Water cooled hot end-thoughts?

Hello everyone. So today, I stumbled across this: [www.indiegogo.com] and really, I was curious what all of you thought. My question is really why it's necessary. If the water cooling could make the temps rise to like 500c, I'd like it, but it can only get up to 350c, yet the e3d v6, with a couple changed parts, can get up to 400c. Does it just mean it lasts longer or what? Just thought I'd start a conversation about it.

The only value I can see in the extra complications is if you are going to print inside an oven and the ambient air temperature will be too high to keep the cold end of hot-end cool.

Older Stratasys FDM printers print inside a 70C oven and have flexible hoses attached to the extruder to blow cool air from outside the oven over the extruder.

I watched a review on youtube and the person didn't give it a good rating because there's no interchangeable nozzle also the nozzle has a concave to it Google for the video review

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They are solving a non-existent problem. What shortcomings of existing extruders are they attempting to fix? Do they find the current generation of extruders to be unreliable? Are extruders limited by cooling?

Watercooling is problematic because flexing the hose continuously for months or years of use is not a great idea. Do you really want to have to rip up the loop as part of preventative maintenance?

If you want a heated chamber there are far more elegant solutions such as keeping the hotend at ambient temperature or just blowing cold air on it. Stratasys has a lot of good ideas here.

the independant youtube video review is here [www.youtube.com]

He didnt like it one bit.

Edited 1 time(s). Last edit at 05/13/2015 11:37PM by Dust.

E3d are doing a water cooled hotend and someone has made one reprap style

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Check my rubbish blog for my prusa i3

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[3dimetech.blogspot.co.uk]

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chris33
E3d are doing a water cooled hotend

The difference between this and the Kracken is that the Kracken has 4 hot ends in a very small space. 4x the heat in confined area without a easy way to direct airflow across all heat sinks creates a unique problem, one which water cooling addresses. For a single extruder/hot end on a normal printer, I don't think those same problems exist and therefor probably don't need solved.

The main reason why the prints out of an e3d hotend come out so good are because of its very short transition zone, meaning the zone inbetween solid and molten polymer is very short.
Less jamming issues and less blobby prints are the result of this short transition zone achieved by the thin walled steel "heatbreak" followed by the huge air-cooled aluminium cooler e3d uses.
Using water cooling this effect can be maximized, but I am not sure if it really needs to be maximized since e3d already does a pretty good job there, also with their materials selection
(steel is a much worse thermal conductor than aluminium, thats why the e3d heatbreak is made of steel). If the effect could be maximized, I would use a copper heatsink instead of an aluminium one
on the e3d to get rid of heat above this transition zone, hence making the zone smaller, which is something I would do first as an engineer before swithing to watercooled overkill.
(apart from copper price issues, but then again, how expensive is the whole wc equipment?)

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Yellobello
(steel is a much worse thermal conductor than aluminium, thats why the e3d heatbreak is made of steel).

They are made of stainless steel, not steel. Stainless has about 1/3-1/4 the thermal conductivity of high and low carbon steel.

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If the effect could be maximized, I would use a copper heatsink instead of an aluminium one

Copper is much harder to machine than aluminum and it's not necessary. Plus as you pointed out would also be more expensive due to metal prices. The existing setup of aluminum heat sink and fan more than adequately cool the hot end. If you were pushing the envelope and needed the maximum amount of thermal conductivity to keep things cool (e.g. a CPU heat sink) then copper may be a consideration. But with aluminum being cheaper, easier to work with, and good enough to keep things cool with the fan, it's a no brainer which to use.

Thanks for all the replies everyone! I'm really glad for that review as well.

Also copper is very heavy compared to aluminium.

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