# 3D Printing > 3D Printer Parts, Filament & Materials >  Projet 1200 - FTX Cast Burnout Tests

## bford903

I just received my shipment of FTX Cast for my Projet 1200. I'll be posting the results of the printing and casting tests here. 

First print



The material feels much softer, more like wax, than the FTX Green. My wax pen had little to no effect on the material and injection and sprue waxes have a little trouble sticking to it. 

The Auto-supports generated by the software are very thick and are difficult to remove. Recommend that you create your own supports on the model prior to printing. 

First Test:
Satin-Cast Investment (gypsum)
Standard Wax Burnout - 6hr
Mix for Standard Castings


Result:
Unusable. Investment breakdown. Heavy porosity. Pitting. Bad Surface. Reminds me of earlier casting tests with the FTX Green. Complete failure.

This result was expected, but the casting looks much worse than I anticipated. I think the poor result is mainly due to a curing issue. Maybe a cleaning issue as well. I'll extend cleaning procedure and curing time for next one and repeat test with Plasticast investment. Time to step it up. 

Not even my school castings were this bad.


 :Frown: 


I also put one in the oven by itself (no investment) to watch the reaction. Very similar to FTX Green. I believe they call that a "Temperature Differential".

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## bford903

Second test:
Plasticast Investment
6hr burnout
Heavy Castings Mix

Result: Unusable. Same result as before but less severity. Failure. 


I still think this is a curing issue. I believe there is still uncured resin inside the model causing the temperature differential which causes the model to expand which is damaging the investment. 

I have a few more models in various stages of curing and I'm starting to notice a significant color change as the model cures. The initial color is a light yellowish-green and changes to a almost white color with a tinge of purple (this is noticeable on the first prints). The color change is occurring throughout the model from the outside in. I think curing time should be measured in days not hours. 

Next test will be with Plasticast and mucho extended curing time. 

Anyone know if there's a patron saint of jewelry casting?

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## curious aardvark

so is your printer fff or sla or something else ? 

Sounds like you might be a candidate for the new wax filament. Yep it's pricey - but if you're making jewellery then that's a factored in cost anyway. 

Won't work if you're using an sla machine though.

(checks) ok sla machine. So that won't help. Shame.




> *Micro-SLA 3D printer* The ProJet 1200 is designed for small, precise, detail-rich parts and  casting patterns. It has excellent precision and surface smoothness,  printing 30 micron layers at a 585 dpi print resolution through enhanced  LED DLP technology. The ProJet 1200 is ideal for jewellery, small  volume dental and electronic applications. 
> 
> *Fast print and network ready* The ProJet 1200 is a fast desktop 3D printer, printing at 14mm/hour  vertically, equivalent to 5 rings per two hours or 12 dental wax-ups in  one hour. It is network ready (via Ethernet), allowing multiple users to  access the printer.
> 
> *VisiJet FTX Green material, ideal for detail and castings* The ProJet 1200 uses an all-in-one, easy to fit cartridge ensuring consistent high part quality. It uses VisiJet FTX Green material  which is a durable and rigid material, tailored for plastic prototyping  and casting patterns. VisiJet FTX Green burns out cleanly for ash-free  castings.


Maybe it's your burnout temp ?

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## bford903

It might be the burnout temp but I don't think so. We're ramping to 1350 degrees F (732 C) and holding for 2hrs. Approaching 1500 degrees F (815 C), the investment will start to break down. The material turns black and starts to burn at 800 degrees (see picture above). In previous tests, extending the time at max temp didn't really improve the casting. Look at the letters in the picture; you can see the rough edges where the letters broke off on the inside of the mold as the material was expanding. The porous outside surfaces are most likely caused by residual ash residue in the mold.

I have to get this job done and out the door pronto so I'm moving to phosphate-bonded investment. I'll experiment with gypsum investments after I finish this one.

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## bford903

Fully cured piece. The green shade is completely gone.

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## bford903

The previous piece came out excellent but I didn't get a picture after it was completed. After it completely cured, used Plasticast and an 8hr burnout and it came out great.

Here's the test using phosphate-bonded investment. Came out better, but not quite there. This is definitely a curing issue. Larger pieces are concealing uncured resin, and since the new material is more opaque than FTX Green, curing time may need to be extended. Thinking about building an external curing chamber.

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## locator

Wow.. You are so great. I'm using projet 1200 with cast. I have some questions.
1. Support is too large(despite i set this small size ) and I think that software fixed to largest size. you too?
2. How many hours does it take to fully cure? (average time in bulit-in chamber)

I think that projet 1200's built-in curing chamber is crap. It works only 10min and it couldn't cure all side of printing. We need to use a more strong external chamber.

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## bford903

> Wow.. You are so great. I'm using projet 1200 with cast. I have some questions.
> 1. Support is too large(despite i set this small size ) and I think that software fixed to largest size. you too?
> 2. How many hours does it take to fully cure? (average time in bulit-in chamber)
> 
> I think that projet 1200's built-in curing chamber is crap. It works only 10min and it couldn't cure all side of printing. We need to use a more strong external chamber.


Oh thank you. 
1. I create my own supports in Rhino and attach manual supports to the bottom of each in Geomagic. You're absolutely right. Even the small supports in Geomagic are too big. When I tried to remove them, sometimes the piece would break. My supports range from 0.6mm to 1mm in diameter and are tapered at the tip for easier removal. 

2. Smaller pieces seem to cure completely after 2-4 cycles in the curing chamber. Larger pieces take much longer (I have a ring in there right now, and at the time of writing this it's on its 6th cycle). Keep curing the piece until the green shade is completely gone and you'll minimize expansion during burnout. The color changes to white, then a light pink. I'm looking into building an external curing chamber as well. Something I can setup to cure overnight. 

Good luck to you and if you ever need any help, please feel free to contact me.

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## bford903

It was indeed a curing issue. I cured these until the green shade was completely gone, and used Plasticast (heavy mix) with an 8hr burnout and they came out very well. Little to no porosity. 

With the FTX Green, the cured piece was strong enough where I could file all of the grow lines off before casting. The FTX Cast is much more brittle so I'm apprehensive to start filing on it. That's why the surface is a little rough on these.

IMAG0492.jpg

IMAG0494.jpg

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## bford903

Been having issues with incomplete prints. Random areas seem to be delaminating. Seems like it's sticking to the bottom. Not sure why this is happening or how to fix it. This is occurring to more than half of my prints. Large or small supports don't seem to make any difference. There doesn't seem to be any way of changing things like print speed, layer thickness, etc. in the software. Not sure what to do. 

IMAG0507.jpg


EDIT: No updates on software or firmware recently that would have caused it.

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## tato887

hi  i buy a projet 1200  and iam trying to use to cast some pice but i cant how can i  do sorry my english is not to good but i need help
 another thing that hapend to my is that the cartiged broke insede the projet  and now i am having problems printing new pices

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## bford903

To cast the material from the Projet, you'll need phophate-bonded investment (investment used for casting platinum). It comes with the powder and the binder for mixing. 

1. Weigh the appropriate amount of powder and binder for your flask size. Instructions should come with the investment.

2. Mix and vacuum. (Ideally you'll want a mixer that will pull a vacuum and mix at the same time, but it's not required.) *NOTE* Platinum investment rises very high in the vacuum and may spill over. I recommend wrapping masking tape around the top edge of mixing bowl and flask to prevent spillage. 

3. After mixing and vacuuming, pour mixed investment into the flask and vacuum again to remove as much air as possible.

4. Let flask sit undisturbed for about 20-30 minutes. You'll notice that as the investment is curing, heat is produced and at the end of the 30 minutes the flask will be hot and steaming. 

5. Immediately put the flask in the oven preheated to about 1700 degrees Fahrenheit and leave for about 1.5 hours. (Rapid-burnout technique works with 3D-printed resins because it heats the resin so quickly it does not have a chance to expand and damage the mold. Gypsum-bonded investments will not work using rapid-burnout technique.)

6. Ramp down to casting temperature, about 800-900 degrees Fahrenheit, and leave for about 30 minutes. 

7. Cast normally using a centrifugal casting machine. If you're using a pour vacuum caster, you'll need to scuff up the closed side of the flask a little to allow the air to flow through before pouring. 

8. After cooling to point where you can handle the flask, I typically use a hammer to break the large chunks of investment away and use a Platinum Investment Devesting Solution to remove the rest. Quenching will not work. Make sure you have adequate ventilation before using devesting solutions. 


If your cartridge broke inside the machine, you'll need to clean it thoroughly before printing. If you're still having trouble printing after cleaning, you may need a replacement machine. I would contact the people you purchased the machine from for further instructions if the machine will still not print after cleaning. 

A few tips for working with FTX Cast:
1. To cast with FTX Cast, make sure the piece is thoroughly cured before investing. I typically have to cure the material for 6-10 cycles before it's fully cured. Uncured resin will cause porosity in the casting. 
2. Add your own supports to the piece in the CAD software to make removal of the supports easier. The auto-generated supports are very thick and can break the piece after it's printed. 
3. The cartridges for the FTX Cast are awful. Put some electrical tape around the seam of the film on the bottom of the cartridge to prevent leakage. 

My recommendation would be to use the FTX Green material and use the above method for casting. The FTX Green produces very high-definition models that print very well and are suitable for rubber molds as well. I make rubber molds directly from the 3D-printed piece when the situation calls for it and it works very well.

Using FTX Cast, 60-70% of my prints are failures. They keep sticking to the bottom of the glass and the piece breaks during printing. Difficult material to work with.

Good luck and feel free to contact me if you ever need any help.  :Smile:

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## tato887

thanks very much for your help i really appreciate your answer  , i will buy *Kerr Platinite, 36 KG Drum to try what are you saying to me . 
when i cast some pice i will post
what brand of investment you recomend to me to cast with the projet 1200

thanks again*

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## bford903

I was using an investment called Whip Mix Formula 1 which is typically used in dental applications.

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## bford903

Rant incoming  :Mad: 

I finally had a little spare time to resume testing yesterday so I made a few prints using a relatively simple band with some engraving bits on it. First print had five rings stacked together on the build platform and the second print had only one. I used the Auto-Supports generated in the software. First one printed but I wouldn't call it usable. There were too many on the build platform and they kinda fused together. Second printed but had some weird issues. Missing spots randomly peppered throughout the piece. 
mms_img1999644911.jpg
Here it is in the software before printing. (Notice the supports in the program, and the same supports on the actual piece. Big difference.)
PrintTest.jpg


This morning I came in to resume testing. Checked the machine before starting and found this:
mms_img1273807451.jpg

Caused by...
mms_img-62897976.jpg

You can see where the film has separated from the cartridge. This has been a common occurrence with this new material and the cartridges. I believe this is happening during printing as a lot of my failed prints end up firmly stuck to the bottom of the vat. I think the piece gets stuck to the flim and tears it from the cartridge as the build platform lifts up causing the resin to leak out. As usual, 3D Systems says it's my fault by not loading the cartridges correctly and failing to clean the machine regularly.

I'm done with this material. Failed prints 60-70% of the time. Leaking cartridges. Extended cleanup of your piece from the mammoth-size supports required to get a decent print. Mucho-extended curing times if you want any hope of a good casting. Failed castings 60-70% of the time. The whole purpose of this material was to make burnout easier, and from what I've seen, it's just not there yet. As far as my testing goes, I've seen all I need to. 

Verdict: FTX Cast is a waste of time and money and anyone who has the Projet 1200 should stay away from it for all the reasons I stated above. If you have a Projet 1200, use FTX Green and make rubber or silicon molds from the printed pieces. Or, if you are already set up for platinum casting, print with FTX Green and cast using phosphate-bonded investments with the rapid burnout technique. This method should get you high-quality prints and castings from your Projet.

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## G.EVE

> Been having issues with incomplete prints. Random areas seem to be delaminating. Seems like it's sticking to the bottom. Not sure why this is happening or how to fix it. This is occurring to more than half of my prints. Large or small supports don't seem to make any difference. There doesn't seem to be any way of changing things like print speed, layer thickness, etc. in the software. Not sure what to do. 
> 
> Attachment 5856
> 
> 
> EDIT: No updates on software or firmware recently that would have caused it.




hi
you can try magic and fix your naked edge or anything else that may cause if fail //// maybe its not bolin

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## bford903

> hi
> you can try magic and fix your naked edge or anything else that may cause if fail //// maybe its not bolin


Magic, eh? Been a while since I talked to the coven. I wonder if they still have my wand... :Stick Out Tongue: 

Pretty sure there aren't any naked edges or bad surfaces on the model. Usually, if there's a bad surface or naked edge on the model, the problem areas occur in the same spot every print, in the vicinity of the bad surface or naked edge. I don't think that's it but I will double-check with a few third-party programs just to make sure. 

Bolin? Do you mean Boolean? Yes I used the Boolean Union command in Rhino to make the model into one watertight mesh for printing.

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## Tigra

Hi guys,

The thread seems to be a bit old but maybe there are any news on the matter? I am having trouble with casting both FTX green and Green Cast. The cartridge is extremely fragile, that's true and I do had issues with prints breaking off but seems that manually placed thik supports do the trick, at least for the rings.

I used plasticast and formula 1. Formula seems to give an ok quality but quite difficult to remove. I cannot get the plasticast going so far. Still bad surface and ash. Bfrod900 - you've managed to get quite decent surface on one of the pictures, can you tell a bit more the details on how you've managed to do that if it is not too much trouble?

Another question, I've heard form a caster that he vaccums the flasks after the burnout to remove any residual ash, what do you think, will it help?

By the way I have noticed that thin patterns like nets and thin rings come out nearly fine but if there is more of the material it will ruin the cast. I guess it has to do with expansion and curing both.

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## awerby

If there is residual ash, then yes, vacuuming will help by removing some of it. But a resin used for casting needs to burn out completely, leaving no residues. If there is some, then you're either not getting the mold hot enough or using an unsuitable resin. Be careful about doing this, by the way. If you suck up hot particles from a super-heated mold, there's a good chance it can start a fire in your vacuum cleaner, which the forced air will quickly accelerate into a raging inferno. 

If the thin parts of your casting are coming out well but the thick parts are not, it might be due to shrinkage and not the fault of the resin. Make sure the thick parts of your model are connected by a thick sprue to a substantial pour-cup or riser, so the solidifying metal has still-liquid metal to draw from. 

Andrew Werby
Juxtamorph.com

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## bford903

> Hi guys,
> 
> The thread seems to be a bit old but maybe there are any news on the matter? I am having trouble with casting both FTX green and Green Cast. The cartridge is extremely fragile, that's true and I do had issues with prints breaking off but seems that manually placed thik supports do the trick, at least for the rings.
> 
> I used plasticast and formula 1. Formula seems to give an ok quality but quite difficult to remove. I cannot get the plasticast going so far. Still bad surface and ash. Bfrod900 - you've managed to get quite decent surface on one of the pictures, can you tell a bit more the details on how you've managed to do that if it is not too much trouble?
> 
> Another question, I've heard form a caster that he vaccums the flasks after the burnout to remove any residual ash, what do you think, will it help?
> 
> By the way I have noticed that thin patterns like nets and thin rings come out nearly fine but if there is more of the material it will ruin the cast. I guess it has to do with expansion and curing both.


With FTX Cast, you have to cure, and cure, and cure, and then cure some more. It will turn from a light-green shade to white with a hint of pink. Sometimes I would have to run 6-10 cycles in the cure chamber. Larger pieces are hit-or-miss but smaller pieces cast better after extended curing. I think the reason is FTX Green is relatively transparent so the piece cures inside and out, while the FTX Cast is more opaque leaving uncured resin inside the piece. Don't know, but that's my theory.

When you mix the Plasticast, make it as thick as possible. Not too thick where it sets early or won't pour, but as thick as you can make it. This will increase the strength. 

I tried using air duster to blow out the ash residue before casting, but you need to make a separate sprue for the ash residue to escape or it just blows around in there. It helped with the bad surfaces a little, but I was nervous about blowing cold air on a hot mold. Plus, an escape-hole sprue requires extra metal which costs money.

I've gone back to using FTX Green and making rubber molds from the prints.

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## tato887

hello friends my English is not very good but try to explicarne mnejor what you can to see if together we can help.

talk to a person in brooklyn and gave me some instructions to the ftxcastgreen casting material.
proceeded to do the above, so to speak had not an uncertain outcome because I do not possess the proper investment that I could get in my country, but I think that with the right investment you can have optimal results.

I recommended some parts tilt printed on the Geomagic software in order to have more clarity in the pieces.

after printing the piece acquire a liquid called glycerin for sale at any pharmacy.

introducing a glass with liquid glycerine, in section curing, then with a thread holding the part where the tray is placed, and enter the printed piece in the liquid glycerin and cure 3-4 times until it becomes one light violet color.

This process causes the printed piece to keep the color when casted is performed.

I think I had an uncertain outcome because what casts it went well and what I need is to get the right investment.

I have a question with the material have been able to cast ftxgreen somehow ??????

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## bford903

> hello friends my English is not very good but try to explicarne mnejor what you can to see if together we can help.
> 
> talk to a person in brooklyn and gave me some instructions to the ftxcastgreen casting material.
> proceeded to do the above, so to speak had not an uncertain outcome because I do not possess the proper investment that I could get in my country, but I think that with the right investment you can have optimal results.
> 
> I recommended some parts tilt printed on the Geomagic software in order to have more clarity in the pieces.
> 
> after printing the piece acquire a liquid called glycerin for sale at any pharmacy.
> 
> ...


If the investment you need is unavailable where you are located, I would suggest making a mold from the printed piece. FTX Green can withstand temperatures up to 800F (426C) without deforming. This allows you to make a rubber mold using a vulcanizer. The vulcanization process requires temperatures of 300F (148C). 

If you don't have access to a vulcanizer, making a silicone mold requires no heat at all and the result will be the same. Just mix and pour. Then you can inject wax, or any other castable material into the mold for casting. 

This way you get a high quality product while keeping costs down. 

The instructions and materials needed for casting FTX Green are on Page 2 of this thread. Good luck.

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## Tigra

> With FTX Cast, you have to cure, and cure, and cure, and then cure some more. It will turn from a light-green shade to white with a hint of pink. Sometimes I would have to run 6-10 cycles in the cure chamber. Larger pieces are hit-or-miss but smaller pieces cast better after extended curing. I think the reason is FTX Green is relatively transparent so the piece cures inside and out, while the FTX Cast is more opaque leaving uncured resin inside the piece. Don't know, but that's my theory.
> 
> When you mix the Plasticast, make it as thick as possible. Not too thick where it sets early or won't pour, but as thick as you can make it. This will increase the strength. 
> 
> I tried using air duster to blow out the ash residue before casting, but you need to make a separate sprue for the ash residue to escape or it just blows around in there. It helped with the bad surfaces a little, but I was nervous about blowing cold air on a hot mold. Plus, an escape-hole sprue requires extra metal which costs money.
> 
> I've gone back to using FTX Green and making rubber molds from the prints.


A little bit late but thank you for the reply. About the cartridge tearing problem. With Cast cartridges they are indeed of an awfull quality but I used workaround. I end up moving the material to an empty cartridge of Green one which was much sturdier and end up getting normal prints. Also placing the thickest supports do the trick. Do not use thin supports with this material. I always end up with a half printed piece in the cartridge fallen off from the print plate if I used thin ones.

Well the all idea is not to use additional phases like rubber molding. In that case why do I need printer for? I can get the form in wax from designer and just do regular casting than. No point.

The posphate based investment seems to do the trick but it is very difficult to divest. I do it with screwdriver and hammer but.... comeon! should I pay for divesting machine because their recommended investment do not work?

I tried the recommended schedule for Plasticat - faled with the surface quality. I tried to extend the time twice - no results. I am getting rough surface. Seems that the material have some kind of temperature barier after which it starts getting an explosive boilup and that ruins the inner surface of the curing investment.

Also I noted that the lesser water in the Plasticast mix is better. I used 35/100 ratio first and it was better than 38/100 ratio I used the other time.

Now I am a bit into deadend. My friend recommends doing 14 hour burnout scheme but I doubt that it will help.

Any ideas on the chemical composition of the materials? this may help getting the correct temperature ladder which may help avoiding that explosive burnout which supposidly ruins the inner surface.

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## bford903

*Also placing the thickest supports do the trick. Do not use thin supports with this material.* - A lot of the work I do has pretty fine detail and the thick supports left lots of cleanup on the piece. Also, because of the delicacy of the material, I found it was prone to breaking as I removed the thicker supports, especially with smaller pieces. 

*Well the all idea is not to use additional phases like rubber molding. In that case why do I need printer for? I can get the form in wax from designer and just do regular casting than. No point.* - The idea is to provide the highest quality product to my customer with the materials and tools I have at my disposal. That's the point. The end result is most important. I also run a wax mill, a Roland JWX-30 4-axis Wax Milling Machine, and milling machines are limited by where the cutter can reach. 3D printers don't have these limitations, allowing for more complex and detailed designs while cutting down on build time and assembly after casting. In the case of mass manufacturing, you will need a master mold anyway for repeated castings. I still use both the 3D printer and the wax mill depending on the job requirements. Same way I have multiple hammers in my bench. One does not replace the other, they both have their uses depending on what the job requires.

*The posphate based investment seems to do the trick but it is very difficult to divest. I do it with screwdriver and hammer but.... comeon! should I pay for divesting machine because their recommended investment do not work? -* If you don't like working with it, then don't. Platinum casters do it everyday, and I agree it is difficult to remove, which is why I use molds. I didn't want to buy a divesting machine either, so I figured out a workaround using the materials and tools at my disposal to achieve the desired result. Molding allows me to achieve a high quality product, utilizing the complexity 3D printing offers, with the tools already available at the shop. 

*I tried the recommended schedule for Plasticat - faled with the surface quality. I tried to extend the time twice - no results. I am getting rough surface. -* Extended burnouts didn't help for me either. I was limited to a 6-8 hour burnout due to the limitations of the shop I work in. FTX Cast does require extended curing. Thicker pieces usually contained uncured resin inside, which was causing porosity and investment breakdown during burnout. I would extend the curing time of your prints considerably before casting, until the light-green shade of your print is completely gone. It should turn to a pinkish-white color when it's properly cured. 

*Any ideas on the chemical composition of the materials? this may help getting the correct temperature ladder which may help avoiding that explosive burnout which supposidly ruins the inner surface. -* With FTX Green, expansion starts at around 800F (426C). Since FTX Cast is still a thermoplastic, I would imagine expansion will start around the same temperature. As far as the chemical composition, you would have to talk to a chemist on that one. 

Don't get me wrong. I'm not singing the praises of the Projet and its materials, but this is what I had to work with. If money is no object, by all means buy the phosphate-bonded investment, the vacuum mixer, and the divesting machine. It cuts down a potentially 10-14hr burnout down to 2 hours and provides a consistent high quality product. But if you're working within a strict budget, like I was, molding was a happy middle-ground allowing me to utilize the complexity and shortened build times the 3D printer offers, using the tools already available in the shop. You just have to decide what's the best use of your time, effort, and expense.

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## Tigra

*I found it was prone to breaking as I removed the thicker supports -*yes, true. It it is problematic. Now I tend to group those supports as a bunch together and technically use them as sprue base and do not remove them, just break the base layer off and it is ready to be used in the jewelry tree(not sure the english equivalent :Smile: . Frequently it work but requires additional work at the end.

*I also run a wax mill, a Roland JWX-30 4-axis Wax Milling Machine -* I do not have them at my disposal as well as rubber molding staff so I have to make this option work somehow :Smile: 

*Platinum investment - If you don't like working with it, then don't. -* That was a good advice :Smile:  thank you, never thought about that :Smile:  :Smile: . Just joking. I definitely dont as it requires more effort than the regular investment but for now was the only way I got more or less reliable surface. As I do not want to do additional investments into specialised technology for working with this kind of investment I still want to try make the Plasticast work. By the way I tried to dilute this investment a bit also and seems that Formula also works the best thiker rather than diluted. One clear advantage of phosphate based investments is the possibility for rapid burnout.

*It should turn to a pinkish-white color when it's properly cured. -* By the way I tried mixing the green and cast materials, added a bit green in it. It basically behaves as cast in terms of curing but was a bit sturdier. Also you do not have to use up the curing lamp resource, direct sunlight does the same trick. Just leave them under direct light for half a day or a day.

*FTX Green, expansion starts at around 800F (426C) -* thank you for this data. It definitely starts smell plasticky around 300C. The only thing I havent tried is to increase the process of climbing the temperature from 150C to 500C to 3-4 hours hoping that the degrading and oxidising of plastics will happen slowly, fully burn the ash and will ruin less the surface during the burnout. It seems that the rapid burnout ruins the walls inside the mold with regular investments and lives small trash pieces inside. When metal filles in the mold the trash pieces ruin the surface leaving dents in it. For example Sample 1.jpgSample 2.jpgSample 3.jpg

* But if you're working within a strict budget, like I was -* yes, that is true also. The investment should be justified. The thing is I do not have materials and instruments for rubber molding so I have to buy them as well if I will go that way and for the moment I am trying to avoild it. Actually I wrote to their support asking the questions but have no answer so far. I have a feeling that their advirtisement for a "castable" material was a bit too optimistic.

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## bford903

Yeah rapid burnout will not work with Plasticast. Tried it myself and my results were similar to yours. 

You could try silicone molds instead of rubber as a cheaper option. No vulcanizer, just mix and pour. 

Good luck with their support. They were not helpful to me at all. They basically told me, "We make 3D printers, we're not casters." Then they wouldn't return my phone calls or emails. 

I became fed up trying to achieve consistent results with FTX Cast. You're definitely more patient than I was. But you seem to be on the right track. Good luck and feel free to post your results here. 


You'll enjoy this. This is what's happening inside during burnout. This is a 15mm sphere I put in the oven by itself, no flask or investment. The part I'm holding is the sphere and the bubble above is the material from inside. This happened at about 800F. Looks like coal. This is the material left over inside the investment when you pour your metal. I think this may be an inherent problem when trying to burnout any thermoplastic. 
IMAG0262.jpg

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## awerby

800F isn't high enough to completely combust wax, not to mention plastics. You need to get to about 1200F to cast a wax-based mold, and most plastics require 1300 or higher. That's why MgO-based investments intended for platinum casting work better than regular plaster-based investments for casting 3D printed models. 

Andrew Werby
Juxtamorph.com

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## Tigra

Yes, it is not. The working temperature for comustion of this plastic according to Plasticast is 1350F and you have to keep it in the oven for at least a couple of hours. The big question is when exatcly does it start to expand or boil up explosively which actually ruins the inner surface and leaves the end result porous and nonworkable. If we manage to get the exact temperature we may put a good delay on this temperature diapason (for example let it rise from 300C to 600C for 6 hours slowly) and then we may avoid that explosive boliup phase and get cleaner results as the Plasticast claim to withstand the expansion of the material. At least this is my guess for now.

In general I have nothing  so far from the support. I'd say for the moment it is false advertisment and this thing is punishable by law if I am not mistaking.

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## Tigra

*Looks like coal. -*my guess is the material is partially some kind of alcohol, some photopolimer and some minerals added for the stability. And those minerals combust like this coal pieces. Now I am thinking if we rise the temperature really slow alowing the material fully oxidize and combust this may leave small amount of residual ash. my greatest problem for the moment is not the ash, it is the surface quality I am having after the burnout.

*You could try silicone molds instead of rubber as a cheaper option. No vulcanizer, just mix and pour. -* I will still need wax injector correct? And the silicone one may not give the same quality. I do not have any experience with this technique so far.

By the way, about the divesting liquid, how well does it work and is it expensive? I was doing mechanical divesting of Formula and I cannot say that it can win any stars in the favourite activities competition.

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## survivalist

Can anyone recommend a low cost silicone material that is great for making molds out of complex high detail ftx green jewelry prints?


All silicones i have used in the past has been for sculpture where cutting the silicone material would make it rip. Seems like Castaldo liquafast Ice looks like a pretty nice soluction considering its ez two part and transparent for easier cutting, but it is quite expensive.

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## bford903

*By the way, about the divesting liquid, how well does it work and is it expensive? I was doing mechanical divesting of Formula and I cannot say that it can win any stars in the favourite activities competition. -*LOL! I feel the same way. I felt like a paleontologist removing rock from a new fossil specimen. My guess is the rough surface quality may be caused either by residual ash left over in the cavity when pouring the metal, or the cavity walls are cracking and breaking during the expansion of the material. I've consulted a few people who theorize the photopolymers may be interacting chemically with the investment during burnout, causing the rough surface textures, but I'm not sure how to confirm that. 

Here's some info on divesting from Ganoskin:

Removing the castings from the investment can be a challenge. The investment, which is baked at very high temperatures, turns into a glass-like substance that can be difficult to separate from the cast pieces.
Most manufacturers use hydrofluoric acid, which is extremely dangerous and must be handled with utmost caution. Always use rubber gloves, a rubber apron, and a respirator that filters small particles from the air.
A small shop may wish to consider a safer devesting agent for platinum investment as a substitute for hydrofluoric acid. Ask your tool supplier; there are many brand names. You can also mix your own substitute using the following formula (percent- ages are given by weight): 25 percent sodium hydroxide, 25 percent potassium hydroxide, and 50 percent deionized or distilled water. (The sodium hydroxide and the potassium hydroxide should be in pearl or flake form.) Combine all three solutions in a stainless steel container, and heat (do not boil) for 25 to 40 minutes. Be careful mixing, since the three ingredients will naturally heat up when combined.

Here's a link to a safer divesting solution but it's still a bit pricey. It's a hazmat item so shipping will be more expensive as well: http://www.ishor.com/casting/investment/safe-d-vest-investment-remover


I usually soaked it in the divesting solution until the investment started to loosen up, then put it in an ultrasonic. Repeat until all investment is removed. Make sure you have good ventilation in the area you're divesting. 


@survivalist
I've always used Castaldo for my molds. It's pretty durable stuff in my experience. Haven't tried any of the alternatives.

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## linamvr

Hello all

Finally I have been able to cast FTX green without porosity.



The  process is to cast as if you where casting platinum. The secret lies in  the investment and its expansion capacity. To get a good expansion  capacity ( to avoid internal fractures), you need to use Phosphate  bonded investment. 

In countries where you  cant find this in jewelry supply stores, look for this in dental supply  stores because it is the same investment used for dental casting.

I used the fastfire 15 from Whipmix and the process I followed was the following. 
http://whipmix.com/product/fastfire-15/

1.  Prepare the investment as per instructions (per 100 grams, 27 mils of  the binding liquid sold with the investment). I did not add any water.  Be very quick while mixing since it gets hard very very fast. 

REMEMBER TO PREHEAT THE OVEN AT 730 DEGREES CELCIUS

2.Vacuum the investment mix

3.Put  some tape around the top of the flask because while vacuming it rises a  lot. Use liner inside the flask . (liner is sold by Whipmix - and it is  an asbestos paper to control thermal expansion.
Pour the investment mix and vacuum the flask again.

4.It will become very hot while it hardens due to a chemical reaction of the mix

5.Hold still and dont move the flask for 20 minutes

6. Put the flask in the oven (remember you had preheated it!) fo 1 hour and 15 minutes at 730° celcius

7.  Lower temperature to your metals recomended casting temperature (ej.  white gold with palladium at 490° C) and stay at that temperature for 30  minutes

8. Cast (I use centrifuge)

10.  The investment gets very hard , I used a hammer to help me crack it. If  you need, buy the investment remover also sold at dental supply stores.



The results are great, hope you get as good a result as well. I will post pictures soon



Lina

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## survivalist

@bford903 What exact product from castaldo have you been using ? There is many choices from castaldo namely ; *LiquaCast®*
*LiquaCast®Long-Life™*
*LiquaGlass®*
*LiquaFast ICE®*

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## bford903

> @bford903 What exact product from castaldo have you been using ? There is many choices from castaldo namely ; *LiquaCast®*
> *LiquaCast®Long-Life™*
> *LiquaGlass®*
> *LiquaFast ICE®*


I was using LiquaCast. It's a light pink color.

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## tato887

thanks very much for your help linamvr, but i have some questions, i saw some products in whip mix, and one product is call ceramigold and is a phosphated investmens ypou try whit this produc ??

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## B-3

Did you ever build an an external curing chamber?  If so what did you use?

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## STL Summit Co

Hello all,
I've been attempting to print and cast using the projet for about a month now.  As many of you have mentioned, I've found the CAST resin to be pretty unreliable.  I am particularly frustrated by the lack of information from the companies that sell these machines and resins.  They have been almost no help.  Thank goodness for forums like these.  I plan to try the previously mentioned steps which include the phosphate bonded investment but I've never used it before.  Are there any risks of contamination from the gypsum based investment being mixed using the same equipment?  Also, does the FTX green require the same type of extended curing times as the CAST?  Or, is it not an issue because of the strength of the investment?

Thanks in advance,

Tina

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## LinerArt

Hi all,
if this thread is still alive, we're a small jewelry design company in Saint Louis, MO with a Projet 1200 printer. We've been having nothing but trouble with this ... printer practically from day one. The fact that none of these materials are actually truly cast-able (contrary to what the company falsely-advertised) has been the main issue. So the question is, does anyone know or can recommend another 3D printer alternative, that is comparable in price (under $5000) and can produce decent quality prints out of materials that are truly easily cast-able?

Really appreciate your help!

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## awerby

No plastic resin materials cast as easily as wax, which melts and flows out of the mold instead of sticking in there and burning, but some cast better than others. If you need a machine that builds models in real wax, the only one I know of is the Solidscape, but that's outside your budget range. I've had good luck with the B9 Creator, which uses a resin that burns out pretty well. It helps to use Plasticast investment, which can tolerate a little more heat than normal investments, and to introduce a little extra air into the kiln at the last stage of the burnout cycle. You might try that with your Projet models before giving up on it. But if it still doesn't work, I've got an extra V1.1 B9 I can sell for $3k. 

Andrew Werby
www.computersculpture.com

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## LinerArt

Hi Andrew, thank you for your input! We've sent you a message through the messaging option, let me know if you received it. We wanted to discuss the B-9 that you've got.

You can email to: linerart at gmail.com

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