2010
08.19

My limited knowledge of plastics has bitten me, as I had half expected (hoped) that I could just run the NIP ABS through the Stratasys and have things ‘just work’.  As noted previously, I had used the exact same extruder temperature on the ABS from New Image Plastics as with the Stratasys ABS, but had sagging filaments as a result. Nophead (who is easily one of the most experienced RepRappers out there) guessed that I likely was using too high of a temperature, which made sense. But shouldn’t ABS run just like ABS? Not a chance, as I found out – I had mistakenly assumed that ‘ABS‘ referred to a specific polymer composition, when in fact you can tweak the ratios of the components (Acrylonitrile, Butadiene and Styrene) to achieve certain properties.  Obviously, NIP is using a different formulation than Stratasys is.  Additionally, Erik de Bruijn noted that he had seen different colors of ABS require different temperatures for optimal extrusion.  Stratasys is apparently doing a great deal of work to make all of their P400 ABS colors act identically at 270° C.  Out of interest, here’s the sticker from a Stratasys reel that lists recommended temperatures for various materials:

E20/E20R is an elastomer (and corresponding support material), ICW06/ICW06R is an investment casting wax and support, P400R (high-impact polystyrene) is the support for P400 ABS, and P400SR is a soluble support material.  It’s interesting that the 0.010″ tip suggests a higher temperature (for one material, anyhow) than the 0.012″ or 0.016″ tips, but I suppose this makes sense – you’d need a less viscous fluid when pumping through a smaller orifice in order to maintain the same linear flowrate.

My latest plate of Mendel parts completed with the NIP ABS, but the results were not as good as with the Stratasys ABS, I’m sorry to say.  I had severe warping on the larger parts, though this could be due in part to me dropping the extrusion temperature down by 15° C early on in the build as a result of nophead’s suggestion.  On the plus side, the NIP peels off of the support material just beautifully (perhaps a little too well, as one of the drive-pulley_3off parts became detached from the raft near the end of the build).  I’m wondering if the lower adhesion between the two materials may have also contributed to the warping – keeping the corners held down more securely may be part of the secret of getting more accurate prints.

I also notice a lot of fine feathery filaments with the NIP ABS at the end of an extrusion path.  Whereas the Stratasys ABS acts like a microscale toothpaste, the NIP ABS acts like a microscale silicone caulk.  The NIP ABS also shows its displeasure at the higher temperatures by turning brown after sticking to the nozzle for a while (meanwhile the Stratasys ABS would simply lose a bit of color, but not appear to actually be charring).  So, time for some testing to see if there is a magic temperature at which the NIP ABS acts like the Stratasys ABS.

I adjusted the white balance on this photo to better capture the filament detail – the parts really do not look this grubby, although it’s interesting to note that the highest temperature pass does look a bit browner than the others.  I created a box with the 0.15″ crosshatch fill in Quickslice, and ran it at ever decreasing temperatures on the Stratasys.  At the recommended 270° C for Stratasys ABS, the NIP ABS is practically dripping off of lower layers.  As the extrusion temperature drops, the filaments droop less, but even at 240° C there is still a reasonable amount of droop.  At this point I started having slippage on the drive wheels (I think this was due more to buildup of tiny ABS fragments than due to lowering the temperature), and more importantly, I was entirely out of Stratasys support material.  As such, the next phase will be to play with the HIPS from New Image Plastics and see how it differs from the Stratasys support material.

36 comments so far

Add Your Comment
  1. I am surprised it still droops at 240C. The other thing that will make it droop is if the flow rate is too high. Ideally the filament should be stretched a little. Whether it is depends to some extent on how much is swells when extruded. I.e. if it swells more it gets stretched more to get back to the desired size. That makes it span gaps better, but also cuts corners more.

  2. Another interesting post. This raises a lot of questions about variation of print quality within the reprap community, and the possibility of an artificial performance “ceiling”. It’s entirely possible that everyone is optimising their reprap machines to print the grades of ABS that just happen to be currently on sale to/within the community, when there is possibly a much better grade waiting somewhere in the wings! Either reprap needs to do some fundamental material science before making much more progress, or we just look at what’s done industrially and steal that…

    Stratasys patent US20090295032 is interesting:
    “The build material used to build 3D object 18 is a modified ABS material capable of being extruded from extrusion head 12 with improved response times, thereby improving the accuracy of the deposition process. Examples of suitable modified ABS materials for use with the present invention include ABS materials modified with additional monomers, oligomers, and/or polymers, such as acrylate-based materials. Examples of suitable commercially available modified ABS materials include methylmethacrylate-modified ABS/poly(styrene-acrylonitrile) blends under the trade designation “CYCOLAC” ABS MG94-NA1000 from General Electrics Co., Pittsfield, Mass.”

    I’d recommend reading the rest of the patent. It talks about optimum extrusion temperatures, degradation of the ABS at high temperatures, and compares the “modified” ABS with standard ABS. The summary is that standard ABS exhibits non-Newtonian flow which limits the response time of the print head. It requires higher pressure to get the ABS to flow initially then, once flowing, pressure is reduced. The modified ABS, apparently, performs better in this respect. There’s no mention of the silicone-vs-toothpaste characteristic, but it’s quite possible that it also varies between modified and standard ABS.

    NIP will, apparently, extrude customer-supplied polymers, so I reckon the best bet would be to buy some of the Cycolac MG94 from these guys: http://catalog.ides.com/datasheet.aspx?I=28365&E=57277, have it delivered to NIP, get it extruded, and see if it behaves the same as the Stratasys material

  3. Nophead – I played a little more with the ABS today and brought it down to as low as 230° C. 235° C seems to be about the best compromise temperature as far as trying to get straight filaments in the crosshatch infill. Good insight regarding post-extrusion swell – I’ll have to see if I can mic some NIP and Stratasys filaments to see how they compare.

    Jeff – I wholeheartedly agree that perhaps reprap should try to find a particular grade of ABS to work with as a baseline, or at least acknowledge the limitations of ‘generic’ ABS. The Stratasys ABS has me downright spoiled, and I’m getting more and more aggravated with the NIP ABS (not a slight against NIP in any way – they provided exactly what was asked for, and I’ll definitely be seeing what other formulations they can do). I’m quite simply amazed at what nophead and the others have been able to do with such an unruly, temperamental material that warps and lifts corners with no provocation – the annoyance is not something I’d want to subject reprap newbies to, as the material looks to have a major impact on resulting part quality. The more I struggle, the better a deal the Stratasys material prices look.

    I just started reading through the patent application you found, and it looks to be an excellent resource. I did do some digging through ides.com today looking for ABS resin suppliers, and tried matching up material specs of the Stratasys P400 ABS with various offerings. The 20090295032 patent application notes Dow AG700 ABS as the comparative material, and AG700 looks to be fairly similar in properties to the Stratasys P400 ABS. My own searching led to me to believe that Dow was the supplier of ABS resin to Stratasys (specifically an ‘F 2000′ ABS resin that I’ve been able to find no further information on), so this is certainly supporting evidence. Additionally, the AG700 ABS is described as ‘lowest gloss’ of the Magnum ABS resins, which definitely matches the ‘lobster red’ Stratasys P400 ABS I had been using – the NIP ABS has been much shinier in appearance.

    Beyond the AG700 ABS, the MG94-NA1000 ABS sounds very interesting, and I’ll certainly have to look into getting some (as well as the AG700, naturally). Nophead, do you think existing reprap extruders would be able to get up to the temperatures that the MG94-NA1000 ABS appears to like?

  4. The patent seems to be saying “Look how good the modified mg94 is compared to the standard ag700″, so are you sure it’s not what Stratasys are using? If I were you I’d aim straight for the mg94.

  5. I’d actually like to start with the AG700 first, as I want a ‘drop-in’ replacement for the P400 ABS my Stratasys machine uses, so I can be back to making usable parts. The old software that drives my FDM 1600 has no information on these much newer materials (which were never supported for the 1600 anyhow), so I’d have to do a bunch of hacking and experimentation to modify the definition files to run MG94 happily (this would have been my next step with the generic ABS had I not decided to look at alternate materials).

    Don’t get me wrong, I really want to try the MG94 as well, but myself and other old Stratasys owners would like a cheap P400 clone as a first step and baseline material. However, we may be limited by minimum order quantities in the end – I don’t know if Dow or SABIC would be willing to sell resin in anything less than a 2000 lb. load. I called Donna at NIP this morning and talked to her about the ABS – she said that the material Jim gets is just a generic ABS grade and works well for plastic welding, but if we have material specs and/or MSDS sheets for alternate materials, they can see about acquiring it. I emailed her the sheets that I was able to dig up on the AG700 and MG94, so hopefully she and Jim can contact their suppliers and see what our chances are of getting our hands on either material.

  6. Jeff, I did some more digging to try and see if MG94 has actually been used by Stratasys yet (or if the patent application merely hinted at an upcoming material) and it looks like MG94 is a dead ringer for the Stratasys ABS-M30 material. I found other methyl methacrylate modified ABS (MABS) resins as well, such as BASF’s ‘Terlux’ materials.

    I was rather amazed to read in Integrated product and process development: methods, tools, and technologies that “[Stratasys] announced the addition of MABS (methyl methacrylate ABS) to the family of modeling materials available for use with the FDM 1600 in November 1995.” My immediate reaction was “whaaa????” Apparently they are referring to P500 ABS (which Stratasys referred to as ‘Medical ABS’ as it could be sterilized with gamma radiation), which they now refer to as ABSi. Quickslice 6.4 doesn’t have an option for P500 on the FDM 1600, but it does show up for the FDM 1650. I’ll have to dig through the definition files and see how different P500 and P400 tables are. My bigger question at this point is: how does ABSi differ from ABS-M30?

  7. I see, I hadn’t realised that mg94 was such a new development for stratasys. I suppose it must be, given the patent was issued in 2009. I’ll shut up and let you experiment!

  8. Jeff, I hope you do not shut up! Your information led me to investigate further, and reconsider being rather conservative in looking at new materials – hey, I’ve already run generic ABS through my machine, so what could MG94 hurt? :-)

  9. … and I posted that before reading your last comment. The plot thickens! I suppose it’s possible that ABSi and m30 are the same.

  10. Precisely what I’m wondering, so we’ll have to see how the two spec sheets and MSDS sheets compare… This certainly gets interesting!

  11. You’re really digging into this. I don’t have much to add but this: If you could modify the toolpath and feedrates this would allow you to have more control and still work with various polymers. Since you’ve found it to be an off-the-shelf motion control system with an insuccesfully obfusicated protocol, you could write a postprocessor for
    Keep in mind that a polymer made of 3 monomers will show different properties based on the ratios of the monomers that were linked to form the polymer.

  12. You’re really digging into this. I don’t have much to add but this: If you could modify the toolpath and feedrates this would allow you to have more control and still work with various polymers. Since you’ve found it to be an off-the-shelf motion control system with an insuccesfully obfusicated protocol, you could write a postprocessor for one of the several toolpath generators that are there (Skeinforge, the RepRap Java host, RepSnapper).

    One more thing: Keep in mind that a polymer made of 3 monomers will show different properties based on the ratios of the monomers that were linked to form the polymer.

  13. Hello, I am from a Brazilian company called Cemar.
    We have here a Stratasys Prodigy Plus machine and researching about reloading the stratasys cartridges I ended up here!
    I did not really tested anything until now but I will do soon, we are spending a lot with the originals, but as a seller of prototypes we will use a similar material just in case that present real good results.
    If I discover something for here I will let you know, and I will be here to follow your great work.

    Sincerely,
    Luis

  14. After a phone call to Styron, it appears that the AG700 is a dead end. Not because it wasn’t the right resin (it probably was, at least at the time that the patent application was being written), but because it has apparently been discontinued. Not only that, but Dow/Styron/whoever-actually-makes-the-stuff only sells to the automotive industry. At least MG94 still looks to be a current product, and I have an inquiry in to SABIC for the MSDS sheet.

    In comparing the ABSi and ABS-M30 sheets, they do appear to be different products. In looking around at ABS resins from various suppliers, I’m wondering exactly what material properties are desired for FDM. I can’t imagine that Stratasys blindy started running ABS samples through their machines, looking for formulations that didn’t warp or lift corners. Melt flow and deflection temperature would seem like important properties, but I’m curious to know if the ‘low impact’ noted on the AG700 sheet is important.

    Erik – I’ve thought about seeing if I could come up with a postprocessor for Skeinforge, but I have no idea how complex that would be – my programming skills are rather limited.

    Luis – Please let me know if you discover any alternate materials that work well!

  15. you’re dead right, it would be very helpful to know what material properties are relevant in fdm. Perhaps industrial abs extrusion will shed some light on it. Lots of objects are manufactured by abs extrusion, eg. guttering, and abs must be optimised for dimensional stability of extruded profiles. Of course there are more problems in fdm, like layer adhesion, but it might be a start.

    Have you seen this page? http://www.sabic-ip.com/gepapp/Plastics/servlet/ProductsAndServices/Product/series?sltPolymer=ABS&search=Search#searchresults It lists a methacrylate modified abs for “scratch resistance and depth of colour”, mg8000sr. Perhaps it would be a suitable alternative to ag700.

    • I think ‘high flow’ ABS may be what we need for RepRap/Stratasys – both the AG700 and MG94 appear to be ‘high flow’, and such ABS materials appear to be good for molding fine detail. Hmmmm, fine detail… That sounds exactly like what we’re trying to accomplish, given nozzle orifices of 0.5mm and less! Not only that, but ‘high flow’ ABS may really cut down on the extruder difficulties that people have had, not to mention increasing the speed at which material can be laid down. The next question would be – does ‘high flow’ ABS still exhibit the warping and corner lifting seen with standard ABS grades?

      Also of interest is the PP3DP printer being talked about in the RepRap forums. The PP3DP website says that you can use Stratasys ABS on the machine, so I asked in the forum for clarification on the filament diameter. They said the plastic is 1.73mm, which is indeed essentially Stratasys diameter. However, I recall seeing somewhere that they mentioned you can get greater part quality by using Stratasys filament, so perhaps they’re still struggling with ideal filament formulation as well. They do say that plastic distribution in the US and Europe will be forthcoming, so hopefully a ready supply won’t be too far off.

  16. SABIC responded, and I just got a copy of the MG94 MSDS sheet. The -NA1000 suffix turns out to be nothing more than the color number, in this case ‘NA’tural. The sheet looks pretty close to the ABS-M30 MSDS sheet, but not an exact match. Still, it’s most likely ‘close enough’, so I’ll see what sort of order quantities they deal with.

  17. Have Blue if you need to increase your quantity, we could make a combined order.
    Let me know the price and term, them we arrange the details how we can do it, if its needed.

  18. I still don’t know pricing yet – I signed up for a customer account, which should hopefully be ready to use in a few days. It appears that all the pricing is online and automated, so hopefully I can check out the cost of other resins as well.

  19. Hi All,

    It see this thread has been dead for a few months now. That said, I have a Stratasys Dimension Elite. I have played with some aftermarket materials that are sold by a third party company. I found that this material does not work nearly as well as the Stratasys materials. I’m not exactly sure what magic Stratasy has, but their materials build VERY good parts. Yes it’s expensive, but worth it to me. I would love to buy cheaper materials, but not at the expense of being able to build quality parts.

    I do however have some insight for you. The materials available for my machine are P400 and P430. The P430 is referred to as ABS-Plus. This material is noticeably stronger than the P400.

    Another note. I have noticed that the third party materials are significantly shinier that the Stratasys materials. I would be willing to bet that they are using the materials extruded by NIP.

    The dimension Elite also uses water soluble support material. This makes removing supports very simple. Not sure what you have found about those materials, but probably worth looking at. That said, it’s also very expensive.

    The newer Stratasys machines use cartridges with chips in them. This makes refilling impossible unless you can figure out how to reset the chip on them. Anyone have any ideas about how to do that?

    Anyhow, nice thread, I plan to keep my eye on it and am happy to help you with any research.

    Here is the MSD sheet for the P430 (ABS Plus)
    https://confluence.rave.ac.uk/confluence/download/attachments/46596355/MSDS+EU+P430+ABS+Plus+08.pdf

    Here are the material specifications for P430
    http://www.solidimage3d.com/images/Docs/ABS-Plus-Properties.pdf

    Kindest Regards,
    ANthONY MOUSe

    • Hi Anthony!

      I’m pretty sure my FDM 1600 can handle the P430 as well, but my software (Quickslice 6.4, circa late 1999) has no knowledge of it. I believe support for the material finally came with Insight v3.x in 2002 or so. I’ve been trying to find a copy of Insight v6 or earlier to try out, but haven’t found any yet, and I’m not about to pay $2000 to Stratasys for software support that would expire in just over a month anyhow.

      Would you mind revealing the third party supplier(s) you tried? Very interesting that it was also glossy material – perhaps the ‘low gloss’ is indeed the magic property needed for FDM.

      As far as soluble supports, there are a lot of potential materials. PLA looks quite promising (and is a favorite of the RepRap crowd), and Johnny Russell (Ultimachine.com) was working with NIP to try some out. Johnny was also quite excited about trying out the 3801X resin from NatureWorks LLC (http://www.natureworksllc.com/news-and-events/press-releases/2010/01-14-10-high-heat-impact-grade.aspx), but I don’t know if he’s gotten to play with it yet. This post certainly shows promise for PLA as a soluble support: http://ifeelbeta.de/index.php/support/quest-for-support-2

      I’ve had a number of people ask me about refilling/resetting Stratasys cartridges, but as my machine predates such limitations (they don’t make ‘em like they used to!), I have no input on the matter. I’d love to hack on it if I had access to such a machine, though – sniff the line with a digital oscilloscope, and determining the communication should be pretty easy. Jim @ NIP tells me that one of his customers has indeed figured out how to hack cartridges, but he wouldn’t elaborate.

  20. I’m looking for P430 substitute. Any news on acquiring some of the MG94?

    And btw, the stratasys cartridges just use a serial EEPROM chip soldered to a small PCB. Nothing special, and not that hard to reset to “0″.

    • No news yet on getting some MG94 – I’d really like to (New Image would certainly be able to extrude the material), but the cost is quite a bit to risk on the endeavor! Rick @ MakerGear.com has put out the word for an experimental filament club, so perhaps we may see something come out of that.

      Interesting that the Stratasys carts just use a serial EEPROM – super simple to reprogram! I wonder if you could just tie the R/W line high/low to write-protect the cartridge so that it always indicates ‘full’?

  21. Hi Anthony Mouse,

    I just wanted to know whether you would be able to provide some kind of contact to your third party materials provider. Was interested in ordering some material as well.

    Kind Regards,

    Richard.

  22. Hi,
    I have played with the EEprom a bit. but aint a good enugh hacker.
    On my casettes the EEprom is a one-wire. but i haven’t been able to reset it. Anyone out there that can enlighten me on how to reset them?
    I’m interested in using the whole casette and are tired of looking at half full casettes when the eeprom says it’s empty.

  23. Hans, Are you saying you have cartridges that still have material in them but read as 0%?

  24. Anyone interested in 3rd party material check out http://www.bolsonmaterials.com I have a spool of there ABS Max and is working out well, it is cheaper @ 165.00 per (56 Cu inch) spool & comes with a new eeprom chip and price includes shipping.

    Thanks Michael for the link to these guys on on your blog!

  25. Anyone interested in 3rd party materials for Stratasys machines check out http://www.bolsonmaterials.com I have a SST 1200. I have a spool of there ABS Max and is working out well, it is cheaper @ 165.00 per (56 Cu inch) spool & comes with a new eeprom chip and price includes shipping.

    They are also working on a support material that is a water ONLY dissolve!! No Sodium Hydroxide needed! Due to be available soon as I am told.

    Thanks Michael for the link to these guys on on your blog!

  26. Hello,

    I am finishing my first cartridge of an Dimension Elite. As soon as I empty It I will try to read it with an arduino board and compare with an new one.

    • You probably won’t be able to learn much, as all the data is obfuscated/encrypted. You’ll learn more by reading a brand new 100% full EEPROM and continuing to read it as it gets used – I’ll be posting more about this soon.

  27. Resettting the chips is pretty straight forward. I didn’t hack the exact formula but I can read a 100% cassette and write the data to an empty one which becomes 100% again. Nothing else is really needed.

    • My understanding is that the EEPROM’s serial number is part of the encryption – are you saying that you’re been able to take the .hex of a 100% full cartridge, write it to a different EEPROM, and have it work in the machine?

  28. You have to copy a full cartridge eeprom then when the eeprom/cartridge is empty rewrite it with the same info as when it was full.
    Thats what we do. seems to work fine, its just a matter of saving and numbering the chips.

    But now i am having trouble with my machine reading any cartriges and when it does read after rebooting it comes up with ” load failed” but doesnt try to load at all.

    any body have any clues

    • Hm… Sounds like they are tracking the serial numbers internally on the main board. If you put it on another elite, does it have the same problem? On the serial number, maybe try looking at 2 different cartridge eeproms in a hex editor and see if you can find its unique serial number(s). I doubt they are using an algorithm based serial number, but I guess anything is possible.

  29. Hi Jhon I am trying to implement the FDM in a Replicator using a elastomer (not rigid) but is very difficult, so I want to ask how the extruder in the FDM1600 works? In a past work was possible to prototype with a elastomer in this system. I appreciate any help. Thanks

    • I’m not John, but the extruder works very much like a Replicator ((but the heating chamber is much longer with a 90 degree bend in the middle). As such, the FDM likes to feed materials with a much higher melt flow rate.

      Which elastomer are you trying to use? I assume that the filament is kinking and jumping out between the feed wheels and the entrance to the heating tube?