Extrusion Stopped

[Jules]

You do have a point - it costs nothing to try.

We did clean out the barrel and nozzle with a torch this morning - took about two minutes, going slowly, after the half hour it took to get all the stuff together. I'll post another thread with a couple of pics of my hubs in action (he's an expert with a torch, so i asked him to do it so I could shoot some pictures to document the process.)

Since aside from 1 little glob of something brown/black (PLA?), most of what we got out of the nozzle and barrel was just the white melted plastic (And i assume there is usually melted plastic in the barrel, right?), it might not have even been necessary to clean that out. It might have been melted and pushed out with proper extrusion. So this one might have been down to just stripped filament.

But anyway we now have a super clean nozzle and barrel. (Learning a lot with this thing.)

[insta]

If you haven't reassembled the nozzle yet, try this:

Get a Q-Tip and cut the head off, leaving just the compressed paper stick. Clamp this into a Dremel collet (it should fit perfectly). Smear it with cheap dollar-store toothpaste and use the Dremel & Q-tip stick to polish the inside of the barrel. you should be able to get a mirror finish this way.

Whenever I heat-clean the barrels I usually heat them to an ever-so-slight glow (approx 1000F), still 800F below the melting point of the brass, but hot enough to burn off every organic in there.

[Jules]

Yes, I will definitely try that - I haven't reassembled yet, I'm using one of the spares, but that's a great idea and I have both Q-tips and a Dremel.

I use the heck out of the Dremel for cleaning up leftovers from the supports, which tend to stick a little more than I would like. (or maybe I haven't quite got the spacing distance right yet - still experimenting.) The sandpaper cylinders are useless, but I've got a set of diamond grinder tips of all shapes and sizes that do a pretty good job of wearing down excess nubs in tight places. And I plan to try the Dremel heat welding one of these days.

What tools do you guys use the most for cleaning up the nubs from your supports? I had very sloppy results from bridging, so i've stuck to the supports, but they are a bit of a hassle sometimes. I've been getting a lot of good use out of a some inexpensive Xuron sprue cutters and needlenose pliers. But they don't fit into all the really tight spots.

The best trick I've discovered so far is the use of a similarly colored Sharpie to cover up the white spots from where a spot has been ground away or sanded - blends it back in so that is much less noticible, and you can buy a set of 24 colored Sharpies in all shades at any Office Supply store. A quick touch up and no one will ever see the spot without a magnifying glass.

[jimc]

the white spots will go away if you hit it real quick with a heat gun or pass the flame of a lighter over the area.

[Jules]

Cool! I've got lighters too!

[jsc]

I recently got a Dremel, and got overwhelmed with all the attachments. I had to go to their web site to look up each one to see what you would use it for. Tried using an edge reinforced fiberglass cut off wheel, I'm not sure I'm doing it right because it wasn't very effective. Anyway, for removing nubbins and resonance induced corner bumps on mating surfaces that need to be flat, I got a 6 pc. needle file set branded "Project Source" from Lowes, $7. I'll have to try to use the dremel more. Do you have a part number for the grinder tips you mentioned?

[Jules]

Hang on, I'll see if I can find it online - they are not actually Dremel tips, but they are designed to work with the Dremel. (And there isn't a name anywhere on them, of course!)

[Jules]

Okay, found them on Amazon - Pro-Quality 20-Piece Diamond Bur Set for Rotary Tool - Glass, Stone, Ceramic. $4.99

http://www.amazon.com/Pro-Quality-20-Pi ... _hi_text_y

They've got a thirty piece set for an extra $1.50 too - I might look into that one. I really do use them a lot.

[jsc]

Ok, ordering that 30 bit set, because hey, an extra ten burrs for 15 cents each. Plus it's Prime and not add-on. Again, though, I think I'm about to hit another case of tool paralysis with all these shapes....

[Jules]

Yeah, I hear that! .....The main ones that I find handy are the cylindrical ones - those are good for taking off flat layers - you move it gently along the top of the layer just like you are shaving it. You want to be careful not to press too hard or you will start grinding out a rectangle shape in one spot.

The tall pointed cones are handy for getting into tight corners - I'd printed that Z-spring with a 3 layer brim and getting that thing cleaned off was MURDER! The tiny little sharp ones fit into tight angles where nothing else will.

The balls are for reaming out the underside of the edges of holes, or creating a dimple in a flat surface - less use for those, but they're nice to have just in case.

And there are a couple in there that can be used to clean up edges - they have a little lip on them. I usually don't bother with those.

Something to keep in mind with these too - they are for removing product, not finishing it - they are going to leave a lot of ragged threads. But a pass with fine grit sandpaper does a good job of cleaning the bits off pretty quickly and getting a nice edge. (Or even better - raid your wife's cosmetic drawer - I use a fine quality emery board to quickly knock them off and polish them up.)