Cerakote - ceramic powder coating safe for plastics

[Vizir]

I meant, the high temperature powder coat for metallics...

[XMIT]

I meant, the high temperature powder coat for metallics...

Oh, that. This is just any regular high temperature powder coat. For example, the RAL 7030 that I used to do the F107 that is in the first picture of this thread, with more details here:

http://deskthority.net/photos-f62/ibm-4 ... 11432.html

In particular the box I have reads: Orbit Industries RAL 7030 Stone Gray. It claims that it is Super Durable and has a Fast Cure of 5 minutes at 400 F (204 C). http://www.orbittx.com/.

[Vizir]

Ah. Got it, thanks.

[Redmaus]

Think I found out what to do with my unsaver case if DV ever gets my plate back to me...

[Hypersphere]

Do you mask the LED strip or do you remove it prior to the Cerakote treatment? If you mask it, what kind of masking do you use?

[XMIT]

Do you mask the LED strip or do you remove it prior to the Cerakote treatment? If you mask it, what kind of masking do you use?

I remove it. A hair dryer softens the glue and a guitar pick or other non-metallic tool gently removes it. It tends to curl up; I try to reverse that while the LED strip is still warm and pliable.

It's a neat process but at this point I'm well convinced that vinyl dye is a better alternative. It is less expensive and therefore more accessible, and, doesn't flake off as easily. The cerakote is durable but you can scratch it off with some effort. The cerakote has a unique dry feeling but you don't really end up touching the keyboard's case very much in use.

[Hypersphere]

Thanks for your immediate reply. Your technique is undoubtedly better than mine for removing LED strips. Fortunately, I've had fairly good results with masking and painting with Dupli-Color.

The Dupli-Color company got back to me and said that their vinyl & fabric product is a coating, not a dye. Likewise, VHT said the same thing, despite the fact that they actually use a "vinyl dye" trademark. Moreover, VHT said that they do not recommend their product for hard plastics, such as keyboard cases. They suggested using Krylon Fusion, but I am not sure if it is really any different from Dupli-Color, SEM, or VHT products for vinyl and fabric.

[XMIT]

Fascinating.

We do know that most Model M keyboard casings are PVC, which is expressly on the list of recommended plastics for Krylon Fusion: http://www.krylon.com/products/fusion-for-plastic/

I don't just have a bunch of Model M shells kicking around like I did a couple of weeks ago, nor do I really have the time to try this out right now, but I'd love to see what results someone else has with this Krylon Fusion!

[Hypersphere]

I might give Krylon Fusion a try, although temperatures up here are getting to be too cool for painting. However, with global warming, the weather is erratic, so if I watch the forecasts, I might be able to seize a painting day once in a while. For what it's worth, Krylon Fusion has a few more color choices than VHT Vinyl Dye or Dupli-Color Vinyl & Fabric coating.

[Crazy Canadian XXIV]

I tried Krylon fusion on my M, actually. It looked amazing when the paint was still fresh, but unfortunately it didn't take long at all before it started to wear and chip off - right where my wrist sits when I'm playing games. Ended up stripping it off with brake fluid. The cable didn't fare much better.

Now, that said, it's possible I fucked up, since the paint stayed sticky. But I followed the instructions to the letter, and gave it plenty of time to dry on a hot summer day, so I'm not entirely convinced of that.

EDIT: Here's a picture:

Spoiler:

dllhost_2016-10-14_12-34-00.png (508.13 KiB) Viewed 3487 times

[Hypersphere]

Interesting. I have heard of plastic paint staying sticky when the paint was designed for hard plastic and used on soft plastic. Apparently, in that situation, the paint reacts with the plasticizer and it never dries properly.

Did you use any kind of pretreatment? If so, there might have been residual solvent that kept the paint from drying completely.

How long did you wait between painting and actually using the keyboard? Krylon takes 7 days to cure completely.

[Crazy Canadian XXIV]

No pretreatment. Just washed the case down a couple days prior, then straight to the painting. I did allow it a full week to dry on my coffee table before using it.

[Hypersphere]

What did you use to wash and rinse the case?

[Crazy Canadian XXIV]

Just dish soap and water. Dawn, I think. Either Dawn or Sunlight. Dried it with a towel and gave it a few days to air dry.

[XMIT]

Days?! You can get all manner of dust on there in days. I would paint ASAP.

I scrub the item to be painted with soap and water and a scrubbing sponge until it is clean enough. Then, I put on gloves, rinse in purified water, spray on Simple Green, rinse again in purified water, dry with a hair dryer and paint immediately.

This is basically the same treatment I would give to any part being powder coated.

[Hypersphere]

@XMIT: What is "Simple Green"? And what about "purified water"? Is this distilled or deionized or reverse-osmosis water?

Other than that, my procedure is similar to yours, except that I don't do "Simple Green" or a "purified water" rinse. Instead, I rinse with 70% (v/v) isopropyl alcohol. I also don't use gloves, but this looks like a reasonable precaution against contaminating the surface with skin oils.

Another difference from Crazy Canadian XXIV is that I do not use towels to dry the surface -- this could result in depositing lint on the plastic.

The Krylon Fusion instructions are as follows:

=====

Spray Painting Plastic

1. For old plastic, use an ammonia-based cleaner on surface.
2. For new plastic, use paint thinner to clean surface.
3. Lightly sand surface if previously painted.
4. Remove dust with a tack cloth.
5. Let plastic surface dry.

Apply Krylon® Fusion for Plastic® spray paint according to the directions on the can.

=====

I suppose we would be painting "old plastic", so an ammonia-based cleaner might be in order. Which vintage keyboard cases are painted? For those that are painted, it appears that light sanding should be done. I usually do wet sanding, which would then involve removing dust by rinsing rather than by using a tack cloth. I would then rinse with distilled or deionized water and/or 70% (v/v) or 91% (v/v) isopropyl alcohol and air dry or blow dry. I think that the same procedure could be used with VHT "vinyl dye", SEM vinyl coat, Dupli-Color Vinyl & Fabric coat, or Krylon Fusion.

[fohat]

@XMIT: What is "Simple Green"?

Spray Painting Plastic

1. For old plastic, use an ammonia-based cleaner on surface.

2. For new plastic, use paint thinner to clean surface.

My wife loves to use "Simple Green" on everything, and I hate it. The smell makes me want to throw up and lingers interminably.

The Simple Green web site assures you that it is "residue-free" yet there is this:

"Seems that the U.S. Army has spent several years and a great deal of $$$ to determine that military equipment that was cleaned and serviced with Simple Green, corroded and failed at a rate significantly faster than if it had not been treated at all. In fact, using Simple Green on the equipment actually encouraged the development of rust and the deterioation of the steel.

He explanined that being a metasilicate, the residual Simple Green residue left behind after cleaning actually attracts water molecules, acting just like the packages of silicate dessicant that you find inside electronics packaging. It's crystaline structure also means that like salt, as more moisture is attracted to and becomes attached to the residue, the crystaline structure grows, compounding the destructive effect by attracting even more moisture and encouraging more growth. All of this growth and expansion can actually push joints and seams apart as the structure grows, adding another element of destruction to the equation."

Thank you very much for the ammonia/paint thinner (presumably they mean "mineral spirits" which is what generic "Paint Thinner" in the US usually consists of) specification.

Personally, I have had pretty good results with soap and water scrub (I prefer powdered laundry detergent such as "Charlie's" or "365" with about 10% "oxi-" additive), rinse very thoroughly, shake off, and air dry.

Otherwise, alcohol (91% isopropyl is common now) or denatured is probably better but may be unnecessary.

[XMIT]

I use distilled and reverse osmosis water interchangeably. I'll use distilled when I need things particularly clean for a final rinse.