DEC BA11-K noisy fans
Hi all, I've been working on a BA11-K PDP-11/34 lately, and wow it sure is a noisy thing... On my '11/45, the "Boxer" fans were easily disassembled via a cir-clip, and could then have their bearings cleaned/relubed (or worst case replaced). Fan maintenance quieted down the /45 a good bit. But these larger 6" Amphenol units don't look quite as easy to get in to... Is the plastic rotor on these just a press fit? Any tricks to getting in there for maintenance? Or are these "you have what you have" and the only option if unsatisfied with their current performance to replace them entirely? cheers, --FritzM.
Re: Archiving classic computer rubber part information
On 9/11/21 11:09 AM, ED SHARPE wrote: Thanks Al! OK the thickness of tubing is not critical? it is. I used https://www.usplastic.com/catalog/item.aspx?itemid=23485 That black goo is hard to get off the hands.. what have you found to be the best solvent? Ed# goo gone, or something else naptha based this comes up a lot, from all the archived threads 3/8" ID x 5/8" OD x 1/8" Wall TygonR A-60-F Hot Food & Beverage Tubing for TU58 Rik Bos posted: 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 Of course now I can't find my usplastic order for what I used for making 9145 rollers I was also thinking I should try a small pipe cutter instead of a razor blade
Re: Archiving classic computer rubber part information
In addition to the Suns that I collect, I also collect ultra-portable typewriters. JJ Short are recommended for platen and rollers on the Typewriters mailing list and, based on their website, it looks like they could do molded rubber parts for printers. I have heard that they are pricey, but I wouldn't know. Despite sending in quote requests twice, I have yet to receive price quotes for platen and rollers for my typewriters. alan On 9/11/21 9:18 AM, Al Kossow via cctalk wrote: a frequently used place that refurbished typewriter platens has gone out of business. People have suggested https://www.jjshort.com/Recovered-Rubber-Rollers.php as an alternative.
Re: Archiving classic computer rubber part information
Thanks Al! OK the thickness of tubing is not critical? That black goo is hard to get off the hands.. what have you found to be the best solvent? Ed# Sent from the all new AThanks Al. OL app for Android On Sat, Sep 11, 2021 at 10:51 AM, Al Kossow via cctalk wrote: > The roller in the HP cartridge tape drives of various models have turned to > crap also... I have one that came with an HP 3000 series 37 > mighty mouse system thst totally goo-ed a tape Any one with similar > problem find a replacement roller? Yes, they are easily made from norprene tubing. I do the same for DEC TU58 rollers. The trick to cutting them is to put the tubing over a wooden dowel, then cut with an xacto or single-edge razor blade.
Re: Archiving classic computer rubber part information
The roller in the HP cartridge tape drives of various models have turned to crap also... I have one that came with an HP 3000 series 37 mighty mouse system thst totally goo-ed a tape Any one with similar problem find a replacement roller? Yes, they are easily made from norprene tubing. I do the same for DEC TU58 rollers. The trick to cutting them is to put the tubing over a wooden dowel, then cut with an xacto or single-edge razor blade.
Re: Archiving classic computer rubber part information
The roller in the HP cartridge tape drives of various models have turned to crap also... I have one that came with an HP 3000 series 37 mighty mouse system thst totally goo-ed a tape Any one with similar problem find a replacement roller? Ed# Sent from the all new AOL app for Android On Sat, Sep 11, 2021 at 9:18 AM, Al Kossow via cctalk wrote: I've been having fun this past week trying to get the mechanics of a Canon CX print engine in a LaserWriter restored. The paper pick and separation rollers have turned to goo. This got me thinking that people need to start collecting information on rubber parts, like dimensions, material and durometer values for all of these parts before they fail. I found nothing on line about making replacement parts for these. No one stocks replacement parts for anything older than a Canon SX engine (the generation after the CX). Another problem child are Datamation card readers. It's been 20 years now since the last ones were pulled out of service after the 2000 election and there seems to be a steady stream of people trying to make replacements. I think the CHM 1401 guys replaced theirs a few years ago, don't know if they collected mechanical info or where the repair units were made. I've also heard that Terry of Terry's Rubber Rollers is recovering from Covid, and a frequently used place that refurbished typewriter platens has gone out of business. People have suggested https://www.jjshort.com/Recovered-Rubber-Rollers.php as an alternative.
Re: Archiving clamighty mouse sysyemssic computer rubber part information
The roller in the HP cartridge tape drives of various models have turned to crap also... I have one that came with an HP 3000 series 37 mighty mouse system thst totally goo-ed a tape Any one with similar problem find a replacement roller? Ed# Sent from the all new AOL app for Android On Sat, Sep 11, 2021 at 9:18 AM, Al Kossow via cctalk wrote: I've been having fun this past week trying to get the mechanics of a Canon CX print engine in a LaserWriter restored. The paper pick and separation rollers have turned to goo. This got me thinking that people need to start collecting information on rubber parts, like dimensions, material and durometer values for all of these parts before they fail. I found nothing on line about making replacement parts for these. No one stocks replacement parts for anything older than a Canon SX engine (the generation after the CX). Another problem child are Datamation card readers. It's been 20 years now since the last ones were pulled out of service after the 2000 election and there seems to be a steady stream of people trying to make replacements. I think the CHM 1401 guys replaced theirs a few years ago, don't know if they collected mechanical info or where the repair units were made. I've also heard that Terry of Terry's Rubber Rollers is recovering from Covid, and a frequently used place that refurbished typewriter platens has gone out of business. People have suggested https://www.jjshort.com/Recovered-Rubber-Rollers.php as an alternative.
Archiving classic computer rubber part information
I've been having fun this past week trying to get the mechanics of a Canon CX print engine in a LaserWriter restored. The paper pick and separation rollers have turned to goo. This got me thinking that people need to start collecting information on rubber parts, like dimensions, material and durometer values for all of these parts before they fail. I found nothing on line about making replacement parts for these. No one stocks replacement parts for anything older than a Canon SX engine (the generation after the CX). Another problem child are Datamation card readers. It's been 20 years now since the last ones were pulled out of service after the 2000 election and there seems to be a steady stream of people trying to make replacements. I think the CHM 1401 guys replaced theirs a few years ago, don't know if they collected mechanical info or where the repair units were made. I've also heard that Terry of Terry's Rubber Rollers is recovering from Covid, and a frequently used place that refurbished typewriter platens has gone out of business. People have suggested https://www.jjshort.com/Recovered-Rubber-Rollers.php as an alternative.
Re: HP 5061-3476: Which boards go where
At 11:41 PM 10/09/2021 -0400, you wrote: >Hi Guy! > >Thanks for the post and interesting. No it's not quite the exact power >supply but close. However > >Are you *sure* those cards are in the right slots? Hmm... I was starting on that system back in Nov 2013. I'm pretty careful about taking photos of stuff as I take it apart. There's 20 minutes time between the photo with the PS cover on, and the next with it off, showing the boards in place. My memory of that long ago is faded, but I think that 20 minutes was mostly spent looking at the mains voltage selector jumpers, and finding that whoever had originally converted it to 240V had very nicely saved the now unused jumpers in a small plastic bag shoved down between the small transformer and the big blue electro. This was the first time I'd ever opened the machine, let alone extracted and opened the PS. So I am _quite_sure_ the boards are as they were when I got the machine. Its history - I'd rescued it from a junkyard and imminent destruction. It was complete with many I/O cards, two HP tape drives, original HP green racks, but no hard disks. It had been part of a larger system, with no information about its operational condition. Anyway I'd just assumed it was 'previously working, left idle for years.' Then I'd stored it for some more years, untried. Too busy with work, family, etc. Finally got to it. Story: http://everist.org/NobLog/20131112_HP_1000_minicomputer_teardown.htm Where I got to, was quickly attempting to run the power supply by itself, to verify voltages before reconnecting to the system. It didn't do anything sensible, and I'd assumed this was something to do with the PWR CONT IN and BATT INPUT connectors not seeing expected states. So I needed a manual. Asking around, I got in contact with Jon Johnston of the HP Museum in Victoria Australia. He was away mountain climbing. Later I tried again, in the meantime he'd returned then gone climbing in Himalayas again. This time he died there. A good friend of mine had also died climbing in the Himalayas, so this project acquired an aversion factor. Lacking a schematic, I'd have to disassemble the supply completely and reverse engineer the circuits. Not too hard but time consuming. And I was having other life problems. So the machine got boxed up and shelved - JUST before I'd have started actually looking into how the PS was supposed to work. When I would have discovered the board swap. Now, looking at the photos, you are right! Those two boards are definitely swapped. I just dug out the machine now and am looking at it. Thinking back to 2013 I recall wondering about the way the TO3 transistor leg socket-pins on the board next to the big blue cap, were pressing into the insulating jacket of the cap. I recall thinking that didn't seem like a good design. I'd also spotted the two cards _could_ be interchanged, and written "Pre-Reg" on the card that is actually the inverter board. Because it was in the pre-reg slot. Monkey-see... Also noted that the lower TO3 heatsink fins were pressing on the wires from P11. So I bent the fins up a little bit. No reason to think these problems could be due to swapped boards! The slots have "PRE-REG BD" and "INVERTER BD" written in the component silkscreen, right next to them, very obviously. Which makes me feel pretty stupid for not realising the swap, given how clearly the boards are a small regulator vs power driver. Also hadn't thought to check the board part numbers against those listed on the power supply cover. (IMG_6081.jpg) Which would have immediately revealed they were swapped. How did that happen? Someone in the last days of the machine's operation, trying to fix a fault, giving up, shoving stuff back together carelessly? Or a deliberate 'make it not work for the auction' thing? (But there was never an auction.) Or did I have a brain fart, take the boards out in that 20 minute gap, and put them back in wrong - violating my own rule about 'photos first'? (I really don't think so.) Anyway... So now I know I powered it up with those boards in swapped slots. Means I _really_ need a schematic. Maaaybe nothing bad happened. But I'd rather check. All the online PS manuals I've found online are for earlier models. My system is a 2113E. Power supply 5061-6615 SN: 2340 The layout of my inverter and pre-reg boards are different than in the earlier manuals. Pic: http://everist.org/pics/hp1000_ps/20210911_9766.jpg I had also found this manual 92851-90001_Sections-IXB-X_Mar-1981.pdf which is for an earlier PS than mine. I think it came from bitsavers. I've copied it to the same folder as the pics above. Does it match your PS? I _still_ don't have time to allocate to tracing out the power supply schematic. Guy > >Reason I am asking: When I look at the HP docs they label the >Pre-regulator board as A3A1. A3A1 also has the red LED. The inverter >board (the one with the transistors and
