Re: Question about DECtape formulation
> On Jan 25, 2022, at 1:13 AM, Chuck Guzis via cctalk > wrote: > > So, can we assume that the words about a "tape sandwich" refer to a > mylar base, oxide coating, and a lubricant/protective coating? > > That is not an oxide coating sandwiched between to layers of mylar. The 3M spec for the media doesn't quite say it, but yes, that implication is unavoidable from what it does say. paul
Re: Question about DECtape formulation
> On Jan 24, 2022, at 10:27 PM, Gary Oliver via cctech > wrote: > >> ... > > As to the real reason I was doing this: Most of my tapes are un-boxed and > have suffered being in a dusty area (before I got them) with the dust forming > a sort of 'crust' on the outside of the tape. It's only on the first wrap or > so, but it's enough that it keeps those handy vinyl cohesive tapes from > sticking. For that reason, I was trying to find something to clean of this > dusty gunk so the vinyl strip would hold the tape into a spooled condition. > It was the side-effect of this effort that lead me to the discovery if this > "removable layer" on the DECtape. > > BTW, does anyone know of a source for these vinyl strips. My old ones are 10 > mil blue very-flexible vinyl without any adhesive. They rely only on the > cohesive properties of vinyl-to-a-non-porous surface. I tried using some of > the 'dry vinyl' sheets from Cricut (the plastic decal printer company.) They > have a couple of colors without adhesive that they call "window cling" but > they aree only 4 mills thick and a bit flimsy, though so-far they are holding > ok. There's a children's toy I remember: shapes cut from vinyl, intended to be stuck to windows to make pictures. That seems to be the same stuff. paul
Re: Question about DECtape formulation
On 1/25/2022 9:18 AM, Paul Koning via cctalk wrote:
On Jan 24, 2022, at 10:27 PM, Gary Oliver via cctech
wrote:
...
As to the real reason I was doing this: Most of my tapes are un-boxed and have suffered
being in a dusty area (before I got them) with the dust forming a sort of 'crust' on the
outside of the tape. It's only on the first wrap or so, but it's enough that it keeps
those handy vinyl cohesive tapes from sticking. For that reason, I was trying to find
something to clean of this dusty gunk so the vinyl strip would hold the tape into a
spooled condition. It was the side-effect of this effort that lead me to the discovery if
this "removable layer" on the DECtape.
BTW, does anyone know of a source for these vinyl strips. My old ones are 10 mil blue
very-flexible vinyl without any adhesive. They rely only on the cohesive properties of
vinyl-to-a-non-porous surface. I tried using some of the 'dry vinyl' sheets from Cricut
(the plastic decal printer company.) They have a couple of colors without adhesive that
they call "window cling" but they aree only 4 mills thick and a bit flimsy,
though so-far they are holding ok.
There's a children's toy I remember: shapes cut from vinyl, intended to be
stuck to windows to make pictures. That seems to be the same stuff.
paul
Paul,
Are you thinking of Colorforms (https://en.wikipedia.org/wiki/Colorforms)?
To answer Gary's original question: I did find something at
McMaster-Carr: https://www.mcmaster.com/catalog/128/3973 ("Clear
Static-Cling Chemical-Resistant PVC Film").
I don't have any personal experience with it, and it's only 0.007"
thick, so it may not meet Gary's needs.
But if anyone has used it before for tapes I'd love to know if it works
well.
--Bjoren
Re: Question about DECtape formulation
> On Jan 25, 2022, at 3:13 PM, Bjoren Davis via cctalk > wrote: > > > On 1/25/2022 9:18 AM, Paul Koning via cctalk wrote: >> >>> On Jan 24, 2022, at 10:27 PM, Gary Oliver via cctech >>> wrote: >>> ... >>> >>> BTW, does anyone know of a source for these vinyl strips. My old ones are >>> 10 mil blue very-flexible vinyl without any adhesive. They rely only on the >>> cohesive properties of vinyl-to-a-non-porous surface. I tried using some >>> of the 'dry vinyl' sheets from Cricut (the plastic decal printer company.) >>> They have a couple of colors without adhesive that they call "window cling" >>> but they aree only 4 mills thick and a bit flimsy, though so-far they are >>> holding ok. >> There's a children's toy I remember: shapes cut from vinyl, intended to be >> stuck to windows to make pictures. That seems to be the same stuff. >> >> paul >> > Paul, > > Are you thinking of Colorforms (https://en.wikipedia.org/wiki/Colorforms)? Yes, that's it. I would think those will work fine. I remember having something similar as a kid and what I remember is that the thickness was similar to that of DECtape "little blue things". paul
Re: Question about DECtape formulation
On 1/25/22 06:18, Paul Koning via cctalk wrote: > > >> On Jan 24, 2022, at 10:27 PM, Gary Oliver via cctech >> wrote: >> >>> ... >> >> As to the real reason I was doing this: Most of my tapes are un-boxed and >> have suffered being in a dusty area (before I got them) with the dust >> forming a sort of 'crust' on the outside of the tape. It's only on the >> first wrap or so, but it's enough that it keeps those handy vinyl cohesive >> tapes from sticking. For that reason, I was trying to find something to >> clean of this dusty gunk so the vinyl strip would hold the tape into a >> spooled condition. It was the side-effect of this effort that lead me to the >> discovery if this "removable layer" on the DECtape. >> >> BTW, does anyone know of a source for these vinyl strips. My old ones are >> 10 mil blue very-flexible vinyl without any adhesive. They rely only on the >> cohesive properties of vinyl-to-a-non-porous surface. I tried using some of >> the 'dry vinyl' sheets from Cricut (the plastic decal printer company.) >> They have a couple of colors without adhesive that they call "window cling" >> but they aree only 4 mills thick and a bit flimsy, though so-far they are >> holding ok. > > There's a children's toy I remember: shapes cut from vinyl, intended to be > stuck to windows to make pictures. That seems to be the same stuff. > The term of art is "cling vinyl" or "static cling vinyl". Most art stores carry the stuff--mine is a package of this: https://www.grafixplastics.com/materials-plastic-film-plastic-sheets/commodity-plastic-film/vinyl-sheets-film/grafix-cling-pvc-film-2/ Cut the strips with a paper cutter and you'll have enough in a package to last you well into your sunset days. --Chuck
Re: Question about DECtape formulation
On 1/25/22 12:24 PM, Chuck Guzis via cctalk wrote: On 1/25/22 06:18, Paul Koning via cctalk wrote: On Jan 24, 2022, at 10:27 PM, Gary Oliver via cctech wrote: ... As to the real reason I was doing this: Most of my tapes are un-boxed and have suffered being in a dusty area (before I got them) with the dust forming a sort of 'crust' on the outside of the tape. It's only on the first wrap or so, but it's enough that it keeps those handy vinyl cohesive tapes from sticking. For that reason, I was trying to find something to clean of this dusty gunk so the vinyl strip would hold the tape into a spooled condition. It was the side-effect of this effort that lead me to the discovery if this "removable layer" on the DECtape. BTW, does anyone know of a source for these vinyl strips. My old ones are 10 mil blue very-flexible vinyl without any adhesive. They rely only on the cohesive properties of vinyl-to-a-non-porous surface. I tried using some of the 'dry vinyl' sheets from Cricut (the plastic decal printer company.) They have a couple of colors without adhesive that they call "window cling" but they aree only 4 mills thick and a bit flimsy, though so-far they are holding ok. There's a children's toy I remember: shapes cut from vinyl, intended to be stuck to windows to make pictures. That seems to be the same stuff. The term of art is "cling vinyl" or "static cling vinyl". Most art stores carry the stuff--mine is a package of this: https://www.grafixplastics.com/materials-plastic-film-plastic-sheets/commodity-plastic-film/vinyl-sheets-film/grafix-cling-pvc-film-2/ Cut the strips with a paper cutter and you'll have enough in a package to last you well into your sunset days. --Chuck My search results were dominated (even with 'advanced search') by Amazon and Ebay (naturally) but also by a couple of vendors (Cricut as example) and I never found anything coming up for .10 inch or equivalent in mm. This appears to be .10 inches without adhesive so I'm going to give this a try. Thanks VERY MUCH for this link. -- -Gary
Re: Question about DECtape formulation
On 1/25/22 14:06, Gary Oliver via cctalk wrote: > My search results were dominated (even with 'advanced search') by Amazon > and Ebay (naturally) but also by a couple of vendors (Cricut as example) > and I never found anything coming up for .10 inch or equivalent in mm. > This appears to be .10 inches without adhesive so I'm going to give this > a try. > > Thanks VERY MUCH for this link. I found another use for the stuff that may be worth mentioning. I repaired a damaged cable jacket--just wrap a strip of the stuff around the damaged area and apply heat sufficient to fuse the stuff to itself. No adhesives involved. --Chuck
Old Micro Memory core board
Going through an old junk pile, I came across a couple of core boards: Micro Memory, Inc. PN 90360 8K*8 (MM-6800) Date code 7725 I have two boards (s/n 202 and 203) so likely purchased in pairs. Anyone have any information on these? They have 86 pin connectors so not S-100 though connector is about the same size. For years, these have sit on a shelf on my 'round tuit' list of bringing them up in one of my old S-100 boxes, so I've been cruising along thinking these were 100 pin connectors. I got them out today so I could find the manual (I have used the MMI s-100 8kx8 boards in an old company project back in 1977 and those were about the same size and form.) The core board is a daughter board on top of the board with the bus connector and is likely the same module from the S-100 board. I'm guessing the 86 pin bus is a Motorola Exorciser bus - so I can probable figure it out from there, but I would like to find a manual. I think my company had an Exorciser development system in the late 70s. These were obtained from a dumpster dive. Pity I didn't get the rest of the box, if so. As usual, google wasn't extremely helpful with old pedestrian hardware searches. -Gary
