Rick L

Pressure pots don’t come cheap. Fortunately I have access to them and that’s been the only answer to reducing but not quite eliminating these pesky bubbles.

Unfortunately you’re introducing bubbles to the plastic by hand mixing. A fast curing resin will make matters worse. A pressure pot will help. Especially with a slow curing resin.

This 4 part rtv mold was formed over a RenShape master without pressure or vacuum. The resin casings (second photo and ready for primer) are cast upside down and sprued to the inside top where pressurized mixing guns shoot the airless plastic down into the bottom of the mold and push the air up and out through risers along the perimeter of the part. This resin kicks within 20 seconds after filled. The same technique can be done on a small scale by poring vacuumed resin into a syringe and pushed into a two part mold.

The mold for that tire was well made. Is that a two or three part mold?

I’m not knocking BMF. I use it. But the MIG is a great alternative to where I don’t need BMF. Such as my illustrated photo.

Hey fellas My MIG AMMO adhesive aluminum sheets just arrived from Ebay and compares well with BMF. The MIG measures about .0015 compared to .0005 Of BMF. The MIG goes down just as easily and sticks very well. There are 5- 7 3/4 X 11 inch sheets per package at under $20.00 including shipping.

It’s easier to mold with silicon rubber. A silicon rubber mold will work for whatever material you are casting with. When casting, a release agent is recommended when using polyurethane but is required if casting with silicon rubber. A pressure pot is not needed when silicon molding but helps when casting any material. Splitting the tire in half would make molding and casting easier because you would only need a one part mold if casting with urethane. The air bubbles would rise to the gluing surface. Glue the two halves together, clean up the parting line, and paint black. . A solid tire is a little trickier to mold and cast without having a parting line and sprue present. Try Smooth-On Corp for tutorials and material.

Holy (rap Bob it seems like you’re putting up a new model every week with some pretty nice detail work and you have time for honey do’s and grand kids?!! God Bless!

Go for it! Modeling takes many stages of experimenting. Even with tutorials. I hope you find the materials and technique you’re satisfied with and can share it with us.

I didn’t know Arm & Hammer gave out modeling advice!?

Agree with you Trevor. I also use clear fingernail polish for its viscosity.

Good file for the money.

Wanderful?

I wonder if it wanders?

Unfortunately, you don’t know what quality you’re going to get when ordering printed parts. Some vendors print out parts with high resolution, resulting in a clean soother finish, or step up the speed of production with low resolution, producing poor results. Low res is useless for detailed parts because you’re going to lose the detail from filling and sanding. Low res is only good for plain surfaces and still it’s a lot of work to fill. To answer your question, I have found Evercoat polyester glazing putty to work best for this application because it doesn’t shrink like other brands. May I suggest to anyone looking to purchase printed parts to check with the forums view on the merchants products. Or give a shout-out to the better vendors.

Hey Snake I for one miss your input. As a matter of fact the whole gang here on the forum wish you a happy and speedy recovery. The vote was 467 to 3. ?

The basic answer your going to get is,” it varies”. Your better off asking what technique would apply using a specific airbrush with a specific paint. That way someone familiar with your airbrush could give you a more detailed answer.

Agree with Ace. It may also help to sand the mating side of the styrene with a coarse grit sandpaper.

Spot on Steve. I’m also impressed with the interior door handles. What was your source?

That is quite impressive. Especially the consideration of clearance for paint in a snap together, working model.

I agree with with Steve and would emphasize not to skip on the primer. Light grey primer will bring out any flaws the body has before you paint. It’s better to sand out the flaws now than after you lay on the black.

Maybe get around it by ordering DA through Amazon? Although isopropyl is the closest option, it is not the same.

Well there ya go!?

What ever the technique chosen, A little trial and error would be in store. I agree with Doug’s original idea in that the bb’s would make a smooth dent. The Dremel bit would be on the rough side.

Heat the bb’s instead of the plastic. Then pour the bb’s over the cold plastic.