Glue-Gun as Thermoplastic Extruder

It seems to me that the most obvious thermoplastic extruder has been overlooked

Pheobot Wrote:
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>
> (Please tell me if this is not a new Idea, and If
> anyone has done this could they please tell me how
> so I can get more ideas.)
>
It's not a new idea. Vik, iirc, on the core Reprap team explored the idea rather extensively back in 2005. Glue guns were what the Reprap project was working with before Dr. Bowyer developed the Mk II extruder at the end of 2005.

The advantage of the Mk II over commercial plastic welding machines using plastic welding rod was that it was tiny and required very little power to operate.

Don't get discouraged. Read back through the Reprap Blog and see if you see anything that we missed. There are undoubtedly plenty of things that we haven't seen from being too close to the problem.

Thanks for the reply.

It's just that getting a glue gun is alot cheaper then makeing a Mk II. but if the glue gun can't provide a good result then I'll have to try something new.

at 195 degrees celsius, you don't have to use "hot glue" as far as I can see....

If you can get the ABS (or any other plastic you want) in the right diameter, perhaps you could use the hot glue gun.

but... the big problem is that the mechanism used is not very easy to control....

I'm thinking that perhaps a motor with an arm and rod connection might work (thing of the way steam locomotives work by converting linear motion into rotary motion, but in reverse).
So if you had a stepper that had enough torque you could conceivably do this.

-Leav

The thermoplast extruder is a very tricky thing to build especially without a lathe, so having some sort of "just hack a ...." would be a huge benefit indeed.

I recently bought a desoldering gun wich unfortunately has a very small inner tube (1.8mm) so no chance to feed our 3mm filament.
Now I ordered an incar soldering iron (12V 30W) wich I believe would be closer to our needs.
fiy a zhongdi zd-200

If everything goes well it has a hollow heater with an internal diameter of 6mm.

I also send an email to zhongdi corp asking them what would be necessary to custom build a heater for us (including a nozzle, thermistor, and matching brasstube) because the one from the desoldering iron is very well (farnell #1516018) except the small tube; maybe we can special order only "few" custom heaters.


'sid

[edit]
just fixed that ugly typo.. thanks forrest

Edited 2 time(s). Last edit at 10/20/2008 12:59PM by sid.

sid Wrote:
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> The thermoplast extruder is a very tricky thing to
> build especially without a lace
>
> 'sid

And a "lace" is?

pretty sure Sid meant a lathe.

I had acceptable results using the "no lathe" technique that was posted a while back; my first attempt was useable, and I suspect my next one will be even better. All you need is a hand drill, some small bits, safety glasses and patience.

Wade

Wade Wrote:
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> pretty sure Sid meant a lathe.
>
Ah! Okay! I just wasn't connecting this morning.
>
> I had acceptable results using the "no lathe"
> technique that was posted a while back; my first
> attempt was useable, and I suspect my next one
> will be even better.
>
I built a variation on the Mk II with an extruder barrel made from 5/32 hard copper tube. Works brilliantly.

[3dreplicators.com]

Sorry, my fault..
Yes a lathe is what I wanted to say.. I'm unsure why a lace came out.
nevermind, go ahead.

Yes forrest I do have some brass tubing laying around but either I need to braze the nozzle (braze? not brace...? Uh now you got me again...)
or I'll have to tap a thread for the nozzle.
It has to be even easier than that.

'sid

Sid:

I use copper instead of brass for a couple of reasons. The first is that copper is worlds easier to BRAISE (nasty English language spelling conventions make about as much sense as the German habit of capitalising words in the middle of a sentence apparently at random) than brass.

Because of that, braising a piece of thin brass sheet to the end of a thin-walled brass tube is nearly impossible because it is very difficult to get both parts to anything like the same temperature.

I hate the threaded nozzle and threading the extruder barrel into the PTFE and used a compression join instead. Works very well.

Forrest

I got me the brass tube because of two reasons,
first of all I didn't intend to braise the tubing in any way, but i was unsure if I maybe need to tap a thread
second, although I looked around I didn't find any copper tube with 3mm internal diameter and around 6mm outer diameter (different purpose)
And that's why I asked zhongdi.
The pictured replacement heater (without nozzle in the picture) costs about 5-7 Euros that's fairly cheap for a plug and play heater with the thermistor.
So if we could meet something close to that with readymade heater,
the rest is tightening screws so much easier than any other attempt to date.

back to braise braze but not brace
That one wasn't my fault! dict.leo.org told me that braze is correct
I guess you know better than me, but braze is what comes closest to the german word hartl

sid from around the city Wrote:
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>
> That one wasn't my fault! dict.leo.org told me
> that braze is correct
>
Both spellings are correct and used interchangeably. Probably, braze is less confusing because it has no parallel use as a term in cookery.

heh, yeah, I was just going to say something about turkey. Yum!

well in that case..
nothing more to say but:
we got far off topic

Glue guns... glue guns... Oh yes,
Andreas is currently using a slightly modified glue gun
[forums.reprap.org]
Let's see how far he gets with it.
I am waiting for the 12V soldering irons I bought from ebay to see how far I'll get with these.

'sid

I can see how the glue gun's mechanics are all wrong for automatic use, but do you think that the heating mechanism could be modified to take a smaller diameter

not all pheobot, there are glueguns for granules.
they are perfect for other granules like abs or pe

'sid

You don't need a lathe - The barrel is small enough that you can do everything you need to by loading it into a hand-held drill.

I made several that way, worked great. Though I must admit I haven't squirted any plastic yet...

It sounds much harder than it is. I didn't even need a drill-press.

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I'm building it with Baling Wire

Thanks for all your Help. I think I'll do some tinkering and see what I can come up with.

Anthony