Good stuff Chris, thank you. 

I should chime in that, due partly to fear and partly to laziness, I have 
sidestepped Chri’s much better “take apart and re lubricate” method by very 
carefully heating the axles of the capstans using an RF soldering station and 
spinning the capstans by hand (while quite warm) until they “feel” smooth 
again. Effective Relube without the risk of disassembly.  No new chemicals. 

This has worked on all three tk50s I’ve tried it on and they continue to work 
after, I think, nearly two years. I try to use them often so they don’t sludge 
up again. 

—Jake


> On Sep 3, 2026, at 19:04, Chris Zach via cctalk <[email protected]> wrote:
> 
> TK50's and TK70's have a bad rap for this. The key problem is twofold:
> 
> 1) Tapes stored in dungeons tend to be crap and shed stuff
> 
> 2) The capstans on the TK50 are very important and need to be lubricated
> 
> For the first, I go with good quality tapes and before I put a tape into my 
> collection I clean the heads, then run the tape through a backup or two then 
> check the heads. If dirty I pitch the tape and clean. If clean I clean the 
> heads again and put it in service. Same process you should go through with 
> any new magnetic media (RL02, RX01, etc....)
> 
> For the second you really need to take the drive apart, remove the bolts on 
> the front and rear capstans (marking the bolt's orientation and how many 
> turns to take off) and lubricate the bearings with fine watch oil. They 
> should spin easily the whole problem is the oil dries out and since they use 
> tape friction to turn and the rear one is connected to a tachometer having 
> them drag will drive the tape unit insane and lead to unspooled tapes, read 
> problems, all sorts of insanity.
> 
> Remember they don't have tension arms, the capstans are how they figure 
> everything out.
> 
> Aside from that, fine. I use mine as backups with no issues. Just never 
> introduce a new tape without checking the heads, otherwise the crap will get 
> on your good tapes like an STD.
> 
> C
> 
>> On 9/3/26 17:55, Rob Jarratt via cctalk wrote:
>> Be very careful when reading them, they will shed and stick to the rollers. 
>> You may need to bake the tapes. See this account: 
>> https://www.magneticscrolls.com/blog/tk50-tape-baking
>> 
>> Regards
>> 
>> Rpb
>> 
>>> On 03/09/2026 10:05, hlep via cctalk wrote:
>>> Hi Rod,
>>> 
>>> 
>>> Do you have any external TK 50 or TK 70 tape drives?
>>> 
>>> I'm working at an archive in Germany and we've got some TK-50 tapes and 
>>> we've been looking for some hardware to access them with.
>>> 
>>> 
>>> Best,
>>> 
>>> 
>>> Josh
>>> 
>>> On 2026-09-03 08:37, Rod Smallwood via cctalk wrote:
>>>> Hi Guys
>>>> 
>>>>       My DEC Collection needs downsizing.
>>>> 
>>>>     Im in the UK so for the US only the small stuff would be worth shipping
>>>> 
>>>>     If you need anything PDP8, PDP11 or VAX please indicate item you might 
>>>> want
>>>> 
>>>>      Rod
>>>> 
>>>> 

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