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  1. #21

    try

    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 ??????

  2. #22
    Technologist bford903's Avatar
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    Quote Originally Posted by tato887 View Post
    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 ??????
    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.

  3. #23
    Quote Originally Posted by bford903 View Post
    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.

  4. #24
    Technologist bford903's Avatar
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    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.


  5. #25
    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. 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

    Platinum investment - If you don't like working with it, then don't. - That was a good advice thank you, never thought about that. 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.

  6. #26
    Technologist bford903's Avatar
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    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

  7. #27
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    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

  8. #28
    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.

  9. #29
    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.



  10. #30
    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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