ABS - Ultimaker 2 - Unsuccessful

[timelapse 0]

Hello all,

I'm on my 4th day using a new Ultimaker 2. So far, everything has been working flawlessly with PLA and even Bridge Nylon (custom settings). I have done about a dozen prints with great success.

Today, I tried to use ABS for the first time. I switched from PLA to ABS. I'm using black, Pro-Series ABS from Matterhackers (I'm in the US). http://www.matterhackers.com/store/3d-printer-filament/pro-series-black-abs-filament-3.00mm. It is advertised as 3mm, but when I take measurements it's really around 2.9mm.

I started with the default ABS setting on the Ultimaker. It loaded fine, but the stream of ABS exiting the extruder was very fine and looked off from what I had observed with the PLA. It also didn't drop down with gravity the way it should and instead it curled up and stuck to the nozzle. I unloaded the material and eventually realized that I had ABS remaining in the extruder. I have followed the steps (removing the bowden tube, using a hypodermic needle, etc) for fixing this 5-10x via posts on this forum. Finally I got it unclogged. This was after 2 hours of frustration.

I'm determined to print ABS, so I tried again. The exact same thing happened and now I'm back to trying to remove all the ABS material from the nozzle. I'm about to the point where I would rather just send a file to Shapeways for Selective Laser Sintering and wait 2 weeks instead of wasting hours trying to unclog the Ultimaker 2. Then again, I know it should work and I'm probably doing something incorrectly.

Where did I go wrong? From my research, the ABS should work fine assuming it's under 3.1mm max. I specifically purchased the Pro-Series ABS because it has good tolerances and shouldn't exceed 3mm according to the data sheet.

Any tips or suggestions would be greatly appreciated.

If there is a known issue with the Pro-Series ABS from Matterhackers, can someone recommend where I can purchase ABS in the States that will work with the Ultimaker 2?

Thanks in advance.

 

[kris 29]

The same happened to me when changing from PLA to ABS. Clogged the nozzle which led to heavy underextrusion. I had to completely take the extruder apart (carefully!) and soak the nozzle in acetone in order to clean it.

Something happens when the ABS gets mixed with the residual PLA. I am sticking to ABS now.

 

[timelapse 0]

Very interesting, Kris. I'm surprised to see that my ABS filament clogged immediately the second time I tried to use it after thouroughly cleaning the original clog. I'll repeat the process a 3rd time and see if it works.

 

[gr5 2,167]

1) I haven't had problems with ABS but I'm less experienced with it so I was very careful about the temperature. ABS can bake into a clog much more easily than PLA. So what was your nozzle temp? I have been using only 245C as I'm afraid to do any other temp. Also you should not let the nozzle stay at that temp ever without extruding (e.g. during bed warmup) so I always warm the bed first. My bed was at 110C I believe (I can check my notes if you want).

I think that's the most important thing.

2) If the filament reaches 3.01mm then you have a problem. I would test it with calipers. If you don't have metric calipers I recommend you get some. They are an extremely useful tool and practically required for 3d printing and especially for doing CAD.

3) I am also in USA and got my ABS here: ultimachine.com

 

[gr5 2,167]

Also I printed with fan at 0% for entire print. This is recommended for ABS to get good layer adhesion/bonding. Most of the many differences between ABS and PLA have to do simply with their different glass transition.

But this fan thing may be relevant as blowing air on the nozzle cools it for a bit until PID eventually compensates.

 

[timelapse 0]

1) So what was your nozzle temp?

 

I have been using the default ABS setting on the Ultimaker 2 -- which is 260. I'll manually bring it down to 240 and try again this evening. Looking at the specs for the ABS I'm using, I see 230-240 as the recommended temp. Why does Ultimaker default the ABS setting to 260 even though lower temps work better?

I do have metric digital calipers and the ABS never exceeds 2.9mm, so the specs appear to be accurate (2.9 +/- .005).

Thanks for the help.

 

[gr5 2,167]

Why does Ultimaker default the ABS setting to 260

 

Not sure except they aren't as experienced with ABS as their first printer didn't have a heated bed so ABS is kind of new for them. I mean many of the employees print ABS likely but mostly it's been PLA.

Daid probably did some research but got some bad answers. Not sure. Or maybe 260 is usually fine but I doubt it.

 

[timelapse 0]

Good news! I'm successfully extruding the ABS. I'm still on the early layers of the brim, but this is further than I got the last 2 attempts. Turning the temp down to 240 and manually turning it down to 0 while the heat bed warmed up to 100 degrees seemed to work well. Fans turned to 0%. Great tips, gr5.

Unfortunately, before I could finish typing this I have noticed the initial brim layer isn't sticking to the glass anymore. I'm using a glue stick and I also have it warmed up to 100 degrees. The first layer was fine and then it all pulled loose and started to make a mess on the build plate. Aborted.

I'll raise the build plate temp to 110 degrees and see if that helps. Maybe I should also slow the speed to 20 or 30mm/sec for the initial layers?

 

[gr5 2,167]

Was the brim squished a bit into the glass? It should be and there should not be gaps between the brim lines.

Instead of the glue which works, it's better to use either hairspray or abs juice (google abs juice). Make sure you clean the glass well before switching glue type.

I use this type (blue - unscented) as my wife also uses it to remove stains when doing laundry:

 

[timelapse 0]

I have read about the hairspray and ABS juice, but I'm quickly beginning to think ABS isn't worth the trouble of all the added build plate hassle and ventilation. I was ready to throw my spool of ABS in the trashcan after multiple failed attempts last night. PLA and even the Bridge Nylon has been so easy to work with compared to the ABS.

During my ABS attempts last night, the brim layer does have gaps between each line and the adhesion is awful.

I'll give the hairspray a go today. If that doesn't work, I might skip ABS printing altogether and send my critical parts to Shapeways for their SLS polyamide-12 (nylon).

Thanks again for the assistance!

 

[gr5 2,167]

the brim layer does have gaps between each line an

 

So probably you need to move the nozzle and bed closer together. I don't recommend re-levelling - just turn all 3 screws counter clockwise (looking from below) to raise the glass plate slightly. Maybe 1/4 turn and if the gaps aren't gone turn it a little more while it's printing the brim. Also more brim might help I think 10 passes/loops is usually enough but strange enough - 20 is better than 10.

 

[gr5 2,167]

Oh and bottom layer should be .3mm thick - that's the default in Cura.

 

[timelapse 0]

I'm currently printing with Taulman Bridge nylon using the hairspray and an adjusted build plate (closer to the hothead extruder) and it's working better than before (when I thought I already had perfect results with "Bridge").

Is there a reason why I couldn't use hairspray for all filaments? Would it simply be overkill for PLA?

 

[gr5 2,167]

why I couldn't use hairspray for all filaments?

 

I haven't experimented much at all with "glues". I just follow other's advice. glue stick or wood glue mixed with water and painted on work incredibly well for PLA (on rare occasions it sticks so well it removes a tiny sliver of glass!).

hairspray or abs juice works very well for ABS. I think you can mix and match these products somewhat but not sure. I did some experiments actually with different temperatures and with the glue stick here:

http://umforum.ultimaker.com/index.php?/topic/3404-printing-on-glass/

It was very informative - basically there is a sudden temperature change where it sticks incredibly well above a certain temp and horribly below the temp and it doesn't matter how much above or below the threshold you are.

 

[timelapse 0]

Excellent testing, gr5. I'll have to try PLA without a glue stick next time.

For now, I'm hooked on how well the Nylon Bridge material from Taulman is printing with hairspray. It leaves such a smooth finish on the bottom layer. Far superior to what i was getting with a glue stick and I no longer need to use a brim. The object pulls right off the build plate at the end with ease. I'm keep the HBP @ 95 degrees throughout and letting it full cool before removing the print.

I'll give ABS another try in a few days. For now, the Bridge material is my new go to. Crazy strong, easy to print, and with the right fill material on larger prints, the flexibility isn't a big issue when you need a semi-rigid part.