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Author Topic: Ruling pen with dope?  (Read 689 times)

Offline Tim Wescott

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Ruling pen with dope?
« on: April 30, 2022, 09:02:30 PM »
Has anyone drawn panel or other lines with dope and a traditional ruling pen?  I'm not talking about a technical pen, but the old-style all-metal ruling pen (see the picture).

I asked about using a Rapidiograph or other technical pen with dope, and the answer was "no, it'll clog immediately".

I need to draw some thicker-than-usual lines on a scale plane, in the same paint color as the plane.

I grabbed a ruling pen out of my 1940's-style drafting set and tried some dope on a handy surface.  The test worked out really well.

So -- am I missing anything?  This seems like a perfect solution to me.
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The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Dan McEntee

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Re: Ruling pen with dope?
« Reply #1 on: April 30, 2022, 10:13:47 PM »
  Just guessing on my part, but I think if your simple test worked OK, you are in the ball park. I would do another simple test on a sheet of shelf paper that will replicate what you want to do on the model. That will tell you how far you can go on a "dip" of dope. The viscosity of the dope may be important, and I'm again guessing that using it un-thinned or or a 75-25 dope to thinner mix will flow like you want. Unlike ink lines, you won't get a second chance by just wiping the line away with some alcohol. I would shim up your ruler edge and anything else you might use as a guide also. Several year ago I bought a "pin striping tool" that I can't remember the name of. It is a small jar with a selection of applicator wheel that you attach to it for the width you want. The guy selling them in the booth told me before I even asked that a lot of guys were using Brodak dope in those. I think it was named Bejur or something like that. I know I still have to but not sure where it's hiding at this time. It or something like it may be what you need, but I would give the old style ruling pen a good try first.
  Type at you later,
  Dan McEntee
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Online Ken Culbertson

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Re: Ruling pen with dope?
« Reply #2 on: May 01, 2022, 08:06:00 AM »
The viscosity will matter.  India Ink is water based with a kick ass pigment.  It flows easily.  Dope pigment is not as opaque when thinned to flow like water does.  India Ink is absorbed into the paper, dope will try and form a chemical bond. My guess is that it will work for some colors and not others depending on how much (if any) you have to thin the dope.  If you don't have any experience with the old pens, block off a week or so to practice.  It is a long lost skill that does not happen over night.  Ink is easy to clean on a filled smooth surface.  Dope will not be due to the chemical bond.  My advice would be to let the error dry and carefully scrape it off with a #11.

As an alternative, and I have not used this yet for panel lines on a real plane, but I have tested it and planned to try.  I used a fully painted (with my trim color) sheet of inkjet vinyl decal sheets, same should work for slide off but you will have to be super careful with the thin lines.  I razor cut strips to 1/16 which may be too wide for what you are doing and laid them on like striping tape.  Thinner than tape and pretty much blend in (much better than tape) after a coat of dope.  Just a thought.   You may just have to mask....Agghh. If you do, Tylenol Arthritis strength does work for headaches.

Please let us know if the pen works and what colors it worked with.  I have drafting experience as a young'un and I might like to give it a try.

Ken
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Offline Tim Wescott

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Re: Ruling pen with dope?
« Reply #3 on: May 01, 2022, 08:31:45 AM »
It's for the scale Ercoupe that I'm building, so the answer will show up there.  Good point about practicing.  I'm thinking I'll shoot a coat of clear on the area first, to present a less porous surface for boo-boos to sink into and thus require less scraping/sanding to fix 'em.

I have several sheets of waterslide decal material -- I may cave and just use that.  Or if my wife approves it, a red sharpie, but I suspect that'll just not be right.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Online Ken Culbertson

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AMA 15382
If it is not broke, don't fix it.
USAF 1968-1974 TAC

Offline Tim Wescott

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Re: Ruling pen with dope?
« Reply #5 on: May 01, 2022, 09:31:05 AM »
Just a FYI

https://www.hobbylobby.com/Art-Supplies/Drawing-Illustration/Calligraphy/Red-Dr.-Ph.-Martin's-Bombay-India-Ink/p/6695

Ken

Y'know, the reason I haven't been going there is that just because it says "red" on the bottle, it's not necessarily the same red as a can of paint that says "red".

But then, I've already decided that for the plane, I'm just going to use a can of dope that says "red", rather than moving heaven and earth to get the same exact shade as in the pictures.  (I'm not what you would think of as a serious scale competitor).

So maybe I should just use that -- thanks for making me think along lines I should have been on all along.  Especially since there's a Dick Blick's in Portland, and they probably have a rack full of inks suitable for the pens I have, and pens suitable for whatever.  I can paint a test swatch of red on something, and take my wife to help with selection (she sees colors better than I can -- I'm partially color blind, which makes my color combinations interesting, sometimes).
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline kevin king

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Re: Ruling pen with dope?
« Reply #6 on: May 02, 2022, 04:41:21 AM »
Depending on the size of the line you want, you could also get really narrow width Fine Line masking tape, lay down the the tape where you want the line, add another tape top and bottom, then remove the center one and then spray on the color you want it to be.

Offline Howard Rush

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Re: Ruling pen with dope?
« Reply #7 on: May 02, 2022, 01:32:40 PM »
Thicker meaning taller or wider?

I told you how I'd do it, but you were afraid it would be against the rules.  Jimby recommends "paint pens", as opposed to ink pens.  If you want to use decals, I found a really good system.  Call me.

There's a really good art store across the street from the Thai restaurant.  Is that Dick Blick's? (Reminds me of the English joke, "Is this Cockfosters?")
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Making combat and stunt great again

Offline MikeyPratt

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Re: Ruling pen with dope?
« Reply #8 on: July 31, 2022, 09:40:24 AM »
Hi Guy’s,
Using the old ruling pins is a lost art for sure.  My old friend Claud McCullough at Sig could use then with ease, I watched him do this many times.  He would take the color of dope he wanted and mix some thinner, retarder, and a few drops of methanol until it flowed freely through the pin onto the surface. 

He showed me how to do this when I was building one of his old time FF models, they were painted red & black with silver pin stripping.  He applied the silver pin stripes with the rulIng pin.  Also, he never told me how much to thin the dope but kept adding thinner/retarder/alcohol until it flowed smoothly from the ruling pin, I sure miss Claud he was a good friend and mentor.

Later,
Mikey

Offline Tim Wescott

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Re: Ruling pen with dope?
« Reply #9 on: July 31, 2022, 01:43:23 PM »
Mikey -- that's really cool.

I'm not so sure about the "lost art" part of it -- I picked it up pretty quickly.  As someone pointed out, if you do it with dope you have to get it perfect the first time -- that's a bit rich for my blood, but I think I'll use them for applying india ink next time around.  If I do a few planes without having to wipe off any India ink mishaps, I may consider using dope.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.


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