[QUOTE="wackocrash5150, post: 33499, member: 17650"So that left me with PETG. Printed out most of the parts and what a PITA!!! Have to print SOOOOO slow and darn near bonds to the PEI, stringy as hell, likes to glob on the nozzel, but I eventually got it done. I'm surprised actually that people like printing with this stuff so much. Doesn't look the prettiest but it's functional.[/QUOTE]

What brand and temperature were you using? PET-G needs to print slower, but not that much. On my Printrbot Simple Metal, I print at 4800mm/min for PLA and 3000mm/min for PET-G. First layer at 245 and the rest at 240. There will be stringing. But I discovered that, in my case, some of it was caused by the slicer. I have been using Slic3r and I would have thick webbing between posts. When I switched to Simplfy3D for slicing, using the same retraction settings as I did with Slic3r, I get very little stringing.

 

Never had it change temps during a print but tried 235-245c and all in between, tried 40mm/s and had to go to 18mm/s using MG Chemicals black PETG on Cura.

 

If you can get it, try some eSun or Hatchbox PET-G. I had problems with with MG Chemical PLA in the past. Not sure what their PET-G is like.

 

You could be right. eSun is a bit pricey and Amazon.ca doesn't sell the Hatchbox PETG up here in igloo land. Lol

 

That's interesting. eSun is less expensive than Hatchbox here. eSun runs about $25 ($33 Canadian) and is very similar in price to the PLA.

HOLY S**T!!!! I just looked up eSun on Amazon.ca and they are ripping you off on the price! That is almost 3 times what it is here.

 

Check out this place....

PETG :: Solarbotics

They are the Canadian distributor for eSun. They show $30CND for a 1kg spool. Unfortunately, they seem to be sold out of it at the time.

 

Cool. Thanks Elmo. I'll keep that in mind when I get more.
I bought my Hakko soldering station from there a year ago and they were good to deal with.

Balance of extruder parts just finished printing off and came out very well with Hatchbox ABS.

 

A question though; I am correct in thinking that when all is said and done that, ideally, all parts should be ABS? Wether that means using PETG now and reprinting later in ABS, or printing ABS from the start where possible. I'm not looking for ludicrous enclosure temperatures. Just 30-45c to keep it warm and draft free.

 

PETG would hold up just as well as ABS. No need to reprint the PETG parts unless you don't like the color or looks. Functionally it should be fine.

 

I've had good luck with hatchbox petg, 245 and 70 for temps. Print speed around 45, travel at 170. Some stringing but much better than others. Drop temp to 235-240 for less stringing.

 

Do you have your extruder suspended above the effector on your delta? I just set mine up that way and it resolved all my long-standing extrusion issues on my kossel, and PETG now prints very cleanly

 

Mine is the "tratitional" below the effector. I'd be interested in seeing a pic of what works for you. Maybe try it out once the C-Bot is up and running.

 

I'll

I'll take a pic next time I'm at the printer. Here's the mod I used though: A-Struder by nebbian

The only difference is I used springs instead of rubber bands or bungie cords. If you have a lot of parts left to print I would recommend doing this first -- I wish I had. It takes all of half an hour to set up after the parts are printed and the difference is huge.

 

The only PETG I've printed is eSun magenta, and I print at the same speed I print PLA (50-60mm/s) @ 250C on a 60C bed, typically 0.4mm nozzle, 0.3mm layer height.

 

Did some new fan ducts for c-bot with E3D volcano, as didnt have enough clearance with the regular ones.

see Fan duct for E3D volcano and C-bot by percy_b

 

Yes. I realised this after fitting the plexiglass. No heated bed yet so not a big issue, but the 12v transformer could do with some more air for sure. Am thinking about tidying it up a bit.

 

Clamping glass to the build platform, any new ideas? Currently I use four, pretty strong alligator-clip like things to hold it down, I always figured it was good enough. I always figured I really only needed Z holding strength, not XY. Until recently that is: I've done a few big\long prints, and I've got some 'shifting' on a couple of them. All of a sudden, 20 hours in, the whole print has shifted:

RAAAAA!!!!! Why?

I thought maybe loose stepper wires. Then it dawned on me: I ran this via OctoPrint, and I had my time-lapse on...
Inspecting the time-lapse, I discovered the whole print shifted about 2mm back over one layer. And, I remember hearing a 'snap!' sound when it happened: One of those legs (a small one in the right front corner) had gotten snapped off at the same time.
My guess is that the nozzle, for whatever reason, collided with a leg, enough to actually move the whole print stuck to the glass bed, and snap the leg off in the process. It's only a .4mm nozzle. I got this sort of thing happen on my 1.2 volcano, but I didn't expect it here.

Super annoying for many reasons, but I'd much rather deal with a small feature knocked off on a large print than the whole thing being ruined by a shifted build plate. And I don't want to have to raise\lower my bed between every retraction, really increases the build time.
So other than clamps, is anyone using a better way to affix the bed on X&Y, to prevent any sort of slide like that.

 

dang man that sucks! perhaps you could print long enough to make some sort of u-channel molding style clip that spans from front to back on the two sides of the print bed that way the glass cant shift?

 

I have a 6mm aluminum tool plate bolted down on the arms and buildtak on top of that. Nothing is shifting on mine.

 

So, after much deliberation, I'm currently shooting rubberized undercoating on the bottom of my glass: This should make it nice and 'sticky' against the heated bed itself to prevent any sort of XY sliding, and maybe even provide for better thermal transfer qualities. We'll see....

 

What about something like this instead? I used these back when I was printing on a glass plate and they held things down really well

http://www.amazon.com/100mmx100mm-H...tsink+Cooling+Thermal+Conductive+Silicone+Pad

 

Looks like a good solution indeed: Is one side adhesive, or do you have to affix it yourself?

Undercoating has been applied, and I've re-installed the glass: With the clips on it, no amount of horizontal pushing will move that thing (in the past, it wasn't that hard to move the glass around actually). Hopefully that'll resolve my issues in the future.

And be a warning to all others that pass through these gates.....

 

It is adhesive by surface tension. Set something on top of it and you won't be able to slide it around on this stuff. So if you ever need to take the glass off, you can lift it off without damaging the glass or the pads and use them again later.

 

After much struggling due to my own bone headed mistakes I have finally got my C-Bot together and working properly. It is a hybrid between the original and the rework as I had started the project before the the rework bill of materials was posted. All of the printed parts are from the rework files but I had already cut the aluminum so I was stuck with the old positioning for the z-axis motors. Now all I need to do is decide whether it is worth it to move over to the RADDS+DUE I have or stick with the RAMPS I already have it working with. Either way I need to do something about the cable nightmare I have going on atm as it is wee bit unsightly.



My poor little Maker Select is just dwarfed by the thing in that picture.

 

Hi All,

Getting my printer calibrated and reliable, and still struggling we these imperfections during printing.

Gut feeling is is extrusion but have calibrated 100mm of feed exactly. Any suggestions?

 

* Filament slipping in extruder?
- Check to make sure the filament coming out of extruder has the lines from the mk7 / mk8 but is not squeezed flat and does not have any obvious signes of slippage. eg; shaved spots and / or plastics dust / bits.

* Consistency of filament diameter.
- Measure in multiple places and multiple axial locations in same spot. Average them all out, enter that into the slicer.

* Partial blockage in nozzle / hot end.
- Extrude plastic in air, see if it curls even after a little tug.
- Check roundness of extruded filament.

* Extruder motor skipping steps.
- Watch extruder spin, look for obvious signs of skipping while extruding through hot end.
- Measure voltage of extruder driver. What drivers are you running? Can give you a ballpark voltage based on that.
- Check temp of extruder driver. Again what drivers?
- Ensure extrduer driver is not doing a quick drop out due to heat. Some drivers can over temp and shutdown then return fast enough you won't notice, but will skip a step as a result.

 

@Carl Feniak Ok forgive me if this has already been posted/asked but I've been through about 20 pages and didn't find anything and figure the faster approach would be to ask but if I'm wanting to get a working area (aka the actual printing area) to be 15x15x15 inches, would I just plug about 16 inches (converted to mm of course) into the C-Bot Cut Calc? I'm not so certain on if the C-Bot Cut Calc is the working area or just strictly the bed area so I want to make sure.

Next and final question would be, do you see anything wrong with a 15x15 build platform? As in, in your experience would there be a big disadvantage to it such as the weight causing issue or the structural support of the machine would be questionable?

Thank you!

 

The cut guide is for the hole-to-hole distances of the build plate

It has been recommended that for larger than 12sqin platforms 3 leadscrews be used and the back bed support extrusion by the rollers be 20x60

 

If you're running three leadscrews, I wouldn't think you'd need 20x60 for the z-stage support. Two, or a single cantilever, and perhaps a 20x60 would be needed, but in a triple screw setup, the support is largely just keeping it centered.

 

If that's so, then is there a decent way to calculate the actual work area of the printer?