Some thoughts on the HOT end.

A few thoughts on the heated end.

larger thermal mass is better - just like a flywheel - the thermal mass holds the energy ( heat ) better - so when the heat is transferred rapidly to the filament it doesn't suck ALL the heat out - so the heater barrel can maintain the proper heat without dips...

a heat sink is a BAD thing....

on the heater barrel, but not on the fillament channel

i.e. it's good if the inlet is coolled, but it shouldn't be connected to a highly conductive (thermally) part...

the heater barrel should not have to waste ANY energy heating what shouldn't be heated...

(the boards are taxed enough - so improving the efficiency by keeping the heating where it NEEDS to be is better, and not heating anything else (the room, the cold channel etc) is CRITICAL!

you should be able to heat the heater barrel with a minimum of energy and insulate it to keep it hot as well.

HOWEVER - because support material can now be used in the same material, there needs to be a way to COOL the barrel quickly as well... in order to speed up printing.

(cold support layers don't stick to cold object layers

so

the interface/support material is best laid down at about 20-30 deg colder than the object material, and the first layers (touching the support layers) should be about half way between the cold support and hot object layers.

it makes support removal OODLES better

EDIT:

Thanks for the comment, you're right - water cooling is something I was thinking about - but of course this is a DIY type thing, so water + electricity + human error = BAD SITUATION! :D hehe... so I was thinking it'd be better to move some air in there - through some copper piping or something like that.

I'm travelling right now with the bot - so I don't have access to all my tools - but plan on experimenting virtually in CAD.

I have a hot end that is working REALLY well - save the long heated channel - which I will be shortening eventually when I can make a coolable thermal block (instead of a long steel hollow tube). hmmm.... liquid cooled - I wonder if I could use some pieces from a liquid cooling system used for cooling overclocked PC hardware - certainly those are designed for liquid SAFETY! - maybe liquid cooling of the hot end IS possible!

Again, thanks for reading - I'll try and post more often!