Thread: Float Glass Lapping Film Plates at Lowes

Lowes is now selling Lapping Film Float Glass plates.

Just under 3 in X 12 in X 1/4 in plates, found in the tile section.

They are not dead flat as often said of float glass, but a 325 or 600 DMT will get it flat in a few minutes. They also leave a hazy finish on the high spots that hold the film much better. You don’t have to get the plate completely flat, just mostly.
Cost, 2.57. I bought 4, one for each grit of film I use.

They come in white and a tan color. Buy at least one in the Tan color as the white matches the white of the 1um film exactly… and if you’re not paying close attention and you lighting is not all that bright you may start your stroke off the film on the glass and you will strike the razor edge on the edge of the film.

At 1um you will ruin your edge. White film on a tan glass plate prevents this problem.

Film works well on hard steel razors and produces a fine super straight edge quickly.

Has anyone tried lapping film to polish a natural hone? I have used a DMT to flatten a variety of hones and use W/D sandpaper to 1.5K or 2K grit. I am wondering if this would be a viable alternative or just taking it a bit to far

Thanks for the heads-up on these, I picked some up today. I would recommend bringing along a straightedge or something you know is flat before picking any up though. I bought 3 and 2 of them are so far out of flat it would take an hour to flatten them. The other one lapped in flat in about 5 minutes with a DiaFlat. I'm going to return the nasty ones and bring my straightedge back for some replacements. I also spotted some black granite tile that's about 1/2" thick and sold in 12" square for $4.99 a tile. Grabbed two of those and they are much closer to flat than the glass. I'm going to cut them into ~4" x12" slices with my diamond chop saw and try them out.

I have found you don't need to bring any thing with you to Lowes or any other hardware store ,, they have everything you need right there ,, I use there tape measures and levels and squares ,, makes for an easy day choosing things ,,, try it saves carrying your own! tc

Originally Posted by tcrideshd

I have found you don't need to bring any thing with you to Lowes or any other hardware store ,, they have everything you need right there ,, I use there tape measures and levels and squares ,, makes for an easy day choosing things ,,, try it saves carrying your own! tc

Haha, I highly doubt they have any straightedges that are good to less than .001" - like my Starrett. They probably haven't got anything anywhere near it. Personally I would rather bring my own tools so I don't have to go wandering around the huge store trying to find what I need, but YMMV, TEHO.

BTW the granite tile is also varied in flatness, but I only grabbed two of those. The worse one is about .005" out of flat and the better one is about .002". It's much flatter than the glass tile though. The tile is very very close to flat and even, where the glass is much more uneven and irregular. I also noticed cracks in one of the granite tiles that were not easy to casually notice, so if anyone else tries these out, watch out for those.

Lapping a plate perfectly flat is not critical. For a long time I used an un-lapped fairly flat ceramic tile. You could clearly see wear on the film where it was not making complete contact, yet I was able to get great edges.

I lapped the Ceramic tiles flat with a 325 DMT easily.

The glass plates also are easily lapped with a DMT and while flatness or lack of, may not greatly affect the honing edge performance, it will make the film more efficient buy using all of the grit on the film.

You can also increase film life by rotating your film or plate 180 degrees.

Lapping a plate perfectly flat is not critical

Well, there's a necessary addendum to that statement..."when honing a straight razor." For other, more rigid tools, like chisels and knives, it is critical IMO to get as flat a surface as possible. A razor is very thin steel and will flex/conform to slight irregularities; a knife or chisel will not. For myself, I prefer to get my backing plates - and indeed, even my stones - as flat as possible, since I use them for all of these types of tools and more.

I use the cheap/broken travertine tiles from Lowes off of the discount rack. They cut easy and polish down flat quickly.