never use anything other than diamond PSA film and am very pleased with the number of knives sharpened with each film. I have to admit that a film’s usefulness is almost always shortened by contamination or careless cuts when used edge-leading. In the past, I’ve used my Superaser to clean off metal particle accumulation, but I suspect that might have been adding to my contamination problems. I’ve recently taken Clay’s advice and switched to using alcohol as a cleaning agent. Works well. I wouldn’t be surprised if the useful life of diamond film is close to twenty knives, assuming no other reason for changing out.
When using any film-on-platen, it’s crucial to clean the platen meticulously before applying the tape. I stretch the tape as I apply it, so as to avoid bubbles and achieve a very flat surface. Any point which stands proud of the face will be sliced off with the first edge-leading stroke.
Early on, it was difficult to find diamond PSA films, so I started out with Aluminum Oxide. After some use, I could see areas on the surface where the abrasive grit was completely gone. All that remained was the gloss of the Mylar substrate. I don’t think I’ve ever seen that with diamond film.
