101

Re: Filament Winder

Ian, would these be helpful to you? They are pretty cheap and seem like they would work pretty well. They say they are useful for "line following"
http://www.pololu.com/catalog/category/123

SD3 w/ mods:
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.

102 (edited by jesse 2013-06-26 22:34:57)

Re: Filament Winder

I'd like to help out with this automated filament winder project. 

Please let me know if you guys have ideas or if you need someone to test/build.

I'm familiar with arduino and some other programming languages.

103

Re: Filament Winder

I have a couple things on my programming to do list that I haven't gotten to.  One is incorporating a RGB LED to light up different colors to indicate if you are-

Setting the guide's left limit
Setting the guide's right limit
Setting the PID Setpoint for the tension arm
The loop is being pulled up
The loop is being let down

Also I'm using two hall effect sensors to count rotations of the spool.  When the first sensor is triggered, it sets hall_a_mode to 1.  Then when Hall B is triggered, if hall_a_mode is 1,  it marks a rotation and sets it back to 0.  Then if Hall B gets polled again while the magnet is still in range, it sees that hall_a_mode is still 0 and doesn't mark the rotation.

It's overly complicated, it would be simpler to use one sensor, and then make it wait a set amount of time before polling again.  However I want to be able to use the winder manually apart from the extruder and spin it fast, maybe with a drill.  The wait time needs to be short enough that it isn't still waiting when the magnet comes back around during fast spins, but not so short that it polls again when the magnet is still in range.

The code is in another post here somewhere, and also on the Thingiverse page.

Also I would love an Arduino port for this Filament Width Sensor- http://www.thingiverse.com/thing:89044
It would be useful for the winder, either as is, or as a base to build off of.  However Arduino is my introduction to programming, and I don't know enough to adapt what he's done to an Arduino platform.

104 (edited by jesse 2013-06-27 02:49:50)

Re: Filament Winder

I'll try to separate the problems, find/prototype some solutions, and post the results here.

FYI, this is a tool for measuring filament diameter: https://sites.google.com/site/marthalpr … al-caliper, would be nice to find one that measures circumference

105

Re: Filament Winder

I would like to eventually work that in to my spring loaded caliper, maybe turn one of the bearings into an encoder somehow and keep a log of filament diameter. The value of the filament measurement by reading it's shadow, is that you can use it to measure the melted filament as it is extruded without touching it.

106

Re: Filament Winder

Hi Ian,

I appreciate the efforts you're putting into this winder.  I do however feel that at the moment there is lots of information spread over various places (this forum topic, Thingiverse, your blog - Solidoodle Tips), are you able to share an idea of your future plans?  Are you going to put consolidate plans somewhere?  Or put together a beta programme or Kickstarter as many have asked?

Regards,
Craig

Masterbatch, ABS and PLA Pellets available for UK and Europe.
http://www.emakershop.com/Seller=1324

107

Re: Filament Winder

At the very least I think I want to offer an electronics kit, since that is the most complicated part.  The rest is bearings, threaded rod, motors, stuff that is easy to get though maybe not all from one source.  If I can supply assembled boards for the controller and sensors, then a user would only need to crimp some connectors on wires.  I'm trying to figure out if I can make a board that incorporates an arduino, usb adapter and connections for the winder at a decent price. 

I could send bare PCBs and parts for the user to assemble, but that would cut down on the number of customers because of "OMG Soldering!" .  Putting together boards myself sounds like a hole I may never climb out of, so I hope board manufacturing wouldn't be prohibitive.  I have an initial version which I should be able to complete when some parts show up tomorrow.  It's the first board I've ever had made, so hopefully it won't be simply DOA. 

I have files on Thingiverse because I can't host them on the bare bones Wordpress, so I need to find a better solution for combining files and instructions.  I wanted to get out what I have so far, as sort of an alpha.  If you can get the basic Winder put together, I can pass along a board so you don't have to mess with wiring up a breadboard.  I would much rather tell you to crimp some connectors and plug them in, than make a detailed set of instructions for the breadboard.

I'm still trying some different things out.  I don't want to drill a bunch of 90 degree nozzles, and not everyone has a drill press so I'm giving this a try-

http://solidoodletips.files.wordpress.com/2013/06/photo-copy-6.jpg

Not everyone has a free chunk of wall either, but there are a few approaches that can be taked to make them freestanding.

108

Re: Filament Winder

Wow Ian, thanks that is the first time I have seen your vertical extruder.
I notice there is no fan are you just doing ambient air cooling?
Is the vertical hopper on Thingverse?

Ralph

109 (edited by reesy 2013-06-27 13:25:11)

Re: Filament Winder

Hello Ian,
Id be interested in paying for an alpha testing kit (printed parts and electronics).
PS wall mounting = the other half will definately kill me....
Thanks
James

110

Re: Filament Winder

Ralphxyz wrote:

Wow Ian, thanks that is the first time I have seen your vertical extruder.
I notice there is no fan are you just doing ambient air cooling?
Is the vertical hopper on Thingverse?

Ralph

It's just a Filastruder with a custom hopper smile

111

Re: Filament Winder

I'll post the vertical hopper later when I get to the computer that has it.  I haven't really extruded with it yet since I don't have the winder put all the way back together.   I haven't been using a fan, because it helps to have the filament melted a little longer.  If the filament gets pushed sideways, it has a chance to straighten out rather than instantly hardening with a kink.  Going straight down, it doesn't need the rigidity to cross a horizontal space.   I will add one eventually, maybe to turn on after the loop is stable.

An alternative to wall mounting is putting together some pieces of angled bar from the hardware store -

http://www.homedepot.com/catalog/productImages/300/f8/f8791bbd-be24-4314-ba27-20ccf49f034e_300.jpg

You would need 4 of these at about $8 each.  You could probably make something out of MDF that would be cheaper.  It was easier for me to screw them to the wall than cut up a bunch of wood.  I also now have seemingly vast amounts of workbench space now that those aren't on it anymore.

112

Re: Filament Winder

Hi Ian,

Finally got the kit up and running!

http://www.youtube.com/watch?v=X4xLWxfuMes

Still testing mostly at the moment, I'll keep you updated on results,

certainly a massive improvement so far though!

Thanks again,

Rob

113

Re: Filament Winder

neat...

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

114

Re: Filament Winder

This device seems to be made by the same manufacturer as the digital caliper.

http://www.ebay.com/itm/Digital-Thickne … 4d09413f58

I'm wondering if it has the same 4 pin interface as the tutorial.

https://sites.google.com/site/marthalpr … al-caliper

115

Re: Filament Winder

IanJohnson wrote:

At the very least I think I want to offer an electronics kit, since that is the most complicated part.

Ian,

This great news, thanks for a very detailed response, much appreciated.  I'd be up for being an early adopter of the electronics kit, and more than happy with you plan of locally sourcing the rest (which I prefer, especially as being in the UK means shipping is a pain).

The tracking notice says my Filastruder is in sitting in UK Customs (and has been since early on the 25th), so I am hoping to have it in my hands soon.  I have the day off work tomorrow to play with my toys, so hope it arrives in the morning!!

Keep us posted on the electronics progress.

Regards,
Craig

Masterbatch, ABS and PLA Pellets available for UK and Europe.
http://www.emakershop.com/Seller=1324

116

Re: Filament Winder

Ian,

Do you believe the Filastruder has enough force to push plastic through a teflon tube?

The idea is to let the plastic turn solid by cooling in a high temperature PTFE tube.

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

Attach a section of teflon tube using a push connect fitting to the brass nozzle (M5 .8 threads)

http://shop.seemecnc.com/Push-To-Connec … -38830.htm

The inner tube would be 1.7 mm ID, 2.0mm OD: http://www.ebay.com/itm/230971933777?ss … 1497.l2649

The outer tube would be 2.0mm ID and 4.0mm OD: http://www.ebay.com/itm/321061055446?va … 1497.l2649

The plastic would cool in the tube and get pushed out as a solid 1.7mm filament. 

I suppose the tube could even be coiled to get it to wind around a spool.

117

Re: Filament Winder

I have tried the hell out of that idea, with little success.  I thought if the filament could be mostly cooled as it comes out, it would be easier to wind without worrying about messing it up.  My last attempt was a reverse J-Head.  I tapped the plug at 6mm, and drilled a 1.73mm hole through a 6mm brass bolt before cutting the head off.  I put the bolt into the chuck of my drill press and ran it against some sand paper to level and flatten the end.  I drilled some PEEK rod and tapped one end to take the brass barrel.  I put a 1/4" PTFE rod inside the PEEK, with a hollow set screw at the other end of the PEEK to hold it tight against the barrel.  Then I ran the 1.73mm bit back through the brass barrel to drill the PTFE rod, to guarantee the holes would line up.  I also installed the Filastruder's thermocouple in the bottom of the PEEK up against the barrel so I could control the temp where the plastic leaves the brass.

My thought was that the die swell of the plastic would be contained by the PTFE and it would push out instead at a very constant diameter.  I thought at a high enough temperature, there wouldn't be much swell.  Turns out that friction goes way up as the filament cools toward solid.  When it could extrude at all, it was extremely slow.  Shortening the PTFE helps, but by the time it is short enough to work, the plastic is still fairly melted when it comes out.  It comes out smooth and glossy though, very pretty.

It might work better with more force from the auger.  Also a more gradual taper from the inner face of the die (plug) to the land (the filament-sized channel in the plug) would concentrate more of the force on extrusion rather than pushing on the flat inside surface of the die.  Also a longer land would reduce die swell, so the plastic would be exiting the brass at close to its final size.  It would need something thicker than the plug which is also machined.  Or the brass barrel can be longer to supply the longer land, but it would need some heating, maybe with a nichrome wrap so it doesn't cool too much before getting to the PTFE.

I've tried using a PTFE rod with an ID that is slightly larger than the filament's extruded diameter.  Even a little bit of drag against the  PTFE would cause the filament to buckle or swell just enough to jam up inside.   That idea might work with the vertical extruder though.  It won't have gravity pulling it down against the inside of PTFE the whole time.  With gravity pulling the plastic away from the die in addition to the push from the auger, bumping against the inside of the PTFE might not be so bad.  You would just need to be careful about causing too much die swell from the wrong temp or something and getting it jammed up.

118

Re: Filament Winder

My experience mirrors Ian's. I've even tried graphite loaded PTFE/PEEK blend. No go.

IanJohnson wrote:

It might work better with more force from the auger.

Generating more melt pressure is a big issue, at least more than roughly doubling what it produces currently. Right now it's limited primarily by the COF of polymer to barrel wall, and the barrel L/D. Increasing either would increase melt pressure, then the next problem would be motor power. At that point you'd be beyond the rated PSI for the steel barrel and fittings, and you'd have to upgrade those. You'd also be beyond the rated load of the thrust bearing, at least for the pre SN 133 kits.

To increase the COF, you need either more heaters along the barrel or a rougher internal barrel surface. Both add cost.
It increase the L/D, you have to make the barrel longer. This is actually the cheapest route, though people think the 20" footprint is too large as it is.
Increasing the motor gets expensive. Motors beyond 10w mechanical power are a different tier of cost, from what I've seen.

The cheapest way to boost melt pressure it is to overvolt the existing motor, but you'll cook the brushes in short order if you get too aggressive there.

When I designed the Filastruder, I really optimized each part as best I could to reduce cost without sacrificing reliability or quality of output, while maintaining a high enough output rate to keep up with a couple printers.

119

Re: Filament Winder

Rob,  I put a new servo mount on Thingiverse that goes all the way around the top of the servo and holds it a lot better.  Also I made a version of the guide arm that has a slot down its length rather than a hole.  That's not up  yet, Thingiverse is being weird.  Maybe tomorrow.  The filament is able to move down the slot as the spool fills up rather than drag against the bottom of the hole.

120

Re: Filament Winder

Ian, Cool!

I will print these soon!

Plus one for the PEEK Nozzle, I was doing a little experimenting and almost created a little PEEK nozzle rocket launcher,

A hell of a lot of friction in that little nozzle, and a serious whack of pressure behind it!

Also I will be making up another winder to go with the other filastruder I have ready to assemble next week!

Let me know how the vertical system works out as this is something I might try over the weekend,

Also just so you know, currently I'm not working with ABS, hence the low temps on the filastruder, and strange looking filament.

However when I get the next set-up going this will be for ABS filament so should provide more useful feedback!

Cheers,

Rob

121

Re: Filament Winder

Well I am sure getting an education every time Tim uses an abbreviations without a definition.

Right now it's limited primarily by the COF of polymer to barrel wall, and the barrel L/D

Never did find "COF of polymer to barrel wall", but it was an interesting search and then "barrel L/D" was fascinating. There was even a discussion about converting Barrels of Beer per Day to Liters of Beer per Day.

I would guess COF is something like Coefficient of Friction. I wish I had more time to study all of this but it is slowly sinking in.
Ralph

122

Re: Filament Winder

COF = coefficient of friction
L/D = length divided by diameter
Barrel = the steel pipe the feedscrew is in

123

Re: Filament Winder

Ian, have you tested the winder with 1.75mm PLA?

124

Re: Filament Winder

I tried a little bit, but I wasn't having much success at the extruder end.  It seemed like the temp that would give the right diameter was really close to the point where the plastic was cool enough that it become difficult to extrude.  I think it may need a different nozzle diameter/temp combo than ABS.

125 (edited by Ralphxyz 2013-07-05 00:57:25)

Re: Filament Winder

IanJohnson wrote:

I tried a little bit, but I wasn't having much success at the extruder end.  It seemed like the temp that would give the right diameter was really close to the point where the plastic was cool enough that it become difficult to extrude.  I think it may need a different nozzle diameter/temp combo than ABS.

Oh, now that is interesting.

If we are talking about extruding 1.75mm than the supplied drilled nozzle is drilled with a 1/16" (0.0625" 1.59mm)bit, right?

So what size do you think we need? It seems we need to go larger.

US Number (Gauge) drills

gauge    in    mm
53    0.0595    1.511
52    0.0635    1.613
51    0.067    1.702
50    0.070    1.778
49    0.073    1.854

The next Fractional-inch drill bit size is 5/64" (0.078125" 1.984375mm)

Ralph