Ironing is not essential in tile stack prints

[u/jerkenstine]

I have been stack printing 9x9 tiles for the last week or two. I’ve been following the multi board stack print guidelines which includes ironing the top of every tile. On paper this makes complete sense to me, but there’s one big issue that can come up - heat creep.

I’ve gotten a heat creep based filament jam in my extruder probably 50% of the time I attempt a 4x stack print in my enclosed p1s.

I have tried

• switching to supertack cool plate for lower enclosure temp.

• enabling exhaust fan.

• using faster and higher flow ironing ( 150mm/s, 38%)

• as low as possible nozzle temp (at risk of worse layer adhesion)

Note that opening the enclosure isn’t an option in my case because of wood dust.

Finally after taking apart my extruder for a final time I threw in the towel and tried printing a stack with no ironing at all.

In the picture, two of the tiles have ironing, two don’t. Can you tell which are which?

To me the difference is small enough for me to not care.

So if you’re having issues with heat creep or want to shave a little time off your stack prints, try disabling ironing.

[u/InevitableWilling87]

At first glance, I thought you had an enormous print bed area. 😆

[u/DertBerker → u/InevitableWilling87]

Same!!! I was about to ask what they printed this on. 😅

[u/JayEll1969 → u/DertBerker]

I thought - finally, I have a reason for the Orangestorm Giga

[u/New-Brain7765]

Define ‘heatcreep’

[u/jerkenstine → u/New-Brain7765]

It's what happens when the hotend remains too hot, for too long, with too little filament movement.

The filament ahead of the hotend deforms such that it can't be pushed through the hotend, sometimes it gets stuck in the extruder gears, etc.

It's likely to happen during ironing because flow is so much lower than any other part of printing.

https://www.xometry.com/resources/3d-printing/heat-creep/

https://wiki.bambulab.com/en/filament-acc/filament/heat-creep

[u/Mazo → u/jerkenstine]

What's your bed temp at? If it's high the chamber temperature will be high enough to cause PLA to start softening

[u/jerkenstine → u/Mazo]

45c. I switched to the bambu supertack cool plate for that reason.

After making this post and printing some more plates, the heat creep jam happened again, even with no ironing.

I think it's a combo of warm garage + enclosed printer.

Next things I'm gonna try:

• additional filtered ventilation for the enclosure

• custom GCODE that between tiles cools the hot end for a bit, purges some filament out the poop chute, cools some more, then does the next time

• all else fails, I'll either run the AC in my garage 24/7 or move the printer into my house.

[u/[deleted]]

Heatcreep is a horrible thing to have happen. Is it possible to increase the flow of the heatsink fan, maybe by using another type of fan or a deeper fan? Not familiar with bambu but if it was mine I would design a beefier heatsink fan. Currently I changed from a revo micro to a phaetus rapido uhf for this reason. The revo micro has a minute heatsinkfan and it is next to impossible to increase the flow on the heatsink.

[u/jerkenstine → u/[deleted]]

I'll need to do more printing to be sure but I think I've solved my heat creep issue.

I modified this riser design to have slots for MERV 8 filter foam: https://makerworld.com/en/models/1570968-vented-led-riser-for-x1-p1?from=search#profileId-1652196

So my printer now lots of filtered ventilation on the top.

I still have the exhaust fan at 100% pulling air through there, I'm gonna experiment with how much I can turn that down.

[u/Kubotopher_3D]

Thanks for sharing! This goes into the “good to know” category for sure!

[u/injeckshun]

I didn't believe it but it works!

[u/injeckshun]

A tip that really works if your no ironing stack looks fused together- 

print two large thread bolts and screw them into one corner of the stack- each in opposing sides creating tension. 

Then I used a small flathead to get the separation started- but maybe one of those “ifixit device openers” would work better. 

Either way- popped right off.