Search found 18 matches

by chasd25
Sat Feb 08, 2020 10:42 pm
Forum: Construction
Topic: Has Ambroid disappeared?
Replies: 13
Views: 55869

Re: Has Ambroid disappeared?

I just use MEK -$17.00 (CAN) for 750 ml from just about any hardware store. I prefer Methylene chloride. Doesn't melt the brain as fast & doesn't give me headaches. Me too, I’ve used all kinds of solvents over the years working in prototyping, MEK and Kerosene both give me instant headaches. No...
by chasd25
Thu Sep 28, 2017 4:57 pm
Forum: Finishing
Topic: Weathering aluminum foil?
Replies: 4
Views: 13818

Re: Weathering aluminum foil?

I'd like to cover some models with aluminum foil. Is there a way to get a weathered, oxidized look (without destroying the adhesive)? Some kind acidic wash? I've never done this but have seen an article in FSM. You can boil the foil with eggshells or vinegar added to water. You'll get different col...
by chasd25
Thu Jul 03, 2014 3:12 pm
Forum: Finishing
Topic: How to cure paint that won't dry?
Replies: 10
Views: 20587

Keep us posted, I'm interested in how this turns out. Our shop paints ALOT of printed parts....going back 15+ years to the first SLA stuff, never saw anything like this happen. Never anything from shape ways, so I don't know what they are printing stuff in. We're painting polyjet parts off Objet mac...
by chasd25
Tue Jul 01, 2014 4:47 pm
Forum: Finishing
Topic: How to cure paint that won't dry?
Replies: 10
Views: 20587

Thanks guys. Chad, I did prime it with Gunz Mr. Surfacer or Primer Surfacer, which I understand is laquer based and rumored to regular Dupont auto primer in a smaller, more expensive quantity. The primer dried, so I re-sprayed and the same areas still had soft paint. That's what threw me. That is o...
by chasd25
Mon Jun 30, 2014 11:17 am
Forum: Finishing
Topic: How to cure paint that won't dry?
Replies: 10
Views: 20587

When we paint printed nylon at the shop we use either feather fill (polyester based filling primer), or a true lacquer automotive primer, Du-pont 131S.

Could try Tamiya white primer or Gunze Mr. Surfacer, both in spray cans, they are both lacquer based.
by chasd25
Fri Oct 12, 2012 9:40 am
Forum: Scratchbuilding
Topic: Cost of 3D Printing?
Replies: 20
Views: 31087

Contact John Vegher at Moddler

http://www.moddler.com/

He does ALOT of small parts for us. his quality is top notch, and prices very reasonable. Tell him Charlie at Sputnik referred you.

Charlie
by chasd25
Fri Oct 12, 2012 9:34 am
Forum: Scratchbuilding
Topic: Question about casting SmoothOn polyurethane RUBBER...
Replies: 9
Views: 13625

We cast flexible urethane elastomers in silicone molds all the time. I've never used the smooth on flexible urethanes. I believe they have some that will work in Tin based silicones though. We mainly use the BJB stuff at the shop. Great stuff, and available in just about any durometer you need. It d...
by chasd25
Thu Mar 25, 2010 3:54 pm
Forum: Construction
Topic: Smooth-On resin alert
Replies: 10
Views: 12475

I usually wash my kits down with Dawn dish liquid and warm water to remove the mold release. Works great and does not harm the resin. Using a good primer before painting is always a good idea. I use Krylon automotive primer myself. Worked in a production casting shop years ago, and we used Dawn as ...
by chasd25
Thu Oct 29, 2009 11:01 am
Forum: Construction
Topic: Smooth-On resin alert
Replies: 10
Views: 12475

Space Garbageman wrote:You shouldn't need to use release if you're casting out of silicone rubber molds, .
True, but it will help extend the mold life if you do use it.
by chasd25
Fri Aug 14, 2009 6:53 pm
Forum: Construction
Topic: Foam construction...
Replies: 46
Views: 49891

Nope, General Plastics still seems to be in business... :wink: http://www.generalplastics.com/ Your local distributor may be a different story... Great stuff, we've got a ton of it at our shop for model making. We buy the 7lb, and 12 lb in 4" or 6" thick sheets, and occasionally 24" ...
by chasd25
Fri Aug 14, 2009 6:44 pm
Forum: Scratchbuilding
Topic: Resin options?
Replies: 13
Views: 18333

If you want a "starter kit" this is a good deal: http://www.smooth-on.com/Getting-Started-Po/c4_1217/index.html it does use the OOO-MO silicon, which doesn't have very good tear strength. But for the beginner, who is just making a few parts, its fine. Once you get the knack of things, buy ...
by chasd25
Fri Aug 14, 2009 6:40 pm
Forum: Scratchbuilding
Topic: problematic resin casting
Replies: 10
Views: 12121

I also have heard if you microwave your mold for a minute or two (depending on the power of your microwave) then dust it with baby powder seems to improve the castings. Remember to blow out excess powder. If that doesn't work, I would try another resin such as Alumilite. I don't know about the micr...
by chasd25
Fri Oct 14, 2005 3:58 pm
Forum: Construction
Topic: Resin & RTV: MicroMark, SmoothOn, Polytek or Alumilite?
Replies: 34
Views: 31496

Glad it worked out for you, now the next time you need some resin, get it straight from the source, and avoid that micro-mart markup!

Foam core is great stuff for mold boxes, I build boxes out of this stuff, and use hot glue to tack it all together. Works for about 90% of my molds!

Charlie
by chasd25
Sat Sep 24, 2005 5:11 pm
Forum: Construction
Topic: Looking for renshape scraps
Replies: 1
Views: 3297

I've got some, email me at cdunton@thetarmac.com if interested.

Charlie
by chasd25
Fri Sep 16, 2005 12:34 pm
Forum: Construction
Topic: Resin & RTV: MicroMark, SmoothOn, Polytek or Alumilite?
Replies: 34
Views: 31496

Regardless of the mold life, thickness of rubber......if you've never made any models before, the smooth on silicon sampler is a good (and CHEAP) introduction to the materials. Some people HATE the OO MOO RTVs, and I'll admit, they aren't ideal for all appilcations. But they are a good introduction ...
by chasd25
Tue Sep 13, 2005 10:22 am
Forum: Construction
Topic: Easiest mold material/casting resins?
Replies: 5
Views: 5790

The 10:1 ratio rubber is pretty forgiving too. I measure by volume (I add about 10% extra catalyst) and get great molds. Yeah, I always add a bit extra catalyst. The only time I ran into trouble is when I didn't add enough!!!! I use a postal scale (cost me about $25) for measuring out the silicon. ...
by chasd25
Tue Sep 13, 2005 10:20 am
Forum: Construction
Topic: Resin & RTV: MicroMark, SmoothOn, Polytek or Alumilite?
Replies: 34
Views: 31496

Go to the smooth on website, and order one of the super sampler kits. Regardless of what you think of smooth on (I love their products, some people hate them), the super samplers are great for the first time user, for very little money. You get enough material to make a few small molds and castings,...
by chasd25
Wed Jul 13, 2005 2:56 pm
Forum: Construction
Topic: Any cheapo mold release substitutes?
Replies: 8
Views: 10042

vaseline and waz and grease remover. Dissolve some Vas. in a jar, and then brush the liquid on. Works like a charm!

Charlie