520ST PSU Remake

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exxos
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Re: 520ST PSU Remake

Post by exxos »

rubber_jonnie wrote: Thu Apr 18, 2019 2:26 pm Interesting. For me the bottom section was estimated at 5h 43 with 20% infill at .3mm. Top was 6 hours exactly. I can't remember travel times and print speeds off the top of my head.

@ .2mm both were 7 hours +.

I should be able to add a pic of the top sometime tonight.
0.3mm layers gives me 3hours 3mins.

0.2mm 4H 17mins.

0.12 (my default currently) 6H 38mins.

So I may try 0.2mm on my boxes next...
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
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Re: 520ST PSU Remake

Post by rubber_jonnie »

As promised, here is the top of the case:
IMG_20190419_090514.jpg
IMG_20190419_090514.jpg (253.29 KiB) Viewed 4930 times
Next is cleanup and final assembly.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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Re: 520ST PSU Remake

Post by exxos »

Looking nice!
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
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Re: 520ST PSU Remake

Post by PhilC »

Looks great RJ. How long dud it take to design it?
If it ain't broke, test it to Destruction.
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Re: 520ST PSU Remake

Post by rubber_jonnie »

And some more pics.

Top and bottom together:
IMG_20190419_092406.jpg
IMG_20190419_092406.jpg (255.35 KiB) Viewed 4921 times
And the two parts fit together very nicely :)
IMG_20190419_092355.jpg
IMG_20190419_092355.jpg (197.03 KiB) Viewed 4921 times
The top half still requires the vent holes and 'flash' to be cleaned up.

I know 'flash' is typically a term used for injection moulding, but it looks very similar to the brim of a 3d print.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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Re: 520ST PSU Remake

Post by rubber_jonnie »

PhilC wrote: Fri Apr 19, 2019 9:29 am Looks great RJ. How long dud it take to design it?
I'll be honest Phil, I can't take credit for the design, through discussions with various other people I was directed to it on Thingiverse, there is a link early on in the article.

It was designed specifically for the PSU I was using (or its variants), by someone replacing an Amiga PSU.

Thought it would be silly to try and reinvent the wheel.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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Re: 520ST PSU Remake

Post by Icky »

:coolpics: Nice
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Re: 520ST PSU Remake

Post by PhilC »

Makes total sense to me RJ. And looks like it will clean up nicely.
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Re: 520ST PSU Remake

Post by rubber_jonnie »

Hmm, suspect my change to .3mm has had a side effect in that the top vents are really hard to clean the support structure out of.

Still, you live and learn, this is probably the largest most complex piece I've yet printed, so first go was always going to be a try out.

It is cleaning up ok, just taking longer than planned.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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Re: 520ST PSU Remake

Post by rubber_jonnie »

OK, so it's finished and happily powering my 520ST 😁

IMG_20190420_152034.jpg
IMG_20190420_152034.jpg (305.65 KiB) Viewed 4884 times
IMG_20190420_154511.jpg
IMG_20190420_154511.jpg (273.51 KiB) Viewed 4883 times
IMG_20190420_154529.jpg
IMG_20190420_154529.jpg (213.15 KiB) Viewed 4883 times
Project over, what would I say are the gotchas?

Well, in all honesty, the worst part was the top half of the case.

My decision to print @ .3mm bit me down the line, as the resolution was too poor to do a good job of the case vents, leading to a lot of filing and picking away support structures that simply weren't fine enough.

It's also possible that another material, such as ABS may be a better choice when printing.

What I gained in a faster print speed, I lost in tweaking the case to clear the air vents.

Other than that, it was a pretty simple process.

I hope this gives someone the confidence to have a go when they need to replace a PSU that is not a common item any more.

As an aside, this same PSU can be used to replace an Amiga unit, as was done by the original designer of the case itself.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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