Jump to content

RepRap - DIY 3D Printer


simonr
 Share

Recommended Posts

My new project (not as if I need another one!) is to build a 3D printer for rapid prototyping.

I'm building a RepRap Mendel Printer. RepRap is an open source hardware project intended to build machines that can print more copies of themselves - self replicating.

There is more info here: http://reprap.org/wiki/Mendel

Essentially it's a computer controlled, tiny hot-glue gun that builds objects in layers. Although 3D printers are not new - they are just too expensive for most companies, never mind individuals to buy. The print quality is pretty good, but probably only 50% as fine as a commercial machine - but there are loads of people working on improving it - and I have the odd idea of my own!

This is what I've built so far:

post-74-127133789511_thumb.jpg post-74-127133790439_thumb.jpg

At the moment, the most expensive bit is the printed parts. Demand is so high that they are reaching three or four hundred pounds on eBay, but only cost £40 or so to print plus 90 hours of printer time. Most people, once they have built a machine seem to print a couple more sets of parts and sell them to pay for their machine - which is my intention also.

Building it is pretty easy - just a big airfix kit with a couple of hundred nuts & bolts.

My intention for this is to produce prototypes that can either be used to make a mould for casting in Aluminium - or just to prove physically that a design works. The printed parts are quite structural - so with a bit of sanding and spraying, they can be used for many components. I have several Land Rover parts in mind already.

There are commercial machines that can print in metal (a VERY HOT-Glue gun!) and people are starting to be able to print circuits and electrical components - so it's only a matter of time before a machine can print the whole of itself including all but the chips.

I predict that in the future, when you want to buy a new toaster for example, you will buy a licence, download the code and print a new one yourself - a bit 'Star Trek' but it's not that far off!

Si

Link to comment
Share on other sites

Best of luck with it. I've been following the RepRap project for a few years now, and never gotten round to building one for myself. I'll keep watching your progress with interest!

Kev

My brother in law has a metal 3d printer at work, he uses it for prototyping, straight from cad to printer.

Fantastic!

During training he printed a chess piece - a rook - with an internal staircase. Almost impossible to make any other way.

Imagine being able to print a new engine block!

G.

Link to comment
Share on other sites

Looks good Si :)

I predict that in the future, when you want to buy a new toaster for example, you will buy a licence, download the code and print a new one yourself - a bit 'Star Trek' but it's not that far off!

I can see that being a problem in the future. Downloading 'illegal' copies of copyrighted software is one thing, but imagine if you could pirate physical goods....no-one would ever pay for anything again! :P

Link to comment
Share on other sites

Will you be offering a forum discount for printing a new set of parts? :rolleyes:

If you're nice to me I might! I had figured on alternating between listing sets on eBay and offering sets at the material cost - which makes it fair to both people with money but no time and time but no money.

Is it scaleable? Printable furniture could put me out of work.

A printable Land Rover would be interesting.

Yup, totally. The only problem at the moment is the amount of time it takes to print anything. That will improve though.

It occurred to me that if you were to print in a vacuum, you could generate a stream of ions then steer them to the target with a magnetic field (much like a cathode ray tube (old fashioned TV Tube)). That could work for most materials - metal, plastic, peanut butter. It would allow you to print multiple materials at the same time with different ion-guns (similar to how colour TV works with red, green & blue electron guns). Maybe a project for when I have lots of time AND money!

Downloading 'illegal' copies of copyrighted software is one thing, but imagine if you could pirate physical goods....no-one would ever pay for anything again! :P

That's a problem? wink.gif It would certainly turn the world upside down.

There are several people recycling plastic by grinding stuff up into granules and feeding that through the extruder. Think of all the useful stuff you could make out of a Land Cruiser!

Si

Link to comment
Share on other sites

I can see that being a problem in the future. Downloading 'illegal' copies of copyrighted software is one thing, but imagine if you could pirate physical goods....no-one would ever pay for anything again! :P

Edited by Hybrid_From_Hell
Picture removed - this is deemed to be a kiddy safe forum, erm that wasn't
Link to comment
Share on other sites

superb stuff, I've been thinking about having a crack with one of these for ages. I know the yanks having been blowing a huge amount of cash to make one to go into a 12ton truck. They could then print every component in the US millitary from one vehicle!! It's a hell of a thing

Link to comment
Share on other sites

Guest noggy

superb stuff, I've been thinking about having a crack with one of these for ages. I know the yanks having been blowing a huge amount of cash to make one to go into a 12ton truck. They could then print every component in the US millitary from one vehicle!! It's a hell of a thing

thats a bit scary... being able to drive to a war with one truck... and printing an army... thats one hell of a weapon...

think of the fuel it will save!

Link to comment
Share on other sites

Thats well cool.

Looking at the video, does the part need to have a flat base or do you add a pyramid base to be cut off afterwards?

Apart from the noise I really fancy one of those. It kind of goes well with the whole MegaSquirt idea...making stuff yourself.

Look forward to seeing your finished article.

Good luck.

Marc.

Link to comment
Share on other sites

Si, you've rendered my mate useless for the foreseeable future, as after seeing your machine on friday he now won't talk about anything else. :blink:

It's funny you mention using a vacuum, as we were talking about housing the thing in a pressure container so that a partial vacuum could be used to help draw the fluid out of the nozzle. Didn't get as far as the ionic peanut butter guidance though :D

Thanks for the ball, and indeed for the many things to think about.

Cheers,

Jake

Link to comment
Share on other sites

I’ve been contemplating building one of these too for a while, or possibly the other alternative a ‘maker bot’ (which is a kit type, but I believe uses the same control board).

The Ion build up idea is an interesting concept, but I think is unlikely to catch on due to the very low deposition rates you can get out of it. There has been quite a lot of research in that field and various ion deposition techniques are used in semiconductor manufacture amongst other things. Have a look at Nexus for a commercial system!

I’m not convinced we will all be downloading products to print at home for a number of reasons. Primarily, for low cost items made in large volumes like a toaster, it is highly unlikely that the product printed at home will either be cheaper or quicker than going to your favourite supermarket. Where I see it possibly being more practical would be customising the case of your toaster (a whole world of Pimp my Toaster could open up!)

History also shows us that although a tool may become accessible, and open up the ability to make something at home, most people don’t do it. I see it staying as a tool that opens up new possibilities for those of us who take the step to create something to use and create new and interesting projects.

Link to comment
Share on other sites

History also shows us that although a tool may become accessible, and open up the ability to make something at home, most people don't do it. I see it staying as a tool that opens up new possibilities for those of us who take the step to create something to use and create new and interesting projects.

I had almost exactly that conversation in the early 90's when I bought a HP500C colour InkJet (more or less the first one on the market). Why on earth would you want to print in colour? The thing that really turned it around was digital photography. Then there was a demand and a solution. Who these days sends their film to Boots and waits two weeks for prints?

I agree that in today's world, nobody would consider printing their own toaster. However, in a world with less oil, it will become prohibitively expensive to make something 5000 miles away, wrap it in oil based packaging and transport it will seem similarly ridiculous.

It will start out with people printing things like mobile phone cases and models for school projects but as the technology advances, so will the applications.

Si

Link to comment
Share on other sites

When someone works out the equivalent 3D camera / LIDAR project I suspect things will get very interesting. I've seen a DIY 3D scanner done with LEGO, a webcam, and milk (no, really!).

I've been idly following the project, a few things that I wonder about that have stopped me from investigating too far:

First off, what's the output like, does it need finishing and how precise is it? For example, could you easily print interlocking pieces and slot them together or would you have to hand finish them to make them fit?

Second, is this any more useful than, say, a similarly made CNC mill working on a solid lump of plastic? I can't help but feel that even a DIY mill would be likely to give a more accurate finish, by nature of being a machined surface rather than made from blobs.

Anyone tried it with chemical metal yet? :P What about casting wax - print the part in wax, set it in sand, pour in metal.

Another idea for metal deposition would be to use a welding head and put down spots of metal. Might take a while but could presumably be done with reasonable accuracy.

Link to comment
Share on other sites

When I was at uni there was a system which used a digital camera and a template to take photos of an object from predetermined points, which were then used to build a 3d model. This was at least 6 years ago, and needed nothing more than the camera and a printed sheet of paper, so there must be a more accurate system than this available now.

Si said that the corn-starch material commonly used in the rep-rap will virtually vaporise at the temperature of molten ally, so is more than good enough for lost pattern casting.

I've seen a system (Not in a rep-rap, but could be adapted easily) that used something half way between araldite or epoxy and 2-pack paint, mixed with either ground/powdered glass, stone, plastic or metal. It was being used for architectural sculpture, but was strong enough to use for other stuff. Also, the plastic repair kits that motor-factors sell (Super superglue, mixed with powdered plastic) make an insanely strong substance. I was trying to pull the tester apart, and broke both the plastic part and the board it's stuck to, but couldn't even chip the bonding agent!

Link to comment
Share on other sites

Second, is this any more useful than, say, a similarly made CNC mill working on a solid lump of plastic? I can't help but feel that even a DIY mill would be likely to give a more accurate finish, by nature of being a machined surface rather than made from blobs.

There is a limit to what can be achieved with 3 axis machines. Even relatively simple items will require minimum 2 ops whereas the 3D printer achieves compound drillings/features with ease and even complicated cores in one hit. 4 and 5 axis machines would probably be well beyond DIY territory

4 valve per cylinder V8 heads anyone? :)

Link to comment
Share on other sites

The thing that made me look at this in the first place was wanting to make a prototype object which curves in two planes. This makes it very difficult to hold in a mill as there are no parallel sides and there are not two parallel axis holes on any face. The number of jigs (which would be difficult to make in their own right) make the whole thing too difficult.

I was quoted £2k for a single prototype made on a 5 axis mill - so I thought a 3D printer would at the very least solve the prototyping problem.

I have a 3 axis CNC Mill - but this gives something completely different. People don't realise how much setting up is involved milling even simple things.

The surface finish of items isn't brilliant - but with a bit of sanding, particularly on curved surfaces, you'd never know it's been printed.

Because the plastics used have a low melting point, you can often use them directly for the equivalent of lost wax casting. Many people use a part to make a Silicone mould and cast in Polyurethane - which will also be useful.

Si

Link to comment
Share on other sites

I have already been involved in some work on the reprap system where it has been depositing a 2 pack rapid set epoxy type material, the hardware to do it can be easily added to the standard system, as can a simple router/milling head, although you wouldn't be milling out any steel parts due to its limited rigidity. Could possibly connect a plasma to it tho, this has also been looked at, thats the nice thing about a cartisian bot, it will move a "something" to where it is told to in space.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy