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Topic: Melt filters now available

The output side of an industrial extruder looks like this:

http://i.imgur.com/wBEJ0HH.png

The breaker plate looks like this:

http://www.psi-polymersystems.com/images/Breaker_Plate_Asso.jpg

The screen pack is on one side of that, and the die is on the other side.

I've gone through 5 revisions of a combined screen pack/breaker plate/extrusion die, and have come up with the following:

https://dl.dropboxusercontent.com/u/1786359/meltfilter3.png

It uses a 250 micron wire mesh filter, and has 75sqmm of effective filtration area. It is CNC machined out of brass - this in and of itself is an upgrade from the standard nozzles which are made on a drill press. I have tested this final revision for over 100 hours of extrusion, with no measurable decline in output rate. Because the local velocity of the polymer at the screen pack is so low, output rate is not diminished until the filter is nearly full of contaminants.

This melt filter is completely reverse compatible with all versions of the Filastruder - simply heat up the Filastruder to operating temperatures, unplug it, remove the thermocouple, loosen the nozzle 1 turn each minute while the Filastruder cools, install the new nozzle, reinstall the thermocouple, and heat the Filastruder back up. You may need to tighten the nozzle another half turn after heating. Of course, wear gloves and safety glasses during this!

The melt filter is available in the store in both 1.75 and 3.0mm variants. Each melt filter includes two reusable screens, and two retaining clips. You will need circlip pliers to install the retaining clip.

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Re: Melt filters now available

Filastruder Store                        http://www.filastruder.com/collections/all

Marketing 101, oh that's right you were in engineering, hehe

Ralph

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Re: Melt filters now available

Thanks Ralph!

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Re: Melt filters now available

Sold!
Keep up the upgrades and I will buy them

Powder coated steel enclosure, 1/4" Surface grounded hardened aluminum plate, MK2A Heat bed, .200 Polished fused quartz plate, Machined quick change hot bed mount, E3D hot end, Ramps 1.4, DRV8825 stepper motor drivers

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Re: Melt filters now available

Sold! Does anyone want to buy an unused, un-filtered nozzle? :-)

I'm impressed at the rate of improvements to the device. I haven't even received it yet, and I've upgraded the motor and the nozzle! :-)

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Re: Melt filters now available

You probably want to keep the unfiltered nozzle for the initial flush period.

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Re: Melt filters now available

since you want the unfiltered nozzle for the initial flush period I'm guessing you will not make the filter a nozzle option on the kit then? Will you also make the replacement filter screens available separately down the road?

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Re: Melt filters now available

Correct, no reason to make it an option on the kit.

Melt filters come with two reusable screens. If there's demand for more screens I'll make an item in the store. Fewer store items keeps things streamlined.

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Re: Melt filters now available

elmoret wrote:

Correct, no reason to make it an option on the kit.

Melt filters come with two reusable screens. If there's demand for more screens I'll make an item in the store. Fewer store items keeps things streamlined.

With two screens I would think one would be able to re-cycle the screens with a wire brush to clean them up. You would not have to get them absolutely cleaned before reuse after all most filters are most effective when the are at least 50% dirty.

Ralph

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Re: Melt filters now available

Tim will you be getting anymore Kit enclosures(beta) soon?

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Re: Melt filters now available

Yes indeed, except the next run will be post-beta, final edition. I'll announce it here.

12 (edited by innovate 2013-09-15 02:06:28)

Re: Melt filters now available

Thanks, Sounds great Tim

13 (edited by HiTempPrinter 2013-09-16 10:35:55)

Re: Melt filters now available

Tim,

Nice design and machining! And of course, mesh cannot be deformed this way.
It is remarquable how you lengthened the threading to have the mesh at right middle place (heating zone and nipple extremity. I guess you tried difference distances!

Sold.

14 (edited by DePartedPrinter 2013-09-19 19:05:08)

Re: Melt filters now available

Melt filter just showed up. Looks great. Cant wait to it put to use.

*there were a few small pieces of brass still of the inside from where they did the machining.  Probably best to clean this up before using.

SD2 with E3D, SD Press, Form 1+
Filastruder
NYLON (taulman): http://www.soliforum.com/topic/466/nylon/

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Re: Melt filters now available

Got mine installed, everything is extruding just as it was before.

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Re: Melt filters now available

got mine installed yesterday, works great, intentional sawdust and sand contamination tests left clean filament and no decrease in speeds. Filament printed with zero issues and no sign of contaminants. I'd say the filters are a success.

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Re: Melt filters now available

Excellent! What size nozzle did you print with?

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Re: Melt filters now available

.5 and .4 no issues. Layer heights as low as  .1 no problems. 3mm filament BTW, don't have any 1.75 filament nozzles or I'd test them too. today's task is rigging water cooling and air drying stations between my testing extruder and winder.

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Re: Melt filters now available

So a little while ago, I picked up some really cheap ABS that was labeled "trash", as in it had trash in it. Turns out they weren't kidding - this had shreds of all kinds of stuff, like twigs and whatnot. It wasn't a lot by volume, but definitely visible. I decided to run it anyway, to give the ole melt filter nozzle a challenge. Here's the results, after running all 20 lbs:

https://dl.dropboxusercontent.com/u/1786359/Photo%20Feb%2008%2C%203%2005%2020%20PM.jpg
https://dl.dropboxusercontent.com/u/1786359/Photo%20Feb%2008%2C%203%2005%2054%20PM.jpg
https://dl.dropboxusercontent.com/u/1786359/Photo%20Feb%2017%2C%2012%2014%2045%20PM.jpg

The stuff on the towel is only what stuck to the melt filter - most of it ended up in that glob of ABS I peeled off. Then I dropped the melt filter in acetone for a day, and filtered the solution through that towel to show how much debris it blocked from getting in the filament.

I've printed all 20 lbs of it with no clogs. Filastruder output steadily decreased over time, towards the end of the 20lbs I saw about 70% of the normal extrusion speed I expect.

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Re: Melt filters now available

How does filter solves the problem ?
Grinding occurs somewhere creating metal flakes.
What this thing needs is some kind of a guide inside the tube.
If nozzle was metal instead of brass and drillbit had pointy tip at the end, it could be used as a guide. But for some reasons it was cut off. To get it shorter ?

Having such long drillbit pushing filament thru the tiny hole inside very little clearance tube is almost impossible without some kind of a guide at the front end.
Consequences are jammed 0.4mm printer nozzles and ruined prints and worse.

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Re: Melt filters now available

This is also incorrect. Even industrial machines use a melt filter, in fact that is where I got the idea. A guide at the end doesn't help, because often the pellets themselves have debris/contaminantion in them.

The correct solution is a melt filter. Look at an industrial machine for proof.

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Re: Melt filters now available

Sheeesh Tim; you're just making this up as you go along now aren't you.
Industrial machines simply use a rusty basin plug, some stockings as a scrim, unicorn horn dust as lubricant and its all done at room temp. I fail to understand why you've made the filastruder so overtly complicated.

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Re: Melt filters now available

adrian wrote:

Sheeesh Tim; you're just making this up as you go along now aren't you.

Not far from the truth. Luckily there are shoulders of giants to stand on.

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Re: Melt filters now available

elmoret wrote:
adrian wrote:

Sheeesh Tim; you're just making this up as you go along now aren't you.

Not far from the truth. Luckily there are shoulders of giants to stand on.

Now its your turn to have spoiled an otherwise perfect sarcastic post tongue lol smile

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Re: Melt filters now available

Unicorn dust masterbatch would be awesome for making rainbow sparkly filament, but it would probably not be ABS compatible.