I’ve been printing with Siraya Tech Sculpt for about a year now and I have used a top of it. I’m close to probably 30 liters of Sculpt by printing my injection molds for my fishing lures so I want to share my experiences and the pluses and minuses of using Siraya Tech Sculpt. Let’s go.
Why To Use Siraya Tech Sculpt
So first, let’s talk about why you would want to use Siraya Tech Sculpt and why you wouldn’t want to use Siraya Tech Sculpt. Why you would want to use it is super simple- high deflection temperature. Siraya Tech Sculpt is one of the resins that has the highest heat deflection temperature, at least in consumer level 3D printed resin. Its heat deflection temperature is 260 degrees Celsius which comes out to about 320 degrees Fahrenheit. We’re going to dive into heat deflection temperature in just a second but that is the primary benefit of Sculpt, it handles high temperatures, it prints well and gets really good details but you only really want to use it for high temperature resistance.
So let’s talk about heat deflection temperature really quick. First of all, I’m not an Engineer of any kind and I’m definitely not a materials Engineer so what I’m about to share with you is a combination of what I’ve been able to tell from the test that determines heat deflection temperature as well as my own experiences. So heat deflection temperature is determined using a test where they print a standard size of the material in question. Now, a lot of people look at heat deflection temperature (in this case 160 Celsius) as kind of an absolute number and that’s not really true. If you print a thinner piece of Sculpt, say one millimeter thick, it will not be able to absorb or reach the temperature of 160 Celsius before deforming because it’s a smaller piece of material. Conversely, when I print my molds they’re about 15 millimeters thick on each side and I have been able to inject them with 400 or even slightly over 400 degree Plastisol with no real issues whatsoever. My molds are clamped either with a vise or with bolts pushing them in further, strengthening them against any deformation from heat. 350 degrees is the temperature Plastisol converts to a usable product at and a lot of people look at 320 degrees and think it’s not going to work. It works totally fine even at higher temperatures as mold as your mold is made the way I make mine which again is 15 millimeters thick on each side.
Why Not To Use Siraya Tech Sculpt
Let’s talk about why you don’t want to use Siraya Tech Sculpt. If you don’t need the high heat deflection properties of Sculpt, just don’t use it. As you’ll see coming up, it’s kind of a hassle to work with and you’re much better off using some other resin from Siraya Tech that’s fast and easy, any of the normal printing resins that are much easier to deal with and still gets you similar results to Sculpt in terms of detail. You just don’t want to mess with it if you don’t have to.
Let’s talk about actually printing Sculpt. One of the things that they mention in the documentation (which I’ve linked HERE) is that it want to be above 25 Celsius. However, what you really want to think about is if you print it below that temperature, your exposure time is going to be greater and while you’re printing the resin is actually getting warmer. Say it starts at 23 degrees Celsius and as you’re printing it’s warming up and it go up to 26 degrees Celsius, you’re going to dramatically over expose and your print is going to look pretty bad after it converts to that point. So really, what you want to think about is the stability, you can print it at a lower temperature as long as you keep it lower than 25 degrees Celsius and if you print it warmer you just want to make sure that you start at 25 degrees Celsius or slight above during the printing process because it will just warm up as you’re going. So they don’t mention that the 35C is kind close to the top range so if you’re heating it with something that is going to produce temperatures above that range, you might have other things happen. I like to keep mine right at 25 degrees Celsius when I start so it warms up a few degrees while it’s printing.
Let’s talk about post-processing. My print is done and it’s looking good, now what. This is, again, where Sculpt is a little more difficult to deal with than a lot of other resins. So first off, Sculpt likes to be cleaned in a very high alcohol content environment. I ended up using denatured alcohol and the reason for that is it evaporates relatively quickly compared to Isopropyl alcohol. You can also use acetone which I did use for a while, it evaporates very quickly but it was very irritating to both my eyes and nose even with a mask on. I’d often walk off and leave the container open and I’d come back to my shop and it would just be filled with acetone fumes which isn’t good so I switched to denatured alcohol and it seems to be doing well.
The other thing to note is that Sculpt does not want to be in any of these substances for longer than 30 seconds. It will actually start to break down and you’ll kind of skim across it and it’ll almost peel or flake and that’s when you know you’ve had it in there too long. My process is pretty straightforward, I take it off the printer and I wipe a lot of the excess resin on a paper towel. Sculpt is very thick and it clings to the model a lot so this rubbing takes off quite a large amount of Sculpt before you even get into your first cleaning. I then use a two-part clean, I have a dirty clean where I put it in there, swish it around (remember, you don’t want it in there for more than 30 seconds, it’s typically good after 15 seconds) then rub it off. Then it goes into a clean isopropyl alcohol bath and this is really just to get off any of the little buts it picked up from the dirty bath. You run it through there again really quick, maybe 15-20 seconds, lightly rub it off and let it dry. I usually just dry it off with a paper towel and let the rest evaporate but if you want a faster dry off you can always use a hair dryer or a heat gun to evaporate that liquid a little quicker, just don’t leave the heat on there for longer than 30 seconds or it will cause problems with your model.
Now before curing you want to make sure it is 100 percent dry since it will not cure if there’s any alcohol left on it at all and you’ll get an incomplete cure and sticky model. You can also look at the model and see if there’s any shiny parts on there and that’s also a good indication that you might not have all of the uncured resin off. Again, Sculpt is very thick and it tends to cling and hold onto models a lot. So the last step is curing and I throw it in my cure chamber for 25 minutes which is the recommended time from Siraya Tech and that seems to work just fine. If you’re putting it outside you may want to have it go for a little longer. You don’t want to put it in water to cure it, that’s not going to help Sculpt at all.
After you print one part you’re going to want to print another and Sculpt tends to settle in the vat so what you want to do before even adding more Sculpt to your vat if you’re adding more is to get a plastic scraper and go back and forth lightly across the vat. You’ll see there at the bottom there’s kind of this gray film that tends to accumulate and that’s the resin settling and clumping together and you need to get those up before you print again and it leads to all sorts of problems either from under exposure from the base layer not sticking correctly or just simply not working. So give it a good stir to get all of the polymer off of the bottom and the sides and make sure you shake up your resin bottle that you’re adding since the polymers are really thick and you want them to move around. Once the resin is in, give it another quick swirl just to make sure it’s all integrated and then you’re ready to go. This stirring also exposes the FEP to oxygen which kind of prevents it from sticking excessively and gets you a better release of your mold while you’re printing.
That’s it guys, if you want to see some of the molds I’ve printed with sculpt, you can see them HERE. If you want to see other people’s impressions of Sculpt, I put together a playlist of everybody else’s sculpt videos right HERE.
Take care- Tight lines