barryjyoung
Member
I want to just say a few things and ask a couple of questions. Hope I don't annoy.
Delrin is a brand name owned by DuPont for their products made of Acetal material. It is quite dense yet easily worked with very sharp milling cutters. It is slick and smooth and would be ideal for darkslides for film holders except for two things. It is hard or impossible to find in sheets .050 thick which is how thick Korona darkslides are, and it is not rigid enough in thin sections over the length required for a 7x17 holder. In my opinion. However, unlike ABS or PVC, Acetal does not seem to attract dust like a magnet which many people overlook when trying to find darkslide and septum material. So, if you are willing to have floppy darkslides and if you think it will fit in your Korona holders (I do not believe a .062 sheet will fit into a Korona light trap and it does not in mine), then have at it with Acetal sheets. By the way, removing that .012 excess thickness,,,,you don't even want to go there.
Jason: I believe the septums in our Korona film holders are made from a material called believe it or not "fish paper" which is used in the electronics industry as an insulator. It ranges in price from $350 to $400 per 48x96 sheet. Ouch! I think a better material is what the original Korona dark slides were made of which seems to be Vulcanized Fiber in four laminations .010 thick joined with an adhesive only along the periphery of the piece. I do not know why, but that is how it is. The darkslides are .050 thick. The septum is also .050 thick. Please toss corrections at me if I made an error here folks.
I will be obtaining some of this material and would be happy to furnish enough to you for your needs at my cost if you are interested. I can also offer you darkslides with wooden handles attached and a septum made to fit if you are interested in bypassing all the work all together. You see, I have already bought and am awaiting delivery of the tooling required to manufacture 7x17 Korona pattern film holders commercially. I expect with CNC capabilities that I will be able to offer double light trap 7x17 holders for something less than $300 each which is a significant savings over available holders.
Now for my question. Though I have a viable design for light trap, does anybody know where I can buy the brass comb used in the light traps of better quality film holders? I would like to make a world class product and frankly without the brass comb, these holders will have to compete on price point alone.
Thanks, hope I didn't ruffle any feathers, especially with the other holder manufacturers.
Delrin is a brand name owned by DuPont for their products made of Acetal material. It is quite dense yet easily worked with very sharp milling cutters. It is slick and smooth and would be ideal for darkslides for film holders except for two things. It is hard or impossible to find in sheets .050 thick which is how thick Korona darkslides are, and it is not rigid enough in thin sections over the length required for a 7x17 holder. In my opinion. However, unlike ABS or PVC, Acetal does not seem to attract dust like a magnet which many people overlook when trying to find darkslide and septum material. So, if you are willing to have floppy darkslides and if you think it will fit in your Korona holders (I do not believe a .062 sheet will fit into a Korona light trap and it does not in mine), then have at it with Acetal sheets. By the way, removing that .012 excess thickness,,,,you don't even want to go there.
Jason: I believe the septums in our Korona film holders are made from a material called believe it or not "fish paper" which is used in the electronics industry as an insulator. It ranges in price from $350 to $400 per 48x96 sheet. Ouch! I think a better material is what the original Korona dark slides were made of which seems to be Vulcanized Fiber in four laminations .010 thick joined with an adhesive only along the periphery of the piece. I do not know why, but that is how it is. The darkslides are .050 thick. The septum is also .050 thick. Please toss corrections at me if I made an error here folks.
I will be obtaining some of this material and would be happy to furnish enough to you for your needs at my cost if you are interested. I can also offer you darkslides with wooden handles attached and a septum made to fit if you are interested in bypassing all the work all together. You see, I have already bought and am awaiting delivery of the tooling required to manufacture 7x17 Korona pattern film holders commercially. I expect with CNC capabilities that I will be able to offer double light trap 7x17 holders for something less than $300 each which is a significant savings over available holders.
Now for my question. Though I have a viable design for light trap, does anybody know where I can buy the brass comb used in the light traps of better quality film holders? I would like to make a world class product and frankly without the brass comb, these holders will have to compete on price point alone.
Thanks, hope I didn't ruffle any feathers, especially with the other holder manufacturers.