The back story is below, but to cut to the chase, I’m looking for suggestions on a good lapping film progression for the PSA Lapping Film grits that I have. I don’t want to spend excess time stepping up in small increments, but I also don’t want to short change myself (i.e., I don’t want to over or under hone), nor do I want to purchase more tile than I can reuse (i.e., for a balsa progression) once I use up the PSA film I have. A photo of the grits I have is below, but currently I’ve been using the 30u to bevel set and then moving sequentially up from there (12u, 9u, 3u, 1u and sometimes to the .3u w/paper underneath). I’ve tried using the 12u for bevel setting, but it didn’t seem to cut as efficiently as the 30u or 1000 grit wet/dry, but I don’t know if the 30u is too aggressive for general use. Inputs would be greatly appreciated and you can stop reading now unless you’re a fan of slow motion train wrecks below.
BACK STORY -- The PSA film is not what I intended to get, and while it sticks and stays really flat, it’s not interchangeable like non-PSA (lesson learned), but now I’m stuck and looking for a path out. I first purchased a variety pack of non-PSA lapping film and one piece of ~4x12” marble tile at Home Depot. Unfortunately the film was put into a plain paper envelope (non-rigid or padded) and sent through the USPS (i.e., they ran it over with a bulldozer before sending it through their mail handling department and then rolling, folding and then stuffing it into my mailbox). As a result, the film was creased and pockmarked with all sorts of small impact marks to the point that while the film will adhere (mostly) to the marble with water, it’s unusable as it’s nowhere near flat. So I ordered another variety pack of lapping film (from another vender), and upon receipt discovered I mistakenly ordered PSA backed lapping film. Additionally, Amazon sent two identical packs of film (in plain, unpadded envelopes, i.e., damaged) and wanted one back (I opened both and pieced together one undamaged set). Not wanting to deal w/Amazon any longer, I cut pieces to fit the marble, and once adhered, it worked great, nice and flat and absolutely no movement/shifting under use for every grit I tried. I discovered that you can remove the film and move up in progression like non-PSA film, but it’s really “one and done.” Removing the film once applied causes the adhesive to wrinkle and while it will re-adhere to the marble tile, it’s nowhere near flat and usable. I was able to remove the wrinkled adhesive backing with fingernail polish and a cotton ball, allowing the film to adhere w/water like the non-PSA backed sheets. Unfortunately I think either: the PSA backed film is thinner than non-PSA sheets, and or the acetone affected the backing film because some of the sheets have begun to curl at the long edges and not stay flat on the tile; hurting the quality of my edges especially where the film begins to curl (I think they can be better). Long story too long, I’ve been able to use the first set of PSA backed film with the adhesive removed, but they’re curling is becoming unusable (trying to take the curl out with an iron doesn’t work either). I want to use up the PSA film, so I’m looking to buy the right number of tile pieces to get the job done (not over or under hone) as tile is cheaper than another pack of film and it can be reused as backing material for an eventual balsa progression. Any ideas or suggestions are much appreciated.
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BACK STORY -- The PSA film is not what I intended to get, and while it sticks and stays really flat, it’s not interchangeable like non-PSA (lesson learned), but now I’m stuck and looking for a path out. I first purchased a variety pack of non-PSA lapping film and one piece of ~4x12” marble tile at Home Depot. Unfortunately the film was put into a plain paper envelope (non-rigid or padded) and sent through the USPS (i.e., they ran it over with a bulldozer before sending it through their mail handling department and then rolling, folding and then stuffing it into my mailbox). As a result, the film was creased and pockmarked with all sorts of small impact marks to the point that while the film will adhere (mostly) to the marble with water, it’s unusable as it’s nowhere near flat. So I ordered another variety pack of lapping film (from another vender), and upon receipt discovered I mistakenly ordered PSA backed lapping film. Additionally, Amazon sent two identical packs of film (in plain, unpadded envelopes, i.e., damaged) and wanted one back (I opened both and pieced together one undamaged set). Not wanting to deal w/Amazon any longer, I cut pieces to fit the marble, and once adhered, it worked great, nice and flat and absolutely no movement/shifting under use for every grit I tried. I discovered that you can remove the film and move up in progression like non-PSA film, but it’s really “one and done.” Removing the film once applied causes the adhesive to wrinkle and while it will re-adhere to the marble tile, it’s nowhere near flat and usable. I was able to remove the wrinkled adhesive backing with fingernail polish and a cotton ball, allowing the film to adhere w/water like the non-PSA backed sheets. Unfortunately I think either: the PSA backed film is thinner than non-PSA sheets, and or the acetone affected the backing film because some of the sheets have begun to curl at the long edges and not stay flat on the tile; hurting the quality of my edges especially where the film begins to curl (I think they can be better). Long story too long, I’ve been able to use the first set of PSA backed film with the adhesive removed, but they’re curling is becoming unusable (trying to take the curl out with an iron doesn’t work either). I want to use up the PSA film, so I’m looking to buy the right number of tile pieces to get the job done (not over or under hone) as tile is cheaper than another pack of film and it can be reused as backing material for an eventual balsa progression. Any ideas or suggestions are much appreciated.
View attachment 1392103
