Take a look at the
E3D. I have one on one of my 3D printers, and have had a couple different versions of Printrbot's derivativ
e. One of Printrbot's had a marginal heater, the others have had melt rates in the 20s (as in cubic mm per second).
There's a large number of copies from the usual sources, of varying quality. I believe you can find blueprint
s online, if not you should be able to copy it from pictures, etc. The clones often have a rough internal finish that makes them more prone to jamming, so if you roll your own then do a good job of polishing the innards. I'm not a big fan of PTFE liners as that'll limit your max temp and ability to use some of the higher temp filiments
. I've polished mine with yarn and buffing compound, but it's time consuming and boring...
If you do go the roll your own route (of course, that'll end up costing you at least 3 times as much as buying one) then thread the heater block to take standard E3D nozzles, M6x1.0 iirc. I've made my own in the past (my first extruder had a 1/4-20 male thread so brass acorn nuts made good blanks) but they're cheap and easy to find. Heat breaks (the section between the fins and the heat block) are critical, you want the temperatu
re to drop as quick as possible to avoid early melting and jamming, as is how fast you shed heat in the heatsink area. Some use fans to help, the cheap ones are whiny and annoying so don't get your fan out of the bargain bin.
Kirk
