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So I know some of the eMaker loyalists have had some hard times with their bowden tube on their extruders, so I've been playing around with possible replacements. Honestly, I was having quite the time finding 3mm OD and 2mm ID tube even remotely related to teflon. I ended up going down the list of teflon related materials looking for 1/8" tubing thinking .125" OD is only slightly bigger than 3mm and maybe the larger diameter would make for a tighter fit in the pneumatic fittings.

The last thing that I've tried that seems to be working so far (now that I've got some hot-end issues worked out) is .125" OD, .093" (2.36mm) ID, FEP tubing from McMaster P/N 9369T24, http://www.mcmaster.com/#9369t24, for about 2.27 USD a foot. Its wall thickness is a little on the thin side but it is flexible you just have to be careful about kinking the tube when cramming it into the pneumatic fitting. FEP, http://en.wikipedia.org/wiki/Fluorinated_ethylene_propylene, is very similar to PTFE, PFA and other teflons being almost as slick with only slightly less temperature resistance. This is not really an issue here because its still rated for 200C and never sees the hot side of the heatsink.

Anyway, here's a photo of the tubing installed. Just thought someone might want to give this a go.

http://www.bwevans.net/files/fepbowdenx1024.jpg

Obviously, this is not a stock eMaker Huxley and I am using a different pneumatic fitting, so as usual YMMV./i]

Cheers-

B

Rich-

The filament pusher is my own design and the verdict is still out on whether or not it is a Good Idea. I wanted to use a geared stepper and stainless steel drive gear similar to makergear's setup so that I knew I had enough force to push filament through the tube and secondly to avoid dealing with hobbed bolts which just seem like a hack and not a solution. It has a hinged idler and open gear facing and uses an M6 pneumatic fitting since Im using an all M6 hot end similar to makerbot. While I should have bought JM's kit I had to make my life more interesting! Once I work with it more Ill post it up on Thingiverse.

Cheers-

B

Found this site with PTFE tubing ID 2mm and OD 3mm, basically the same spec as the xmas huxleys.

£2.70 per meter.

http://www.airlinefittings.co.uk/tubing-hoses/nylon-polyurethane-ptfe-tubing/ptfe-tubing-3mm-15mm-od/ptfe-tube-per-metre-od-3mm-id-2mm/prod_1660.html

You can get replacement bowden tube for the Huxley here http://www.emakershop.com/browse/listing?l=183

Some people have grumbled that the price including shipping is too steep, however airlinefittings.co.uk charge even more for shipping.

Also, the Huxley spares are priced such that ordering more than one item will not incur extra shipping charges.

On the subject of alternate Bowden fittings, you might look at these two, as they are easy to get:

http://www.mcmaster.com/#5225K503 fitting

http://www.mcmaster.com/#5733K52 Tubing

The tubing is a little heavier and the fittings are a little larger OD than the original Huxley fittings, so the hot end will need to be spaced out a bit more from the X carriage to clear the fitting. You can use a nut plate to hold the other one in.

The real Cammozi fitting is 6512 3-M5; the link is below. They cost a couple of dollars each and you may run into a minimum order issue; I just bought 10 and didn't make the minimum to get them sent from the warehouse. My distributor needed some stuff too, so they completed the minimum.

http://www.camozzi-usa.com