Master spray job

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roganjosh
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Master spray job

Post by roganjosh » Wed May 30, 2018 7:25 am

I picked up a couple of empty Master 128 cases last year. Both are very yellowed. One of them has obviously had something with a straight edge put on top such that half the case is yellow and the other cream. I suspect that such a two-tone case will not respond well to RetroBrite treatment, even multiple ones, and so am considering painting it. Given its condition and its 'spares' status it would be a harsh person who considered that a very sacrilegious act.

Search terms in this forum have produced limited suggestions for doing so; I'm therefore looking for advice from any others who've managed to achieve the look of an original Master using (e.g.) an ABS-safe spray paint. Particularly,

a) Colour: I see that someone has successfully used RAL1013 (Oyster White) for an Arc. What would be the best make/colour for a Master? The same?

b) Primer: Are there any recommendations for a primer?

c) Finish: I see that there are Matt, Satin & Glossy variants of 'ralcolour' sprays. Which would give the most natural finish (including what type of varnish [e.g. clear acrylic] if Matt is used)?


Alan

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lcww1
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Re: Master spray job

Post by lcww1 » Wed May 30, 2018 9:25 am

You could always try retrobrite first - if it doesn’t turn out well, then you can still paint the case!

I’ve retrobrited a Master case with acceptable results, but see this thread (and others on *.) for more info: viewtopic.php?f=41&t=13438

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sirmorris
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Re: Master spray job

Post by sirmorris » Wed May 30, 2018 9:42 am

I use vinyl dye to colour plastics. It apparently bonds with the plastic rather than covering it, so it doesn't chip or peel. It also doesn't affect the texture of the surface you're painting as much as a regular paint. The colour range is slightly limited though, and it's more expensive. Still worth considering imho.

https://www.vinyldye.co.uk/All-Vinyl-Dye-Color-Sprays

roganjosh
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Re: Master spray job

Post by roganjosh » Wed May 30, 2018 4:37 pm

Thanks both.
I RetroBrited both my Masters last summer and they turned out pretty well. However, they've subsequently re-oxidised, even though they've been kept away from direct sunlight. It seems they do, as some say, need a protective varnish; in effect a paint job. That's why I'm interested in exploring the direct paint route as an alternative since both methods would both seem to compromise the initial state of the case, but the paint might end up giving a better finish.


The vinyl dye approach sounds good sirmorris and, as you say, would do a good job in preserving the texture. Given that colours shown in browsers are often not representative of the actual colour, may I ask which one you think gives the most Master-like effect? I'm assuming it would be their 'Bone' shade. I'd also appreciate knowing whether you subsequently treated them with their Matte or Glossy 'add-ons' (as they seeem to call them) to get a more original-looking effect.

Alan

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sirmorris
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Re: Master spray job

Post by sirmorris » Wed May 30, 2018 4:44 pm

I've never used bone, and I'm always happy with the finish as-is so I can't be any help there I'm afraid. Sorry :(

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Re: Master spray job

Post by steve3000 » Wed May 30, 2018 5:04 pm

roganjosh wrote:
Wed May 30, 2018 7:25 am
I picked up a couple of empty Master 128 cases last year. Both are very yellowed. One of them has obviously had something with a straight edge put on top such that half the case is yellow and the other cream. I suspect that such a two-tone case will not respond well to RetroBrite treatment, even multiple ones, and so am considering painting it.
I've retrobrighted a few like this. Particularly bad are sticky labels that have been placed on the top or side of a computer or disc drive back in the 80's and protected a credit-card sized rectangle from yellowing over time - it looks awful after the label is removed...!

I just apply the retrobight mix to everything apart from the non-yellowed area and after a couple of goes the result can be surprisingly good. I'm sure I have some photos of a particularly bad disc drive I did earlier this year, will post them up if I can find...

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Re: Master spray job

Post by steve3000 » Wed May 30, 2018 5:42 pm

tn_DSCF3753.JPG
Disc Drive
tn_DSCF3755.JPG
Label gap up close
tn_DSCF3757.JPG
Process
tn_DSCF3763.JPG
Result

pcbbc
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Re: Master spray job

Post by pcbbc » Thu May 31, 2018 11:41 am

Does the use of the blonde dye also increase the double the "density" of the drive to 80T? :oops:

roganjosh
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Re: Master spray job

Post by roganjosh » Thu May 31, 2018 12:31 pm

Impressive peroxy acid job. Do you varnish things afterwards (if so what make/type). I may get the marigolds out again, however I don't wish to hijack my own thread so am still dyeing (apologies) to hear peoples' experiences with original-look paint.


Alan

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z0m8ied0g
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Re: Master spray job

Post by z0m8ied0g » Thu May 31, 2018 3:56 pm

sirmorris wrote:
Wed May 30, 2018 9:42 am
I use vinyl dye to colour plastics.
I've got a set of these that i'm intending to use on my BBC master, its going to be black with a white owl logo across the top.
I'll let everyone know how it turns out.
Acorn... lots of Acorn... http://blog.retroacorn.net

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Re: Master spray job

Post by mattdy4 » Mon Jul 30, 2018 8:45 am

Sorry I know this thread is a couple of months old now but did you or anyone else try vinyl dye?

I have a Micro ready for retrobriting but I'm leaning towards dyeing it instead as it's more permanent / even but unsure of the colour needed (white, bone etc)

roganjosh
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Re: Master spray job

Post by roganjosh » Wed Aug 01, 2018 9:58 pm

mattdy4 wrote:
Mon Jul 30, 2018 8:45 am
Sorry I know this thread is a couple of months old now but did you or anyone else try vinyl dye?

I have a Micro ready for retrobriting but I'm leaning towards dyeing it instead as it's more permanent / even but unsure of the colour needed (white, bone etc)
I decided to give it a while to see whether anyone else would chip in, and then a series of retro projects got in the way. Thanks for reminding me. I've got some Brillo Bone dye on order so I'll be giving it a whirl in the near future. I'll report back with at least a description of the result, perhaps more if I can ever get my cameras to produce something better than a blurred image.

Alan

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Re: Master spray job

Post by colonel32 » Thu Aug 02, 2018 2:31 am

How well does vinyl dye cover?

Can you do black over cream ABS, or bone over black ABS, without it looking patchy?

roganjosh
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Re: Master spray job

Post by roganjosh » Thu Aug 02, 2018 5:30 am

colonel32 wrote:
Thu Aug 02, 2018 2:31 am
How well does vinyl dye cover?

Can you do black over cream ABS, or bone over black ABS, without it looking patchy?
Their blurb says that a 150ml aerosol can will do 1 to 1.5 square metres with 3 fine coats and that it usually takes 3 or 4 fine coats to do the job. Their site shows how someone dyed a black freeview box to white with no apparent difficulty. They do warn that a lot of black plastics can have a top layer providing a sheen, and that that needs to be removed with wet and dry before dyeing.

Alan

roganjosh
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Re: Master spray job

Post by roganjosh » Tue Aug 07, 2018 12:53 pm

Here are the results I achieved using the Brillo Bone colour vinyl dye from vinyldye.co.uk. This isn't a recommendation one way or the other, it's entirely your responsibility whether you do the same. I also apologise for the photo quality - what my cameras lack in picture quality is more than matched by my uselessness as a photographer.

The first picture is how the top of my case looked before the treatment:
pre-vinyl.JPG
You can see that it's yellowed considerably apart from the left two thirds of the top surface where something must have rested on it shielding it from the sun. I prepared the case using Flash liquid to remove any grease followed by a thorough wash and then a rub-down with IPA. If you order anything from the vinyldye company they'll suggest that you buy their own such treatments instead. I used masking tape to protect the black areas.

After 5 light coats of the dye the case looks like this:
post-vinyl.JPG
The colour is creamier (darker) than a virgin Master and there is a faint ashen pinkiness to the colour hence, I suspect, the name of 'bone'. I find the finish pleasant enough. For the purposes of comparison the photo shows the untreated inside bottom of the case. That area was retrobrited a year ago and is already noticeably yellow. Tastes will vary but I find the outside finish much more satisfactory than the inside. Given that this is a dye rather than a paint you should not expect it to fill in any scratches. I would describe the finish as satin rather than glossy or matt. I think that's the closest to the original finish and I don't intend using the company's glossy or matt preparations. After drying for a day the smooth areas of the case feel very slightly rough.

The spraying went without incident. On their recommendation I shook the can (with internal ball bearing) vigorously for 10 minutes before starting. I left 15 minutes between each coat in an outside temperature of 24C. Their web site, as previously mentioned in this topic, says that 3 or 4 light coats are sufficient. A follow-up email from the company after the purchase suggested 4 or 5 instead. A 150ml can is enough to do 5 coats on both the external surfaces of the case top and the visible areas of the case bottom (i.e. not its underside), with a small amount left over. The spray contents are marked as an irritant and it reeks of toluene so you should at least spray outside and in the direction of any breeze. I advise that you wear a mask.

I had nothing to lose in applying this treatment as it was a spare case in poor cosmetic condition. It now looks rather good. I've even ordered a couple more cans to do my other Master cases if/when the mood takes me. For now I'll shift the innards of one Master into the dyed case and see how it looks after a year before doing so. Given the nature of the dye-plastic bond it ought to look the same.


Alan

colonel32
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Re: Master spray job

Post by colonel32 » Tue Aug 07, 2018 9:37 pm

Thanks for the comprehensive write-up, Alan. I think it looks great!

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Elminster
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Re: Master spray job

Post by Elminster » Tue Aug 07, 2018 9:56 pm

who Will be the first rebel and do a blue case!?

Looks good though, I never retrobrite, but dying looks a possibility if my cases ever get too bad.

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Re: Master spray job

Post by mattdy4 » Wed Aug 08, 2018 4:05 pm

Fantastic write up, thanks. Looks great too, I promise I'll try it myself soon and post B&A pictures

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