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Hi guys,

I really need to try and pin a process for using soluble supports and would appreciate any input from your collective experience.

I have been researching and there is a lot of doom and gloom surrounding the subject online.

I can see that stratasys printers appear to have have a good soluble material, but they are very obnoxiously priced for fdm printers. Does anybody know what polymer their soluble support material is? I presume this is a closely guarded secret so that they can charge the prices they do.

I have seen info about using water soluble pva support for pla. Problems are the cost of the pva, storage of the pva, and difficulty printing the pva, and importantly for me, I would like to be able to vapour smooth the finished parts, which cannot be done successfully with pla.

Then there is HIPS support for abs soluble in d-limonene. Again, not very successful trials according to whats posted online, plus the fact D-limonene is expensive and cannot be re-used, but I am still interested in looking into this further.

I have come across some old posts regarding using pla supports for abs which currently sounds the most interesting to me, but there doesn’t seem to be any recent information on this leading me to believe that this technique may not be that good. The info basically said to dissolve the pla in a sodium hydroxide solution in an ultra sonic cleaner. I certainly want to run some trial on this.

Basically has anyone had any success with soluble supports for a base material which can be vapour smoothed, and can recommend a good material combination, or is this the holy grail which has not yet materialized yet?

I’m not adverse to working with various chemicals, as we already have chemicals at my company and we have relevant PPE / ventilation and waste disposal contracts in place etc.

Like I said, I have already read all the doom and gloom, so please don’t repeat this back at me, would just like to hear if anybody has had any success to hopefully save me a bit of time in the trials before I start going down the wrong path.

Thanks very much guys.

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Hi @MattG!

Fortunately for you, all that doom and gloom you read online regarding soluble supports (HIPS and PVA mainly) is just not true! I have had really great results with both of those soluble materials (more so HIPS than PVA, but PVA is doable). I don’t have any images unfortunately; by the time the print is done, I’m too excited to see the final product than to bother taking pictures.

I have a couple tips, but the bottom-line I have found with both of these materials is to make sure you buy the best quality possible. I buy primarily from Matterhackers and have really good results with their brand of PVA and HIPS, but had an awful time with PVA when I used a trial sample from a couple smaller companies. I suppose the samples probably got wet and lost diameter consistency, but it was a nightmare. I couldn’t get it to work at all, but had completely the opposite experience with a roll from Matterhackers. Just goes to show how much quality of the brand matters.

PVA behaves a lot more like a TPU than PLA or ABS; at room temperature it’s very soft and almost squishy. It is very important to print this slow and at 100% infill for the support (if you use Simplify this value is adjustable, most other programs are 100% by default). I print at speeds similar to what you’d use with Ninjaflex, which the PVA seems really happy with but the print takes forever. You have to decide if the extra print time is worth the increased print quality and lack of support marks. In terms of manufacturer, I’ve heard good things about Aquasolve but have yet to try it and have had really good experience with Matterhackers.

HIPS is a beautiful material to work with and prints much more like a normal thermoplastic than PVA does. The nicest thing about HIPS is that it’s a true plastic, and can be used as a printing material on it’s own, unlike PVA which really only can function as support material. It’s also used in production for plastic cutlery and other food applications, so it’s not a new/experimental plastic and there’s a lot of information about it out there. It works great with ABS for me, and d-limonene is a fairly tame chemical. It can be printed at similar speeds, so it doesn’t slow down the print all that much like PVA does.

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Thanks so much for your response, I guess that makes sense, not all materials are the same which probably is where all the horror stories stem from! Also I’m guessing that variation in brands can cause adhesion issues between the different materials.

So you would recommend matterhackers? I’ll look them up and see if I can source that in the UK.

If possible, could you share a bit of experience with dissolving in D limonine? eg do you dilute it or use it neat, I guess heat / agitation can only help, so I was thinking about putting it in an ultrasonic cleaner.

Also, are you able to re-use the limonene or is it one use and throw away, which could end up being quite expensive by the looks of the price of the stuff.

Thanks again for your quick response.

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What about using ABS as a support for HIPS, dissolve abs in acetone and vapour treat hips parts with D-limonene vapour?

I’m thinking this for cost saving and sounds like hips is actually a good alternative to abs for usability and functionality.

Or is that just silly, I’m just thinking out loud ;0)

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Brand variations don’t seem to be as much of a problem with HIPS as with PVA, which makes sense as well seeing as the air is almost always moist and it definitely loves to suck up moisture. I’m pretty sure Matterhackers just uses MakerGeeks or eSun’s filament and brands it as theirs, so it doesn’t necessarily have to be from them. I’d say any reputable brand is a safe bet, except Makerbot; I’ve heard more complaints than positive reviews about their brand of HIPS so I’d steer away from them.

Technically, you want to use ®-(+)-Limonene to dissolve HIPS, D-Limonene isn’t actually the correct variety of Limonene to use for this. It will work eventually, but the ®-(+)-Limonene variant works much better (my mistake in the earlier post!). It’s a bit harder to find than it’s cousin limonene variant but works very well! I’ve had best results using a 1:1 solution of limonene and isopropyl alcohol; the addition of heat & agitation would definitely expedite the process so an ultrasonic cleaner would work nicely here. I use the bath a couple of times and only change the solution when it’s noticeably cloudy or the supports take a really long time to dissolve; so generally one bath is good for a couple small prints, and a few for larger prints.

For large prints with lots of support, I suggest removing as much of the HIPS support material as you can before putting the part in the limonene bath. Generally, your ABS won’t be affected by the limonene but if left in too long, the colors can start to bleach and the part might curl.

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Thanks very much, I really appreciate you sharing your wisdom and experience. I’m quite excited to give it a try now!

Regards,

Matt

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Its my pleasure! Best of luck!

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Do this in steps.

First, make sure you can dual extrude well, with two colors of the same material. If you are getting a lot of drooling and dragging of one color into another, then when you print with HIPS or PVA, these will be holes when they dissolve. So get dual printing down first, then move on the the next step.

Next step, get good at printing HIPS or PVA standalone. Make sure you get those settings down.

Finally, get your supports settings down, with HIPS or PVA. Unlike normal supports, you want your distance between the support material and the model material to be 0. Something you don’t necessarily want when printing the model and the support in the same material.

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Thanks for the guidance I will take it on board. Currently building a printer for dual extruding. I wanted something with independent dual extruders similar to the bcn3d sigma, but with a blocking mechanism rather than catch trays to help fight ooze. Also wanted direct drive and an enclosed build volume, I couldn’t really find all this on the market so building my own with the end goal of using soluble support for abs parts. It’s good to hear from people with good experience in this area. Thanks again

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Since you are in the UK, have you checked out E3D’s ‘Scaffold’ water soluble support material? They say it is good match for PETG material, which a lot of people are using instead of ABS. I don’t have any personal experience with it yet, although I do have some samples of it that I picked up when E3D came to a show in the US this past spring. One day I will get the courage to try it out! E3D is well regarded for their quality hot-ends.

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I suppose you could physically, but I have a feeling the acetone will warp the HIPS while you dissolve the ABS. I’d also suggest checking the chemical properties of limonene and seeing what the hazards are of aerosolizing it.

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I could plop some hips in acetone to see I guess. Im not to worries about fumes etc, we use a lot worse chemicals so our extraction systems and health and safety kit is pretty good. It wouldn’t be too difficult to build an enclosure hooked up to the extraction system.

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No I haven’t heard of that, but I know e3d have a pretty good rep, and they’re only about 40 miles from me too! I’ll have a look into that, thanks!

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I’m currently building my 3rd printer with these specifications. I’m not sure what your experience is so my best advice is that mechanics/design/construction are the easy part. You will need extensive experience in modifying firmware and your gcode through scripts depending on your design and software choices. I would not recommend a project like this as a first, second, or even third build. Especially if you want anything close to professional quality. If you have already build a few machines and are confident in your abilities then go for it. It works!

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I’ve built one 3d printer, but I have been in engineering in the aerospace industry for 16 years now, so the mechanical engineering side of it comes more naturally to me anyway, the firmware / gcode side of things isn’t too bad, its a lot simpler than 6 axis CNC machines! Glad to hear your had a good experience with this design, that’s inspiring!

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