14 Jun

Kossel – first prints woo!

building-vase-3

At Last!

Printing has happened! Sample model made in Grasshopper 3d and sliced in Cura using spiral vase (Black magic!)

Its a thing of beauty – well, the bits i’m showing here are anyway! The bits I cropped out are a bit wobbly looking – but that’s due to printer temp i’m sure šŸ˜‰

building-vase-2 Ā building-vase-4 building-vase-5

 

Today I went to SoMakeIT to get some expert advice Ā as it was their 3D printer build day as well. I saw them building their 4th cerberus printer, whilst bugging them to help me out.

 

One of my main concerns was the probing, and that seems to have been rectified! The 40mm fans on the effector were colliding into the X and Y belts, and causing it to skip steps and give very odd results. Some time later we found the part of marlin that allowed us to reduce the diameter or the probing, and now it functions as it should!

One oddity that happend was the extruder, it forgot how to turn! We swapped out the stepper driver and hey presto – its alive. Ordered a couple spare…

I also got some of the connections properly crimped, so I promptly ordered all the parts – I just got a model prepped and ready – only to get ANOTHER temp error! I think that i’m destined to fail, or, I should not assume my terrible wiring wont short at some point! So I turned it off and will wait to do it properly, again.

Will allow me to get the power switch installed, along with the LCD and SD Card functionality.

I should really address the amount of cables coming from the power supply also, would like to neaten that up.

I would like to add some LEDs to the build so I can see what is being printed – I might add them to the ZMin mounts as some kind of arm type thing…

07 Jun

Kossel – more like, blue smoke machine

Well, it has been up and down as far as the Kossel build is concerned – and mostly down at that.

I printed stuff! So at least I have that going for me…

I made a box – it came out surprisingly well! I started printing at 0.1mm layer height and that took ages, I got bored 15 mins into the build.

0_3mm-build-and-leaking

I resent the data at 0.3mm and that took 15 mins to complete – very happy with the finish, some slop on the corners though, due in part to the high temp of the printing and maybe some other variable.. thing is, I didn’t get that far into the dialling in of the printer – as I had sprung a leak on the hot end…Foolishly I didn’t bother to read the instructions in the E3D Wiki – which meant I skippedĀ the final tightening of the nozzle to the heater block whilst at temp.

Video here: http://1drv.ms/1FIYkMP

This meant, once I cleaned and rebuilt the hot end (which wasn’t that much of a chore) – something had gone wrong, I had shorted out either the thermistor, or heater cartridge. Several boards later, and more blue smoke – I finally realise it was the heater cartridge as I don’t have any resistance on that part anymore. I have ordered a replacement and a couple of replacement FETs so I can repair my existing Ramps shields.

This will mean I have to re sleeve – again! so yeah, pretty frustrated – another week down the pan! šŸ™

I also brought a new PSU, costing more than I would like to admit – as suggested by Mark. I picked up a silent ATX PSU and plan chop off unwanted cables, and to sleeve those cables I want to retain.

I have however brought some smallish lengths in wonderful jade, pistachio and grey via the lovely guys at faberdashery – and in order to use some existing woodfill, I just brought a new 0.6mm nozzle. I also brought, at great expense (and since found it cheaper on eBay) some laybrick filament – to simulate a clay / porcelain material. My aim is to get some tutorials done of Grasshopper, a plugin for Rhino, and create some interesting parametric derived surfaces – my justification for this build in Ā the first place!

 

07 Jun

Cardboard Modeling

Final-outcome

The last session we put together was the cardboard modelling sesh, our first workshop in quite some time!

I have run the workshop a couple of time with our undergrads at the AUB, and serves as a good session, introducing the user to several key concepts of model making and concept modelling.

Cutting-the-side-elvations

The goal for us was quite similar, introduce the concept of why we make models of our designs, when we would make models, and to what quality finish we might choose. Ours was dictated by the material we chose, which was a recycled grey board – its a very tough and condensed board, so had its own set of challengesĀ associated with it.Busy-build-continues

internal-windows-cutting

One thing that everyone found out about the material was just how hard it is to cut! We went through lots of Stanley blades in the process, always ensuring we had a sharp edge. Safe use of the equipment was paramount – so getting used to keeping fingers in the groove of the safety rules, and correct disposal of blades. We even got the box of plasters out – fortunately we didn’t need to use it!

Safety-rule

For those a little young to be wielding blades, a pre cut shack was offered and proved a good process to enable precise construction methods.

Construced-laser-model

A-bit-too-much-glue

I use this shack for a range of introductory sessions – one of which is Rhino 3D, and getting the model built ready to use on the laser cutter. I prepared a ‘heres one I made earlier’ and gave a brief overview of using the laser cutter, and we discussed when the laser becomes an appropriate tool, in contrast to making the model by hand.

LaseredShack2

03 Jun

Polargraph/Eggbot/Spherebot Electronics v2.1

I’ve somehow managed to skip from v1 directly to v2.1 with the electronics for my Polargraph.

drv8825_arduino_pro_pcb

With this version i’ve fixed the mistakes and gotchas from v1, rearranged the component layout and changed the Arduino pins used to make routing the PCB easier (no vias!). I’ve also added a connector for an SPI SD card module. I don’t know if I will be able to use the SD card as the current firmware for ATMega328 based Arduinos is pretty much maxed out as it is, but I want to have a go at understanding the firmware and seeing if I can make it any smaller. And if I can then it is better to have a connector on the board ready, than have to add it later.

I also considered adding a connector for an SPI LCD but that would be really optimistic that I can make room for all the required libs.

After blowing up several Arduino nanos that seem to have a problem coping with external power and USB power at the same time, I’ve added a jumper to enable/disable external power to the Arduino. With external power disconnected the Arduino is powered via USB.

Boards are being manufactured by iTeadĀ using their great PCB prototyping service.

I’m also working on a better Polargraph gondola that piviots around the pen and has a quick change pen holder so I can easily do colour changes. I’ll post an update when its all done.