mandag 9. mai 2011

Mendel-parts.com - v6 hot end first impressions

I've been using the v6 hot end from mendel-parts.com for a couple of days now, and although that is not enough time to do a complete review, I would like to share a few things I've learned.

  • It's working beautifully! I always thought the hardware was to blame for my sub-par print quality, but with a proper hot end and skeinforge 41, I was able to spot the hardware problems. A new belt on the x-axis and metal gears on x and y axis did the trick.
  • I (and I'm not alone) needed to glue the PTFE tube/liner to the brass part to avoid it forming a blob which clogged up the whole thing. I did it by roughing up the surface of the PTFE and the inside of the heater barrel, and put on a very small amount of thermal glue. Take care not to clog the barrel! It seems to be working out nicely. Here's a picture after the first failed attempt at attaching it to a wades. The mounting bracket failed, and both the PTFE and PEEK pushed out of the barrel, resulting in all sorts of funky cleanups.

  • I don't like to glue the thermistor in place. Both because it would be impossible to remove, and because the thermistor I have from ultimachine is too big to fit. I could of course use the thermistor supplied with the hot end, but then I would have to change the temperature table which is not readly available. Anyway, I went with my decision of attaching the thermistor to a ring terminal and replace the copper ring with it. It worked out fine, but the temperature was WAY off. Because I use to weak springs on Adrians extruder, I had to increase the temperature to 205 degrees to get proper extrusion. After a while it clogged up and I found this inside the barrel. (Be warned, it's not pretty).
    •  I now extrude at 180-185 and it works beautifully, I think I could go lower still.
    • EDIT: I have a theory the gunk was bits of PLA the extruder grinded off the filament, and not necessarily the temperature.
  • I didn't damage anything apart from breaking off the filament guide off "driven-holder.stl". Here I'm printing a new "idler-holder.stl" to have a spare.
  • To sum it up:
    • The mendel-parts v6 hot end works great!
    • Glue the PTFE tube to the barrel (carefully).
    • Use strong springs on Adrians extruder.
    • Test your temperatures with natural PLA to check for discolouring.
    • Skeinforge 41 with volumetric 5d is incredible! (Don't waste your time slicing with the old repsnapper windows build that's available).
    • When you turn off the machine, leave the plastic inside. I had no problems extruding straight away when heating it up again. If you pull it out it will most likely form a plug.
Update 01.02.2012: I've used the v6 hot end for a long time, and it's decent. Though because the melt chamber is so large it drools a lot, and the filament lingers a long time when changing colours. The Arcol v3 and J-heads (and others?) has no such melt chamber, only a straight path to the nozzle, which I find is a better solution. This is written only for completeness sake, as the v6 is no longer sold. Though the v9 looks similar, I have not seen it in person and don't know how it performs.

Well.. I'm off to figure out why skeinforge 41 sometimes decides to home during a print. It's no problem when it homes towards the endstop, then it just goes back to printing. The problem is when it anti-homes away from the endstop, trying to push the x carriage or the bed off the bars. I could attach endstops there probably, but that's just circumventing the problem.

Edit: Oh, and I made a funny Minecraft Creeper Keychain, check it out.
 -Nudel