Where are people?

I didn't know these books, it will have a closer look, thanks for the info!
About plastic recycling, I am definitely thinking about extrusion into filament. I have already found some info about the know-how, but not enough yet. I plan to start a blog as soon as I have all the pieces to tell what I do, I'll put all the info I have on it then.

I really think we could rise the interest for reprap if we target other people than engineers: I am sure that many artists, architects and others would love to have one.

The series certainly has a sort of similarity to RepRap. The instructions take you from making a charcoal foundry from scrap, through casting aluminium, and using it to build yourself a machine shop. Each stage building the next.
Got an old upright compressor tank that'll make a nice foundry at some point. >

I know a few artists, but most are fairly traditional. It's a good idea though, we just need to find the right "hook". It feels it could get too technical or idealistic when putting it forward otherwise. I'll put out feelers with some who dabble in 3D modelling. Do any of the extruded plastics take paint well currently?

I see... but I think it would be even better to release the book to open source and let the people who use it add some info to it. I don't have enough space at home to make my own foundry, but if I ever have a garden someday, I know what to do now.

I haven't made filament myself yet, so I don't know how well it can take additives. I suppose you have to select special additives if you want to change the plastic's colors, that needs a bit of chemistry but I'm sure you can find the info on the net. If you only want to add a layer of paint afterwards, you can find some fixative products to make a solid sublayer on the plastic, so you can paint on it.

Well Dave Gingery passed on a few years back, but his books are still being sold, so I doubt they'll go public domain any sooner than the law specifies. It'd probably be easier to do a new guide from scratch, or just buy the collection.

Something like figurines is what I'm getting back from people, so being able to paint or colour them seems a must.

I have seen several painted items on Thingiverse, it is easy to paint plastics. You just need to buy the adapted paint.

Recycled plastic should not differ from normal plastic, at least for thermoplastics (PP, ABS and all the plastics that reprap can use) and as long as they are clean when recycled. Thermoplastics can be melted and reshaped indefinitely, just like water can be turned into ice and melted indefinitely. So I am pretty sure that you can paint on recycled plastics just the same as normal plastics.

I can't readily see a thread for such recycling. Have I missed it? Would probably be a good point to branch into a separate one if not.

Yesterday I was lucky enough to find someone nearby throwing out a large Fellowes 120C-2 shredder. It's apparently ingested one of it's own clearing combs and jammed, but the teeth look good. If being jammed hasn't burnt out the motor (1/4hp) or stripped any gears, it's capable of eating credit cards and staples, so I think CDs and flattened bottles should get eaten up. It might need to "chew" a bit perhaps though (thinking forward-forward-back-forward-forward-back..). Or need something to do some initial chopping.
If it can do that, thinking the plastic confetti into an agitated hopper feeding one of those old aluminium kitchen mincers, heated and fitted with a single-hole nozzle? It'd probably need a sensor to regulate a motor driving the mincer based on hopper capacity and any thinning of the filament.

---

--
Peter "Sci" Turpin
London, England

Provider of practical solutions.

(Sometimes stellifying Jupiter IS a practical solution)

Derbyshire

About the recycler, here is the link:
[dev.forums.reprap.org]

Maybe you can expose your ideas there, it could relive the thread.

I'm here in Andover, Hampshire. I'm just starting out and plan on using Autodesk Inventor to create my mendel parts from. Does anybody know if there are 2d drawings of the parts that can in turn be made into 3D?

(The Solid Edge models are very good, but I'd ideally like to recreate them using a package I'm comfortable with. It would also eventually allow me to make improvements to the design.)

Thanks in advance,

Alex.

Lionel - Thankyou, taking it there.

Alex - Hiya Alex! Wouldn't it be easier to just import the STL files to autodesk, rather than try and make new 3D models from 2D drawings that would be created from the STL models anyway?

Hi Sci,

Thanks for getting back to me. Having looked at this again at lunch, that does indeed seem to be the best course of action.

I will have to rebuild the Assembly from scratch though as the constraints in the .STL file(s) are lost during the conversion process.

As I do this sort of thing as part of my day job, I think it'll give me a good understanding of the assembly as a whole as well as reinforce ideas I have for improving/simplifying the design.

Thanks again,

Alex.

I'm in Horsham, West Sussex.

My Mendel is only a couple of days away from being operational now. Just waiting on a couple of connectors.

If any of you need help with general machining (free of charge as time permits) I have pretty good facilities here.

Si

I am near Winchester - Hampshire.

Really Really want to build a Mendel Reprap but have to complete a hobby CNC machine first. I started buying bits for many years ago.

I have just had my Birthday so hopefully can fund the rest of CNC machine.
Plan would be to try milling some Mendel parts with it.

Will take me at least another two years of Birthday and Christmas money to get the funds together for a Mendel.

Plan is next years Birthday upgrade CNC to add an extruder etc.

Year after that to fund Mendel - I hope.

So very jealous of all you people making rapid progress

If you are building a cnc mill - then it will, by swapping the spindle for an extruder and using the reprap software, make every bit as good a 3D printer as a Mendel!

Si

If you are building a cnc mill - then it will, by swapping the spindle for an extruder and using the reprap software, make every bit as good a 3D printer as a Mendel!

Generally true, and a very good approach. The drawback is that it may have a slow deposition rate if you have fine-pitch threaded rod. But the plus side is you can do this: [reprap.org]

---

-Sebastien, RepRap.org library gnome.

---

Remember, you're all RepRap developers (once you've joined the super-secret developer mailing list), and the wiki, RepRap.org, [reprap.org] is for everyone and everything!

Hi Lionel,
I'm in Aberdeen too, and strongly considering getting/ building a RepRap. Assuming that I can get permission from the wife, which is the difficult bit.
Elsewhere you mention an AU student group interested in the RepRap. What's the status on that. FYI, a number of years ago I was involved in setting up the Aberdeen LUG, which is still going.

Aidan in Sunny (?) sub-tropical (very) Aiberdeen. Fit like, loon?

Hi Aidan!

I'm glad to see that there is someone trying in here! I've been in touch with the university to try and make a reprap club, but since I'm no longer a student, I had to find some motivated people to start the club. And that is where things got stuck.
If you're motivated to organise a club, I would be happy to help. At the moment, I am building a mendel from lasercut pieces and it should be complete in a few weeks. I still miss some pieces (the teflon bit and the nozzle for the extruder, and the thick sheet parts) but I am not very worried to find them.
I also have some ideas to make a recycler. It seems like many ideas are around and I would like to give it a go. Free plastic filament sounds good...

Hi Lionel,

Quote
Lionel
I'm glad to see that there is someone trying in here! I've been in touch with the university to try and make a reprap club, but since I'm no longer a student, I had to find some motivated people to start the club. And that is where things got stuck.
If you're motivated to organise a club, I would be happy to help.

You may have misunderstood me - although I was a student at Aberdeen, I graduated in 1987 and only visit the uni occasionally now. I did help to set up the AberLUG about a decade ago now (I think I was still on dial-up at the time!) but that seems to have drifted off to Web-2.0-land. They still have monthly meetings in Ma Cameron's bar I think.
The problem with student-y clubs is the annual churn of interested people leaving to go and do other things. (sigh)

Quote
Lionel
At the moment, I am building a mendel from lasercut pieces and it should be complete in a few weeks. I still miss some pieces (the teflon bit and the nozzle for the extruder, and the thick sheet parts) but I am not very worried to find them.

That's great to hear. I'm an offshore worker, and have a reasonable amount of free time in general. We must arrange to meet. Having said that, I'm lined up for a 2~3 week hitch at the end of next week.

Quote
Lionel
I also have some ideas to make a recycler. It seems like many ideas are around and I would like to give it a go. Free plastic filament sounds good...

See separate response.

---

--
Aidan in Sunny (?) sub-tropical (very) Aiberdeen. Fit like, loon?
What grabs my interest ? Making models of fossils which are preserved as rock that ISN'T THERE.

Lionel Wrote:
-------------------------------------------------------
> Recycled plastic should not differ from normal
> plastic, at least for thermoplastics (PP, ABS and
> all the plastics that reprap can use) and as long
> as they are clean when recycled.
In theory, true. In practice, there is often a degree of cross-linking, oxidation and other reactions that also go on when even "pure" thermoplastics are heated in air to melt them. (My Dad was a plastics chemist before he retired.) That's assuming that your feedstock is correctly segregated to start with. In practice, you're likely to get at least some contamination of your thermoplastics with thermosetting materials.

> Thermoplastics
> can be melted and reshaped indefinitely, just like
> water can be turned into ice and melted
> indefinitely. So I am pretty sure that you can
> paint on recycled plastics just the same as normal
> plastics.
Probably correct, the first time around the recycling cycle. But that's more a finishing issue that a fabricating issue.

You'd made various comments about hoping to find out how to use recycled plastic as a source for feeding your RepRap. But at least one site that I've seen today (I'm still studying the idea), says that he thinks that "natural" coloured plastics make the better products "because the dyes and pigments in coloured materials can separate out and boil in the extruder, leading to patchiness, loss of strength, etc."
Now, I don't know by practice how real a problem this would be. But my chemistry background tells me that it's not implausible. Certainly have to watch out for it.

---

--
Aidan in Sunny (?) sub-tropical (very) Aiberdeen. Fit like, loon?
What grabs my interest ? Making models of fossils which are preserved as rock that ISN'T THERE.

too bad for the university. Maybe it will be easier to get something there once we have a couple of machines up and running, though. I PMed you about a meeting time, let me know if you can do it.

RockDoctor Wrote:
> In theory, true. In practice, there is often a
> degree of cross-linking, oxidation and other
> reactions that also go on when even "pure"
> thermoplastics are heated in air to melt them. (My
> Dad was a plastics chemist before he retired.)
> That's assuming that your feedstock is correctly
> segregated to start with. In practice, you're
> likely to get at least some contamination of your
> thermoplastics with thermosetting materials.
>
That's an interesting problem of chemistry... unfortunately I'm a physicist! Even though, I remember that I've seen a way to treat old ABS to make it white again: the chemical used contained some oxygenated water (H2O2) and other things. I suppose that it had a antioxydative effect, but that needs more investigations, and I cannot find that product again at the moment.

RockDoctor Wrote:
> "the dyes and pigments in coloured materials can
> separate out and boil in the extruder, leading to
> patchiness, loss of strength, etc."
> Now, I don't know by practice how real a problem
> this would be. But my chemistry background tells
> me that it's not implausible. Certainly have to
> watch out for it.
Another good point. At the moment, I am thinking of a two-step approach for recycling: first melt the plastic and pour it in 1cm diameter moulds to make cylinders, and then extrude the cylinders when they are still hot (above the plastic transition temperature) to get a 3mm filament. If the plastic contains impurities, it may be possible to separate them by gravity while the plastic is still liquid in the mould. Then you just have to saw the portions of the cylinder that contains the impurities. that is a lot of theory and I think it needs more practice to check how easy it is anyway.

Lionel Wrote:
-------------------------------------------------------
> too bad for the university. Maybe it will be
> easier to get something there once we have a
> couple of machines up and running, though. I PMed
> you about a meeting time, let me know if you can
> do it.
>
PM replied. Let's see what we can do.

> RockDoctor Wrote:
> > In theory, true. In practice, there is often a
> > degree of cross-linking, oxidation and other
> > reactions that also go on when even "pure"
> > thermoplastics are heated in air to melt them.
> (My
> > Dad was a plastics chemist before he retired.)
> > That's assuming that your feedstock is
> correctly
> > segregated to start with. In practice, you're
> > likely to get at least some contamination of
> your
> > thermoplastics with thermosetting materials.
> >
> That's an interesting problem of chemistry...
> unfortunately I'm a physicist! Even though, I
> remember that I've seen a way to treat old ABS to
> make it white again: the chemical used contained
> some oxygenated water (H2O2) and other things. I
> suppose that it had a antioxydative effect, but
> that needs more investigations, and I cannot find
> that product again at the moment.
>
Hmmm, hydrogen peroxide (your "oxygenated water (H2O2)") would have lots of chemical effects in addition to being a fairly effective way of bleaching many dyes. But it wouldn't touch a lot of pigments - e.g. carbon black, or powdered chalk (for white). There's a lot more chemistry in dying plastics (and therefore in undying plastics) than I'd really want to get involved with. It'd be quicker to "suck it and see" than to try to work it out from scratch, and then work out which colours/ sources to avoid.

> RockDoctor Wrote:
> > "the dyes and pigments in coloured materials
> can
> > separate out and boil in the extruder, leading
> to
> > patchiness, loss of strength, etc."
> > Now, I don't know by practice how real a
> problem
> > this would be. But my chemistry background
> tells
> > me that it's not implausible. Certainly have to
> > watch out for it.
> Another good point. At the moment, I am thinking
> of a two-step approach for recycling: first melt
> the plastic and pour it in 1cm diameter moulds to
> make cylinders, and then extrude the cylinders
> when they are still hot (above the plastic
> transition temperature) to get a 3mm filament. If
> the plastic contains impurities, it may be
> possible to separate them by gravity while the
> plastic is still liquid in the mould. Then you
> just have to saw the portions of the cylinder that
> contains the impurities. that is a lot of theory
> and I think it needs more practice to check how
> easy it is anyway.
If you have access to extruding equipment (we'll talk more later this week), then there is the prospect of doing a procedure called "zone refining", where you push your bulk bar through a heated section leading to melting of a "zone", into which the bulk of the impurities separate. As you move the heating element on, the cooling zone allows separation of relatively pure polymer and the retention of the impurities in the melted zone.
It is an effective technique - I'd see Dad doing it a couple of times a decade to concentrate the impurities in a troublesome sample. But it's also hideously tedious (Dad would bring the machinery home to run it over the weekend), slow and inefficient.

The idea of recycling used plastics is interesting, but I fear that you're making a lot of really big sticks for beating yourself over the head with. Big spiky sticks. Big spiky sticks dipped in that special sauce the Viet Cong used so effectively on their big spiky sticks.
To be honest - if I were inclined to follow this path, I'd look at getting stock of recycled plastic from a recycling company (equipment suppliers might wish to take note!) and letting them deal with the very non-trivial task of making sure that the stock is reasonably consistent in composition.

---

--
Aidan in Sunny (?) sub-tropical (very) Aiberdeen. Fit like, loon?
What grabs my interest ? Making models of fossils which are preserved as rock that ISN'T THERE.

Hello,

I'm in Gloucester, it looks like a few from Cheltenham, but not many posts in 2010, apart from annodomini2 if any of you or bristol / bath / swindon are still reprapping, let me know! I'm a bit late getting started, but there must be still lots to evolve in this project.

Cheers,

Rich

Hi, my name is Darren Sim and i'm based in north devon. I've been busy getting all the parts together for my reprap and i hope to soon have something that vaguely looks like a mendel. My material of choice for repstrap is MDF and once the reprap is running my first job will be to print a replacement set of parts . I get the feeling that may be a while off yet! If theres anyone else in the southwest thats working on this project i'd love to hear from you,

Regards,

Daz

Hi

I'm in Essex.
Got all the mechanical parts together to build Mendel.
Made good progress yesterday. X axis completed (ish)

Still need Motors and electronics.

richrap Wrote:
-------------------------------------------------------
> Hello,
>
> I'm in Gloucester, it looks like a few from
> Cheltenham, but not many posts in 2010, apart from
> annodomini2 if any of you or bristol / bath /
> swindon are still reprapping, let me know! I'm a
> bit late getting started, but there must be still
> lots to evolve in this project.
>
> Cheers,
>
> Rich


Hi Rich,

I'm still going if slowly, got most parts bar belts, some form of PWM driver for the Heater, and the ubiquitous RP parts.

I've been working with a guy in the US on a respin of the electronics and software, trying to make it cheaper, simpler from a usability perspective and more reliable. With easy scope to add more features.

Getting married in October so my time is at a premium.

Andy (annodomini2)

Located East Devon no part just an interest.
Have a MDF built router with screws and motors.
Would like to double it up to a rep rap.
Anyone been down this route?
Idealy controlled with an old lappy (XP)
Suggestions welcome

I've been working with a guy in the US on a respin of the electronics and software, trying to make it cheaper, simpler from a usability perspective and more reliable. With easy scope to add more features.

Neat! Link? e.g.
http://reprap.org/wiki/Generation_3_Electronics_Respin, say.

Also, are you subscribed to the super secret reprap-dev mailing list?

---

Have a MDF built router with screws and motors.
Would like to double it up to a rep rap.
Anyone been down this route?

Yup, but the wiki has minimal docs about it. Related but not precisely:
http://reprap.org/wiki/SGBot
http://reprap.org/wiki/Eiffel

You may find threaded-rod reprapping slow, compared to toothed belt motion-control.

Idealy controlled with an old lappy (XP)
Suggestions welcome
Hmmm ... http://reprap.org/wiki/EMCRepRap

---

-Sebastien, RepRap.org library gnome.

---

Remember, you're all RepRap developers (once you've joined the super-secret developer mailing list), and the wiki, RepRap.org, [reprap.org] is for everyone and everything!

Not subscribing anywhere first posting on this subject.
Seems like standard Rep-Rap's do not require connection to a pc anyway, just have code on a data card (SD)?
Perhaps I should just buy a full kit, the thought of something occupying footprint of a print,scan, fax machine sounds good.
Would use for producing small detail parts (Modelling).
Kev S

SebastienBailard Wrote:
-------------------------------------------------------
> I've been working with a guy in the US on a respin
> of the electronics and software, trying to make it
> cheaper, simpler from a usability perspective and
> more reliable. With easy scope to add more
> features.
>
> Neat! Link? e.g.
> [reprap.org]
> spin, say.
>
> Also, are you subscribed to the super secret
> reprap-dev mailing list?
>

Nothing's currently public atm, still working out the requirements

I am not on the dev mailing list

Andy

I'm in Hythe, near Southampton. I don't have a reprap yet - it will be my first major project when my new workshop is built (A lovely log cabin from stablestructures - sept 22, not that I'm counting the minutes or anything) since I just moved here from Soton, and have to start over.

I think the nearest reprapper is somewhere near Chichester, so perhaps that's an ear I can bend when I have difficulties...

This is such a cool project that I just have to get involved to give me something other than work to think about (i'm an IC designer) I can't wait, but suspect finances will be an issue with she who must be obeyed...let's see, she seems to understand why this is important to me anyway