Extruder heat lagging

I've got an issue where the extruders actually heating up is severely lagging behind the input for heat upon warm up. I don't have any issues once the machine is up to temp and running.

I've got the standard Flashforge Creator dual head and I just upgraded the firmware last night to Sailfish v7.5 via Replicator G which had a note that it addressed extruder lag. I've also only operated via USB so far.

If I use the control panel, I do see the commands for temperature and the bed heats up, but the extruders just have a massive delay until one starts heating up, then the other gets going. I also seemed to notice, maybe a coincidence that as soon as the fan's turn on, the last extruder to be lagging starts going.

Is there a deeper diagnostic tool I can use to try to sort out where the problem is, like seeing if the board is actually making the command for the heaters to turn on?

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Originally Posted by indy3der

I've got an issue where the extruders actually heating up is severely lagging behind the input for heat upon warm up. I don't have any issues once the machine is up to temp and running.

I've got the standard Flashforge Creator dual head and I just upgraded the firmware last night to Sailfish v7.5 via Replicator G which had a note that it addressed extruder lag. I've also only operated via USB so far.

If I use the control panel, I do see the commands for temperature and the bed heats up, but the extruders just have a massive delay until one starts heating up, then the other gets going. I also seemed to notice, maybe a coincidence that as soon as the fan's turn on, the last extruder to be lagging starts going.

Is there a deeper diagnostic tool I can use to try to sort out where the problem is, like seeing if the board is actually making the command for the heaters to turn on?

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This is not a delay, it's the firmware - so unless you want to physically write new code, that's the way it is. Your Hotbed heats up until it gets to 1-2 degrees below set temp, then the nozzles start up. Exactly why, I don't know... it could simply be down to processing power - they are just an arduino mega really.

Yes, it's annoying waiting for the nozzles so you know what you do?

That annoying few seconds when it does its homing axes before a print (the one that moves it to the corner while it compiles the job) this stops the preheat and you lose time and then you have to wait for it to heat up again)

Set your preheats a few degrees higher, so if your bed needs to be 110, set the preheat to 112c, and if the nozzles are 230c for example, set them to 234c. So, when the homing axes crap happens before a print, the small cooldown that it does to .. by the time the job verifies and prints, the cooldown is actually at the printing temp, or thereabouts so you have less waiting.

Thanks Geoff!

I'm happier to know that everything is working as it is designed to work.

I wonder if it is a power consumption thing in only allowing so much current to go into heating at a time. I'd rather have that than a melted power supply.

I'll take your advice and overshoot on the preheat.

Possibly not such a bad thing as it allows the HBP to heat-soak out to the edges for longer.

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Originally Posted by Billzilla

Possibly not such a bad thing as it allows the HBP to heat-soak out to the edges for longer.

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Yeah, it could be Bill. I find that the hotbed really sticks well when I let it sit for a minute at high heat. If I try and print the second it hits 110c its not as adhesive.

I assume the plate is not actually 110c when it says it is, the sensor and the part of the bed above the sensor is - BUT not the rest of the plate. I have found lately over heating the bed on pre-heat and then printing 2 degrees lower is a GREAT improvement.

Set the bed to 112c for preheat, and 110c for printing - works like a dream :)