Strange issues with second Creator

[roykirk]

My second Creator arrived yesterday (the one I was talking about buying in another thread went back, long story). My old one is awaiting a replacement extruder set after some 1000 hours. I anticipated jumping right back in to printing with my second printer, but various gremlins are popping up that I don't remember ever having to deal with when I purchased my first Creator. My printing conditions are as identical to my first printer as I can make them. I even pulled the roll of filament from my old machine to use on the new one. Printing PLA on a glass bed covered with blue tape, 195C/50C (heated platform), 40/70 print/travel speeds. I started having trouble with the first couple of prints with corners curling up, models popping off, etc. Then there was weird printer activity. Twice so far when the machine has completed a print it just stops dead in its tracks instead of lowering the bed and going back to home position. I also can't seem to level the bed for the life of me. Yes, I've used the bed level grid from Thingiverse and I can get everything perfectly level, but run the script 30 seconds later and everything is out of whack again. While I don't remember having so much trouble leveling the bed as a newbie I'm going to assume it just needs time for the bed springs to get worn a bit. As far as the weird printing outcomes, there are a handful of things I can't recreate exactly from my old printer for one reason or another. I'd appreciate input or thoughts on what people think could be causing my problems -

- Kapton tape is still on the new machine's metal bed (with blue tape covered glass on top) while I had removed it from the old one long ago (maybe it's creating an extra layer of insulation?)

- Location of the new machine of course can't be in exactly the same location as the old one. I've noticed the new one is located fairly close to an AC vent. I've since closed the vent and I'm waiting to see if that makes a difference

- With my old machine I always sliced and created my x3g/g-code with Replicator G while with the new machine I'm using Makerware since it's easier for the dual extrusion I'm doing for the first time

- Since I'm using dual extrusion I can't use the heavy duty spring clips I used on my old machine to hold the glass bed down (a problem noted by people in other threads as the nozzles hit the clamps no matter where you put them). Thus I'm just extending the blue tape on the glass bed to tape it down to the heated platform the best that I can. It feels snug but maybe the glass bed is moving and messing up my prints?

Right now what I'm trying is blocking the AC vent and I've also kicked up the bed temperature 15 degrees. I'm in the middle of model 5 right now and 3 of the previous 4 were failures. Definitely frustrating. Any other tips would be welcome. The printer stopping dead once the model finishes is a weird one. Maybe a firmware issue?

[roykirk]

No go. Corners still warping up. Giving up on the duel extrusion, clamping down the bed, and going back to Rep G. Will try dialing the bed temp back down to 50c as well. Fall back to what worked before and go from there I guess. I'm thinking I might need one of those infrared heat guns from the hardware store as well. The bed temp could be way off from the old printer as well.

[Geoff]

No go. Corners still warping up. Giving up on the duel extrusion, clamping down the bed, and going back to Rep G. Will try dialing the bed temp back down to 50c as well. Fall back to what worked before and go from there I guess. I'm thinking I might need one of those infrared heat guns from the hardware store as well. The bed temp could be way off from the old printer as well.

I have never used a glass plate for dual extrusion raftless prints, so that is an unnacceptable reason to give up!

I'll be honest, if you have done 1000 hours in your old flashforge, troubleshooting this shouldn't be much different .. 50c on a heatbed is about the same as not heating your bed, you might as well turn it off.

[Mjolinor]

50c on a heatbed is about the same as not heating your bed, you might as well turn it off.

This was a lesson to me. My Stratasys has no heated bed but has a heated cabinet that is always 70c. I added heat to my cabinet but only to 60c. The magic temperature seems to be about 68c, below that any ABS item will depart from the bed, above that it will stay stuck. Lots of experiments were made to get that number. It is true for Kapton and blue tape, with or without hair spray.

[Geoff]

I have come to the realization that 3D printing in Australia seems to go alot smoother, and simply due to the climate.

I don't have a heated chamber, I have tried them but they made absolutely no difference and were an eyesore, so I don't use any chamber, all my machines print out in the open, sure I try and keep cold drafts off it, but they do not require special heating. I've seen people struggle for so long, then I look at where you are from, UK, where obviously the weather on average is a bit cooler than here (lol let's face it, if it's 20c you guys are down at the beach... that's cold for me! we hit it at 26-27c.. )

But on average, the humidity where I am is midway, and we have had little rain so it is pretty dry here.. The house does not get below 22c because we have a wood fire going in winter, and in summer it is usually 28-40c depending on the summer, so yeah it seem Australia is the place to be to 3D print..

And you sent us all here to prison!!!

[roykirk]

Finally a success. Went back to 50c on the bed and had to print with a raft...worked perfectly. I hate using rafts though, still need to troubleshoot. I know 50c seems like such a low temperature there seems to be no use in heating it at all, but I can definitely tell the difference just by feel. As I was saying previous I used to use no heat at all with my PLA, but as I started get to bigger prints I started having corners pop up and/or curl. Experimenting found that a 50c heated bed with blue tape worked perfectly for the big prints so I just stayed with it. One of the reasons why that slight heat may work for me is that we're having one of the hottest summers on record where I live near Seattle. My wife keeps the AC fine tuned to 21c and it's never allowed to get warmer than that. I've been thinking I might put the bed leveling springs from the new FF in my bench vice overnight to get a little bit of the "newness" out of them.

I haven't given up on dual extrusion quite yet, but I decided I was changing too many variables all at once and needed to go back to the last known working configuration to troubleshoot. One issue I'm having with dual extrusion is that some of the models I'm trying to build take up nearly the entire platform, corner to corner. Makerware wants to build those wipe "walls" when doing dual extrusion and it can't do that reliably when it's got little room to do so.

[curious aardvark]

sounds like the new one isn't heating the bed as much as the old one - so just put the temp up.

One piece of kit you might consider buying would be an infra red thermometer.
This is the one I've got - useful pieces of kit, cheap too. Also fun :-)
You do spend a lot of time initially pointing it at things to see how hot they are. Also if you've got a dog - odds are it'll go mental chasing the laser dot

IT'll basically give you an accurate reading on the relative bed temps.

I will add that I have so far never been able to print anything without a raft.
I figure when i get round to setting up slic3r with the right gcode and linking it to gpx I might be in with a chance. The first layer needs to go down hotter, slower and with a little more extrusion. Can't do that with makerware, but at the moment rafts are fine.
Just seems like a waste of plastic, but print wise they're pretty idot proof ;-)