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Sources for Resin Casting Materials and What Brands do You Prefer..


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I'm seeking some input from guys who do their own casting of parts for themselves. I've decided to go ahead and order the materials and start learning techniques. What brands of material do you find preferable . What is the best online source for materials in the U.S.?

I'm not at this point,  looking to learn to do bodies or hoods or larger pieces, but rather engine parts, convertible tops and boots and seats, etc. I do not know how many more years I am going to have in this hobby, but in what time remains, I'd like to learn to be more self sufficient and to learn and expand my mere capabilities and abilities. I am by no means the accomplished craftsmen that so many of you guys out there are, but it is nice to work to try to improve ones self in any area of life. Post or PM me.. either works for me and thanks in advance. Gary

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http://smcbofphx.proboards.com/board/45/resin-casting

Hi Gary,

  Here is a link to a lot of my work.  Page 6 is my earliest entries.  Read them all.  I think all of my photos are still intact.  Even with photos you might still go HUH?!  You will need patience and some reasonably good equipment.  For multiple reasons you should build or purchase a vacuum chamber and pump.  You will need pressure pots and I have a thread about that too, the keepers and money/time wasters.  I try to stay with SMOOTH - ON products.  I can drive to the store located in Tempe, AZ and buy fresh off the shelf.  Making things like taillights can be a real PITA.  I have been using their 325, but they sell a TASK 9 to make these parts too.  I use TASK 8 for most parts.  I use POLYTEK PT FLEX 70 to make tires too.  How you clay up a part is important.  Most of what I do is from two piece molds.  Use the right clay and make it tight.  Get good measuring cups, small beakers are the best.  STARBUCKS has the best stirrers for mixing resin and silicone.  For most everyone they stir coffee once and get tossed, for me it is a tool to keep clean and free of resin buildup.  Mike Schnur can attest to my going crazy over a stirring stick.  You will need alcohol to keep tools clean.  I use lots of TP and paper towels.  Get a good air compressor.  BE SAFE!

While this forum gets no real posting activity, it has a lot of visits.  Today it says over 100.  While some would say I am giving away casting secrets, I will say I am helping a modeler hopefully get parts that are worth the money and buildable.  Companies post there own video and pictures to aid with success of its use.

 

Greg Wann

Edited by Greg Wann
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To start casting I'd recommend this:

https://www.smooth-on.com/products/pourable-silicone-starter-kit/

I just ordered some and have begun casting a few things. I had used this years ago, it is pretty easy to work with. It won't break some budgets. Under $55. I bought the recent kit from Blick Art, here:

https://www.dickblick.com/products/smooth-on-starter-kits/

I bought the kit with the OOMOO 30. It takes longer to set (6 hours) but it makes a mold that I believe you can use  a bit more often than the quicker setting OOMOO 25 although I can't prove this.

Greg has given many great points. I should have taken more time setting up my mold. I will redo them but I learned. Wasted quite a bit of silicone.

 Hope this helps.

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Thank you, Jim.  I would like to make another good point about mold boxes.  Don't make a mold box out of LEGOS.  My first attempt was buying a starter kit from Allumilite.  I didn't have any legos, so I bought some.  In the evening, I mixed up the silicone, poured it in and went to bed hoping for the best.  I got up the next morning.  Every seem leaked and most of it was on the kitchen counter and on the floor cured.  It was a first hard lesson to learn.  Then I started using pieces of wood, and that was much better.  Then I had to focus more and learn about mold release, this is important.  You really need to remember to spray this on the silicone surface if you are making two part molds.  If you don't then your parts will become encapsulated in the silicone because it will cure and just stick together.  I was using MANN 200.  I picked up some cans of STONER brand that says it is food safe too.  I am hoping it will work successfully.  Some casters from years ago would want you to make up some kind of goofy witches brew.  Don't be a cheap ass, buy professional products and learn to use them properly and be happy about it.  If all you end up making are parts that are only fit for the wastebasket, then your confidence in any attempt to make good parts might end up there too.  Believe me, I'm still learning.  I have attempted to do projects that have nothing to do with model car stuff, yes, I have focus issues.  When those ideas turn bad, I just have to shut the shop door and go do something else.   WOW! 148 guests on my casting link in the last 24 hours.  I think it is weird.  The forum is kind of like the movie, The World, The Flesh and The Devil.  There are only three actors in this 59 Sci Fi flick.  It's one of those end of the world movies that was pretty controversial in its day.  Harry Belafonte, Inger Stevens, Mel Ferrer stared in this film.  Anyway, I am uncertain why most all the club members of the two model car clubs here in the valley don't post here anymore.

Edited by Greg Wann
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Off and on, I've been making industrial prototypes, marketing and development presentation models, and full-scale aftermarket automotive and aircraft parts for decades.

The materials and techniques are very similar, sometimes identical to those used by aftermarket or hobby resin casters.

Two companies I've had good relationships with are Freeman and Polytek.

https://www.freemansupply.com/

https://www.polytek.com/

Freeman has an online video library, made by the people who engineer and make the stuff. It's always good to go to a manufacturer to get your instructions and how-to advice if at all possible.

https://www.freemansupply.com/video.htm

 

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Thank you for the feedback and information guys! i really appreciate  it. I am looking to make only smaller parts and really at this point, have little interest in even trying to cast anything larger than maybe a hood. However, do not think for a minute that any advice or suggestions posted here will be disregarded for I am sure that other readers will find your counsel useful. I have done some reading om different sites and I am watching You Tube videos before I spend the money on the materials, but Ii am definitely going to give this a try and see where it goes. I have been buying parts on Ebay for years and spent a considerable amount of money when it is all tallied up I suppose, but buying a $4.00 part and then paying that much or more for shipping is getting old and costly.

I am hoping  that small parts are a lot less complicated to make than complete bodies or do you suggest the added equipment ( vacuum and pressure equipment ) be used for that as well. I am talking seats, convertible top boots, engines, etc.  and I already have many parts on hand from which to cast. May I ask why you prefer Smooth on products over Alumilite? I realize that to some degree, it is just personal preference, but I am curious what is different between mold making material and resins. It seems that some casting resins are less thick when mixed than others and I can understand where viscosity can be pretty crucial as far as fine details go. I see some people on you Tube using hardware store silicone with additives for mold making and frankly, I am very skeptical as to what the results would be but I guess it is as all relevant as to what the caster feels is acceptable quality in the end products. I did automotive painting out of my shop for over fifteen years and during that time, I learned why buying good tools was more expensive initially, but in the end, a dual action sander was not failing in the middle of a job and shutting production down, often for the night. I also learned about good ( more expensive usually ) products being of sound value for reasons of ease of application and a longer life span for the finished paint work before it bleached or failed. So I understand your urging to buy good products and equipment. I do welcome any comments or information and thank you in advance. Gary

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https://www.reynoldsam.com/

https://www.alumilite.com/

HMMM. chapter one: Do you have a room that you can work in that will keep a mostly constant temperature?  I try to keep my shop at 78 in the summer heat or lower.  Having a dehumidifier will be a plus.  How you seal and store your resin when you are not using it is very important.  Despite having a 800 SF shop on the back of my property that is heated and air conditioned and has a dehumidifier there can still be problems.  The resin can still get humidity in it.  Sometimes resin is mixed and poured into a mold and it will foam up looking something like the foam sealant you fill holes with out of a pressurized can.  The resin will reach a temperature of around 160 degrees, and that is pretty hot by the way.  It is pretty scientific.  Once the two components are mixed together, you better get your butt in gear.  It does not care and it is not going to wait to start curing.  You can however refrigerate the two bottles before use,  it might get you two more minutes before it starts curing or kicking as some would say.  I suppose I should do videos but I just don't really care to be another look at me know it all guys that can't wait to be a TV star or a legend in their own minds, you know the type.  I digress, lets see....OH, I use a vacuum chamber and a Robinair 1500 two stage pump to remove moisture from my materials.  I also use it to remove air from my silicone once it is mixed.  I think it is important to be thoughtful when you read a manufacturer note that the silicone you are using does not need to be degassed.  With my experience, this is a CYA statement.  What are the parameters?  OK......for me, a body mold might be 4 inches thick.  That does not seem like much.  Once you mix the silicone components together, it will be full of air, lots of tiny bubbles.  Tiny bubbles can get trapped or settle next to the detail of your part, that is not good.  Your freshly mixed silicone based on other environmental reasons like temperature might start getting gooey pretty quickly.  If you have a lot of years of experience with paint and fixing bodies with various materials then you already know that messes will happen and there can be failure.  So while the thousands of tiny bubbles are escaping the freshly mixed silicone it is also starting to cure.  Silicone does not get hot while it is curing, I think it is refered to as cold cure silicone.  Please don't try to make some kind of pourable liquid silicone from a tube of silicone.  This is such a waste of time, money and mostly mental energy, it can be stressful too.  I use SMOOTH -ON products because I can drive to their showroom and buy it off the shelf.  If you are only doing small stuff then buy a starter kit.

chapter two:  Mixing the two resin parts together are very important.  First thing is, I detest popsicle sticks, there are too thick and too wide.  I like the coffee stirrers from Starbucks, crazy stuff huh?  Who woulda thought?  They are pretty uniform, they are made from some kind of hardwood and they don't break often.  Are you bored yet?  I thought you might be.  I prefer a 25 ML glass beaker as the walls of them are perpendicular?  What I mean is that the top is not wider than the base on it's interior circumference.  WOW! that's like professor talk.  In an attempt at a sort of wax on, wax off lesson, it is important to mix the two components with great specificity. LOL  So you will take the free Starbucks coffee stirrer in one hand, your acquired  25 ML glass beaker in the other.  Become one with the stirrer, be the stirrer!  Hold the container still and move the stirring stick so that it is scraping the edges of the acquired 25 ML beaker.  HEY!  Don't smirk and roll your eyes, this is truly important information.  It is like giving away a ancient Chinese secret.  You want to be a master caster don't you?  You do realize that all the time I have been setting here this morning I am not out in my shop doing what I am supposed to be doing, Right?  Making model car parts.  I am off work to take it easy from my kidney removal surgery.  

chapter three:

 

Edited by Greg Wann
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1 hour ago, impcon said:

 I am watching You Tube videos before I spend the money on the materials... I see some people on you Tube using hardware store silicone with additives for mold making and frankly, I am very skeptical...

1) Listen to Gregg Wann's advice. He does this stuff and is well known.

2) Take anything you see on YouTube with skepticism. There are self-styled "experts" routinely posting absolute GARBAGE INFO about car repairs, for instance, that are completely WRONG and were obviously just copied from somebody else who had no clue.

I do NOT know why this phenomenon is so common, but it's the reality of the web.

THIS IS WHY I POSTED A LINK TO THE FREEMAN VIDEO LIBRARY. IT'S PRODUCED BY THE ENGINEERS WHO MAKE THE STUFF, NOT A BUNCH OF INTERNET WANNABEES.

AND...I'd DEFINITELY RECOMMEND you use some kind of vacuum or pressure system to control bubbles. Bubbles are the most common thing that ruins backyard parts...which CAN be as good as anybody's IF you pay attention and do things RIGHT.

ALSO...I'dd strongly suggest you make multiple molds of the parts you think you only want one of. Mixing tiny batches of resin invites ratio errors, waste, and is just a PITA. If you can make multiple parts with each mix, you end up saving time and materials.

AGAIN...pay attention to Greg's warning about resin starting to kick when you're using it, and bubble entrapment...both in the molds when you make them and in the parts when you cast them.

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Just a couple more things that maybe haven't been touched on...

-Figure on wasting some time and material going in, before you start seeing usable parts.  It's not often that you'll get perfect results right out of the stall, even following the directions.  The first cake you baked probably didn't come out perfect.

-Until you get some experience, go with one supplier or brand for everything: clay, mold material, and resin.  Some clays aren't compatible with some types of mold material: use the wrong clay and the mold won't cure properly, at least in the areas near the clay.  Some resins won't cure properly in molds made from certain materials.  Even later on, it's best to stick with one source.  They made the stuff, they'll know what should be used with what. 

-What works for someone else might not work for you.  I've used the Freeman products and they have worked well for me.  I never had any luck with Smooth-on, but they're still in business and people are buying it so it's obviously not junk.  It just didn't work for me, so I went back to another product. 

-X2 on don't use Legos to make mold boxes.  Not necessarily because of leakage (I didn't have problems with that), it's that you'll end up making some molds bigger than they need to be which will use up more material.

-Resin is cheaper than mold material.  If the resin is "kicking" early, stop pouring it.  The molds are good for X number of uses, don't burn up one of them to get a part that will end up in the trash anyway.

-Look for household items that you can use to make molds.  For hubcap molds, I've got a bunch of the little plastic caps from syrup bottles.  They're the right size, they leave room around the outside of the part to make a good mold without wasting material, they're transparent so you can see if you have any air pockets around the part, and they're flexible so you can get the mold out easily.  Some vacuformed clear "bubble packs" can be used too, but those are generally good for one use only.  Those are good if you happen to have a part that fits in it, and leaves sufficient space (but not too much) around the perimeter of it to get a good mold.  For building mold boxes, I like clear plastic: you can get clear acrylic sheet material off of the bulk/scrap pile at a local plastics supplier. 

-Start with small parts and work your way up.

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Yes the freeman manufacturing and supply is your one stop shop. they also supply other plastic/resin retailers. if you go to there web sight  you will find all sorts of cool stuff you might need. i never met greg wann or seen what he makes but his advice is spot on. Delrin is real good for mold boxes as resin dose not stick to it but its very expensive.

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Greg has a lot of good advice, I read through his stuff and learned a lot. I don't cast enough to buy a lot of RTV, mostly wheels tires or engines,  so I usually go to Hobby Lobby and buy an Alumilite kit. I think they run around $30 for a kit big enough to do several small molds. With the 40% coupon, your looking at around $20 so it's a good way to start out. They have complete kits with mold material, casting resin and clay and also sell RTV or resin separately as well. 

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