Photo etch paint templates?

[stevipop]

Does anyone have any experience with the above?

Specifically, etching from brass to create something as complex as the PL Refit's saucer aztec pattern.

Would this be practical or would the brass be reluctant to follow the curves of the hull?

Is it as easy as the following?;

1) Print design on acetate
2) Spray brass with Photo-Resist
3) Place brass under acetate then glass over top
4) Expose to UV
5) Develop
6) Etch with Ferric Chloride

Or would laser cut be a better option with, say, 0.25mm plastikard?

What I'm trying to do is create templates that will last more that one paint job. I've created an aztec pattern in AutoCad that uses four layers - a small segment example is shown here.

I've created the file in such a way that each contrasting layer can be isolated, but the thought of cutting this lot out of frisket is daunting, particularly as each slice of the saucer pie would require 4 templates - that's an implied 64 friskets, just for the upper saucer alone!

If I can create long lasting templates that will conform to the hull, all I need to do is create 16 per saucer half, flipping them over as I move around the hull.

Any advice on creating such templates would be more than welcome,

Steve.

[stevipop]

Kirk: "Uhura, any response from Starship Modeler on our photo etch paint templates enquiries?"

Uhura: "No Sir, there's no response"

Kirk: "That's very odd!"

[macfrank]

It would be difficult to do in brass. The brass would have to conform to the shape of the saucer, layers and stay in one piece. An easier solution might be a vinyl template. Vinyl is flexible, thin, and sticks to itself. Vinyl pattern cutters are pretty common in print shops etc; they may even take a DXF file and cut from that.

Frank

[Pat Amaral]

Walker Enterprises makes several brass aztec templates (I think they only have patterns for the saucers). You can order them from Federation Models. Click on Products then Walker Enterprises.

[stevipop]

Thanks for the replies guys.

I'm trying to avoid vinyl as a masking medium as they are a one shot deal. I want to be able to reuse the templates at least four times and have the flexibility of reversing them, which is why brass appeals.

Having them stay in a one piece won't be a problem due to the nature of the aztec pattern.

Thanks for the link Pat. I remember these being the inspiration for using brass templates on the PL. I just couldn't remember where I'd seen them before

BTW, your sig made chuckle

[stevipop]

Hmm. I've just stumbled across Dave Merriman's excellent article detailing the photo etch process - not for the faint hearted!

If I were to do this on a regular basis I might consider investing in the necessary kit. However, I can't foresee me using this technique again after this project, therefore I'll investigate the laser cut option.

To be honest I can see myself ending up with a craned neck, sore eyes and aching finger joints due to cutting this lot out by hand under a lamp!

[macfrank]

Hmm. I've just stumbled across Dave Merriman's excellent article detailing the photo etch process - not for the faint hearted!

I wrote an article for Starshipmodeler with a method that's slightly easier to do.

Frank

[Kylwell]

I've experimented with using PE for masking and it's a love-hate thing. They're very re-usable, sharp lines, fine detail. Tacking them down is easily done with rubber cement, spray glue (low-tac) or tape (depending).

Now the hate.

Brass bends fine but to be flexible enough it needs to be thin, which makes steel PE better. Tight compound curve are impossible and tight curves may put a permanent kink in the metal.

Optimally you'd want a spring steel type metal, very thin, with a pre-applied stickem on the back.

[stevipop]

Frank,

Suddenly I feel like this is within my scope, particularly as the raw materials such as Press n Peel are available in the UK, which makes a refreshing change! Even more so since reading your write-up (not half as scarey as the previous read). Nicely done!

I noticed how the PE work you'd carried out really brought the "Marathon" to life. If the model hadn't been placed on a cutting mat I would've suspected you of joking when you stated she was 6" in length. 12" maybe, but 6"?!

Very impressive!

Kylwell,
Agreed on the suggestion of spring steel. Thanks also for the advice on laying them down too. If I do this I'll probably go through the hate thing quite early, but for different reasons no doubt! I've always been kinda lucky that way (not!)

Thanks again fellas,

Steve.

[lestatdelc]

Suddenly I feel like this is within my scope, particularly as the raw materials such as Press n Peel are available in the UK, which makes a refreshing change! Even more so since reading your write-up (not half as scarey as the previous read). Nicely done!

I noticed how the PE work you'd carried out really brought the "Marathon" to life. If the model hadn't been placed on a cutting mat I would've suspected you of joking when you stated she was 6" in length. 12" maybe, but 6"?!

Very impressive!

Kylwell,
Agreed on the suggestion of spring steel. Thanks also for the advice on laying them down too. If I do this I'll probably go through the hate thing quite early, but for different reasons no doubt! I've always been kinda lucky that way (not!)

Let us know how it goes. I was thinking of something similar, but not for painting, but rather as a cutting template the portals. If the original PE is done cleanly and sharp, then using it as a cutting guide (similar to those erasing shields in drafting class) to use as a cutting guide for masking out portals (or ini my case cutting them into foil being adhered to the model surface) would make them clean and consistent in shape.

In fact, that would be something I am surprised nobody has come up with as an after market detailing tool, cutting templates at the various scales.

BTW, I like your auto-cad template designs. Nice to see the individual "sub-plates" that make up the aztec pattern on the large sections defined by the deflector grid channel.

[macfrank]

Frank,

Suddenly I feel like this is within my scope, particularly as the raw materials such as Press n Peel are available in the UK, which makes a refreshing change! Even more so since reading your write-up (not half as scarey as the previous read). Nicely done!

Thanks! Also visit the Pulsar site; he has a lot of good ideas.

Someone suggested doing a double sided PE by aligning and transfering the pattern to both sides of a brass sheet. this would have to be done carefully, but it would cut down on the etch time (which isn't bad, in any case).

You could use other etchants, but the HCL + Hydrogen Peroxide is cheap. Cheap is good.

The process isn't perfect, and you may end up with less than good spots in the transfer.
Did you want to do a whole saucer's worth (which would be an impressive bit of brass...) or just segments? (like in your WIP #2) I guess if you plan the PE layers properly, you might be able to replicate your pattern in several segments.

Probably one of the hardest parts of your pattern is going to be the support for the brass bits.

Tempering the brass after etching may help it comform to the surface better, too.

Frank

[stevipop]

I'll be doing the saucer in segments. Using this method I can create the pattern in one piece per paint layer per saucer segment. If the colours lay down over each nicely, rather than having to create discreet boundaries between each colour, then I can reduce the amount of templates required from 16 down to just 8, or possibly 6.

I'm thinking of trying the method that Paul Olsen used on the original filming miniature before going down the PE route; stencils created from acetate. This will allow me to print the pattern directly onto the masking medium for cutting, which I don't mind if only 6 - 8 templates are required. Then I'll try a low-tack spray adhesive as Kylwell suggested such as 3M Craft Mount (has anyone used this before? Does it leave a residue behind? Can it be removed from the stencil easily?).

I like your auto-cad template designs. Nice to see the individual "sub-plates" that make up the aztec pattern on the large sections defined by the deflector grid channel

Thanks, lestatdelc. I struggled a little bit with AutoCAD initially but am making headway now as the experience grows. One annoying thing about the program is that it won't save the stencils in a format that Illustrator will understand

Did someone say "why not create the stencils in Illustrator?"
You've got to be joking; I hate the thing!

[macfrank]

I'm thinking of trying the method that Paul Olsen used on the original filming miniature before going down the PE route; stencils created from acetate. This will allow me to print the pattern directly onto the masking medium for cutting, which I don't mind if only 6 - 8 templates are required. Then I'll try a low-tack spray adhesive as Kylwell suggested such as 3M Craft Mount (has anyone used this before? Does it leave a residue behind? Can it be removed from the stencil easily?).

I think the acetate is a better idea - it has a much lower turnaround time.
I don't know if the spray adhesive leaves a residue - paint a test sheet of plastic with the paint type you plan on using for the base color, let it dry fully, then stick on a small acetate sheet with adhesive sprayed on it. Leave it on for a few hours, peel off and see if it left a residue or affected the paint.

Another possibility is frisket film; there are inkjet friendly equivalents.

Frank

[lestatdelc]

I think the acetate is a better idea - it has a much lower turnaround time.
I don't know if the spray adhesive leaves a residue - paint a test sheet of plastic with the paint type you plan on using for the base color, let it dry fully, then stick on a small acetate sheet with adhesive sprayed on it. Leave it on for a few hours, peel off and see if it left a residue or affected the paint.

I have been experimenting with printing on laser printer transparency sheets. These are sheets of acetate which are incredibly thin (as thin or slightly thinner than regular laser printer 24 lbs.) and hold razor sharp toner lines. These would be good for laying down paint with, but it is too thin to use as a cutting guide. I printed some up last night before leaving work, but haven't yet tried using it as a simple overlay to cut through to the underlying substrate (in my case kitchen aluminum foil).

I am hoping it will reduce the micro burring you get when cutting foil with an X-Acto blade (even brand new #11s). I have some nice easy tack, which doesn't seem to leave much residue and is much easier tack than scotch tape or masking tape. However it is still a heavier tack than Post-Its. Does anyone have a line on something more approaching the tackiness of Post-It note adhesives?

Ideally I would like to find a VERY low tack, just like post-its, in a very fine spray form to lay across the back of the laser printed transparency sheets, hich I would put on the foil with and smooth out (with Q-Tips) the back of the printed sheet. Then on a smooth surfae and new #11, cut the pattern (which should, I hope, reduce micro-burring) and give me the clean lines I get wih sciccors but with the ability to control length of cut lines in order to get the small corners and plate squares in the pattern which scissors do not allow. Then apply the Micro-Scale foil addhessive, place on kit, smooth into place with Q-Tips, then pull off the low-tack acetate carrier. Then smooth down the edges and work out and lifted areas, etc.

Have had very good results with printed laser paper in my tests, but the paper is a little too soft and too opaque to get the control over the line lengths for exactly hitting the pattern, and the softness allows some flexing as the blade cuts through, which in turn allows some minor micro-burring of the edges which catch light (if viewed under a magnifying glass) even after smoothing down (rather hard) with a Q-Tip, even with pressure close to burnishing the metal (which I want to avoid because it mars the very smooth and subtle foil grain and changes the sheen drastically of the dull side (which is what I am using as the upside of the foil).;

[Kylwell]

There is a roll-on version of the post-it not stickem, don;t know if they make a spray yet.