With the support nozzle on the Stratasys still acting up (it likes to stick in the ‘down’ position once the head gets up to temperature), I thought I’d try running without support material for a time so I can at least be back to making parts. While I could technically deposit ABS right onto the […]
With the support nozzle on the Stratasys still acting up (it likes to stick in the ‘down’ position once the head gets up to temperature), I thought I’d try running without support material for a time so I can at least be back to making parts. While I could technically deposit ABS right onto the foam base (as I did with one of my very early prints when I first struggled with feeding support filament), this doesn’t make for nice part bottoms, as the ABS fuses vigorously to the glass foam, embedding the foam into the base of the part. Starts making a mess of the foam itself, too. So, I needed to make a regular build platform just like all modern FDM machines use, RepRap included (Stratasys stopped using foam bases years ago and now uses plastic build platforms instead – I should really find out what polymer they’re now using).
I decided to make a modular platform that I could swap into one of the carriers in place of a piece of foam. A piece of 10.125″x10.125″x0.5″ polycarbonate sheet serves as the ‘base’, into which I drilled holes to accept the pins that normally secure the foam. I drilled and tapped the 4 corners of the polycarbonate for 10-32 screws, and then drilled and counterbored matching holes in a 12″x12″ plate of Garolite from McMaster-Carr. Using plastic tubing as standoffs, 4 button head screws then secured the Garolite plate to the polycarbonate base plate. I wanted a good solid platform, as I knew that the Garolite itself would probably be a poor surface to print onto, and my intent was to clamp other surfaces to the plate with binder clips just as nophead does with his heated build platform.
After trying to level the platform as best I could by tightening down the screws for adjustment (using a feeler gauge between the platform and ABS nozzle), I found that the Garolite is bowed downward slightly in the center. Hopefully this shouldn’t cause any major issues, though – I haven’t measured the amount, but I’m sure it’s less than 10 thou, which is the default layer thickness. This does raise a commonly overlooked use of support material, which is that the support raft helps to ensure that the bottom of the part is flat. Without a support layer, you’re at the mercy of the platform flatness itself. When a raft can be laid down, the first few raft layers can droop or smear to conform to the platform, as the flatness improves with each subsequent layer. Of course, this flatness can be destroyed by part warping, but that’s a separate issue.
With the platform reasonably level, I thought I’d heat up the machine and see if the generic ABS would adhere to it in some manner. I used an alcohol wipe to clean off the platform, knowing that my fingerprints and other gunk would make adhesion much harder. I let the chamber get up to around 55° C before I got too anxious and started extruding (I don’t think the extra 15° C to hit normal temperature would have done much). The generic ABS appeared to have zero affinity for the surface of the Garolite when dropped from perhaps 2mm above, so I brought the nozzle down far enough that it would extrude right onto the surface. With the filament feeding through the nozzle at a 20% feedrate, I jogged the head around. The ABS actually appeared to stick to the surface, but when I opened the door to see how much adhesion there was, I found that there was hardly any. Note that I’m using the Garolite surface as it came – I wonder if sanding/blasting/grinding the gloss layer would improve adhesion any.
For the next test, I placed a silicone sheet (McMaster-Carr part number 8632K62) on the platform to see if that would have any adhesion. None at all, it turns out – the ABS practically bounces off the sheet (which made a lot of sense in hindsight, as silicone sprays are commonly used for release agents). A pity, as the high heat resistance and flexibility would have made for a great surface.
Finally, I thought I’d try what has become quite popular among RepRap users and even UP! printer users – masking tape (specifically blue 3M painter’s tape). I thought this was an entirely ridiculous idea when I first read about it some time ago, but so many people were using it that it wasn’t likely to be a running joke. I applied a few strips of tape to the platform, let the chamber heat up once more, and gave a small Mendel part a shot. I was amazed at the results – the ABS sticks to the tape beautifully, yet separates cleanly once cooled. I still had significant corner lifting, however.
With a decent platform, I thought I’d try my luck once more with running a plate of parts over the Thanksgiving break. I dialed the extruder temperature down to 245° C and let the machine hammer away. I stuck around for a layer and a half, and things were looking okay, so I figured I’d check back in 50 hours when the print should be done. Unfortunately, the print started failing at some point within the next 24 hours, as a coworker who had stopped in at the office noticed that the machine “appeared to be dispensing low-grade dental floss” rather than doing anything productive. Sure enough, I had another chamber full of ABS vomit. The post-mortem points towards massive warping and corner lifting as a likely culprit – one of the parts looked like the hot nozzle had rammed into a lifted side, halting further movement of the head (and causing lost steps as a result). There were also various small tears in the blue tape, so obviously a struggle had ensued.
During all of this, I also thought I’d check to see what sort of die swell I’m getting with the NIP ABS versus the Stratasys ABS. Quite surprisingly, the NIP ABS only swells to 0.013″ (out of a 0.012″ nozzle), while the Stratasys ABS swells up to a whopping 0.017″. The significance of this finally dawned on me a week later – no wonder I was seeing drooping filaments on crosshatch infill, and a ‘bunched up’ looking filament on the first layer. The same volume applied to a smaller diameter filament means that the filament will have to have a longer length! It wasn’t a matter of too much temperature after all (though the generic ABS remains much more finicky than the OEM ABS).
The only way to make the generic ABS work in any tolerable manner will be to modify parameters in Quickslice to account for the significantly reduced die swell when compared to the OEM ABS. However, since properties of the OEM material are very tightly controlled, there is no way in the software to adjust such settings – the only thing that can be modified is the ‘road width’, which may not help me much. Tinkering with the definition file may be the ultimate method of customization. Unfortunately, the file’s format (though sprinkled with some comments) isn’t documented anywhere that I’ve found. This definition file is for a specific machine (FDM 1600), running a specific material (P400 ABS), with a specific nozzle (T12, which has a 0.012″ orifice), at a specific slice height (0.010″). In all, Quickslice 6.4 has has 24 different definition files just for the FDM 1600:
- ICW6 material (an investment casting wax) with a T16 nozzle at slice heights of 0.007″, 0.010″ and 0.014″
- ICW6 material with a T25 nozzle at slice heights of 0.010″ and 0.014″
- ICW6R support material (for the ICW6 build material) with a T16 nozzle at slice heights of 0.007″, 0.010″ and 0.014″
- ICW6R support material with a T25 nozzle at slice heights of 0.010″ and 0.014″
- P301 material (a Nylon formulation) with a T12 nozzle at a slice height of 0.010″
- P301 material with a T25 nozzle at slice heights of 0.010″ and 0.014″
- P301R support material (for the P301 build material) with a T12 nozzle at a slice height of 0.010″
- P301R support material with a T25 nozzle at slice heights of 0.010″ and 0.014″
- P400 material (ABS) with a T12 nozzle at slice heights of 0.007″ and 0.010″
- P400 material with a T25 nozzle at slice heights of 0.010″ and 0.014″
- P400R support material (for the P400 build material) with a T12 nozzle at slice heights of 0.007″ and 0.010″
- P400R support material with a T25 nozzle at slice heights of 0.010″ and 0.014″
The largest portion of the definition file is the flow curves, which is a table comprising a list of entries as follows:
# PDMM START ————————————————————–#
#—— CURVES ————————————————————#
# Flow D Pre Pre Start Start Shut Roll
# Area O Delay Flow Flow Dis. Off Back Speed
# xxxx xxx .xxx xxx xxx xxx xxx xxx xxxxx
PDMM
30 2 .026 79 7 60 41 143 800
31 4 .028 79 9 60 42 143 800
32 6 .030 79 9 60 43 145 800
33 8 .032 79 9 60 44 145 800
34 10 .034 79 11 60 45 147 800
35 12 .036 79 11 60 46 147 800
36 14 .038 79 11 60 47 149 800
37 16 .040 79 11 60 48 149 800
38 18 .042 79 11 60 49 149 800
40 20 .044 79 11 60 50 149 800
41 22 .046 79 13 60 51 149 800
42 24 .048 79 13 60 51 149 800
44 26 .050 79 13 60 51 151 800
45 28 .052 79 13 60 52 151 800
46 30 .054 79 13 60 52 151 800
48 32 .056 79 15 60 52 153 800
49 34 .058 79 15 60 53 153 800
51 36 .060 79 15 60 53 155 800
53 38 .062 79 15 60 53 155 800
54 40 .064 79 15 60 54 155 800
56 42 .066 79 15 60 54 157 800
58 44 .068 79 15 60 54 157 800
60 46 .070 79 15 60 55 157 800
62 48 .072 79 17 60 55 159 800
64 50 .072 79 17 60 56 159 800
66 52 .073 79 17 60 57 159 800
68 54 .074 79 17 60 57 159 800
70 56 .075 79 17 60 58 161 800
72 58 .076 79 17 60 58 161 800
74 60 .077 79 17 60 58 161 800
77 62 .078 79 17 60 59 161 800
79 64 .079 79 17 60 59 163 800
82 66 .080 79 17 60 60 163 800
85 68 .081 79 17 60 60 163 800
87 70 .082 79 17 60 60 163 800
90 72 .083 79 17 60 61 163 800
93 74 .084 79 17 60 61 165 800
96 76 .086 79 17 60 62 165 800
99 78 .087 79 17 60 62 165 800
102 80 .088 79 17 60 62 165 800
106 82 .089 79 19 60 63 165 800
109 84 .091 79 19 60 63 167 800
113 86 .092 79 19 60 64 167 800
116 88 .093 79 19 60 64 167 800
120 90 .094 79 19 60 64 167 800
124 92 .096 79 19 60 64 169 800
128 94 .097 79 19 60 64 169 800
132 96 .098 79 19 60 64 169 800
136 98 .100 79 21 60 65 169 800
141 100 .101 79 21 60 65 171 800
146 102 .102 79 21 60 66 171 800
150 104 .104 79 21 60 67 171 800
155 106 .106 79 21 60 67 171 800
160 108 .107 79 21 60 67 171 800
166 110 .109 79 23 60 68 173 800
171 112 .111 79 23 60 68 173 800
177 114 .112 79 23 60 69 173 800
182 116 .114 79 23 60 69 175 800
188 118 .115 79 25 60 70 175 800
195 120 .117 79 25 60 70 175 800
201 122 .118 79 25 60 70 175 800
208 124 .120 79 25 60 71 175 800
214 126 .122 79 27 60 71 177 800
221 128 .124 79 27 60 72 177 800
229 130 .125 79 27 60 72 177 800
236 132 .127 79 29 60 73 179 800
244 134 .129 79 29 60 73 179 800
252 136 .130 79 29 60 74 179 800
260 138 .132 79 29 60 74 179 800
269 140 .134 79 31 60 75 179 800
277 142 .136 79 31 60 75 181 800
287 144 .138 79 31 60 76 181 800
296 146 .140 79 33 60 77 181 800
306 148 .142 79 33 60 78 181 800
316 150 .144 79 33 60 78 183 800
326 152 .146 79 35 60 79 183 800
337 154 .148 79 35 60 80 183 800
348 156 .150 79 35 60 81 185 800
359 158 .152 79 35 60 81 185 800
371 160 .154 79 37 60 82 185 800
383 162 .156 79 37 60 83 185 800
396 164 .158 79 39 60 84 187 800
409 166 .160 79 39 60 85 187 800
422 168 .162 79 41 60 86 187 800
436 170 .165 79 41 60 87 189 800
450 172 .167 79 41 60 88 189 800
465 174 .169 79 43 60 89 189 800
481 176 .171 79 43 60 90 189 800
496 178 .174 79 45 60 92 191 800
513 180 .176 79 45 60 93 191 800
530 182 .178 79 47 60 94 191 800
547 184 .181 79 47 60 96 193 800
565 186 .184 79 47 60 96 193 800
584 188 .187 79 49 60 97 193 800
603 190 .190 79 49 60 97 195 800
623 192 .192 79 49 60 98 195 800
643 194 .194 79 51 60 98 195 800
664 196 .196 79 51 60 99 197 800
686 198 .199 79 51 60 99 197 800
709 200 .201 79 53 60 100 197 800
732 202 .203 79 53 60 100 199 800
756 204 .205 79 55 60 102 199 800
781 206 .207 79 57 60 104 199 800
807 208 .210 79 59 60 105 201 800
833 210 .213 79 61 60 107 201 800
861 212 .216 79 61 60 108 201 800
889 214 .219 79 63 60 109 201 800
918 216 .222 79 63 60 110 203 800
949 218 .225 79 65 60 111 203 800
980 220 .228 79 67 60 112 205 800
1012 222 .231 79 67 60 113 205 800
1046 224 .234 79 69 60 114 205 800
1080 226 .237 79 69 60 115 207 800
1116 228 .240 79 71 60 116 207 800
1153 230 .242 79 71 60 117 207 800
1191 232 .245 79 73 60 119 209 800
1230 234 .248 79 75 60 120 209 800
1270 236 .251 79 75 60 121 209 800
1312 238 .254 79 75 60 122 211 800
1356 240 .257 79 77 60 123 211 800
1400 242 .260 79 77 60 124 211 800
1446 244 .263 79 79 60 125 213 800
1494 246 .266 79 79 60 126 213 800
1543 248 .269 79 81 60 127 213 800
1594 250 .272 79 81 60 129 215 800
1647 252 .275 79 83 60 130 215 800
1701 254 .278 79 83 60 131 215 800
END PDMM# PDMM END —————————————————————-#
After poking at the definition file with a text editor for a very long while, I realized two things:
- I have spent waaay too much time on researching Stratasys machines, styrenic polymers, and all points of intersection.
- The second column of the flow curves chart is comprised entirely of binary values from 2 to 254.
It seemed a reasonable guess that ‘DO’ means ‘digital output’, and looking through generated .SML files, I saw various PD and MM commands (hence the ‘PDMM’ block of data). The significance of the table only having even values from 2-254 hit me when I saw that bit 0 of the Asymtek’s 8-bit digital output is toggled when switching between the model and support nozzles – bits 1-7 must then be dedicated to controlling the motor speed. This made even more sense when I consulted the Asymtek ACL programming reference and found that PD allows for a Pre-Delay between the digital outputs being set and the start of motion (allowing the filament to start extruding before the head starts moving) and MM allows for the digital outputs to be changed while the system is in the Middle of a Move (so that the feed rollers can be turned off just before the head comes to the end of extruding a path, allowing the ‘post-flow’ to extrude the tail end of the plastic).
The best way to see if modifying the definition file would have an effect was to try generating a test .SML file. I created a .STL file consisting of a block measuring 0.25″x0.25″x0.1″ and generated a test SML file with the default settings and no supports. Here’s a snippet from the file, where the machine lays down the outline for the first layer (note the MA lines – these are Move Absolute commands to X,Y locations, and you’ll see that the moves do indeed make a square).
# Z = 0.0090 S = 0.00900 T = 00:00:00 ### BEGIN FIRST SLICE ###
MA342,342;
XD209;VS100,1;#FC IDX1
MZ-52;
# obj:0 set:Part type:Perim matl:main width:0.0200 Z:0.0090 S:0.0090 (skipfill)
SR800;
PD.115,79;MM;MM0,25;MM60,118;MM-70,175;
AS1;VM4;BC;
MA342,342;
MA111,342;
MA111,111;
MA342,111;
MA342,342;
EC;VM3;MA241,342;# Exit
I knew that the SR800 was a speed setting (Step Rate) – the last column in the flow curve table. Hmmm, I wonder if any of those values in the next line match up with a line of table values…
188 118 .115 79 25 60 70 175 800
Yep, that line looks like a dead ringer. What happens if we change the 800 speed on that line to 801 in the machine definition and generate a new .SML file?
# Z = 0.0090 S = 0.00900 T = 00:00:00 ### BEGIN FIRST SLICE ###
MA342,342;
XD209;VS100,1;#FC IDX1
MZ-52;
# obj:0 set:Part type:Perim matl:main width:0.0201 Z:0.0090 S:0.0090 (skipfill)
SR801;
PD.115,79;MM;MM0,25;MM60,118;MM-70,175;
AS1;VM4;BC;
MA342,342;
MA111,342;
MA111,111;
MA342,111;
MA342,342;
EC;VM3;MA241,342;# Exit
Eureka! Unsure of what I should actually try next (other than pestering Rick @ MakerGear to hurry up with getting the Experimental Filament Club underway), I thought trying to run parts using much smaller road widths (and not yet actually modifying the definition file) might be a good place to start. I noticed that using 0.007″ slice heights in Quickslice defaults to using very narrow road widths (0.0137″), so I thought I’d give it a try. In theory, making up for the reduced die swell by means of a smaller road width should result in not having drooping filaments on crosshatch infill…
And indeed, it worked like a champ, even with an extruder temperature of 270° C. and a 70° C chamber. The crosshatch infill (though still not quite as good as with OEM material, but the best yet with generic material) showed minimal distortion – had I let the part complete (would have taken 2 hours – the FDM 1600 sets no speed records), I’m sure I would have not seen any sign of sagging on the top surface. I still had significant curling on the part (and the curling that started on the left end of the part appeared to creep along as the build progressed), so the search for better ABS continues.
I think the ABS from Reprapsource.com http://reprapsource.com/en/show/6444 is probably a bit more like the Stratasys stuff. It is white rather than cream and has more die swell than the ABS I got from NIP. It also likes higher temperatures you are using.
Thanks nophead – I’ll see if they can tell me the exact formulation. Getting a spool of it would cost around $184 USD, so I’m not quite ready to dive in…
Great Stuff – what a helpful Blog!
The QuickSlice software is truely a POS, and the Asymtek drives a nightmare. Between the three (counting the FDM as one) I’m getting a lot of gray hairs. Like you, need to find a new source of software, material, support, and the other stuff these FDM eat up.
Now that my FDM is sort-of running, I’m rapidly running out of material and need to find some affordable sources or alternatives.
Did you ever try contacting SIBCO in Michigan (and also in Europe), as their web page (http://www.sibcoinc.com/fdm.htm#material) claims a Stratasys compatatible material & support. I did emailed them requesting pricing but haven’t heard any thing back yet, as I’m just a very small fish.
Keep up the great work……
Hi John, thanks for stopping by!
Actually, I’m learning to deal with QuickSlice – the only gripe I really have with it is that you have to group all your models into a single .STL before bringing the file into QuickSlice. It’s also still hackable – I understand the latest version of Insight software obfuscates the machine definition files by running them through a TCL compiler (so my tweaking of the flow curves would be entirely impossible). What version of QuickSlice are you using?
“Now that my FDM is sort-of running, I’m rapidly running out of material and need to find some affordable sources or alternatives.”
LOL! That’s exactly what prompted me to start down the crazy path of trying generic ABS, and spending hours at the university library, researching just what the heck this plastic stuff is…
I haven’t contacted SIBCO yet, though I did order two spools of ABS (normally pretty expensive, but they gave me a good price as they were the last ones they had, as they’re now just doing their ‘ABSmax’ material) from Argyle Materials (http://argylematerials.com/) back in September. Unfortunately, they never arrived! I finally called Argyle up this week, and they thankfully had a USPS tracking number, but all it could tell me was that it was ‘delivered’. I doubt that someone swiped it off of my porch (USPS and UPS leave stuff on my doorstep all the time, and nothing has ever gone missing), but USPS can’t do anything about it, and I’m out of a couple hundred bucks as a result.
I have run across mention of people being less-than-thrilled with the quality of 3rd party Stratasys materials, so it’s possible that I wouldn’t have been pleased with the filament anyhow. As it is, these third party suppliers still charge a pretty penny for their wares – were I using my FDM 1600 for a business, I’d gladly pay the 30% or so extra to get the real thing, given my experienes with the Chi Mei PA-747.
The new UP! printer from China (http://pp3dp.com/) uses 0.070″ filament, and initial reports were that the material ran very well, and was pretty close to Stratasys material. However, users have noted that recent shipments of filament have a much stronger smell when running, so I’m guessing that PP3DP may have switched suppliers or materials.
I keep daydreaming about ordering a pallet of MG94-NA1000 resin from SABIC and having New Image or Village Plastics extrude it into 0.070″ filament, but I’m not quite that brave yet…
HI,
I have been following your blog on and off for some time, and what interests me most is the ABS and HIPS material that you have been using from NIP. I just wanted to know whether you have been completely satisfied with the ABS (Polylac) material and I know that you had some issues with the HIPS from NIP. I wanted to order the support material from NIP but now I am unsure. What would you suggest?
Thanks,
Rich.
Rich –
In short, I wouldn’t recommend either one for use in a Stratasys at this point. Neither acts close enough to the real material to make me fully statisfied – both kick out a lot of vapors, are are extrusion grade materials. I think we may be needing injection mold grade plastics for use on a FDM machine.
Interesting finding your blog here. I have an Asymtek 201 with a 12×12 XY table that I have adapted to position a mototool for use as both a NC drill and an NC router. I hadn’t thought of using it for a rapid prototype printer but I’ve now placed that on my to do list.
I wrote a program to output ACL to the controller which reads excellon drill, NC G-code, gerber files, and DXF. So far it is working pretty well, but as I mess with one file type I end up breaking another. All in all though it works pretty well.
I presently have my controller opened up and am trying to reverse engineer the digital I/O board. Mine only had the ‘STOP’ signal stuffed, but I managed to wire up one of the outputs to drive a relay to turn on and off the moto-tool. I have yet been unable to figure out the digital inputs, but if you have that board and could take a photo of it, it would be helpful to identify the chip set they used.
Thanks for the useful and entertaining web blog.
geo
George – I don’t think I’ve actually had my Asymtek opened up yet, but I’ll snap some pics if I ever do. Make sure to visit John Branlund’s blog as well – he may have opened his up at one point.
George,
I just saw you comment in HaveBlue blog, and I’m interested in your program that outputs ACL — can you post some further info?
Also, there’s some manuals (at http://haveblue.org?p=514 ) that list some possible outputs and some diagrams on how to interface.
John
I have leveled a piece of used foam and measured the distance of a piece of 1/4″ glass to the nozzles to verify all is level. I then epoxied the piece of glass to the foam. I have been trying polymide tape which has not worked very well so I have resorted to blue painters tape which actually works but placement of the first layer is crucial cause if it doesn’t stick then it get a similar look to your picture above. Fortunately I still have some support material but I have been using ProtoParadigm for my ABS material which seems to work very well in the machine at about 263C. I have 3 heads so I can do some experiments although one does have a cracked inlet buffer. I am about to try PLA for the support material but I was wondering if anyone has figured out how to adjust the idle support to a temp less than the preprogrammed 210C. I am hoping that the PLA will stick a little better than the stock support material to the tape like it does in the Reprap world. I would also like to try PVA but there is no way to even try it if the support idle temp is 210 as that could cause some catastrophic results. Please let me know your thoughts as apparently these machines have a very small community. I am running an FDM 3000 and Insight 6.3
I’m guessing you should be able to adjust the idle temperature via the temp controller’s own setup. Unless of course the FDM is commanding the temp controllers over RS-485 or something. Have you asked John Branlund? His machines are closer to your 3000: http://3d4u.org/MyFDM/