robdebie

100% agreement with what you write. Can you agree with the modification as sketched in the previous posting? Rob

You could phrase my initial question like that, yes. Based on the responses so far, this is what I currently have in mind. I want to sand off half of the 'strange detail' and retain that as a simulated gasket. Next I would add a relatively thick flange to the crankcase halves. The crankcase gets lifted by 2-3 mm. Would you agree with this approach? Regarding the fuel cap on the base of the other model: that fuel cap was originally the turning switch for the electric motor. I don't see the base as a fuel tank, but one could. I removed all traces of the motorization on mine, hence the difference. Rob

It's a crazy phenomenom indeed! Could you, for the sake of science, try water-based acrylics over all these paint layers? Theoretically that should stop the bleeding. Rob

Bill, Greg, Ken: many thanks for all the responses and insights! It's clear that all of you 'see' a flange, and the photos support that idea strongly. Thanks for searching and finding the photos! The modification to a 'flange' type construction wouldn't be too much work actually, if I would do the filling with Apoxie Sculpt, without sanding. But the thing is that I made a custom paint mix from three colors, to create RAL 6011 'machine green'. And as Murphy would have liked it, I just ran out of that paint. I need to do some hard thinking.. Bill: I fully agree with your comment of 'what happens when the tooling designer doesn't understand the function or real-world construction'. In my view, this model is full of these problems.. Greg: I think the model represents a theoretical teaching aid. I never found a picture of a single cylinder engine that resembles the model. Rob

I'm building the 1972 vintage Airfix single cilinder four-stroke engine with cutaway sections. Here's where I'm at, nearly done: I want to glue the crankcase on the foot, but I just don't understand the detail that Airfix molded on the foot. Here's the connection between the crankcase and the foot. Is this supposed to be a clamping ring? Or is it a flange of the crankcase halves? Or is there a simulated gasket under the clamping ring? Should I fill the gap to make a smooth transition to the flange / clamping ring? What do you think? Any help is welcome! Rob

The simplest solution I see is to rename all the photos to the actual model's name. Then that file list (folder / directory) is your database. Rob

Try the 'Donn Yost' or 'Andy X' method! I found it some months ago, and it worked extremely well for me. Here are some test pieces - so far it worked with all brands of model enamel that I tried. The method is simple and easy, give it a try! Rob

I built the 1/96 version two years ago, and made a full build report, with details of the paints I used: https://robdebie.home.xs4all.nl/models/lm.htm With this as the end result: For the 'wrinkled' isolation blankets, I used kitchen aluminum foil. If you have an airbrush you can use yellow and red paint to mist over the foil to create the required three colors. My build report includes a link to the David Weeks drawings, that contain a ton of information. For the fine-grained material, another modeler used a mortar repair material, to repair brick walls, and that looked really good - just the right mix of fine material and 'boulders' if applied with a spatula. Plus probably the right color, boring medium gray. Here's a picture of the stuff I'm talking about: Rob

Interesting! You're the first to point out the differences in AndyX's video and Donn Yost. For the moment I'll continue with the 'Andy X' method, it works really well for me, and it is simple and quick. Rob

There's a recent thread on this. My contribution was that I read a paint technology book that said that the typical red dyes in plastic are easily dissolved by paint thinners. and then move to the paint surface. I would use a water-based acrylic as primer, and then be very careful with the next layer(s) that contain solvents. Rob

I remember reading in a book on industrial paint that the red dyes for plastic are notorious for being able to dissolve in paint solvents, and thus moving into the paint itself. To me it sounds like different paint solvents could be the answer. Like using a waterbased acrylic paint instead of (say) an enamel with added white spirit. But that's just a hypothetical example. Rob

You probably can, but I was responding to the 'Hopefully, the Paasche H will fill in and smooth everything out' part - that sounded like a bad idea. But you can try! ? Rob

That part sounds like a recipe for disappointment. Get your parts smooth by other means, before you start applying paint. Or use a fresh model. Rob

Thanks! It seems I'm doing it the right way ? Rob

Very interesting! The H3 already shocked me with its paint flow, so I was almost afraid to try the H5 needle ? But if your experience is so good, I must give it a try! Rob

I've been working with my new Paasche H for just a few weeks, but I would not hesitate to use it for something large. In fact it would be my clear first choice from a total of four air brushes (Badger 200 and 150, Iwata HP-CS and Paasche H). But maybe you're saying you would use the H5 needle? It came with the set I bought, but I haven't tried it - I'm still getting used to working with the H3 needle. One thing I don't like so much is that the turning part of the needle set has no markings to show how much you opened it. As an interim solution I painted two stripes on it. For the Donn Yost method, I use -0.8 turns while applying a color coats, and then ~1.5 turns for the wet gloss coats. Rob

If you can regulate it in the 15-30 psi range, it should be suitable I guess. You may need an adapter to connect the airbrush hose. My Paasche H set came with a hose that has a fairly large connector, roughly half an inch. I looked for a designation but could not find one. Rob

Solvents could attack the plastic, be careful there, and do a test first. I've had great success using NaOH aka lye aka caustic soda in combination with an ultrasonic cleaner. But it only works for enamel paints. See here for the full story: https://robdebie.home.xs4all.nl/models/ultrasonic.htm Here's a truck cab that I stripped recently, almost spotless without any effort: Rob

If painting bodies is your main goal, check this thread about the Donn Yost method: http://www.modelcarsmag.com/forums/topic/164406-just-discovered-the-donn-yost-paint-method-one-question/ The Paasche H is a key ingredient is you ask me. It has a *rough* instead of a *fine* paint atomisation, and that's what you need for that particular purpose. I think you can buy a Paasche H set for ~50$ in the USA, I paid 60 euros in the Netherlands. I don't think you'll find a decent compressor for the remaining money though. One model that seems to be sold everywhere and under many brand names is the 'AS18' type. I think it's a Chinese clone of a Badger original. I've worked with it, and it's reasonable. The constant on and off switching is pretty annoying, I'm used to a silent Sil-Air 20 with a buffer tank. I think you can find the AS18 for ~70$. The combination would give you a reasonable start. Rob

The curing inhibition only applies to addition cure (platinum) silicone rubber. The list of cure inhibition materials is quite long. The following materials are listed by manufacturers: - condensation type silicone rubber (especially its tin-soap catalyst) - unsaturated hydrocarbon solvents - sulphur (in vulcanized natural and synthetic rubbers) - phosper - epoxies containing strong amine catalysts - isocyanates of urethane resins - tape adhesives - metallo-organic salt-containing compounds (especially tin salts and heavy metals) - plasticizers in plastics (especially vinyl) - some epoxy and polyester resins - nitrogen containing materials - some modelling clays - solder flux - wood - leather - chlorinated products (such as neoprene rubber) But still I very much prefer this type over condensation cure (tin salt) silicone, even though the latter is cheaper. I just don't like the shrinkage of condensation type. The amazing thing is (quoting from manufacturer, Shin-Etsu I think) is that the shrinkage never stops! Rob

Another suggestion: watch a few Robert Tolone videos on resin casting. https://www.youtube.com/channel/UCPA1NCFqYebL6RBW5-bnOrg/videos?view=0&sort=dd He's always trying challenging objects to cast. Rob

One comment on the need for a release agent with two part molds. In the past, all silicone rubber types that I used would stick like crazy when poured on a cured piece (i.e. first mold half). So you would need a release agent. But with the 10 Shore-A type that I'm currently using, this is no longer the case. With a little effort I can peel the second pour from the first. Therefore: check first for the adhesion, it could save you some work. Rob

For the record, I used Humbrol and Revell enamels. I get the impression the method works with whatever enamel paint. Your question about the second color application wrinkling the first color due to the lacquer thinner, that's a good one! I hope to find out soon. Rob

What you describe comes close to the method, but its not 100% the same. I would suggest watching the video linked in the first post, if you want to see it. Rob

So true! Misting the paint is NOT the way to a gloss coat. I learned that through experiments years ago. But with a heavy coat you get in the danger zone of runs. It seems that the lacquer thinner avoids that. Rob