Big print--please comment/suggest.

[GPriv]

Hi, All--
I got everything up and running (cooling, heater box, no viruses on 'puter) and pulled off a 16-hour print. (see results below).
Facts:
Bed temp is set at 80; fluctuations between 78-81. Extruder is set at 230; fluctuations between 228-232.
The raft/skirt didn't appear to lift (much) during printing. The curvature (up, from the base) seemed to all set in when printing was completed and I turned off machine.
Same situation with separations (de-lamination); those splits came in the cooling process.

The 45 degree angle had no supports during printing. Running a straight edge along it I am somewhat "amazed" how clean the end product is.

For purposes of of prototyping I consider this a huge success. However, I would like to make it better. Suggestions? Big Thanx in advance.

The raft/skirt placement on bed.

size comparison

the print

[0110-m-p]

Could you post some more info? Most notably, print speed, layer height, material type/brand (I'm going to go ahead and assume ABS though), and bed adhesion method.

Are you printing with your layer fan on? If yes, turn it off for ABS.

Layer separation is usually fixed by any combination of slowing down the print speed, ensuring you are not in a drafty/cold room, and increasing the nozzle temp.

For ABS, I would run the bed at at least 85-90C if using hairspray or glue stick for bed adhesion. I've only had temps around 80C work on different build surfaces like Buildtak or PEI.

[Agisis]

Agreed. Need more info. I've printed very large ABS items for that length of time but have not seen that happen. You might also share what brand of ABS filament you got and where you got it. Not all are created equal, and sometimes you can just get a bad set of filament. I doubt that is the case here though. The good news is that I promise you that without a doubt, you will be able to print that with much higher quality the more experience you get under your belt with printing. Have you used any calibration STLs? There are some on repables.com that I use. I'm still new compared to a lot of folks here, but I can tell you that the quality of my prints increased exponentially each week that I really sat down and went through calibration print tests until I was really fluent into what each setting meant and did. You can export the Material and Quality settings from Matter Control and post them if you want so we can look at them.

[GPriv]

Thanx, you guys!
I am using ABS from matter Hackers. 1.75 There's no label on the spool for more info.
Here's the info that I derived. It may be duplicated.
Please let me know if you need something specific.
I think the nozzle is too close to the bed. The first pass comes out near perfectly (consistent line in thickness) but it's kinda flattened. I just looked thru instructions and see that it may be too close. Also, the nut atop the extruder holding it in place is loose, as is the extruder end (bottom--the actual nozzle). I'll heat up and tighten.

I had removed the fan on the extruder entirely. It was wreaking havoc on my extruder temp. After a while the extruder would not climb above 220ish; Matter Hacker guy said to disconnect it and see if that helps. It did, so I removed fan and shroud.
I use purple glue. Seems to work well when I put a nice even coat. I'll increase bed temp 5 degrees.

Again, thanx!!!!

Vent side -- open for air ventilation

Fan side. The air remains cool and has lots of volume down below for the brains of the printer.

[Agisis]

OK. A few observations (hopefully others will find better suggestions than mine).
a) I use Matter Hackers ABS in a variety of colors both solid and transparent hues so I don't think it is vendor.
b) Your settings look mostly fine:
- For something that large, I might suggest a little more infill though (say, around 35%). When it is cooling, if there is not enough infill to ensure the cooling parts are laminated to other parts, they can warp halfway through the print. Too much infill and you have the opposite problem where the inside stays hot and the outside gets cool and warps. ABS is fun stuff. Lol.
- Also, I prefer to have my perimeters set to about 3 or 4. It adds a lot of wall strength which can be important for tall thin things, especially when cooling ABS.
- I did not see all of your print speeds. To add them, select them in your Quality filters at the top of the Quality pop-up. Each one you select will get added to the list so that you may override the settings in Matter Control with your saved configuration. I hope that makes sense. Without seeing those though, I can't tell how fast your non-printing move actions are for the temp you are running, etc.
-
c) You shouldn't have to remove a fan to get it above 220c. Anytime you have to remove a component to make it work, then something is very wrong with the situation.
d) Some other thoughts:
- Have you verified that the temperature it reads at is actually the temperature it is at? It is possible your thermistor has loosed and shifted out of place, or is possibly pushed too deep, or your resistors are not getting enough contact, etc. Basically, your hotend (not extruder) should have no trouble getting so hot as to melt the stock hot end and it should do so very quickly, like in under 5 minutes tops.
- I have read about the enclosures, but for what you are printing, it should not be needed. I say this because I have printed several things that size and that tall in ABS with no enclosures in a slightly drafty room. This machine is not that sensitive, so I am suspecting there is something else going on. Then again, I just might be lucky. I only use the purple glue sticks. Love em.
- Check your extruder where the filament feeds in. There are several screws there, and in particular, the one holding the clear portion to the extruder. If that gets loose, the filament can get all bent out of shape during retraction and can cause some pretty novel outcomes in your print, few of which I have found to be desirable.
- 220c is not hot enough for good lamination with ABS, even with the fans off, etc. You really should be running at about 230c+ or it's just going to pretty much fall apart unless you go reeeeeeaaaalll slow with your print. I think you know that, but I was't sure what temp your print was done at. 220 won't cut it (at least in my experience).


Those are my thoughts based on what I have experienced. I hope someone else has some good input.

[GPriv]

Infill---hmmm. I'll try it. Not concerned with strength, tho'---only the top portion (the thick portion, as this will carry all the weight). Watching it print I was impressed with the tirangles and amount of material. Again, this is a prototype "thingy" that will ultimately (I hope!!!) be mold-injected... so, all this preliminary stuff is just measuring, dimensions, angles, lengths, etc.

I love tinkering with the printer, so I may as well get it alal right on. LOTS more printing ahead with the same baasic shape--only MUCH longer. So getting all right is important.
i'll try the perimeter. Not sure what this is, tho. The walls are set at 2mm. Gonna increase to 3mm on the next print (same shape without the 45 degree angle at one end).

"...220c is not hot enough for good lamination with ABS, even with the fans off, etc. You really should be running at about 230c..."
FAN- when I first start(ed) machine it would power up to 230. But if it remained on for say, 10 minutes, it would not get above 225...then 220...then 218ish. The wires' resistance was okay and uniform. So I called MatterHackers (purchased printer form them) and the guy said to try running with fan off. I did. It worked great so I removed fan and shroud as I have no plans to use PLA. If I ever do I will F with fans then. *-)
My temp set is Bed 80/hot end 230.

The enclosure seems to be fine. It was EASY. It's a carboard box that happened to be the right size.
The fan for the brains (base station) is mandatory and awesome.

"...Check your extruder where the filament feeds in. There are several screws there, and in particular, the one holding the clear portion to the extruder. If that gets loose, the filament can get all bent out of shape during retraction and can cause some pretty novel outcomes in your print, few of which I have found to be desirable...."
All seems to be fine regarding the above.

Trying to figure out the speed info for you:
(if you click the picture it gets larger. click again (on the screen that pops up to increase further)

[Agisis]

yeah, all of those. Those give you the ability to really nail a particular filament/brand and store it. I break mine up into a naming convention like this:

ABS-MH-CLEAR-0.5mm-STD
ABS-MH-CLEAR-0.5mm-FINE

where MH is Matter Hacker, 0.5mm is my nozzle in case I switch to my 0.35mm or 0.7mm (they behave differently too and require tweaks to your settings). I store the various speeds that you see in that drop down instead of leaving them as configurable for each setting through the main screen. Each brand you get, and each color you get is going to react differently. I have a black PLA from one company and a black PLA from another and they behave nothing alike. So, muck around with it until you nail the settings, then you will have ones that work forever whenever you use that particular filament.

[GPriv]

I bought five rolls of ABS at time of printer purchase--so I'm awash in the same stuff (different colors, however).
I will keep my .5 extruder as this is good for my purpose. I'm not printing anything fine and intricate--only big prints like that thing I posted. The wall thickness will increase--as I said because I need to maintain concern with strength (for dead weight).

Here's the info:

[0110-m-p]

In general speeds look ok, especially if you are printing inside that enclosure. The only speed that you might benefit from changing is the "Outside Permiter" which I run much slower than my normal print speed (60% if I remember correctly).

Only other tips I have that Agisis didn't touch on the fact that ABS in different colors (even from the same supplier) will require different temperature settings and you should verify your first layer thickness is correct (z-height calibration).

Also, you should read this post by mhackney before going much further. You'll likely find some random tidbit that clicks and fixes a lot of issues.

http://forum.seemecnc.com/viewtopic.php?f=36&t=7361" onclick="window.open(this.href);return false;

[GPriv]

Thanx!

[GPriv]

I'm test printing another go at the big print object.

The hot end drags on the printed material on some passes. Very odd. The first few layers came out near perfectly. I was very happy with the consistency of the extruded material, etc.
But, as it gets higher in the layers I see (and hear) the tip dragging on one section (only) of the print. I had tightened all screws, gave a thorough general check, re-calibarated Z height, and the three towers, the PID, etc.

Why would this happen? And, when it is on that side of the print (and drags) the feed motor for the material seems to "skip" like it isn't getting hold of the material--I suspect the material isn't moving through (getting stopped up by the tip drag) therefore cannot move freely and the motor just chugs along.

It ONLY drags when doing the long passes from one end to the other--and it doesn't always do it. Some passes are fine. And, only in one direction. If it's making a pass in the other direction it is fine.

Is this a "layer height" thing? mine is st at .2. First layer is .3

Thanx in advance

[Agisis]

I don't think it is layer height. My first thought was making 100% sure that the height of the hot end off the bed is exactly the same at the maximum edge of each axis. I had issues early on where I did not calibrate that as well as I should have with the limit-switch screws. The hot-end as it neared my Y Tower would get very close to the plate, but the opposite side was a bit too high. After fixing that, my larger prints dramatically improved (both in success rate and in quality). I found eye-balling it isn't really good enough. I would print a big 7 1/2" Y shape only 0.25mm thick and make sure that it was consistent across each axis. You quickly get a feel for how accurate it is when it makes the skirting.The only other thought I have is that maybe one of the belts is not tensioned correctly, and that could cause it not move the amount it needs to (occasionally) across one of the axis.

The extruder motor skipping can happen if you are trying to push too much material through at once, or if your retraction rate is so high and fast that the chews up the filament. I've also had that happen due to the screw I mentioned earlier that goes on the clear plate. Also, if you are doing a lot of retraction (say, with every non-printing move or every 0.1mm), the filament can get pretty hot in the extruder because that motor heats up really hot. That makes it softer than it usually is and the Extruder can chew it up and snap it. I've not had that happen with ABS though, only PLA. Um..what else...I think a 0.3mm Z-height on move may be a bit low. You could try 0.4mm or 0.5mm.



Just a few ideas. It's hard to tell without actually seeing it in operation. Your speeds look fine to me, so I don't think that is it.

[GPriv]

I'll check the belt tension. This is what I was leaning toward after I started another big print and watched closely till my eyes were buggn' out.
I was damn sure my leveling was spot on. I use a feeler gauge. My first couple of passes on the glass are beautiful--the extruded material. Very consistent.

Not sure what the retraction is.
I bumped up the layer height to .5.
"...I think a 0.3mm Z-height on move may be a bit low...."
You mean the first layer?

Thanx

[GPriv]

So bummed..looking at print (still have 15 hours to go) after 10 hours--there's a huge gap in it (same print as the previous big print).

Here's a pic of the ABS spool. Upon closer inspection I see ABC is imprinted on spool.

Would setting hot end at 235 degrees (up from 230) be the next move? Remember, this is being printed in a box--no air drafts.

[teoman]

That fan looks very big and industrial...

Make sure it does not induce any excessive vibrations to your printer.
Also, you can never seal up everything perfectly, it could be blowing a bit of air from under the bed to the printer.

[GPriv]

Thanx, T

The fan is smooth as a baby's bottom. It is set on LOW...so there isn't a ton of pressure--just a lot of volume. I sealed up everything pretty well--including the "draft holes" for the power supply (in the base plate of printer).

[Agisis]

I still think those gaps are cooling issues. Those are clearly hard corner warps to me. The torque of the warp is causing it to de-laminate. ABS is very prone to that. Running it hotter would likely help. My view has been that if i am making a solid piece that doesn't have a lot of jumps and stringing isn't going to be a worry, I will run it as hot as I possibly can (I may need to speed it up a bit too). That gives you the best component strength. Higher Infill and thicker perimeters also help body strength, but that is clearly a delamination warp to my eyes. I could be wrong though.

One way to cut this problem in half is try printing it with PLA. If there is no separation, then you have a materials issue and not a calibration/vibration issue. That may get you to the answer faster than anything else. Just a suggestion.

[Agisis]

One other thing to mention is those corners should be significantly sharper and cleaner than that, so I do think there is something else going on too, but I don't think it is related to the warping.

[GPriv]

when print is finished I'll check belts and report findings.
thanx!

[Brazz]

I'll throw my experience into the pot.

I had that exact style of separation when I first did a big print with thin walls on my Rostock Max V2. My fix was to set my hot end to 235 and my bed to 95 (which has resulted in nearly no separations mid-print from the build plate). The second thing I did was to get reallllllly psycho about my first layer. I ended up printing off things in one and two layers and then measuring for uniformity. In the end I calibrated it to print within a .02-.03 tolerance in the first layer height. After that, I actually had worse bed adhesion so I lowered the z-height by a good .03-.05 and have had really good results since then. Also your issue with the separation is probably 100% a temperature issue. The first layer height would only be an issue if you actually have a lot of curvature left in your calibration.

[GPriv]

I think you are right on the mark, Brazz.
Below is pics of my last print. It works for my prototyping purposes (the reason I kept at it) but it is a bummer to see the flaws, to be sure. I ultimately MUST get it right for aesthetic purposes--down the road.
1) I realize that the one problem with the tip dragging on one side of the print (when it climbs high above the bed) is because the print is quite literally lifting UP... therefore....
2) I have the first layer height psycho-bug as you. I really got the level height nearly perfect (I forget the lingo/actual name).

3) Question: the belts seems okay--the tension. Anyone have a suggestion on how they determine the optimum tension for their belts?

Not sure why it lifts like that--so I'll try cranking up the heat.
This is 9" tall. I will need to rise another 3" in total for the final product.

[teoman]

Make a bigger skirt.

[GPriv]

I peeled the skirts away for the pics--and unfortunately, they got tossed last night upon clean-up. It is quite large...but I may attempt MM ears.

[Agisis]

Ah ha. I couldn't see from the first set of pictures that it was peeling off the bed. That is easy to solve. Add mouse ears to your print anytime you use ABS with sharp corners. Mouse ears for something like that should be about an inch across or maybe a little more. I don't print anything thick using ABS without them. The larger skirt may help, but surface area on those corners in particular is super important when using ABS. Higher bed temp will help too, but compared to the melting temp of ABS, going from 80c to 95c is less than a 8% increase. I provided an example of mouse ears below:

http://www.thingiverse.com/thing:973415" onclick="window.open(this.href);return false;

[GPriv]

Righto on the mouse ears. Will try--how thick? 3mm?
Bed temp is 85 now.