Repairing my Apple Tape Backup 40SC Drive and Rescuing Apple History from 36 year old data tapes!

About five years ago I acquired an Apple Tape Backup 40SC drive, an external SCSI drive from 1987 that matches the lovely design of Apple's CD-ROM and external hard drive offerings at the time. The tape drive can take DC2000/QIC-40/80 mini cartridge type tapes, which have a capacity of about 38.5 MB when formatted. It was designed to let you back up your entire Mac's hard drive (assuming you had a standard 20MB or 40MB drive of the time period). I bought it so I could create a video about it eventually.



My plans to make a video were halted when I realized the capstan (or "puck" as Apple's manual calls it) had become sticky and soft. The capstans in these drives all fail due to age, if you use the drive as-is, it usually will destroy your tapes by spreading the soft, sticky goo everywhere. (See "puck" in the diagram above). I opened the tape drive and spoke to @fogWraith about one day restoring it... so the drive went back on the shelf to sit for a few more years.

In early 2024 I snagged another drive off eBay, hoping it would be in better shape - but it wasn't. Then at VCF Midwest 2024 I picked up another tape drive... but it's capstan was even worse! Still in the back of my mind, I wanted to get it working one day. Scouring the web recently I only found many forum and Facebook posts from folks with the same problem. They all had Apple tape drives with sad capstans, all clamoring for the same solution, "We need the measurement of an intact capstan!"...



Fast forward to a few weeks ago, @MacEffects got a very neat haul of vintage Apple goodies asked me if I had a way to read some Apple 40SC tapes. He believed these tapes were made by a former Apple / Claris engineer. This got me thinking again, could I get one of my drives working and what's the safest way to backup these tapes?



There were three big problems I needed to solve:

1) Get a tape drive to work to read these tapes
2) Find out what format the tapes were in or what software made them
3) Figure out what was required to carefully wake these tapes from their slumber


Software for Apple's Tape Drive
Although Apple's 40SC drive came with it's own "Tape Backup 40SC" software (and is only compatible with System 6 or below), that wasn't the only game in town. Apple actually bundled copies of Dantz Retrospect at some point with their drive. However, there isn't a clear way to tell what format the tapes are in without popping them in a working drive.

I would later learn that Apple's own tool let you format the tape in two ways. Option 1, as if it were a hard drive - allowing read/write capabilities right from the Mac desktop!. Option 2, more like a traditional tape drive, where you can select data to write to the tape as a session, and return later to write more data to it.



Learning about drives and tapes:
I did some research about the format, but was quickly overwhelmed by the different tapes, formats and drives that used DC2000 / QIC style tapes. The tapes in question are QIC-40 mini cartridge tapes (or QIC-40 MC), this is important because there are many different sized QIC cartridges of the day. (See below for some size comparisons!)

I thought about acquiring another SCSI tape drive that could read the QIC-40 MC tapes... but it seems every Apple drive is toast and not many companies made QIC-40 style tape drives for the Mac (or that were SCSI). The closest match were tape drives made for MS-DOS / Windows. To cut costs those often connected through a floppy disk controller (FDC) port. Which makes sense, this format was seemingly aimed at consumers and not professionals, and for backing up a few megabytes of data that's one way to do it if you don't mind waiting.

The older, larger QIC cartridges (see photo below) have their own challenges, but the design is largely similar to the smaller ones. AJ of Forgotten Machines has a great website chronicling their QIC tape adventures on their website and YouTube channel. I sent off an email to AJ hoping for some advice, but didn't yet hear back, and later realized they specialize in the larger style tapes.



Left photo: A photo a larger style QIC (150MB) tape from fileformat.info, about 6 inches / 15.24 cm in length.
Right photo: A photo of my Apple QIC MC 40MB tape (sometimes called a mini data cartridge or micro cartridge) - a bit over 3 inches / 7.85 cm in length.

Luckily enough I had a few QIC-style tape drives in my collection already! Yay hoarding collecting!

First up was a Colorado Jumbo 250, a Gateway branded Jumbo 1400 (which was oddly enough hiding inside a UMAX Mac Clone I picked up!) and a LaCie external Travan TR-1. Out of these drives it seems technically only the Jumbo 250 drive is the only one compatible to read QIC-40 or QIC-80 tapes. Usually tape drives are backwards compatible with one prior generation of tapes or formats, so a QIC-80 drive would usually be able to at least read QIC-40 tapes, etc. The tape standards are a bit confusing, but there's website here with more info on Qic.org.


My SuperMac J700 Macintosh clone had a PC-style tape drive (Jumbo 1400) installed by a previous owner, despite the fact that it wasn't compatible with any Mac I/O interface.

First Idea: Imaging QIC tapes via a Pentium PC
I looked inside my Colorado Jumbo 250 and 1400 drives and their capstans looked to be in good shape, and furthermore were easily accessible and more serviceable than Apple's tape drive, (more on that later). I had some new old stock blank QIC-100 tapes from the late 90's, they had a URL / email address printed on them, so they were at least from 1995 or later I'd imagine.

I had everything I needed to try my Jumbo 250 drive on my PC. After some trial and error, I got my drive connected to my NEC Pentium II box. With Windows 98 installed I fiddled with some DOS software, but nothing seemed to see the drive. Tape Mate II for DOS seemed promising, but when I tried it, it only wanted to see or connect to SCSI tape drives, and mine was a floppy-controller based drive.



Someone online mentioned Arcada backup, a nice GUI app for Windows. With that I was able to successfully configure the tape drive (it saw it as a QIC-80 drive) and test the new tapes by writing data to them, and restoring data from them. I was successful, so I had confirmation that my Jumbo 250 drive worked and my QIC-100 tapes were compatible! I also fiddled with my Jumbo 1400 drive, but since I saw reports it wasn't QIC-40/80 compatible, I stuck with the Colorado 250.



However, I knew the unique format of the Apple tapes likely couldn't be read by a Windows system... as that's not even possible for a standard Mac floppy or hard drive. But maybe Linux could help?


Linux waddling
I came across some helpful videos by CelGenStudios and Dmitry Brant and learned a lot about the QIC tape format. I'd highly recommend both of those videos, please check them out.

Dmitry's video showed him recovering tapes with a circa 2005 Linux distro, CentOS v3.5 (with kernel 2.4.21). This had to be specific because apparently tape drive support via Linux's ftape and zftape tools (ftape is for floppy disk controlled tape drives) were removed in Linux kernels. Thankfully the video seemed straight forward enough... but I wasn't a Linux expert and the video wasn't really a tutorial.

After some kind support by @GutBomb and some hints from @Action Retro I cautiously moved forward with Linux. After going down some rabbit holes I discovered Dmitry had a GitHub page, which documented their ftape instructions for CentOS 3.5 (and similar). Sadly that wasn't linked to their YouTube video at the time, but I'm very glad I stumbled upon it by pure luck!

Getting Linux installed on my old PCs was hindered by some questionable cheap SSDs I scored off eBay. It also didn't help that the CentOS install DVD .iso was long gone, so I had to burn three CD-Rs instead... yay disc swapping! A turtle's pace of an install (2-3 hours) should have been the clue, but not doing this before, I blamed the old CD drive. Slowness and solid hard drive activity lights aside, I was still struggling with the instructions on the GitHub page - as it assumed you knew some Linux things, which I clearly didn't.

At this point I realized the aging SSDs were the issue. I recalled I just got a newer SSD from Tom Barber at the recent VCF East Swap Meet, and I put that into an eMachines Celeron D system I tripped over in the basement. I think I picked this system up just for $10 or $15 purely for the stickers, the "QA / warranty void" sticker was still on the door too - so I hadn't even opened it yet. I'm glad I did as the thing was caked with dust inside, but after a good cleaning outdoors I put in the SSD and performed a CentOS 3.5 install. To my delight, instead of taking 3+ hours to install - it took only ~10 minutes!!


I love how silly this tower looks with the tan/brown tape drive installed!

After stumbling around a lot, I reached out to Dmitry but just by luck figured it out! You see, after following their steps, I needed to perform a `modprobe zftape` to start the services, then navigate to the `modules` directory and do an `sh insert_floppy` to run a script to do... stuff related to ftape/zftape and my tape drive. That seemed to do the trick. I'll write some detailed instructions later, but with this I was able to put in the tape I tested on my Windows 98 PC and dumped the data (via the dd command) via the Terminal. Success!

Since I was able to dump a PC tape via Linux, I assumed I could do the same with an Apple tape, because why would Linux care about the format? That would be something to explore for sure...


The capstan from my Apple 40SC Tape drive from VCF Midwest, yum!

Apple Drive Capstan
Since I didn't want to put all my eggs in one Linux-shaped basket, I continued tinkering with the Apple 40SC tape drive to see if I could find a solution for the capstan (or puck). The problem is, there is no record of what the size of this capstan should be!

The mechanism of my Jumbo drives differ so their capstan may not work with the Apple drive. At least the power supply in the external tape drive case seemed okay, so hopefully that wouldn't give me trouble.

Sadly the drive I had on my desk had a very sad capstan. It was very puffy and had turned to a sticky cork-like material (see photo above). Still, I carefully opened the case of the drive. Inside was the tape drive mechanism... sandwiched in by three circuit boards, plastic spacers, metal standoffs, a dozen screws and some delicate ribbon cables. SO FUN!



After carefully opening up the drive to reach the capstan I took some photos and measurements. I knew this wasn't an ideal candidate, the rubber or whatever material was all gone. I remembered I had gotten another Apple drive off eBay... and maybe had a third, but my basement search turned up empty... for now.


3D Printing Adventures
However, knowing the measurement of the bare metal capstan motor spoke, I now had a "too small" and a (rough) "too large" range I had to work with based on the open area in the Apple drive. In theory I could 3D print dozens of test capstans (or donuts as I joked with friends) to see if one would do the trick. After all, I had some test cartridges and an already broken drive. What's the worst that could happen?

The Apple drive capstan in tape drive #1 was almost bare metal, with a < 1mm ring of the sticky capstan remains around it. I measured its width (about 12.8-13 mm wide and 6.4mm tall) and gently pestered my pal @GutBomb intro creating a 3D printable capstan from my measurements via OnShape. The unknown variable was of course the width of the capstan that would make contact with the tape's own plastic capstan. I started with three sizes printed in PLA, 1mm, 1.4mm and 2mm in size.


Mmmm... revision A donuts!

The adventures continue in the post below...

First steps with PLA
I knew PLA would likely be too tough and ordered some flexable TPU but it wouldn't arrive for another day or two, so I proceeded to experiment just for to explore sizing. I got the inner spoke size pretty spot on. Since there was some sticky residue from the deteriorated capstan the 3D print held on well, perhaps too well. I read of someone else using kapton tape to act as a buffer when creating replacement capstans, so I tried adding some of that on the 1mm print... but when I loaded my test tape, nothing happened - it wasn't making contact or spinning the tape's capstan or reels. I tried again with the 1.4mm print and used a tool to nudge the capstan around from inside the drive (while it was off). The tape sort of moved, but not reliably. Last I tried the 2mm print - this kinda worked? It moved the tape... but there was one more wrinkle.



Unlike the Colorado drives, the capstan on the Apple drive sits on a spring-loaded platform with a hinge. When the tape is inserted the drive's capstan (and motor) are pushed away from the opening of the drive and upwards at an angle. This makes the tape's capstan put pressure to the tape's plastic capstan at an angle as well. So even if the tape inserted well, it was difficult to tell if it had the right amount of pressure or tension from the drive capstan. See the diagram below to see what I'm talking about.



Let's test it...
Now I knew PLA wasn't ideal, but I powered up the drive anyway with one of the capstans to see how it functioned. Since it didn't move on it's own, I inserted one of my blank tapes. I had System 7.1 running on a Macintosh LC. With the tape system extension installed it threw a generic error that the tape drive wasn't responding. However, the error went away when a tape wasn't in the drive. So after fiddling around with it a bit, and swapping different PLA capstans, I put in my blank tape and I got a brief moment of joy... the program started to rewind the tape! The drive made horrible noises and eventually stopped and blinked error lights. But it did something!! I ejected the tape a few times and tried again, and each time it seemed like it wanted to try. So I made some notes, adjusted the amount of tape on my plastic capstan and tried again.

In my excitement I must have grabbed the wrong tape by mistake... the (hopefully) blank Apple tape. I watched as the drive tried to spin the tape, then I heard a bad sound... and the tape media appeared where the tension band was. Clearly - something went horribly wrong. I pulled the tape out and to my horror saw the Apple label. In my defense it was nearly 4 AM but I was silly not to put the Apple tape away in it's case to keep me from getting confused with it.

However, this taught me a valuable lesson about how these tapes work. Through some miracle the Apple tape media wasn't permanently damaged. Nothing had snapped except for the worn tension band. But the tape's plastic capstan did get a bit taken out of it. This is when I discovered that the Apple tape capstans and the new Imation tape capstans weren't identical. Of course not, why would they be?! The middle spoke size differed so they weren't interchangeable.


The damaged tape capstan from the Apple tape, you can see the bottom is broken.


I was able to carefully untangle the tape, which had gotten folded over and bunched up in a few areas. It appears when the band snapped the tape came off of the spool, and thankfully when the tape's capstan broke, things stopped - preventing the tape from further damage.



Tape surgery...


Tape Spooling
Wait - how did the tape come off of the spool, did it rip off? No - the tape media simply is not attached to the spools! They're held on simply by tension. There are marks (pinholes) on the tape media that tell the drive it is nearing the end of the tape so the drive knows to slow down and stop spinning. Since the tension band is directly pushing against the reels, there's little reason to adhere the tape to the reels themselves. This would be good to know for the future.


Learning about tension bands
The next day I inspected one of the other Apple tapes. I rubbed my finger across the tape's plastic capstan and realized as I did that, the tape media's retained it's shape as it moved around in the cassette. The tension band and the tape were in the same spot for over thirty years... I've read horrifying stories of tape media being pulled into layers and ripped apart due to this act. Thankfully this only seemed to pull the tension band crud onto the tape... it didn't seem to pull the tape media to bits.

The tension band on these QIC and QIC MD tapes is crucial to the tapes working. Unlike a traditional audio cassette, the design of these QIC tapes don't allow for direct movement of the reels. The plastic capstan and tension band literally push against the media and two plastic wheels to move the media around. So the only thing moving the reels around is this band and friction to that plastic capstan on the tape.

After watching AJ's videos on opening his larger QIC tapes, I opened one of my blank tapes to get a feel for it. The new old stock tapes from the late 90's still had strong and springy tension bands. As soon as they are removed from the tape they'd bunch up into a tight twisted coil.

But after opening another Apple tape I realized the tension band was shot! It was dried out, brittle and stuck in a T-shaped pose from sitting idle for 36 years. I assumed my new old stock Apple branded tapes, or any manufacturer's QIC tapes this era would have the same problem. So that's a big warning to anyone going down this rabbit hole... don't expect old tapes to have good tension bands!

The tension band removed from the old Apple tape, notice how it retains it's inverted T shape even after being removed!

AJ's experience repairing the larger QIC cartridges gave him some tension band replacement options, but those wouldn't work here. Measuring the old (stretched out) snapped off Apple tension bands myself, they seem to be about 240mm in length, 3mm tall and about 0.1 or 0.2 mm thick. However, a new band from a NOS tape measures about 180mm in length. These may be good base measurement to keep in mind. While struggling to search for suitable belts online, I realized - wait a second... my new old stock tapes have good belts, how hard can it be to swap those over to the Apple tapes?!?

The horror continues
It turns out swapping tension bands was the most painstakingly terrifying and sweat inducing part of the whole project. Because of the tension at play you need to be super duper careful, have steady hands, plastic tools at the ready (because magnetic ones could harm the media I suppose), and be careful not to break anything. Following AJ's larger QIC tape videos I learned some good tips. I taped down the cassette to my desk to avoid the cassette and the reels from moving too much.


More open-tape surgery

Using some plastic pry (spudger) tools I was able to carefully remove the band from the new tape. I taped down the blank Apple tape and opened it carefully. I borrowed a plastic tape capstan from another Apple tape. (Thankfully removing that was easy, as the tension band was shot).

After an intense 45 minutes, and a lot of cursing, I was successful! After some super tiny adjustments the band was on correctly and the tape didn't have any slack. I wouldn't be using this tape right now, but once I had success with a blank Imation tape, this Apple would be the next step.


Flexibility filament fun!
My TPU filament arrived thanks to @jcm-1 and @GutBomb I was quickly up and running printing tons of flexable capstans for my Apple tape drive. Again, the issue was that I didn't have a good capstan to work from. So this was pure guessing. I started making some 1mm and 2mm thick donuts, and then made some 4mm and 5mm ones, along with some in between. The TPU donuts, err.. capstans, fit well but the tape drive still wasn't happy or reading the tape. I just got generic errors from the Mac.




This is when I discovered that the Apple tape software isn't supposed to work with System 7. So instead I tried with System 6.0.8, and was sadly met with similar errors about the tape drive not responding. Hm... This got me thinking, maybe the drive was bad? I pulled the drive apart, dumped the EPROM (which had no protective sticker on the window) but that seemed to be okay.

This forced me to find my other Apple tape drive(s) just in case. After days of searching I stumbled upon one, wrapped in thick bubble wrap and hiding next to a box of disks. I opened the drive and sadly the capstan was even more bare than my previous model. Damn.



Days later I finally stumbled upon my third drive - which oddly enough was the first one I ever got, and tinkered with way back in 2020. It was hiding on the shelves behind my set all along. I'd say it was hiding in plain sight, but there was a bunch of crap in the way.

I opened that drive and to my delight THE CAPSTAN LOOKED INTACT! Sure it was a bit sticky, but I could now get a measurement of the dang thing! 17.4 mm was the total width (including about a 12.8 to 13 mm metal spindle in the center). Measuring a width of about 3.4 mm was what I needed to print.



Now that I had my TPU filament, after some frantic 3D modeling and printing I produced three new capstans. They measuring 17.4 mm, 17.8 mm and 18 mm wide (again including the metal capstan inside). When they printed however the smallest was a half millimeter or so smaller. When I placed it into the tape drive and spun it, it kinda moved the tape, but I still got the same error as before.



So I then tired the 17.8 mm capstan and... but the same thing. "Tape drive not responding". Hmmm... maybe it wasn't the drive but the system? Maybe it was temporarily cranky?


Photo of the 3D printed TPU capstan in my Apple 40SC Tape drive.


Ready for PowerPC Upgrade
I had just tried a Seagate Travan drive in my Power Mac 8600 with another blank QIC-100 tape, but it was too old to be backwards compatible, even if the tape physically fit. Dantz Retrospect only gave a "Media failure" error on a brand new tape. Looking further into the drive's specs (which are harder to find these days) it seems this may not be compatible with these old tapes. Bummer.



The next day I had a thought. What if System 6 is just being cranky. I have Dantz Retrospect on my Power Mac, I used that for recovering some DAT tapes. If Apple bundled Dantz with their drive, surely at some point it had drivers for it, right?



I removed the Apple tape drive from it's case and installed it in my Power Mac 8600. This poor thing hasn't had bezels on it in years, as it serves as my go-to SCSI workstation. I placed the Apple drive upside down to avoid shorting anything out. Let's just say I may have killed one of my Apple tape drives this way... . It was jank, but hopefully it would work.

I booted into Mac OS 8.6 and started up some SCSI tools and tape tools (like FWB HD Toolkit, DeskTape) and it saw the SCSI drive. I then launched Dantz Retrospect 4.0.x, clicked on Tools / Configure to look at the SCSI devices. And there it was, it saw the drive!



I inserted a new QIC-100 Imation tape and the tape drive spun in the drive, I could see the tension band moving! But then... after a promising "Loading" status, I got a hardware error message. I ejected the tape and tried again and got a different error. I tried a few more times and the status eventually changed from "Loading" to "Busy"! Shortly after it said the tape status changes to "Content unrecognized", but it did allow me to format it.

Hooray! The 3D printed capstan worked (the "B" 17.8 mm size) and the Apple 40SC tape drive successfully read a tape!



Retrospect was able to successfully format the tape after a number of minutes and I was able to successfully write data to the tape and retrieve it! I was super duper pleased with myself, the Apple tape drive worked, at least for now.




Important note about fit and usage of the 3D capstan!
Although my capstan fit on snug and stayed on without any glue, I did notice after multiple uses it did slip a bit off the spindle. I was able to slide it back on via a spudger without opening up the drive. I also noticed some very fine TPU particles collected inside of the drive, but not too much to worry about. But either way, if you'll be using this method, I advise you keep an eye on the replacement capstan carefully during the drive's use!

My thought process was now this...
I wasn't super happy with the cranky Apple tape drive, but if I could format a tape on the Mac, I could test if my Linux PC could dump the tape. I then put that Retrospect formatted tape into my Linux box, but was greeted with "Permission denied" errors. I was so frustrated, what did I type wrong? It worked on my PC tape. Nothing in my configuration had changed, I had this working just hours ago! Digging further into var/log/messages I discovered this was a false error. The real error was the ftape process couldn't determine the format of my Macintosh tape! The error read `zftape-read.c (check_read_access) - tape is not formatted.`

I suppose the tape drive couldn't find the sectors or format it expected and tells the system of it's failure. No matter what I tried, Linux wasn't an option. I was hoping the dd command would be platform agnostic, but I guess the tape drive or driver had other plans.




Trying an Apple tape on the Apple Tape drive
Now that my Apple drive was working in my Power Mac, I tried to load the unlabeled tape (that I assumed may be blank). I shared this plan with Mark and he agreed my logic was sound. I nervously put the tape in... it spun around furiously for a few minutes and Dantz eventually returned a status: 'Content unrecognized".



Well that's not totally bad! It kinda read the tape? Maybe the tape was blank after all?

Since the drive was working with my Power Mac, I tried it again with my LC, keeping the drive upside down (after all, maybe that was the magic trick?) -- booting to System 6.0.8 with the Apple tape drive I inserted the tape again and a new dialog eventually appeared. "The tape cartridge is blank".

Yay! The drive seems happy now in the LC and I confirmed the Apple blank tape Mark lent me is actually blank. Awesome!



Trying Wild Things
The next tape, labeled "Wild Things Backup". I did the same super painful process of transferring over anew belt to this tape. After that, I tried it in the Mac LC with the tape drive connected... and I got this message! "The tape cartridge contains information that is not recognizable by Tape Disk. Use the application that wrote this tape cartridge originally." Awesome, now I had to a clue to try it with Dantz on the Power Mac, so I got the drive plugged back into the Power Mac to try things with Retrospect.



The tape whirled and loaded and eventually Retrospect displayed this wonderful status - showing the tape name!!

Now unfortunately the original hard drive or system that made this tape is elsewhere. That contained the catalog file for the tape. Thankfully, Dantz has a way to generate that from a tape if you lost that file. However, it basically has to read all the contents of the tape.



The good news is that process didn't take long and that it was successful! Only about 6 megabytes of data were on the tape (out of a possible ~38 megabytes). The amazing thing is that this tape has plenty of releases, likely source code, and other goodies related to Claris Wild Things. This was a program that seemed like an "idea management" style software. Kind of a mix between HyperCard and AppleWorks? Either way - there are proposal docs, meeting notes and some code on this tape. The majority of the tape contents were different releases.




The bad news, is that this tape wasn't 100% happy. After doing a test restore or two, Dantz warned me that it detected media failures. I also had trouble recovering a file or two. This drive is also S L O W , often peaking at just 0.2 MB / minute, it doesn't help that the tape drive must rewind and fast forward for about 3-5 minutes before each action.

Thankfully the Dantz software saves the catalog on the computer, so I can open and view the contents of the tape without having the tape in the drive (unlike Apple's software). Eventually I nursed the tape enough to get all the data off. Which was good because during the process I was scared to see this message pop up... !



I have two more tapes to discuss, but I'll post an update below with the details of those, as they are unique. Once the recovered data has been reviewed Mark and I will share where it can be found, etc.



Hopefully this information about rescuing QIC tapes, the tape drive, and the 3D model of my capstan, will help others in a similar situation. It has been a wild ride... will catch you back here next time for more!

The 3D models are attached to this post. I used the one labeled "Apple 40SC Tape Capstan 1 (Works) - 12.4 center - 17.8 total by Mac84.step" but there are two others of slightly different sizes that also may work... as you can see, a lot were tried!!