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[stepleton]

Those photos that Ray found are timely, since I have a mind to service my Twiggy drives. I thought I'd check---has anyone got any tips?

Like most floppy drives of their age, the moving parts in mine are dusty and likely no longer as free-moving as they once were. Some cleaning preventive lubrication seems worthwhile. There are also a few axial electrolytic capacitors in the drives as well, which I plan to check in-circuit with an ESR meter---although I'm usually a pretty proactive recapper, I am more inclined to take a "watch and wait" approach for these boards.

Molykote EM-30L has been recommended on other forums as a good specialty grease for lubricating floppy drive mechanisms, particularly around plastic parts. It contains lithium grease as an ingredient, which is another common choice. The Twiggy Manufacturing Instructions on Bitsavers meanwhile, suggests that the rails for the head carriages may have used teflon grease, or were perhaps permanently coated somehow? (PDF page 32: "Make sure the guide rails are teflon coated").* Later on (page 56), it actually mentions using good old Tri-Flow teflon lube on the stepper motor lead screw.

(The manufacturing instructions have other encouraging notes like the one attached, and they reveal also that there are parts of the drive called "the serpent", "the froggy", and "the alien".)

My aims are to get rid of dust on moving parts at least, clean the heads, lubricate where appropriate, and inspect parts that seem perishable (e.g. foam pads, drive belts)---even though I am not sure what they ought to be replaced with if they seem degraded.

In any case, I thought I'd ask around here to see if anyone had any thoughts about this kind of work, or suggestions. Does anyone know of any other resources for servicing overcomplicated floppy drives extremely carefully?

* Funnily enough, I got in touch with the author of that document... sensibly enough he can't recall whether it was grease or a coating.

[ried]

Sorry to bring up an old thread, but it looks like the question remains.

I'm hoping to track down a set of Twiggy drives at some point and have been wondering about this question, too. Is anyone familiar enough with these drives to service them properly? What would refurbishment involve? What are the potential pitfalls and, importantly, cost implications of such a service?

My experience trying to rehabilitate a Widget has made me keenly aware of my own limitations.

[sigma7]

Some thoughts:

It seems doubtful that any Twiggy drive has been used enough to have any significant wear.

In my experience, the foam pads that press on the jacket increase friction substantially (which, along with poor belt traction, made some disks stop rotating), so I would not replace them. I wrap them up (using a piece of paper, taped) so they no longer make contact.

The felt head pads need to be present of course, so replace if missing.

If you're using old media at all, you'll need to clean the heads frequently (as often as once per disk if you are archiving originals). Accessing the rear head for inspection/cleaning is a real pain.

BLU has a head shuffle command that I use to wipe the heads on cleaning material w. alcohol (currently using a Texwipe AlphaLite as that's what is on hand). I tape a piece of the fabric over the head openings of a scrap disk; I have pondered how to make a disk shaped fixture to hold the fabric so it is quick to change and eg. has a mirror so one can see the rear head, but haven't got a good solution so far -- any ideas?

I'm now using a 3d printed contraption to tension the belt when a disk is in place (since a replacement belt isn't easy to find). I'll post the design at some point when I'm more confident that revisions won't be needed; if anyone would like to be a beta tester in the meantime, please let me know.

There is also a 3d printed jig for cutting the jacket openings to make new Twiggy media... currently have one beta tester, more are welcome.

Adjustments are few; one for speed and the other the track 0 position sensor. I recommend that you not move the track 0 sensor until there is an established method of getting it right.

[Jacexpo]

I have bought 100 floppy disks with the intention of making a jig to create twiggy compatible devices, but would like to see if there is one already available - even if need to beta test. Maybe you don't mind reaching out via PM to see?

Thank you

[paule]

100 disks I presume? 100 drives would be incredible!

[Jacexpo]

Alas - if only it was so!!!
Yes, only disks.

I did find this site in Italy that has reported they were going to make new twiggy drives - but whereas the site is still up - no one seems to be home to answer the emails or web postings.

https://www.memsys.it/memsys/en/repair-services/apple-vintage-repairs/twiggy-drive-project/

[sigma7]

... intention of making a jig to create twiggy compatible devices, but would like to see if there is one already available

I started a thread in the files section ... Twiggy Media

[sigma7]

I did find this site in Italy that has reported they were going to make new twiggy drives - but whereas the site is still up - no one seems to be home to answer the emails or web postings.

I was helping Mauro (or at least trying to) with some details for this project starting in 2009; periodically there is progress, but it is a major and not inexpensive job.

[ried]

Does anyone know if the press-fit plastic spindle (?) in the Twiggy drive can be sourced from another 5.25" floppy drive? I'm talking about the black plastic rotating disk in the center:

https://www.flickr.com/photos/114907644@N04/12035353993/in/album-72157639938971695/

https://www.flickr.com/photos/114907644@N04/12035087135/in/album-72157639938971695/

It comes down onto the topside of the FileWare disk's central hub and facilitates rotation of the donut.

https://www.flickr.com/photos/114907644@N04/12035908166/in/album-72157639938971695/

[sigma7]

Does anyone know if the press-fit plastic spindle (?) in the Twiggy drive can be sourced from another 5.25" floppy drive? I'm talking about the black plastic rotating disk in the center:

If you mean the thing that clamps the hub of the media and spins (see pic), then I'm not aware of any substitutes -- let us know if you find any ... I'd guess an adequate replacement might be 3d printable, though not a trivial design task.

Recall that the Twiggy & Widget designs were consequences of the so-called NIH (Not Invented Here) discrimination syndrome at Apple at the time, so deviations from industry standard were often severe.

Although the clips around the perimeter are springy, there is almost no friction between this one and the spindle, so I think the spring requirement is minimal and perhaps unnecessary if the fit is good.

I was able to 3d print one of the kickout clips, and it seemed to work ok... it needs some design tweaks to print better and be more durable but as a proof of concept I think it is successful.

[ried]

Does anyone know if the press-fit plastic spindle (?) in the Twiggy drive can be sourced from another 5.25" floppy drive? I'm talking about the black plastic rotating disk in the center:

If you mean the thing that clamps the hub of the media and spins (see pic), then I'm not aware of any substitutes -- let us know if you find any ... I'd guess an adequate replacement might be 3d printable, though not a trivial design task.

Yep, that's exactly what I'm looking for. I was hoping that it would be a standard, off-the-shelf part used elsewhere else. Hrmph.