antwonjg
Posts: 1
Joined: Sun Jun 19, 2016 3:48 pm

Extruder and Bed Dont heat at same time!

Sun Jun 19, 2016 3:54 pm

I have the Wanhao Duplicator 4s and when i use simplify 3D from an sd card, (this may be irrelevant) the print bed heats first and wont start heating the extruder until the bed has finished and stabilized. How can i modify the gcode or change a setting so that the printer will simultaneously heat the extruder and bed? This is super annoying and i'm new to gcode so i don't want to botch up the gcode trying to modify.

greybeard
Posts: 156
Joined: Mon Mar 02, 2015 1:23 pm

Re: Extruder and Bed Dont heat at same time!

Mon Jun 20, 2016 3:53 pm

Mcodes do what you need - change the temperatures to those you need...

M140 S92 ; bed temp heating 92C
M104 S260 T0 ; extruder heating 260C

M116 ; wait for heating of both
3D Print Parts
https://www.thingiverse.com/Still_Breathing/designs

ccg
Posts: 1
Joined: Mon Jun 20, 2016 10:12 pm

Re: Extruder and Bed Dont heat at same time!

Mon Jun 20, 2016 10:19 pm

uncheck the "wait for temp controller to stabilize before beginning print" in the temp page for the bed and the nozzle
then set it manually with the machine controls before the print

CompoundCarl
Posts: 2005
Joined: Wed Aug 05, 2015 7:23 am

Re: Extruder and Bed Dont heat at same time!

Tue Jun 21, 2016 8:39 am

I'm not sure the suggestion above will work, but here's what I've used in the past and it's working correctly for me. Just click "Edit process settings" and go to the Scripts tab. You will need to reorder one line in the starting script.

You want to change it from this

M140 S[bed0_temperature] T0
M134 T0 ; stabilize bed temperature
M104 S[extruder0_temperature] T0
M133 T0 ; stabilize extruder temperature

To this:

M140 S[bed0_temperature] T0
M104 S[extruder0_temperature] T0
M134 T0 ; stabilize bed temperature (MOVE THIS LINE)
M133 T0 ; stabilize extruder temperature

MontyFlange
Posts: 38
Joined: Tue Mar 24, 2015 7:21 pm

Re: Extruder and Bed Dont heat at same time!

Wed Jun 22, 2016 9:34 pm

You don't really want them to heat up at the same time. It can put a to greater load on the PSU.
FlashForge Creator Pro

PinballGeorgio
Posts: 94
Joined: Sat Apr 11, 2015 10:58 am

Re: Extruder and Bed Dont heat at same time!

Thu Jun 23, 2016 5:33 am

If the standard preheat mode on the printer also heats up the bed and nozzle at the same time, I wouldn't worry.

greybeard
Posts: 156
Joined: Mon Mar 02, 2015 1:23 pm

Re: Extruder and Bed Dont heat at same time!

Thu Jun 23, 2016 1:29 pm

It's worth reviewing M-codes...

If you use codes to 'wait' for stable temps, at some point (perhaps now) you'll find that until both bed and extruder are stable, the clock will tic, tic, tic...
This is because temps usually fluctuate +/- both sides of the set point (meaning if only one temp fluctuation occurs and goes one degree below set point you may not be a happy camper.

Consider my previous post (shown below) - M116 waits for both to reach setpoint but not stabalize (and you don't care if actual isn't spot-on). Put these in the Start code

M140 S92 ; bed temp heating 92C
M104 S260 T0 ; extruder heating 260C

M116 ; wait for heating of both

Here's a copy of my actual gcode script (for my DaVinci printer) (it also moves extruder forward for cleaning)

;-----------My Start Script-------------------
G28 ; home all
M116 ; wait for heating
G0 Y165 F700 ; move forward for Nozzle cleaning
G4 P4000 ; dwell for 4 seconds for cleaning
;--------------End---------------------------
3D Print Parts
https://www.thingiverse.com/Still_Breathing/designs

SteveThatcher
Posts: 2
Joined: Mon Jul 10, 2017 6:06 pm

Re: Extruder and Bed Dont heat at same time!

Tue Jul 18, 2017 10:52 pm

I happen to have a Wanhao 4S and I found the sequential heating a big waste of time. I actually found the answer elsewhere before I found this thread.

Modifying the startup script as another person mentioned (delete a few lines and add the extruder and bed commands) works perfectly. What I found is when I was experimenting, I deleted the wait for temperature commands in the original script and of course, found out the printer didn't bother to wait for the final temperatures. What surprised me, however, was when I went to the temperature tab and clicked the wait checkbox, I would have thought the code would have added the wait command somewhere, but it did not seem to. I ended up retrieving an older profile that had the original script in it and fixing the new profile I was working on.

jfkansas
Posts: 84
Joined: Wed Oct 01, 2014 2:12 am

Re: Extruder and Bed Dont heat at same time!

Wed Jul 19, 2017 5:57 pm

It isn't that big of waste of time, the build plate can take up to 8 minutes or so to fully heat and the hotend takes about 1-2 minutes. If you are doing hour to 2 hour or longer prints that is a small fraction of the time of the total print process. I can see it being a big time waster if all of your prints are 30 minutes, but then you need to think about putting more on the build plate at one time to maximize your make ready time efforts.

For ABS here is my workflow.

Preheat bed to 80c, this takes about 4 minutes max. I've never timed it.
Apply slurry
Start print
Bed continues to heat to 95c, takes just a minute or so.
Hot end heats, 2 minutes or so.
Print starts

A lot of times I will be finalizing my prep in S3d while the printer preheats.

You also really don't want your filament sitting there cooking for 6-8 minutes while the build plate is heating. The best scenario is the hot end heats and as soon as up to temp it purges, skirts, and prints.

wirlybird
Posts: 1216
Joined: Sun Jul 17, 2016 1:32 pm

Re: Extruder and Bed Dont heat at same time!

Thu Jul 20, 2017 7:49 am

I have to agree with JF. On some of my machines I am using glass beds and once the bed reaches temp the extruder starts but this gives the glass a little more time to come to temp and stabilize.
I also don't like the idea of the filament sitting and cooking in the extruder. Also heat is building in the extruder while it is sitting, hot, in close proximity to the hot heat bed.
I used to get impatient for the printer to heat but most of my prints are long so it really was a small bit of time. I adjusted my overall process where now I start the bed heating and then go back to getting the print ready and on the SD card. When I put the card in and set it to print it moves the extruder into place, heats and starts to print.

Everyone has there own way to do it so what ever works best for you!!

Return to “General Discussion and Tips”