Hans makes a build thread for a Rostock Max V2

[Hans]

I was able to get the broken thermistor to work temporarily, there was just a tiny nub of lead protruding from the epoxy and I was able to solder some wire onto it.

Calibrations are all done, bed is heating up for the first test print as I type this. Here goes nothing!

[Hans]

You take your time....

You follow the instructions...

You learn what things mean, and how they work...

And 100 layers in on the first try....

[img]http://siegecraft.us/wp/wp-content/uplo ... 00x241.jpg[/img]

Unfortunately, it popped off the bed on layer 115 of 124. Good enough to use though, until I get some red PLA to make it match the rest of the machine. My own fault really. The ABS smell was annoying me a bit, so I opened up a window (right behind the printer), and turned on the ceiling fan. Whoops!

-Hans

[geneb]

Do NOT print the fan shrouds out of PLA! They'll melt.

g.

[Hans]

All ABS here, meant to say red ABS in my previous post.... but yeah, definitely a great reminder!

Speaking of fan shrouds, I have a pair of them completed and mounted on the head. This is all TiT wiring, meaning "Temporary, in theory". Once I get the final fan shrouds printed, a repaired thermistor, and quick disconnects, I'll be re-wiring from the top plate on down.

[img]http://www.siegecraft.us/rostock/IMGP4465.JPG[/img]

Having some print issues to figure out. This is the filament guide funnel off Repables. The problem here came from from Slic3r, it wants to start adding a lot of infill blobs at certain layers, which shows up as these thick rings in this case. I can't get it to stop trying to do this infill. Trying Cura, but have been struggling to get the basic performance the way I want. It's running before the extruder and bed are up to temp, things like that. I think I finally have it just about dialed in, but keep having to tweak a bit here and there. The biggest problem I'm having right now is that I don't think my bed is level in the center. Having first layer issues where the nozzle is right on the bed in some sections, but air printing in others.

[img]http://www.siegecraft.us/rostock/IMGP4468.JPG[/img]

[Hans]

I'm finding this natural colored ABS is hard as hell to photograph during the day, too much ambient light from all the windows. Short version though is that I've worked through this latest set of issues. Re-did all the endstop calibrations, and z-height zero. This cured my level issue with the prints, and I'm getting a good first layer again now. Slicing the funnel with Cura eliminated the blobby issue from when Slic3r was trying to force the un-necessary infill onto the print. 5mm cube stack came out pretty good, except the very top cube. I thought I had a minimum layer time programmed in, looks like I didn't, and it was heat soaking too much on that tiny top cube from printing too rapidly.

I'm not a fan of how Cura handles bridging though. Just a perimeter and then going straight to the infill, of course it's going to have sag issues.

New thermistors arrived today, haven't ordered connectors yet.... soon.

-Hans

[Eaglezsoar]

All ABS here, meant to say red ABS in my previous post.... but yeah, definitely a great reminder!

Speaking of fan shrouds, I have a pair of them completed and mounted on the head. This is all TiT wiring, meaning "Temporary, in theory". Once I get the final fan shrouds printed, a repaired thermistor, and quick disconnects, I'll be re-wiring from the top plate on down.

[img]http://www.siegecraft.us/rostock/IMGP4465.JPG[/img]

Having some print issues to figure out. This is the filament guide funnel off Repables. The problem here came from from Slic3r, it wants to start adding a lot of infill blobs at certain layers, which shows up as these thick rings in this case. I can't get it to stop trying to do this infill. Trying Cura, but have been struggling to get the basic performance the way I want. It's running before the extruder and bed are up to temp, things like that. I think I finally have it just about dialed in, but keep having to tweak a bit here and there. The biggest problem I'm having right now is that I don't think my bed is level in the center. Having first layer issues where the nozzle is right on the bed in some sections, but air printing in others.

[img]http://www.siegecraft.us/rostock/IMGP4468.JPG[/img]

Hi Hans, just wondering where you got the stl files for the fan shrouds you are using.
I looked on repables.com and did not see them.

[Hans]

PEEK shroud
http://repables.com/r/140/

layer duct
http://repables.com/r/200/

Filament funnel
http://repables.com/r/289/

[Eaglezsoar]

Thank you for those links Hans!

[Hans]

I'm rapidly learning that if I ever have issues with the first layer, and anything at all looks un-even on it, the first thing to do is re-calibrate the end stops. And if I ever touch anything component mounted on the head, to re-calibrate the end stops.

That, and the honeycomb infill pattern in Slic3r vibrates the hell out of the head. If anything shakes loose, and I have to tighten it back down, I have to re-calibrate the end stops.

Would be great to incorporate an auto leveling system into this unit somehow.

-Hans

[Hans]

I need to look into a better way to calibrate temperatures. Dropping my ABS temp to 215 seems to have cured most of my blobbing issues, which seems as a quite low temperature. I think that having the threaded thermistor is skewing my temps, as the threaded fitting moves it a few mm away from the hot end instead of being embedded into it. I might go back to the RTV method of retaining it in the hot end.... or just pick up an E3DV6 when funding allows.

I'm also finding that having the thermistor extended out in the threaded fitting makes fan placement very critical. If a fan blows across the fitting that's holding the thermistor, it really makes temps go wacky. Heater goes full power, but the temp readout drops down to 175 or so, which I suspect is more that the thermistor is cooling than the hot end itself. This fan duct may also be an issue too, as it is directed more at the body of the hot end as opposed to the plastic itself. Will look into some different designs.

-Hans

[Mac The Knife]

You could insulate the thermister with a blob of high temp silicone. As for the temperature in general,,,, I bought a cheap digital thermometer from Ebay,,, found out my actual temperature was 8% lower then what was shown onscreen.

[Hans]

Found part of my blobbing/stringing problem. Looks like Cura doesn't retract at all unless you pass over a non-printed area. So any time the extuder does a movement over a printed area, it oozes and strings across the surface.... but if it moves across an un-printed area it retracts and everything comes out fine.
But I don't like a lot of things about the toolpaths coming out of Slic3r, and nothing else seems to handle non-manifold STL's as well as Cura.

So a lot of work to do still in figuring out some things.

-Hans

[Hydrolove]

Hans, going back to your power supply wiring, I like your idea of bringing out one large gauge wire and running it to a bus bar.Then being able to tap power from that. Is there a reason that I cant tie in both 12V rails to one bus bar? One large gauge wire from each rail combined to one terminal on the bus bar? That would also be a convenient place to monitor voltage and current also.

Kris

[Hans]

The two rails run off of different regulators, and I don't know what the capacity of the smaller rail is. Tie them together, and you could potentially draw too much amperage from the smaller rail and blow it out.

If you're going to go with a bus bar, I'd just feed from the larger rail.

-Hans

[nitewatchman]

Some large power supplies also operate only using a single 12VDC rail. I used a Cosair RM750 for this and several other reasons.

[Hydrolove]

I ended up going with the Cosair CX750 and opened it up to remove the nest of wires and replace it with heavy gauge stuff. That power supply is a single rail design also.
http://forum.seemecnc.com/viewtopic.php?f=6&t=6126

Kris

[Hans]

Been having some problems on longer prints lately, namely complete shutdowns. Screen dark, head stopped, and just dead. Cycle the power and it comes back on like nothing ever happened.

My suspicion is that the power supply is overheating. It can circulate the air within the lower compartments, but there's no real path for cool air to come in and hot air to go out. Been trying all week to print a 10" nose cone for one of my rockets and I am finding out that 9 hour prints are a great way to test out your printer. Latest attempt is running right now with the acrylic covers removed. We'll see if that improves things at all.

-Hans

[Hans]

Yep, pulled the acrylic covers off and it ran the full 10 hours without a hitch. I'll have to rig up a temp sensor of some type to see how hot it's getting in there.

-Hans

[Eaglezsoar]

Yep, pulled the acrylic covers off and it ran the full 10 hours without a hitch. I'll have to rig up a temp sensor of some type to see how hot it's getting in there.

-Hans

There have been some mods made that add (2) 92mm fans in the area where the acrylic is on both sides of the base.
You should be able to find these mods under the Mods topic off the main forum.

[Hans]

I don't think it necessarily needs any additional fans, the power supply already has a 120mm fan in it. Just that when you have the acrylic covers on there the air has no flow to it.
If the back cover is removed, and the front two get some vent slots in them, you'll have plenty of thru-flow and more than enough cooling.

I'll probably replace my front covers with perforated sheets of some type and call that problem closed and finished.

-Hans

[crocky]

Looking at the latest kits they have quite a difference in the air flow now on the base board, it has got two rear facing holes to rear of the power supply and three in front of the power supply. Someone has been listening

[Hans]

I think I've reached my limits with the stock hot end, and am eagerly looking at the E3D V6. The main issue I am having is still coming from the location of my thermistor on the threaded mount, it sticks out too far and using the layer fan just causes temps to go bonkers at more than 20%. But that 'temporary, in theory' crappy looking wiring job I did for the hot end and associated fans? Yeah, I need to clean that up first, and and also print out some mounts.

I'm also getting some lash in the mount where the arms meet the cheapskates. I need to look at that soon, probably going to add some washers under the screws that retain the axles to the cheapskates.

VERY envious of that new base bottom plate, with all the cooling slots. It would be way too much work to replace what I have right now, same to get in there with a scroll saw and add similar slots, so I have to basically run without the acrylic covers on a long print. Seeing all these changes to the melamine that deal with problems I'm having is giving me some mixed emotions. On the one hand it's cool seeing the upgrades that SeeMeCNC has done since I bought mine, on the other hand it sucks having the problems that brought about the changes.

[Hans]

Broke down and ordered the E3D v6, plus the .8mm and .25mm nozzles to go with it. I've been printing some pretty large and un-detailed things lately, so I want the .8mm for speed. But I also want to start pushing the detail side too, now that I'm getting back into some other hobbies again.

I'll have to check, I think I have some Deans connectors laying around, otherwise I'll pick some up for the hot end. The rest of the connectors I have some various small ones laying around I can use.

-Hans

[Hans]

Ok, time for a thread necro, as I'm having issues now, and it's been almost 3 years since I built this thing ...... so I can't wrap my head around certain things again.

My temps are out of whack on the hot-end. It's obviously cooler than the rambo board think's it's at. I had been printing at 225c for ABS without problem, but then I was having a clogging issue, and things were definitely running cooler than it was indicating. I compensated by increasing the set temp to 240c which worked for a while, but now same problem. Tried replacing the thermsitor. Went from bead to cartridge style, but still same thermocouple type, so no settings needed changing you would think. At least E3D says same type settings.

I set it for 225c, which the printer THINK's it's at, but reality is closer to 170c. So I need to make some adjustments there. The problem is also drifting, meaning I was able to compensate a while by increasing the set temp, and it was printing GREAT again, but now I'm back to printing cold. I wouldn't think the heating element is bad, as the printer THINK's it's at the temps I set.

Not sure what to do here. Not like I can pull the data from the RAMBO board, edit, and re-upload. But I don't think I have any copies of the original arduino sketch anywhere, and really don't want to start from baseline code, do I?

[Hans]

Well, uploaded the latest firmware version, made sure to increase the max temp (I think), made sure the thermistor is selected properly (I think), and man things sure are different. Interestingly, even if I specify I have a V2 with the non-accelerometer hot-end, it still tries to initialize the accelerometers.

However, didn't fix the problem at all. Still colder than indicated when at print temps.

May be a really really dirty threaded portion of the nozzle though, trying another one and it's promising so far. We'll see how it goes.