Extruder using temperature controlled soldering iron element

I just did a quick search to see if this idea has been covered. I had the thought of using the above, perhaps inserted into an alloy billet melting chamber as I am still thinking over the idea. The thought being these soldering stations are quite cheap, and intended for extended use and have pretty good temperature control, and a melting chamber should have mass to even out heat loss. Perhaps the only downside is the large heat element at 50w.


Joules

Yes I tried one. It did not work because it has a gradual thermal gradient along the length the barrel. You can see the results here: [hydraraptor.blogspot.com]

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[www.hydraraptor.blogspot.com]

Thanks
onto the next plan Stan

Has anyone tried using a peltier effect heat pump to purposefully create a fast thermal gradient along a piece of thin walled stainless steel ?

I'm thinking of snug fit aluminium plates sandwiching a peltier heat pump , and with fingers drilled for tight fit over thin walled stainless steel tubing. So, the heat pump is actively enforcing the differential, and after the power is regulated sufficiently to create the hot side extrusion target temp, a high proportion of the leaked heat is redirected right back to the hot side via the thermal conduction path to the cold side.

Only problems... the ones I know of, are expensive, and can't withstand that high a temperature anyway. Wax feed stock would run OK though, (for lost wax casting prototypes)

Peltier's don't have to be expensive. I got a pair of 320W peltiers for $40. Ebay helps.

Those 320W Peltiers would probably be about right for this application - I was looking at some datasheets, and it looks like the Q drops off by a factor of 10 once you get up to a delta-T of 60 Deg C. I haven't seen any that can hit 240 C yet, but there might be a few.

Annirak, do you have a datasheet for those Peltiers, or a part number? I'd be interested in checking them out.

My current extruder runs at a delta T of 160 deg C across the thermal break without a heatsink, so there's a ways to go yet. It's hard to beat the Q of a cheap CPU heat sink when you're running well above ambient though. Most refrigeration cycles get less efficient as the delta T increases, whereas a simple heatsink dumps more heat the hotter it gets. Watercooling works the same way, up until you boil off your coolant.

I made the same mistake on a hybrid locomotive once - we tried to keep the power transistors below ambient temperatures using a specialized chiller, thinking they'd last longer that way. It worked well as long as the locomotive wasn't working too hard, but when we started dumping a couple thousand horsepower through the IGBT's on a hot day, the cooling system would heat up, and at the same time loose it's ability to reject heat. In the end, plain old watercooling was simpler, better, cheaper and way more reliable. It sure beat trying to kick start the chiller thermal cutout on top of a moving locomotive!

Wade

Unfortunately, they were ebay specials. They came without datasheets. All I know is that they're rated to 16V, 320W, 60C delta.

Ah, just have to try it and see then! I'll wait till I can find one that handles the temperatures I'm interested in though.

Edited 1 time(s). Last edit at 01/19/2009 03:16PM by Wade Bortz.

They do sound too expensive.
Isolate the supplies though, and you can series up the heat differentials to gain a far bigger delta.

i made some tests making a extruder using iron powder with electromagnetic handling of the powder and electromagnetic heating to "white" , all encased on ceramic cone.
If this proyect works well i post it.

How can one fit a peltier square onto extruder m6 thread? does it works to drill a hole in the peltier module, i meant wont it be damaged?