RepRap Champion Metal J-Head V6 Hot End for RepRap 3D Printer 1.75mm Filament Direct Feed Extruder 0.4mm Nozzle

I still can't say enough great things about this pen & 3D Cam. I've been using this Extruder for a month now, sometimes hours a a time, and it is still going strong. I see there are some one star reviews that look very suspicious- don't believe these reviews!! 3D Cam's customer service & Gary really care about their customer's satisfaction with this pen and care about having a quality product. I think these bad reviews are from jealous competition. I have used this pen a LOT in my art classes and I highly recommend it to my students and friends. ^_^I ordered this Extruder to replace a defective Extruder from another manufacturer that stopped working after 30 min. of use. I have to say, I am much, much happier with this Extruder and having the option to change temperatures from PLA to ABS is awesome! The pen still works well after many uses and I've used all the filament that came with it. I am an owner of a full-sized 3d printer, so I have many spools of filament on hand. I tried out several colors that I had and they all worked great. It is a little awkward to have the loops of plastic swinging around as you try to use the pen, but it's not a big deal.This pen has a nice shape and isn't too bulky to hold for adults or kids. It does have a learning curve, but think of drawing with cake icing when using the pen. The further away from the surface will give you more uncontrolled "squiggles", whereas the closer the tip is to the surface, it gives you a more controlled line. Give the plastic a second or two to set before moving around, otherwise it will roll on you. But, this can also work to your advantage if you want to smooth out a rough spot- while the plastic still warm, you can use a silicone spatula or tool to push it down. (Don't use your fingers, it is HOT plastic!) The plastic is hard and sturdy if you make enough layers/support. We've made some neat rings to wear as well as little stacking boxes.I am an art teacher and have let my students use this pen. Their ages ranged from 10 to 17 and they all enjoyed it and were able to make fun shapes and 3d objects with it. We use it with tracing paper over magazine/coloring book images and it doesn't burn or stick. I would love to have more of these for my class, so hopefully they will come down in price due to popularity. This is much safer for a kid to use than a hot glue gun, (even the low temp ones) just stress to them not to touch the tip of the pen. The plastic is quite warm when it comes out, but it cools much quicker than hot glue. There can also be a burnt plastic smell at times if the plastic gobs up on the tip, so have a paper towel handy to wipe off the tip if this happens.

haven't used it as yet but will update if anything arises with it s use. Did not come with the tube and fitting but that is probably why it is priced like it is. If you look around I'm sure you can find one complete for the same price point.I wouldn't say "I don't like it " as the 2 star designates but below is a response I wanted to send back to the seller:Just a note for your information. I finally got around to installing on my unit [Metal J-Head V6 Hot End for RepRap 3D Printer 1.75mm ] and much to my disappointment, it did not work. It returned a "MAX_TEMP_ERROR" and would go no further. With further examination it read "0 Ohms resisance" across the thermister resulting in the error code. It looks as if the thermocouple was shorted out causing the problem. Your supplier should excersise more caution while installing the theremocouple and avoid the problem.

It's not the best, but it works for an inexpensive hotend. It jams often but when it does you can easily enough take off the nozzle and heat it up enough to get the clog out. The fan is a nice addition to prevent heat-creep. All in all, you get a usable hotend that works and easily maintainable.

This hot end is decent for the money but doesn't come without it's fair share of problems.My big issue is that there is no PTFE tubing in the hot end so it will constantly clog up resulting in failed prints.It has taken me several days of trial and error resulting in quite a few failed prints to finally realize that the missing PTFE tube was my problem. It works great for a short print but once you start running it for longer than 30 minutes it will clog up and filament will stop being extruded.

The good:very inexpensivegeneric tips fit great and seem to work dandy. (and are inexpensive!)Things to watch out for:This is an active-cooling hot end. Which means it relies on that little fan running _all_the_time_ ... if it doesn't, heat creeps up into the heatsink (finned area) and begins to melt the filament there...which then solidifies ... and doesn't want to melt subsequently. (even if you *remove* said active cooling and run the temp up to 230 degrees C. I tried.) In this case, the only solution I found was to disassemble the damn thing and drill out the blockage.The solution was to wire up the heat-sink-cooling-fan to run all the time. In my case, I just used an old 12v wall wart and left it plugged in until I was absolutely sure the hot end had cooled down.Without insulation of some sort, the heater block seems to cool quicker than the heat element can keep up with ~ especially on longer prints. Simple fix: wrap the heater block in either ceramic insulation or kaptan tape. (or both)Without the proper order-of-assembly, plastic will always wind up leaking out of the top of the heater block regardless of how much teflon tape you wrap the threads with. After much trial and error, I finally hit upon a technique that's worked. You will need 1" kaptan tape (below) and a small amount of ceramic insulation**.disassemble your hot-end ~ remove the heatsink section and nozzle from the heater block. Remove the thermistor and heating element.wrap the heater block with 3 layers of kaptan tape the long ways round. Then wrap 3 layers short ways round. This will leave you with 6 layers of kaptan tape above and below, with 3 on either side. This will help the hot end *stay* hot.Using a sharp hobby knife/box knife, carefully cut out around the holes for the nozzle heater block, thermistor screw, and thermistor. I just cut squares vs. trying to get all fancy and do a circle. Worked fine.This part might be overkill, but I did it to help further block radiant energy going up to the heatsink area. Cut a square of ceramic insulation about 1" square. Use a hole-punch to put a hole in it.put the ceramic insulation on the heatsink, with the hole going through the bit of the heatsink that screws into the heater block.screw the heatsink into the heater block (almost) as far as it'll goscrew the nozzle onto the heater block and (this is the important bit!) make sure it bumps into the end of the screwed-in heatsink while there's still a gap between the nozzle and the heater block. See the image for a crude drawing. Then tighten down the nozzle while holding the heater block with a crescent wrench. If you do it in this order, the final tightening will be with two things you can get wrenches on.If you *don't* assemble it in this order, you won't be able to get the nozzle's connection to the filament tube tight enough. (eg, you'll tighten the nozzle first, then try and get the heat-sink-tube-end tight ... which you can't do because it's a circle...and then it'll work fine at first ... but then you'll start noticing strange blobs on your prints .... eventually discovering plastic was leaking out of the *top* of the heater block ... and you'll have this happen over and over despite how tight you reef on the heatsink-side to tighten the tube ... )*I used this: http://www.amazon.com/Mil-Kapton-Tape-Polyimide-yds/dp/B006ZFNB2I/** I didn't want to wait, so I purchased something like this from a local auto parts store: : http://www.amazon.com/Versachem-90100-Exhaust-Tail-Repair/dp/B002N5PQOA/ This one says it has some ceramic insulation with it, but I don't have any idea how much. [3D CAM] Metal J-Head V6 Hot End for RepRap 3D Printer 1.75mm Filament Direct Feed Extruder 0.4mm Nozzle