3Drip - Nano UV 3D Resin Printer - LCoS Projector investigation - Part1

This will be a series of posts about experiments testing the development of low cost UV resin based printers. With an aim to deciding what technology works the best for the (low) price and then building a 3D printed Resin (SLA) printer.

The initial focus is with Liquid Crystal on Silicon (LCoS) technology - And a new open-source 3D Printer I'm calling 3DRip 

The end target works cost for 3DRip  is $250. Lets see how good we can make a low cost resin printer :)

Further on we will take a look at other technologies to achieve a similar process, they my evolve into another resin based printer, if the benefits are significant enough.

Background - 

I have always wanted to experiment with UV active resins for 3D Printing. Many DLP projector and LASER based printers are now available and some more reasonably prices resins are now available from Makerjuice and Madesolid

Many years back when b9creations were looking into resin printing I was almost tempted to build up a UV resin printer from a DLP projector. Various projects like Lemoncurry were also being developed, but cost, size and time shelved that as an active project for me.

Fast forward to a time when projectors are smaller, higher resolution and UV resin is really easy to get hold of. I decided to attempt the design of a small machine for detailed 3D printing.

A few machines have successfully been built using low cost LCD panels and UV LED's. LCD panels have a few factors that make them less than ideal. They usually have a UV coating and polarizing films, these may need to be removed to allow UV light to pass through. Resolution is usually low for smaller sized panels, so bigger panels can often bulk up an LCD based system.

Other developers are also working on LCD based resin printers.  So to start I decided to take a look at LCoS based pico projectors. Even High resolution LCoS and DLP based optical engines can now be bought for well under $100.

Portable LCoS projectors are based on similar principals as a DLP based design. Light from an RGB LED is channeled and reflected (bounced) off an LCoS panel around 1/2" in size. Lenses and focus produce a sharp colour image. Many low cost portable LCoS projectors tends to be a 16:9 display with QHD screen resolution of 960 x 540 Pixels. (Getting higher resolution all the time).

I decided on a HYDUNDAI (re-branded generic) model with QHD resolution. I only paid ($105/£68) but recently the price seems to have increased. You can no longer get this specific model from Chinavasion, so take a look over on Aliexpress and do some haggling.

Hacking - 

After checking it operated and giving it a charge (they often have built-in batteries) I started to take it apart.

This one had a lot of very sticky tape holding thin metal panels into a plastic and aluminium frame.

Much of it is battery. A thin PCB with HDMI and power in connection, speaker and the all important optical engine.

Here I have lifted out the optical engine, the cable still connected is for powering the RGB led light source.

Once open it was nice to see a separate optical engine. This means that I can rotate that part to reduce the overall size of the machine required for correct focal distance.

RGB LED rated at about ~3W in total.

Light guide removed.

Very quickly parts were separated and I had to try and remove the existing RGB LED, this was surprisingly a die-bonded device with the culminating optical guide. This had been fixed directly onto the bare LED with silicon or clear resin, breaking the seal would stop the LED from working.

You can see the optical path above that captures all the light from the tiny RGB LED, this is only about 1mm across.

Optical - 

But I wanted to see how the optical guide was made to give some insight into how I could modify it or make another one for a replacement UV LED.

I decided to experiment with a 1W White LED to see how much light I could get to pass through the optical engine and also how best to mount a bigger led for heat control and transmission of focused light.

A neat trick for using these LED's and any similar to this, it that the little plastic cover can be popped off, and what you have remaining is a silicone rubber dome, this can be pressed up against an optical light guide and transmit light very well onto it's destination.

A polished section of Acrylic.

My main concern with LCoS was if enough, or any UV light would successfully pass through the many optical components and reflect off the display panel.

I marked up an aluminium angle bracket as a heatsink and way to mount the optical projector in the printer.

Led was removed from the heatsink 'star'

Add some heatsink paste

Fit and superglue around the edge to hold in place.

Now install the light guide- it's wrapped in black tape here.

Focal testing - 

Refit metal cover.

The last job was to connect it up and power it on.

The reason why I'm doing this and also using a White LED at this point, is to allow the fixed setting of the focus for a picture size normally smaller than the projector focus wheel will allow. - Above you can see the tiny screw thread that sets the focal distance. Normally this projector would only be in focus with a minimum 10"+ sized screen. I want around a 70mm sized screen size.

UV light is dangerous to look at so using a White LED for this part allows me to experiment and take all the measurements I will need to make the projector housing and UV resin tray for the 3D Printer.

Projecting some pixels to get the focus nice and sharp, then a drop of superglue on the focus screw fixes it in place.

I know know the exact distances, angle and elevation of the image - so I can design the 3D printer to accommodate this re-modified LCoS Pico Projector.

Now we can switch over to a UV led in the design to make out 3D resin Printer.

Still designing this one in Sketchup (Jan2015) - but I'm also getting more proficient in solidworks and Autodesk Fusion360.

Cool stuff you may want to know about UV and LED's - 

One of the reasons I never wanted to use standard high-intensity DLP based projector's was that they waste a lot of energy when used as a 3D Printer, they also have quite high running costs. DLP projector's produce a wide spectrum of light, only a small portion will be at various UV wavelengths.

UV LED's should prove to be a better solution. The best wavelength for most UV Resins is around 365nm. Many UV LED's produce light at around 410nm, this will cure UV resins, but if you can find LED's with a 365nm output it will provide the fastest cure time even with a much lower rated power output.

The bulb used in a standard DLP projector tends to use an ultra high pressure (UHP) lamp module. At around $200/£150 each and 180+ watts of power, you will get around ~3000 hours of life and a large waste of electricity.

We should be able to use a single $5/£3 (5 watt) UV LED having a lifetime of around 20,000+ hours

Ultraviolet light has a number of wavelength bands - UVC (100nm to 280nm) and UVB (280nm to 315nm) is not much use to us for curing resin and it's not all that easy to generate either.

UVA light falls in the 315nm to 400nm range, and most UV reactive Resins cure in the range of 350 to 410nm.

The lower the wavelength the more UV curing power it has, so where many DLP projectors produce light from both the visible and UV spectrum it's towards the 400nm range, so it can take a few seconds to cure each layer.

UV LED's or LASERS can be tuned to emit UV light at around 365nm, and that's really ideal to cure many of the resins used today - really fast.

A few companies are starting to use dedicated UV projectors, the Autodesk Spark and Ember platform uses a modified UV projector and the team from Carbon 3D claim to be using a high powered UV projection source for their continuous printing - CLIP technology.

Lastly, resins can also be tuned to cure in visible light, but this has issues as you don't want your resin to start going hard in a well lit room.

Next time we will switch over to a UV led and start to build the 3DRip SLA 3D Printer.


In other news - 

I hope you also had a chance to take a look at some of my Blogs over on Disruptive - There are plenty more to look at now -

You may find my Disruptive blog post about how to finish your 3D prints useful, I take a look at some ways to make your prints look good after printing, and also some of the tools you can buy or just standard tools for processing.

3D Print finishing - do you need a special tool? or can you do it yourself.

(The image above is from an awesome progressive cavity pump I'm tinkering with - using both hard and soft 3D printing materials to get a really good pumping system for chocolate and other fine things) - More on that soon.

BigBox 3D Printer - 

I'm also going over to visit the E3D (BigBox team) next week, I'm planning to pick up a BigBox 3D Printer for some testing and evaluation. - Let me know if you have any questions about the printer.

If you are not aware of BigBox - It's got 15 days to go and looking for more funding over on Kickstarter - with the team from E3D and Littlebox behind it.

I should have lots more things to blog about in the following weeks, stay tuned and don't forget to ask me questions or post your comments, here, on G+ or anywhere else you like.

I'm on Twitter @RichRap3D too.

Back soon.

Rich.

Sli3DR 3D Printer design files up on Youmagine

Hello everyone,

Just a quick update to say the design files, source files and other info are now (finally) up on Youmagine (and GitHub) - Yay!

Yet another 'FreeD' RepRap Printer for you to play with :)

Sli3DR, originally discussed here, (wow! was that really back in July,  sorry for the delay, time is going fast) - files are now posted up on Youmagine Here

Do also take a look at the images on Youmagine to see how to build one, most of the fittings are M3 and M4.

You will need some 20mm Alu extrusions - (sizes on Youmagine) and some M4 V groove bearings (eBay)

I have added Repetier Firmware for it up on my GitHub here

It's also as a RAR archive on the Sli3DR Youmagine page 

Firmware is setup and running for RAMPS 1.4

You can configure Repetier Firmware for other Hardware using the fancy online tool here - Load the Config.json file.

This time, I didn't do a Marlin release for it, if you make one, let me know or just share it.

 I hope you build one, the print results I have had from it are outstanding.

0.2mm Layers - Really great Z -layer registration - finally as good as my Delta's - 
My quest for the perfect Cartesian Z axis is complete... for now.

********************************************************************************

Sli3DR_MAR2014_REV3_012_Final_machine_build.

License, project and contact info -

This Design is part of the RichRap Sli3DR 3D Printer (A RepRap project)

Thank you for downloading, please be aware and abide by the license all these files.

The RichRap Sli3DR 3D Printer uses an Attribution - ShareAlike Creative Commons V3 (CC BY-SA 3.0) - http://creativecommons.org/licenses/by-sa/3.0/

This License is not greatly restrictive at all, so please don't forget to attribute my work and acknowledge.

If you decide to print and sell these or make further changes, improvements or additions, that's great! I want you to do that !

I hope this work has been of some use to you, if you wish to say hello or donate towards further developments please see my Blog here - www.richrap.blogspot.com

Many thanks - Richard Horne (RichRap)

Please feel free to contact me.

My website - www.richrap.com
Catch me on Twitter @RichRap3D
Watch me on YouTube - http://www.youtube.com/user/RichRap2011
Google+ https://plus.google.com/+RichardHorne_RichRap3D/about

Please see www.reprap.org for information about the RepRap Project.
Please visit the RepRap forum - http://forums.reprap.org/

These files were originally shared on  -  https://www.youmagine.com/          

Please support this growing and open community.


Sli3DR What? - Reminder what Sli3DR is -

Sli3DR - (pronounced Slider)
Sli3DR is not a Delta based printer, rather it's based on an intriguing 'unnamed mechanism' that was floating around on the RepRap Forum and G+ last year. Billy ZelsnackIdentified it as used in a very old (Rikadenki) Pen Plotter design here.  A few people have tried it out for 3D printing using off the shelf mechanical parts, I wanted to make it with 3D printed parts and Spectra Line based on this mechanism. 

Edit - This bit's updated for correct back credit of bringing the mechanism to the attention of the RepRap and 3D printing community - David Moorhouse over on G+ showed a cable bot design 1st November 2013, see here -https://plus.google.com/104904818050178236499/posts/WpzzVuULM2z

David's original video sparked great discussion over the mechanism, Tim Rastall Made a great sketch of the 'unnamed mechanism' - still unnamed as far as I know. 

https://lh5.googleusercontent.com/-753_E-QeVmo/UlYKlAfRqGI/AAAAAAAAIEg/Ki-oSosqbEU/w471-h514-no/Unna...

Find out more about David's build over here - http://astro.smugmug.com/Hobbies/3D-Printer-Cablebot/

It just needs a door and it's complete.

Spectra Line - Fantastic stuff.

All the essential 3D printed parts

Designed for an E3D V5/6 hot-end

Hopefully the 3D model of the entire machine in Sketchup will help you understand it, if you decide to build one questions are best asked over on the Youmagine Sli3DR comments page here

Happy Building, and as always let me know if you build one... or thousands.


And a quick grumble about backing up files - I had a hard drive crash last night, and like all disasters with computers it wasted a lot of time trying to restore things. I'm not yet sure how much was lost, most was backed up, but the last 3 months - not so much. I do already know I lost half of the 3DRnano V2 design I was working on a few months back. That caused much swearing and grumpy kicking of things.

Instead of getting too annoyed, I managed to finally release Sli3DR, so at least that's made me happy again. - If you do nothing else tonight, back up your projects to a memory stick, or on-line.

I will be releasing 3DRmega next, (as soon as possible) stay tuned.

Back soon.

Cheers,

Rich

3-way Quick-fit Extruder and Colour Blending Nozzle

Three extruder's and One Nozzle - RepRap material blending

Hello everyone, I'm really excited about this one, I hope you like the results - 

Very first print.

It’s taken a while to get this post written up, but a few recent things have really spurred me on to get it finished.

It’s been over a year now since my first layer selective colour experiments and filament joining, not a month of RepRap has passed that I have not thought about multi-colour/material 3D printing.

I started work on colour mixing earlier this year and had some promising results with a basic, manual setup. Things moved onto other 3D printing developments and I got sidetracked for a few months.

Dual extrusion has been the focus for many machines, but this has some significant problems of alignment and oozing of the inactive hot-end and the fact you cant mix/blend materials with two separate hot-ends.

Background - 

I always wanted a single hot-end with multiple driven feeds, so that’s the focus of this particular development.

Before I forget, the files for this project are up on Thingiverse here.

In recent months we have seen some more movement with filament mixing, Adrian Bowyer and Myles Corbett have done ground-breaking work on both multiple fed hot-ends and mixing of plastic filament. The final Report Myles submitted recently is an essential read, great work indeed.

Another wonderful advanced example of layer selective of colour printing has been this set of stunning 3D printed iPhone cases by Matthew Bennett (norcalbarney).

Photo and 3D printed iPhone cases by Matthew Bennett - Thingiverse

Seeing the work by Myles on the RepRap Blog and the prints by Matthew spurred me to re-start and finish off my own rather elaborate colour blending extruder development.

Stop-Start -

I had previously stopped my development because I was having some issues getting two colours to mix well in the nozzle; I introduced mixing slits and a spiral in the PTFE tubes (in and after the PEEK block) and added steps in the nozzle barrel, it had reasonable mixing results but was very tricky to make up by hand.

The same month I saw that Myles had exactly the same issues with the black and white mixing I decided that not mixing the colours well would produce more interesting effects and give more artistic looking prints. So during #30DOC in June I restarted the development and added three feeder tubes. I had initially intended these to be separately driven Cyan, Magenta and Yellow feed, but after some testing realised that all sorts of blends could be made by running single or multiple extruder's at intervals separately or together.

That’s why I’m not calling this extruder a colour mixing setup. I’m opting for blending together 1 2 or 3 materials to produce some really interesting effects. 

Unfortunately my Antique Lathe died in February, which is one of the main reasons this multi-head hot-end didn’t get further development, but with a bit of work I managed to do everything I needed (all of the following below) with just a Pillar drill and hand-tools.

Introduction Video Part 1 -

Building the Extruder's (X3) - 

I’m using a custom variant of the Huxley sized quick-fit extruder from June’s 30 Days of Creativity, along with Herringbone gears and push-fit Pneumatic connections on the bottom.

Many thanks to RepRap Pro for supplying me with the M6 Hobbed bars, these really are made so well and work perfectly with this extruder as it's a modified eMaker Huxley variant.

Quick-Fit 3-way adapter - 

I was going to design a more complex bracket, but I decided to keep it simple for the first test, and as I had plenty of room on my MendelMax X axis, this was the simplest design to test out the idea.

I know! what a monster!

It’s designed to fit on the Quick-Fit Xcarriage.

3-Way Hot-End - (Version 1 - ... it dies a bit later on, but bear with me, it gets better with V2)

Without a Lathe, I decided that I needed a simple hot-end that clamped together; this would allow easy manufacture and experimentation.

First steps were to make a simple over-sized heating block and using a step-drill I bored a stepped hole in the middle, 4mm at the bottom and 14mm at the top.

The nozzle is a M6 brass bolt with a 0.5mm hole, this is cut down to 8mm long and held in place with an M6 brass half nut.

The filament feed tubes would be held in with a block of PEEK clamped down onto the heating block. 

And clamped to the hot-end with a Stainless steel plate.

 Nice and simple construction.

The PEEK block has three holes (you could have more), drilled on a slight angle so they spiral into the stepped heating block. It uses 4mm PTFE tubes to allow the extruders to be angled around the Quick-Fit X-Axis plate. 

I was aware this was not going to last a long time, but I wanted something simple to test the idea with actual driven extruders first.

I was expecting rope seal adhesive to be a good way to bond the PTFE tubes into the PEEK, but this turned out to be a very bad plan. Maybe my Rope seal is just no good, I still have yet to get any reasonable results using it. Nophead however uses a different brand for bonding his heating resistors without any issues at all, so I may revisit this compound in the future.

Blending nozzle V1, assembled – the Stainless plate is clamped to the heating block using long M3 Stainless screws, the PEEK has some Copper tape wrapped around it to aid cooling.

This only has a single 6r8 Resistor, so takes a few minutes longer to get to temperature than a ‘standard’ sized heating block, but gives a good stable performance when insulated up.

First manual test, very easy to push the separate filaments by hand, this might just work!

I finished the manual tests and mounted it all on the printer, ready for test and calibration.
Testing each stepper driver, extruder, hot-end heating and thermistor feedback took about 1 hour.

I got it all working and 'calibrated' well enough for a first print, when... the hot-end assembly died. :(
It did print the striped heart box shown in the very first picture in this blog, then slowly the tubes started to pull out of the PEEK block.

The Glass rope adhesive was soft and had allowed the tubes to be pushed out, quite a mess.
I really think my glass rope adhesive is bad or out of date, it only ever seems to get semi-set no matter how long I leave it, even at elevated temperature.

Never mind, lesson learnt and I know exactly how I'm going to make the next one -

3-Way Hot-End - (Version 2 - ... the one that didn't die! and worked gloriously well)

The heating block and nozzle worked perfectly, so I'm re-using that. I just need to make a much better PEEK and tube holder -

Start with some raw materials, 4mm PTFE tubes, PEEK and Aluminium bars. I'm saving up for a new Lathe, but it's going to take a while to get a new one. So at this point I still only have a pillar drill and hand tools, here goes -

PEEK was cut, drilled, then filed and sanded in the Pillar drill to get a domed plug.

Aluminium bar was also cut, drilled and grooved (with a hack saw!) all rotating in the Pillar drill. (who needs a Lathe!)... - I still do actually :(

Holes are tapped M4 threads.

Use a pencil sharpener on one end of each tube, just cut a little.

Picture shows, normal tube at the bottom, lightly sanded (500 grit) middle, top is threaded (see below)

Before you try to cut the thread on a PTFE tube it VERY important that you lightly sand the outer surface of the tube or you will never be able to grip and turn it in the die!

It's quite easy to cut the thread, you can use a piece of sand paper to grip on the sanded tube while you rotate it in the die, don't cut too fast and go both directions.

You do not need to use the liquid PTFE, but I had some and wanted to try it out.

The thread is more than enough to hold in the tube, but I wanted to see if the Liquid PTFE made it easier or harder to screw the tube into the PEEK.

It did add some lubrication, but does not seem to make much difference, most of the Liquid is pushed out, but I feel a little happier knowing it was added.

All done, let it dry and trim the tubes at a 45 degree angle to each other and to the walls of the heating block. 


Once cut you must drill/ream out the PTFE tubes back to be 2mm internal bore, it will have narrowed due to the threading and fitting into the PEEK block. Do this very carefully and make sure you remove all the PTFE swarf.

Then you can assemble it.

This time the stainless plate is clamping both the aluminium heat-sink and PEEK, this works exceptionally well, the Aluminium block stays warm and can be fan cooled if required, Stainless plate is cold.

New V2 hot-end and extruder assembly.

I know what you are thinking, how heavy is that lot! well it's not as bad as you would think, the extruders are lighter because of the Nema14 motors, but still, it's a significant weight - Note:- I'm running this on my BIG MendelMax using M8 smooth rods and it's still working fine.

I'm getting an X/Y travel speed of 170mm sec without any issues at all on my bigger MendelMax, I changed the acceleration down in firmware to 4000mm/sec, and set X/Y jerk to 15mm/sec.

I have tested print speeds of between 20mm/sec and 65mm/sec at the moment. It seems to be most happy at around 45mm/sec and a 1.4mm extruder retraction. (using 3 x 1.75mm Faberdashery filaments)

Electronics Expansion -

Ideally you would need to drive all three (or more) extruder's as separate outputs from the firmware and send sets of Gcode commands to enable and mix the colours for the object being printed. That’s all future stuff and quite doable as the next stage.

For now I'm using my standard RAMPS 1.3 setup with a modified Sanguinololu PCB to act as a stepper expansion board.

I decided as a first development to expand a single Extruder channel to drive 4 separate stepper drivers and control these stepper enable lines separately so filament blending could be tested with just standard Gcode and normal firmware. Slightly crude, but simple and very effective.

You still need to populate some components on the Sanguinololu, and fit Pololu or stepstick drivers. Components around the steppers are required, including the Microstepping select jumpers, these should be set to whatever your normal Extruder drive is set (mine are x8)

You do need to make sure each extruder drive has a separate enable line. Some are shared on the Sanguinolou, so cut the tracks to make them separate.

Also use a 4k7 resistor for the enable pull-ups as the main controller has a very weak pull-up (100k) already fitted on the enable line, if you don't fit smaller ones on this expansion board it won't switch the extruder's off quickly when you disable them.

You only need 5 wires coming from the original Extruder driver, Step, Dir, Enable, and +5V.

The Sanguinololu board must have +12V and GND connected to it's normal power rail input.

The 3 separate extruder drivers on the Sangunnolo are controlled by the single enable line from the main electronics. For ease of testing the enable line can therefore be switched on or off for each extruder. Spare output pins from the micro could easily be used for enabling each extruder, but for a proof of concept, switches allow the easiest way to experiment and evaluate performance and operation.

Make sure you set the trim-pot reference voltages to about 0.42v for NEMA14 motors if you are using Pololu setpper drivers. If you are using Stepsticks, that’s turned about 95% of the way around (about 1A)

All ready to go...

Setting the Firmware-

Now that 1, 2 or 3 extruder's will be driven together, you need to set the Esteps in firmware

For me the Esteps are 360 (x8 micro-stepping) for one extruder. So if you want to run a single extruder at a time and switch individually between them, 360 is the correct number.

More interestingly you can run any two extruder's at the same time, so the two filaments are combined / blended together, you still have three output combinations and it's actually possible to swap out the 3rd inactive filament for a different colour while it's printing using the other two, then switch to another set of two extruder's using the new colour/material. to do that the Esteps need to be half the value as you have two feeds both giving half the volume to the nozzl, 1/2 of the number above = 180

And finally running all three at a time can give some great looking prints and different colours from each direction of the object! to do that you will need 1/3 of the Estep value = 120

It's easier to see the different effects in the video than in the pictures below, but take a look at both.

Video Part 2 - Construction and Prints -

Prints!-

You must be wanting to see some prints by now :) - Here you go -

Single extruder feed at a time, Gold, Red and Blue filaments used.

Single extruder feed at a time, Gold, Red and Purple filaments used.

More pots, Single extruder at a time.

The one at the back also had a colour swap of gold for the last section.

Two extruder's at a time, Pink, Blue and Pearl White filaments used.

You can see in this picture, that Pearl White is the common colour and Pink and Blue are alternated as the print progresses. (Ignore the yellow outline, that was the purge from the previous used colours)

This picture shows the two extruder colours and how they work on a printed object, this is the same part just rotated 180 degrees, using Orange and Silver filaments.

Two extruder's at a time, Punk star Pink (Magenta), Electric Blue (Cyan) and Mellow Yellow filaments.

Here you can see Greens, Oranges, darker Blues and Reds in the mix. 

Lots of stretchlets.

Orange and Glitter*.

This shows the same pot, rotated 180 degrees - Using Cyan, Magenta and Yellow.

Lower part of the frog printed with Magenta and Yellow, top has Magenta one side and Cyan on the other.

Frog - Red, Purple and Gold filaments.

Left frog - Pink and Silver.

Orange, Purple and Glitter*.

A Universal Paste Extruder body printed with Red, Yellow and Pearl White filaments (2 extruders enabled at a time). - Same part, just rotated.

Mega Stretchlet bangle, Red, Yellow and Blue, all on together.

Close-up of Stretchlet - see the 'toothpaste' effect.

I used up all my 1.75mm filament stock in these test prints, but I'm keen to build up a whole printer in glorious multi-colour blended wonderfulness!

And Imagine using different materials, soft PLA for modifying hardness or doing a flexible 'hinge' in the part. or Glow in the Dark with a hint of whatever colour you like for daytime and night viewing.
Mixing both ABS and PLA together would be an interesting experiment, maybe one to try at some point.

For now more work getting the electronics a little more integrated and maybe a multi-fed Bowden version?

Other news - 

Raspberries - 
I had the pleasure of presenting at the recent Raspberry Jam in Bristol on Monday this week, (not 3D printing this time around, but maybe next time) it was a splendid evening and we had some really great presentations and demo's. Thanks to everyone that came for the Jam.

And a big thank you to Patrick for giving me one of his first really nice Laser-cut (home-made) Acrylic Raspberry Pi cases. If you don't want to print one, you can get hold of his very nice version here -

Clay -
I do get lots of messages about the Universal paste extruder, thanks and keep them coming, and I am planning on doing much more, both on clay and other materials and also the Peristaltic pump extruder as soon as I can.
I do have Metal clay to try and also Paperclay (very good for low warp - perfect 3D printing material)

Rostock - 
Finally I need to mention the Rostock delta printer. If you don't already know?, go and read all about it , Right now, it's totally Awesome with a really big A.

Thanks as always for reading, and please post a comment or contact me to say what you think.

Until next time.

Rich.