Solid infills - not so solid

[cquinby]

I am going nuts here and can't figure it out.

For the past week I have not been able to get solid infills (ABS or PLA), there are gaps between the tool paths and I have checked everything (except one, will get to that later).

I have re-calibrated the extruder multiple times and can get consistant 100mm runs to within 1mm. I have tried to reduce the nozzle size in slic3r and that is not making any difference. I have tried to reduce the extrusion multiplier and that is making no difference. Tried raising temp on the extruder, tried lowering the temp and neither made a difference. Tried to slow down the infills and nothing... Put new nozzles in, replace teflon tube = nothing.

I have one last thing to check and will do that tomorrow while it is pissing rain since I can't go ride a bike (why even take vacation here in the NW). That one thing is backlash again. I think the machine may be loosing up a bit since I have run it quite a bit. I am starting to see corner over-shoots and such which is a tell-tail sign of backlash creeping in again. Maybe I need to get some cross braces installed too since I widened the machine for the hot bed...

Anyone have any ideas, I am all ears!

[Chris Muncy]

Chris,

Can you post a pic? That will help a lot.

[cquinby]

Ya, I will try and take a good image and post it. I'm currently trying to get my heatbed leveled, opposite corners of the pyrex glass are not level and it is driving me nuts! Once I get that fixed I will fire off a print and get a picture.

[Chris Muncy]

Business cards work well for me

[Dave_Sohlstrom]

I was having trouble getting every thing level also. I rigged a dial indicator to the extruder and checked to see if the X axis travel was parallel to the Yaxis I did this at the rails not the table. It took a while adjusting the z lead screws so it was right. After that I used the indicator in both the X and Y to get the table right.

[cquinby]

Yes, had to use business cards but used them under the cardboard insulator so the PCB had no air gaps top or bottom to transfer heat better.

I just re-calibrated the whole machine back to inches and testing right now. So far the infills look better but will be a few before I can verify. I also think I may need to get a seperate supply for the heatbed, it takes for ever to get up to temp and the max I can get on top the pyrex glass is about 105c and that takes a good long time to hit.

Good news is the rain is coming down so I can sit inside and play more!!!

[Chris Muncy]

105c should be plenty for the bed. But if it's taking a while to get there then yuppers, time for another power supply.

[cquinby]

Chris,

The ABS just begins to stick well but I have noticed I don't have even heating on the glass plate... I have a shift of 15 degrees F in different areas... I think I will run out ot my shop and see if I have another PS to try. More wires to deal with....

[cquinby]

Problem solved.... The PS has enough juice... It was that dang 40mm fan I added for PLA printing. There was just enough air current to cool off the plate by dang near 40 degrees F in areas. Turned that off and now have pretty even heating and up to 110c!!! Yes....

[mhackney]

Wow, that is a lot of cooling! I'll have to check that on my bed.

Cheers,
Michael

[johnoly99]

The other guys are pretty well on it with the solutions. Triple check your extruder calibration, then triple check the triple checking. If you change colors alot (like we do) use ONE color for all your calibration of your extruder. Then, when you switch colors, use the extruder multiplier to "tweak" the extrusion amount until it's the same as the base color you calibrated with, and SAVE that configuration as say, Yellow_ABS etc...

[mhackney]

That's a great tip John and one I plan to document in the Operations Manual. I've been doing that too since I noticed a big variation between my orange, blue and green ABS with respect to extrusion temperature. It will be very useful to be able to capture extrusion temperature too and have that set in Mach. However, if you enter the temperature and bed temperature on the Printer and Filament tab in Slic3r, it will output the M codes to the gcode file. You can then look in the gcode display and see what temperature you need to set as you can see here!

cheers,
Michael

[johnoly99]

Good idea Mike! To anyone reading this, I'd say lets get in the habit of setting the temps in the slic3r boxes now! We can always comment out those lines in the G-Code until we come up with the custom Macro (M-Code) but it would do alot of good to know what temp you posted the code for, and if you make changes, you can go into slic3r and update the configuration so you will know.

Yes, even in the big injection presses, color makes a difference in temperatures and pressures. Natural is a good place to start, as with no colorant (Which is a contaminant BTW) it has a great starting point to learn as you go from there to all the different colors. The hardest one i've seen is the red. In many different things, red is the hardest because it takes the most pigments to get a deep red color, so it has the most "contaminants" I guess?

My $0.02