The Sinclair QL Forum

....the thing you designed won't quite fit in your print volume.

Dave wrote:....the thing you designed won't quite fit in your print volume.

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Similar to the awful feeling that you didn’t leave enough water for your cats when going on a long holiday


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That's ok. Just makes room for MOAR CATS!

Here it is: A QL matching dual 3.5: floppy enclosure. It requires a 185x110x70 mm build volume, so a lot of 3D printers won't be able to print it. It also contains some very fine details most PLA/ABS printers won't be able to produce cleanly, like the vents.

I have a large format .05mm resolution SLA printer coming from China that's about 20x the resolution of standard 3D printers. When it gets here and is all set up, I'll print off a bunch of these for the community - some with "QL Floppy", some "Sinclair Floppy" and some blank or custom printed with wording people request. I won't know prices until I cost out the resin and the final weight of these for shipping, but I will be adding a little to recover the cost of a $2,500+ SLA printer. Reason for purchase - the only reasonable <$15,000 way to get production quality prints. Figure on actual printing cost plus $15 for investment recovery - probably somewhere in the $30-45 range, plus shipping. The final unit would take your drives and cable. 95% of drives just need 5V, and a 5V DC regulated 2A wall wart can be used. The Q68 power supply spec matches perfectly. I'll provide a mounted board and power leads with it.

Would also perfectly match the Spectrum +2 etc.

The printer will be used for Issue 8 cases and cases for the new expansions. I'll also do a QL-matching Q68 case if there's any interest. It'll keep me busy on those long days when I'm waiting for PCBs to be assembled and shipped.

Thinks are coming together nicely

And here are a couple of snapshots from my expandable QL concept:
The idea here is that the Issue 8 board fits in the bottom slice, with two SD slots and joystick ports facing forward. All other IO is on the back panel. There's lots of ventilation.

The expansion slice holds four expansion cards. These face out the back, and all common expansion cards will fit, just like to a QL, without their cases clashing. There are PCB guides to make sure they slot in correctly, and another to properly support the backplane. I don't know how many expansion cards the QL can physically address, but two slices and a backplane card would allow 8 physical slots. The concept calls for mixing things up a bit - eg: base holding Issue 8, a slice holding four cards, then a slice holding two floppies, then a top slice that has an HD.

The slices fit into each other using a tongue and groove arrangement, and are held in place by four neodymium magnets in the corners. The left ones are NORTH up and the right ones are SOUTH up, so the case won't go together the wrong way. The top slice has a neat stained wood or carbon fiber insert. The footprint is 220 x 120mm, and each slice is 32mm high, including a 2mm mortice on the tops and tenon on the bottoms.

There is also a slice that can hold a couple of floppies, 3.5" HDs, or one of each. I can also configure it to hold 2.5" SSDs or laptop hard drives.

Each slice is painted on the inside with zinc paint for EM control, then the black resin is sprayed with a semi-gloss ripple texture black paint that matches the QL quite closely.

I developed this concept over the last few years, mostly inspired by the Risc PC, but using the QL's design language. I blanked a lot of that styling for these photos so I don't give TOO much away. There has also been a lot of testing - magnets make people nervous, but the gauss density of the 4x2mm magnets I chose is low enough to not affect any magnetic media even very long term while still providing confident grip between slices. We measured 0.8 gauss at 20mm, from two paired magnets. I'm not sure how much it takes to erase media over time, but we placed a floppy in a field of 1,800 gauss for 48 hours, and no harm was apparently. We could flip bits at around 5,000 gauss, after several minutes, but the meter we had gets inaccurate at higher levels. It was for his project to build an EMP safe hard drive enclosure with optical connections and a very sturdy power supply with known failure modes.

It's been a while since I've shown you guys anything new, so it was a good thing to show as I have been making slow progress in other areas. I'm sharing these concept pieces to you now because my artistic design partner Michele Perini sees a different direction, so these designs might be modified to provide new very compact cases for re-cased QLs.

The backplane slice might also be re-worked to pair well with Tetroid's very nice buffered backplane. I have one, so it's just a matter of waiting for the new SLA printer to arrive. Printing from liquids does give me a lot more choices for printing shapes without supports - neither of these shapes couple print well on an ABS or PLA 3D printer due to the heavy scaffolding requirements they have.

If this gets a moderately good response, I'll design a PROPER QL-style case for the Q68. Michele can also do his idea, and we can see how similar or different they are!

I would really enjoy some feedback. What would YOU put in a slice?

Dave wrote:And here are a couple of snapshots from my expandable QL concept:

Screen Shot 2018-05-04 at 12.56.22 AM.png

Screen Shot 2018-05-04 at 12.57.48 AM.png

The idea here is that the Issue 8 board fits in the bottom slice, with two SD slots and joystick ports facing forward. All other IO is on the back panel. There's lots of ventilation.

The expansion slice holds four expansion cards. These face out the back, and all common expansion cards will fit, just like to a QL, without their cases clashing. There are PCB guides to make sure they slot in correctly, and another to properly support the backplane. I don't know how many expansion cards the QL can physically address, but two slices and a backplane card would allow 8 physical slots. The concept calls for mixing things up a bit - eg: base holding Issue 8, a slice holding four cards, then a slice holding two floppies, then a top slice that has an HD.

The slices fit into each other using a tongue and groove arrangement, and are held in place by four neodymium magnets in the corners. The left ones are NORTH up and the right ones are SOUTH up, so the case won't go together the wrong way. The top slice has a neat stained wood or carbon fiber insert. The footprint is 220 x 120mm, and each slice is 32mm high, including a 2mm mortice on the tops and tenon on the bottoms.

There is also a slice that can hold a couple of floppies, 3.5" HDs, or one of each. I can also configure it to hold 2.5" SSDs or laptop hard drives.

Each slice is painted on the inside with zinc paint for EM control, then the black resin is sprayed with a semi-gloss ripple texture black paint that matches the QL quite closely.

I developed this concept over the last few years, mostly inspired by the Risc PC, but using the QL's design language. I blanked a lot of that styling for these photos so I don't give TOO much away. There has also been a lot of testing - magnets make people nervous, but the gauss density of the 4x2mm magnets I chose is low enough to not affect any magnetic media even very long term while still providing confident grip between slices. We measured 0.8 gauss at 20mm, from two paired magnets. I'm not sure how much it takes to erase media over time, but we placed a floppy in a field of 1,800 gauss for 48 hours, and no harm was apparently. We could flip bits at around 5,000 gauss, after several minutes, but the meter we had gets inaccurate at higher levels. It was for his project to build an EMP safe hard drive enclosure with optical connections and a very sturdy power supply with known failure modes.

It's been a while since I've shown you guys anything new, so it was a good thing to show as I have been making slow progress in other areas. I'm sharing these concept pieces to you now because my artistic design partner Michele Perini sees a different direction, so these designs might be modified to provide new very compact cases for re-cased QLs.

The backplane slice might also be re-worked to pair well with Tetroid's very nice buffered backplane. I have one, so it's just a matter of waiting for the new SLA printer to arrive. Printing from liquids does give me a lot more choices for printing shapes without supports - neither of these shapes couple print well on an ABS or PLA 3D printer due to the heavy scaffolding requirements they have.

If this gets a moderately good response, I'll design a PROPER QL-style case for the Q68. Michele can also do his idea, and we can see how similar or different they are!

I would really enjoy some feedback. What would YOU put in a slice?

Nice !
It would be great if the slice could acommodate the switch for tetroid’s rom changer, and slots for ql sd or the CF cards from tetroids interface. Joystick and serial ports too.
Just my grain of salt
Good work!


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Lovely design, Dave - very much in keeping with the original QL look.

jivrt wrote:Nice !
It would be great if the slice could acommodate the switch for tetroid’s rom changer, and slots for ql sd or the CF cards from tetroids interface. Joystick and serial ports too.
Just my grain of salt
Good work!

The bottom slice has two joystick ports and two SD slots plus LEDs and power indication.

Tetroid's CF card QubIDE would go in an expansion slot, and a cover panel would be supplied that firmly clicks in place, which would provide a slot and guides.

I don't know if Tetroid followed the 'rules' but Sinclair sure did. The expansion card standard size is 160x100mm, which is exactly a half Eurocard. A full Eurocard is 160x200mm. Here's where it gets interesting: On the QL, 80mm is the distance from the tip of the DIN connector to the outside plain of the QL. If your expansion card stops 3mm short of the edge, this allows a 1mm air gap and 2mm of ABS, which is the standard Sinclair used.

I do not have a Tetroid CF QubIDE to measure, but if the hip of the DIN connector to the outside is 77mm or less, it will fit perfectly with a cover. The hip being that line on the DIN connector that the male connector goes up to. The line where the connector reaches its full width.

As for the ROM switcher, I had always intended to include gasket covers for unused slots - that happen to be exactly the same size as the QL's gasket cover. It would be trivial to provide one with a few standard sized holes/mounts/supports for the little DIP switch board. However, I never intended the ROM switcher be useful with an Issue 8 QL, which has Flash anyway.

Thanks for liking it. I am encouraged!

Sparrowhawk wrote:Lovely design, Dave - very much in keeping with the original QL look.

That was the idea. I wanted it to be something where if someone saw it on a shelf, they'd think I had an obscure Sinclair prototype. There were design rules and house style elements I retained, and some I forcefully moved away from:

House style:
Black ABS with a stippled, non-shiny finish.
20mm of angled prisms on the right side and top edge.
Corner cut vents.
Inscribed vertical lines, 19mm spacing.
Angular monolith slab edges.
Most/all connections on rear.

Rejected:
Rectangular LED holes [1]
Expansion on left side [2]

Flaws that remain:
I intended this system to be used either in the regular position or as a tower. Currently, in tower position one whole side of ventilation is obstructed. In a filled system this would be fatal. I did do the angled corner cuts (like behind the microdrives) but they do not provide good ventilation - just styling.

The design goal lets people create the case they need to carry their gear. Only want two expansion slots? Great, it's 32mm shorter. Need four? 32mm taller. Want four floppies? Two floppy slices. All getting a bit too power hungry? A slice with a beefy power supply and a very, very quiet fan.

PHILOSOPHY:
There are three choices for a designer of computers. First, just supply the board. Let the user figure it out. Second, put the computer in a simple, functional case. This would be the Q68's extruded aluminum case. Good EM performance, cheap, practical. A lot of the 80s clones did this also, like the QXTs and the Thors. A beige box, with the floppies in standard places, the keyboard connector bottom right near a power switch, etc. The QX0 did this. The third choice is ultimate adaptability and configurability to the individual user. Acorn's Risc PC got the closest to this. Need another floppy? Boom! Run out of expansion? Boom! Got a special bit of hardware and want to mount some switches, or an OLED display? Boom! With the easy access and lower costs of the new resin-based or laser sintering technologies I get to play with at my maker space, whole new worlds opened up to me and this is possible.

Understanding the rules of design is complicated, though. However, by going back to college for some continuing education and working with Brian - a former Motorola engineer who worked on the 68k family - I've learned a LOT about design for EMI, thermal management (both at the PCB level and case design).

I recently began working with Michele Perini, who reached out to Rick Dickinson and got permission to evolve some of his 80s designs just a few short weeks ago. Michele does this for a living and at a very high level, and has a completely different set of sensibilities to mine. This has forced me to rethink some of my approaches. I have always ran a two-way street: the PCB informs the case design, and the system design informs the PCB design. Art and style has always been a non-consideration for me.

And this is where I start to struggle. It is very easy to riff off Rick's work from 1983. It's good work and it's easy to apply. However, it's 2018, 35 years have passed, and we have a LOT more experience of system design since then. Do we restrict ourselves to Dickinsonian design, or do we call on the very best design elements and experience gained since that time?

So, yeah, I have thought about this.

Other cases:
I did do a version of the bottom slice that can accept standard Nano-ITX (120x120mm) Pico-ITX (100x72) with the standard ATX gasket, or PC-104.

I made (and posted) an external dual floppy case that 100% matches the QL. It just has a very simple PCB so the 5V barrel is connected to two 4-pin flying leads. Only 5% of floppies even use 12v. Modern switching supplies are so much more efficient than 80s supplies. Either way, a simple 12v wall wart could be used and a 5V regulator included for very minimal cost and maximum flexibility.


[1] I liked the flush LED holes, but disliked the trailing six wires that, if the machine were successful, would have had us evolve a third arm by now.. The catch is people could never add their own matching LEDs without a square drill bit. I solve both of these problems by using 2mm round acrylic as a light guide. If the PCB is in place, the board edge LEDs will align automatically. It creates a low profile, flush, invisible indicator with no ugly wires.

[2] I actually had my QL wider than my 3 foot wide desk at one point in college. Ridiculous. Most backplanes put the cards 20mm apart, which is too close and forces you to remove the cover, also ridiculous. Other systems have the cards face up, so the connectors fill with dust. Rejected. This system contains a backplane for four cards, all properly spaced so the cases won't conflict and with excellent ventilation.