I think I misread you answer, 4mm tube for me is 4mm inside diameter, I suppose you mean 4mm wall thickness. And the inside diameter of the 9144/45 is 12mm (~.5") the outside is about 18mm (~.7") (~3mm wall thickness). I use polyurethane to make the new capstans, turn them on the lathe. -Rik -----Oorspronkelijk bericht----- Van: cctalk <cctalk-bounces at classiccmp.org> Namens Chuck Guzis via cctalk Verzonden: vrijdag 23 april 2021 20:24 Aan: CCtalk <cctalk at classiccmp.org> Onderwerp: Re: hp 9145 capstan replacement On 4/23/21 10:33 AM, Rik Bos wrote: How do you figure that? I've got a DC600HC cart here and it's the same dimensions as a standard DC600A cartridge--it is Iotamat preformatted, without the usual optical sense stuff. It was used on a number of QIC (yes, it's quarter-inch) drives, such as the Kennedy 9455 and the ADIC 32-track drives. As far as the capstan being too large, I suspect you may underestimate the "stretchiness" of silicone hose. Somewhere, I posted a photo if an Archive 2060S drive with a red hose replacement capstan. The hose comes in larger sizes, regardless. I still need to refurb the capstan on my 3M DCD-01 drive, but it's been too long since I've run into any 2-track DC300 tapes, so it's not a priority. In any case, the suggestion is offered for whatever value one can gain from it. --Chuck