Rick L

Most resin castings are cast with silicone based release agents. Soapy water or isopropyl alcohol works fine for most.

Sounds like a tape problem to me. Some masking tapes are too aggressive. Especially when left on too long. Tamiya tape burnished on the edges works very well.

Naphtha and toluene on the msds. It’s hot.

A few tips on reducing bubbles Stir slowly and don’t use popsicle sticks. They are too porous and will introduce bubbles. Use a mini plastic spatula or plastic sprue. If it has a long working time, warm the two parts in a water bath this will make the plastic less viscous. The lower the viscosity the easier bubbles rise. If using the “squish” method, don’t pour in the middle of the mold and slap the cap on. Pour it down the side wall of the mold until you have the desired amount. An ultrasonic cleaner will also help bring bubbles up on less viscous plastics. Place the cup with plastic into the cleaner tray and surround the cup with water. You can buy an inexpensive cleaner at Harbor Freight. When you wind up with micro bubbles at the top of the plastic, wave a bunsen torch or breath heavily over it. The carbon dioxide will break them up. I’ve never tried this myself but am told that a spritz of alcohol on the surface of the plastic will also remove those micro pests.

Bummer. You would think they’d use a more reliable material for fragile parts.

Ditto!

It amazes me what Jim Hall had accomplished by 1966 at 31 years old.

I vote for striations.

The higher the resolution on the printer the better the quality of the surface. Think of it like pixels on your digital camera or your tv screen the more dots per square inch the sharper it will be.

When using putty try applying it in thinner layers. This will allow the solvents in the putty to evaporate quicker without attacking the styrene too violently. When using polyester resin use the same process to allow cooler curing between coats to prevent warping.

Try McMaster Carr industrial supply. They have an array of different blades with dimensions that may work for you. Also check under their scalpel section.

He said two part epoxy. He did not specify its curing time.

Agreed. His apprenticeship didn’t last long. 😆

That harmless looking Dremel tool has created some interesting industrial accidents. A fellow model maker was cutting into a handheld polystyrene tube with the spring steel saw blade and instead of cutting through, it cut into, then grabbed and spun around the tube then around his thumb. YIKES! Throughout the model shop. Bloodiest mess we’d ever seen.

Now THAT’S frugal.😆

Obviously there is no advantage to vacuum casting with fast curing plastic.

You are correct my friend. I did not go back to look at the set up in the video and assumed it was the supply end.

3M makes static mixing nozzles to alleviate the problem of introducing air into the plastic. And WOW that pvc pipe at 100 psi. over time is going to be scary.

Another contaminant not mentioned that all modelers should know is a steam boiler. I would imagine that most modelers paint in their basement and a steam valve can spew off oil and whatever before closing. Creating a bad painting environment.

Strip it.

I would think another advantage is that, once set, there would be minimal or no shrink after sanding and primer.

Our Rube Goldberg constructions were the best part of racing.

Slot car racing was huge back then. Slot car centers popped up everywhere. I’ll never forget my brother telling my mom to take a lap with his 1/32nd scale Cox magnesium chassis converted with a plastic model car VW bug. It was at Modelville Hobby in Framingham Ma. A big banked Sovereign track. Most cars hung on the bank by centrifugal force except my brother didn’t know anything about top heavy cars. Well, mom hit the throttle, full blast and didn’t know anything about breaking. That car went off that bank like it was slung off by a jai Alai wicker right into the pit stop area 30 ft. away. It was a quiet ride home.😆

That’s what I assumed tinted colors were designed for. Applied correctly lacquer will not craze styrene unless it’s applied heavily.