What mods would make the heat bed and the hot end heat faster?  

Re: What mods would make the heat bed and the hot end heat faster?

Hi David,

some say the powersupply that prusa provide, is working at the edge of full load during initial heating.

speeding up the heating means something like:

1, increasing the voltage to the hot end and heatbed, this will stress the hot end, heatbed and power supply... the power supply may need changing...
speed increase is likely to be limited

2, insulate the lower side of the heatbed this needs to be high temperature insulation, cork may do... i suspect the hot end already heats up faster than the heatbed, so rather than delay the hotend heating to prevent bed levelling blobs, consider using the heater as it is, this will not stress anything... Except the smoke detector if you choose an inappropriate insulator

3, use a heated / temperature regulated housing to increase the ambient temperature, need to move the PSU outside the heated zone! possibly the electronics too

4, supplement the heatbed with a silicone heatpad underneath, use a solid state relay and a second power source for the additional heating element
hopefully the hot end will not be too slow.

5, risk using a higher power hot end heater cartridge... this will probably need a better power supply.

6, a combination of the above!

Regards Joan

Re: What mods would make the heat bed and the hot end heat faster?

I lose a lot of time waiting for them to heat to their target temperature before the print can begin. Are there any mods (e.g. bigger power supply) that can be done to significantly speed up their heating?

"I lose a lot of time waiting" - Define a lot of time, 2 or 5 minutes?

A better psu (Same voltage but more Amps) will help, eg: if you heat up bed only it will heat up faster than if you heat both nozzle and bed at same time with current psu, because you can draw more amps just for the bed, but still you need to heat the nozzle and the time will be the same or even higher, so a new psu will help, but a only a little.
Put a bottom isolation to keep temperature traped.
You can't do much more about it, and i don't recommend you change the heatbed to something more powerfull or AC ones.
If you print ABS at 100-115ºc i can understand, but if PLA i don't, it heat up very fast.
If you want to continue printing, edit end gcode script to not disable the heaters, even if you forget to turn then off the printer now have a 30m timer to disable them. If you press the reset button printer will enter in cooldown, so very easy to manage that

Re: What mods would make the heat bed and the hot end heat faster?

Thanks, both of you, for the excellent suggestions!

BTW, I just now noticed that metacollin appears to be using cork, or some such, on the bottom of his heat bed:

With the volcano, this issue has actually diminished in importance, because now the ooze is more likely to break off during the initial priming wipe (as it's supposed to). Prior to the volcano, it more often than not didn't, and so I was compelled to standby during the warmup with needle nose pliers to remove the ooze drool just prior to the print starting. So the warmup, in absolute time, wasn't long, but it's a bit like the watched pot never boils effect. It seems that now I don't need to do that, and I'm more comfortable now just launching a print job remotely using octoprint and checking it later. Almost, but not quite. Getting there though.. That's the dream. Then I won't care much about the warm up time.

Re: What mods would make the heat bed and the hot end heat faster?

I ran some tests on the printer. when using the preheat from the printer on pla the unit pulls over 10 amps. The power supply is rated at 10 amps. You should never pull over the max rated current. This only happens when you are heating the average is between 2 and 6 amps when printing that is fine so the power supply should last for a while but every time you heat you are weaking the power supply. I bought a meanwell power supply 24V 25amps figured this way I will never stress the power supply. When I bought the new power supply I figured more than double the current requirement the power supply will never see over 50% of it's rating. I have had power supplies start on fire and I really like the way my house is without having a fire event and loosing everything. 😮

Re: What mods would make the heat bed and the hot end heat faster?

I ran some tests on the printer. when using the preheat from the printer on pla the unit pulls over 10 amps. The power supply is rated at 10 amps. You should never pull over the max rated current. This only happens when you are heating the average is between 2 and 6 amps when printing that is fine so the power supply should last for a while but every time you heat you are weaking the power supply. I bought a meanwell power supply 24V 25amps figured this way I will never stress the power supply. When I bought the new power supply I figured more than double the current requirement the power supply will never see over 50% of it's rating. I have had power supplies start on fire and I really like the way my house is without having a fire event and loosing everything. 😮

If prusa PSU are well made and use good components (No clones or bad ones) it will have same dangerous as others with more Amp rating, nothing is 100% safe.
For people who want to keep the prusa psu and go safe i recommend heat bed first, wait, heat nozzle, wait and print. This way you never reach the psu limit.

my start gcode:

M115 U3.1.3 ; tell printer latest fw version
M300 S2500 P100; Beep
M201 X1000 Y1000 Z200 E5000 ; sets maximum accelerations, mm/sec^2
M203 X200 Y200 Z12 E120 ; sets maximum feedrates, mm/sec
M204 S1250 T1250 ; sets acceleration (S) and retract acceleration (T)
M205 X10 Y10 Z0.4 E2.5 ; sets the jerk limits, mm/sec
M205 S0 T0 ; sets the minimum extruding and travel feed rate, mm/sec
M83 ; extruder relative mode
M140 S[first_layer_bed_temperature] ; set bed temp
G1 X0 Z100 ; this is a good PINDA heating position
M190 S[first_layer_bed_temperature] ; wait for bed temp
M104 S[first_layer_temperature] ; set extruder temp
M109 S[first_layer_temperature] ; wait for extruder temp
G28 W ; home all without mesh bed level
M860 S35; Wait for pinda temp
G80 ; mesh bed leveling
G1 Y-3.0 F1000.0 ; go outside print area
G92 E0.0
G1 X60.0 E9.0 F1000.0 ; intro line
G1 X100.0 E12.5 F1000.0 ; intro line
G92 E0.0
M221 S{if layer_height<0.075}100{else}95{endif}

Re: What mods would make the heat bed and the hot end heat faster?

I ran some tests on the printer. when using the preheat from the printer on pla the unit pulls over 10 amps. The power supply is rated at 10 amps. You should never pull over the max rated current. This only happens when you are heating the average is between 2 and 6 amps when printing that is fine so the power supply should last for a while but every time you heat you are weaking the power supply. I bought a meanwell power supply 24V 25amps figured this way I will never stress the power supply. When I bought the new power supply I figured more than double the current requirement the power supply will never see over 50% of it's rating. I have had power supplies start on fire and I really like the way my house is without having a fire event and loosing everything. 😮

If prusa PSU are well made and use good components (No clones or bad ones) it will have same dangerous as others with more Amp rating, nothing is 100% safe.
For people who want to keep the prusa psu and go safe i recommend heat bed first, wait, heat nozzle, wait and print. This way you never reach the psu limit.

my start gcode:

M115 U3.1.3 ; tell printer latest fw version
M300 S2500 P100; Beep
M201 X1000 Y1000 Z200 E5000 ; sets maximum accelerations, mm/sec^2
M203 X200 Y200 Z12 E120 ; sets maximum feedrates, mm/sec
M204 S1250 T1250 ; sets acceleration (S) and retract acceleration (T)
M205 X10 Y10 Z0.4 E2.5 ; sets the jerk limits, mm/sec
M205 S0 T0 ; sets the minimum extruding and travel feed rate, mm/sec
M83 ; extruder relative mode
M140 S[first_layer_bed_temperature] ; set bed temp
G1 X0 Z100 ; this is a good PINDA heating position
M190 S[first_layer_bed_temperature] ; wait for bed temp
M104 S[first_layer_temperature] ; set extruder temp
M109 S[first_layer_temperature] ; wait for extruder temp
G28 W ; home all without mesh bed level
M860 S35; Wait for pinda temp
G80 ; mesh bed leveling
G1 Y-3.0 F1000.0 ; go outside print area
G92 E0.0
G1 X60.0 E9.0 F1000.0 ; intro line
G1 X100.0 E12.5 F1000.0 ; intro line
G92 E0.0
M221 S{if layer_height<0.075}100{else}95{endif}

yes that will work I just don't like the thought that if one time I forget and the one time BOOM I have a fire. I just like knowing that I have more than I need but that's just me.

Mark

Re: What mods would make the heat bed and the hot end heat faster?

BTW, I just now noticed that metacollin appears to be using cork, or some such, on the bottom of his heat bed:

my printer. high temp heat reflecting non conductive foil + cork

Also did everything that joan suggested since years ago.
Besides the silicone heater pads, i hate 'em. throw off PID

Re: What mods would make the heat bed and the hot end heat faster?

I ran some tests on the printer. when using the preheat from the printer on pla the unit pulls over 10 amps. The power supply is rated at 10 amps. You should never pull over the max rated current. This only happens when you are heating the average is between 2 and 6 amps when printing that is fine so the power supply should last for a while but every time you heat you are weaking the power supply. I bought a meanwell power supply 24V 25amps figured this way I will never stress the power supply. When I bought the new power supply I figured more than double the current requirement the power supply will never see over 50% of it's rating. I have had power supplies start on fire and I really like the way my house is without having a fire event and loosing everything. 😮

I agree 100% with your overkill philosophy. Overkill is always better than underkill. So, if you're happy with yours, I'd like to blatantly copy what you did. This way I can simultaneously bed level and heat both the HB and HE. Therefore, if you don't mind my asking, which Model Nmber did you get, and where did you purchase it?

OK, I'm guessing it's this: https://www.amazon.com/Mean-Switching-Power-Supply-SE-600-24/dp/B00MEKCM8M

At half the price, though, I suppose this is probably sufficient: https://www.amazon.com/MeanWell-LRS-350-24-Power-Supply-350W/dp/B077B36KPB/ref=sr_1_15?ie=UTF8&qid=1528047777&sr=8-15&keywords=meanwell+24v+power+supply

and toss in one of these:
https://www.amazon.com/URBEST-Module-Switch-Socket-IEC320/dp/B00ME5YAPK/ref=sr_1_19?ie=UTF8&qid=1528047777&sr=8-19&keywords=meanwell+24v+power+supply

Or, get the cheap chinese version of the 600w supply for even less: https://www.aliexpress.com/item/Switching-Power-Supply-DC24V-25A-600W-Ac-Dc-Converter-Transformers-110V-220V-AC-TO-DC-SMPS/32635841591.html?spm=2114.search0104.3.8.70b41f98M3iEah&ws_ab_test=searchweb0_0,searchweb201602_2_10152_5722813_10151_10065_10344_10068_10130_10324_10342_5722613_10547_10325_10343_5722913_10546_10340_10548_10341_10545_10696_10084_10083_5722713_10618_10307_10059_100031_10103_10624_10623_10622_10621_10620_5722513,searchweb201603_1,ppcSwitch_7&algo_expid=90f10423-78ab-46a2-9c26-520d30eeda42-1&algo_pvid=90f10423-78ab-46a2-9c26-520d30eeda42&priceBeautifyAB=0

And the winner is.... whatever fits the one Prusa I3 MK3 PSU case on thingiverse:
https://www.thingiverse.com/thing:2812350
i.e. Mean Well NES-350-24

From reading this thread ( https://shop.prusa3d.com/forum/hardware-firmware-and-software-help-f64/power-supply-failure-t13443.html ), it sounds as though the firmware uses a less than 100% duty cycle so as to avoid overloading the PSU. Therefore, from a speed point of view, just upgrading to a better PSU is not enough. For better speed, the firmware will need be changed to use a 100% duty cycle (provided, of course, that the selected PSU can handle it, obviously) to take advantage of the superior PSU.

Re: What mods would make the heat bed and the hot end heat faster?

I lose a lot of time waiting for them to heat to their target temperature before the print can begin. Are there any mods (e.g. bigger power supply) that can be done to significantly speed up their heating?

"I lose a lot of time waiting" - Define a lot of time, 2 or 5 minutes?

I measured the warm-up time for the HE and HB.

Hot-End (30w volcano): 26C to 230C took 3 minutes 24 seconds

Heated Bed: 25C to 60C took One minute and 31 seconds.

Everyone thinks the Hot-End is faster--probably because the rate of heating is faster--but it isn't so.

These are with the stock Prusa power supply.

[Edit: Heating both HE and HB simultaneously, it takes 3 minutes 24 seconds to finish heating up, with the HB finishing first. So, it appears the firmware doesn't throttle the heating process after all, or at least not how I imagined it would. That's good news. Again, these measurements are for the stock Prusa power supply.]

[Edit2: I did have this bed leveling failure this morning, so I guess I'll need to look into the PINDA temperature issue sooner rather than later:

Re: What mods would make the heat bed and the hot end heat faster?

Try going to 110 C for the bed. That's definitely slower than the hotend getting to 255 C. I insulated the back side with cork and stuck the whole printer in a heated enclosure. It's faster, but still slower than my impatience. I kind of want to design my own flavor of the control board that runs off of mains for heating elements.

Re: What mods would make the heat bed and the hot end heat faster?

I ran some tests on the printer. when using the preheat from the printer on pla the unit pulls over 10 amps. The power supply is rated at 10 amps. You should never pull over the max rated current. This only happens when you are heating the average is between 2 and 6 amps when printing that is fine so the power supply should last for a while but every time you heat you are weaking the power supply. I bought a meanwell power supply 24V 25amps figured this way I will never stress the power supply. When I bought the new power supply I figured more than double the current requirement the power supply will never see over 50% of it's rating. I have had power supplies start on fire and I really like the way my house is without having a fire event and loosing everything. 😮

I agree 100% with your overkill philosophy. Overkill is always better than underkill. So, if you're happy with yours, I'd like to blatantly copy what you did. This way I can simultaneously bed level and heat both the HB and HE. Therefore, if you don't mind my asking, which Model Nmber did you get, and where did you purchase it?

OK, I'm guessing it's this: https://www.amazon.com/Mean-Switching-Power-Supply-SE-600-24/dp/B00MEKCM8M

At half the price, though, I suppose this is probably sufficient: https://www.amazon.com/MeanWell-LRS-350-24-Power-Supply-350W/dp/B077B36KPB/ref=sr_1_15?ie=UTF8&qid=1528047777&sr=8-15&keywords=meanwell+24v+power+supply

and toss in one of these:
https://www.amazon.com/URBEST-Module-Switch-Socket-IEC320/dp/B00ME5YAPK/ref=sr_1_19?ie=UTF8&qid=1528047777&sr=8-19&keywords=meanwell+24v+power+supply

Or, get the cheap chinese version of the 600w supply for even less: https://www.aliexpress.com/item/Switching-Power-Supply-DC24V-25A-600W-Ac-Dc-Converter-Transformers-110V-220V-AC-TO-DC-SMPS/32635841591.html?spm=2114.search0104.3.8.70b41f98M3iEah&ws_ab_test=searchweb0_0,searchweb201602_2_10152_5722813_10151_10065_10344_10068_10130_10324_10342_5722613_10547_10325_10343_5722913_10546_10340_10548_10341_10545_10696_10084_10083_5722713_10618_10307_10059_100031_10103_10624_10623_10622_10621_10620_5722513,searchweb201603_1,ppcSwitch_7&algo_expid=90f10423-78ab-46a2-9c26-520d30eeda42-1&algo_pvid=90f10423-78ab-46a2-9c26-520d30eeda42&priceBeautifyAB=0

And the winner is.... whatever fits the one Prusa I3 MK3 PSU case on thingiverse:
https://www.thingiverse.com/thing:2812350
i.e. Mean Well NES-350-24

From reading this thread ( https://shop.prusa3d.com/forum/hardware-firmware-and-software-help-f64/power-supply-failure-t13443.html ), it sounds as though the firmware uses a less than 100% duty cycle so as to avoid overloading the PSU. Therefore, from a speed point of view, just upgrading to a better PSU is not enough. For better speed, the firmware will need be changed to use a 100% duty cycle (provided, of course, that the selected PSU can handle it, obviously) to take advantage of the superior PSU.

True on the duty cycle but I am just going from my original tests when I select preheat from the printer and my meter reads 10.8 amps and the power supply is rated only at 10 amps. (I know your going to ask how did I get over 10 amps well I have a adjustable power supply that does 20 amps upto 30 volts. ) I perfer to stay with power supplies that I know. I use meanwell for my Christmas display and have never had one fail.

Mark

Re: What mods would make the heat bed and the hot end heat faster?

2, insulate the lower side of the heatbed this needs to be high temperature insulation, cork may do... i suspect the hot end already heats up faster than the heatbed, so rather than delay the hotend heating to prevent bed levelling blobs, consider using the heater as it is, this will not stress anything... Except the smoke detector if you choose an inappropriate insulator

How do you afix the cork to the bottom of the heat bed?

Re: What mods would make the heat bed and the hot end heat faster?

2, insulate the lower side of the heatbed this needs to be high temperature insulation, cork may do... i suspect the hot end already heats up faster than the heatbed, so rather than delay the hotend heating to prevent bed levelling blobs, consider using the heater as it is, this will not stress anything... Except the smoke detector if you choose an inappropriate insulator

How do you afix the cork to the bottom of the heat bed?

I used wood glue with the cotton mat, don't know if works with cork

Re: What mods would make the heat bed and the hot end heat faster?

PVA wood glue, should do. ( you can use it for print bed treatment often used on Glass with ABS)

or 3m double sided tape like they use for PEI

Gorrilla Glue would do a permanent job... but it's messy and almost impossible to get off!

regards Joan

Re: What mods would make the heat bed and the hot end heat faster?

I wonder if it would be possible to custom3D print some insulation using PETG filament--perhaps some kind of honeycomb pattern with lots of trapped air and get an exact fit.

Re: What mods would make the heat bed and the hot end heat faster?

PETG would be no good if you plan to print ABS or PC the bed temperature would be a bit to hot for the PETG

Regards,
Martin

Re: What mods would make the heat bed and the hot end heat faster?

The easiest and fast thing you can do is apply reflective type that come ready with the adhesive, one or two layers will do

Re: What mods would make the heat bed and the hot end heat faster?

Found this mod for raising the heated bed temperature faster:
Basically, it raises the voltage on the output from the power supply.

I wonder if using step-up voltage converter on the voltage going to the heated bed might not also work to raise the voltage even further?

Re: What mods would make the heat bed and the hot end heat faster?

Found this mod for raising the heated bed temperature faster:
Basically, it raises the voltage on the output from the power supply.

I wonder if using step-up voltage converter on the voltage going to the heated bed might not also work to raise the voltage even further?

I don't recommend this, that video is a fail and a danger. If you do so you can burn your motherboard, the boards by design always have a top limit voltage that can hold, if you pass that limit the board will burn and pop and you need a replacement. I don't know the max supported voltage but you have to take in account other things like ripple and spikes. Also other boards can have tight limits and people who follow that may become in a loss. +1V may not damage but +2V or +3V can do more bad than good.
Hotend, bed, board is 24V, supply it with 24V and don't mess with that.
If you want to speed up bed time in a proper way you can apply a silicone heat mat, it will heatup 3x faster but you need a better power supply than the stock one. Not worth IMO.

Example: https://www.aliexpress.com/item/150x150mm-24v-100w-Silicon-Heater-3D-Printer-Heater-Bed-with-3M-Adhesive-and-100K-Thermistor/1000001484408.html
You will have to hole that thing because of the screws, and that can damage the mat