Since first cracking the whole printing reliably straight to glass problem, I have gotten to the point where the prints are almost sticking too well. They often can be extremely stubborn to remove, and I usually have to wait for the heated build platform to cool considerably (~60°c) before being able to remove a print.

This means loads of time waiting around for the heated build platform to reach the target temperature. This can be a huge pain if I am printing large batches of things. In extreme cases, it can take up to 15 minutes after a print has finished before my printer is ready to roll again.

So one trick, is to turn the heated build platform (HBP) off before the print has actually finished. I usually do this about 2 to 3 minutes before a print is due to finish. The bond between the PLA and the glass is still extremely strong while the glass is cooling and the print finishing. That way, when the print has finished, it is just a gentle, sharp tap with a hammer on the end of a screwdriver to get it off.

But to start the next print, I was still waiting ages for the platform to heat back up again. That was until I stumbled upon something so simple I was embarrassed I hadn’t thought of it earlier.

Poor Rayne Lang from over on the MakerGear forums must live somewhere very cold, he was having trouble getting his HBP up to the target temperature until…

I have had success getting the bed up to 110 if i put towel onto to insulate the top of the bed…

If my printer had some sort of funky tea cosy blankie for the heated build platform, it should heat up faster! Unfortunately, I suck at knitting. So I cobbled together my ‘HBP cosy’ out of some cardboard and my trusty hot glue gun.

image

So did it make much difference? To test, I fired up the trusty pronterface and measured the current resting temperature of the HBP, 24.3°C (the local weather bureau was reporting 25°C). I warmed the platform a little to 27.0°C to try and ensure I had a common starting temperature for my with and without cosy tests. Then rammed the target temperature up to 88°C and measured how long it took to get there.

image

In a total time of 14 minutes 10 seconds.

Alright, time to wait for the heated build platform to cool all the way down and then bust out my cardboard HBP cosy and start again. The starting temperature this time around was 0.1°C warmer than the without cosy test, and again I rammed up the target temperature again to 88°C and started timing.

image

About halfway through the ‘with cosy’ run, my laptop crashed. The heated build platform was still warming for most of the outage (as the indicator LEDs on my printer were still going) But I missed a couple of minutes of readings while I was trying to get my computer reloaded and connected to the printer again. Despite all that, it heated up in 12 minutes and 23 seconds.

image

A pretty respectable time reduction, my HBP cosy speed up the warm times by over 10% (probably more if I didn’t have that dip due to the laptop crash). Not as awesome as I was hoping, I clearly need some of that knitted tea cosy goodness to increase speeds further. Now if only my search “heated build platform cosy” on Etsy returned some results…