Retrofitting 1983 Shizuoka AN-SB CNC milling machine, Bridgeport mill, Colchester Bantam lathe and 1982 Tree UP-1000 CNC lathe with modern controls - and other workshop stuff
Friday, 4 September 2026
Canvas upgrade for the Elegoo Centauri Carbon 3D printer?
All these different names are a bit confusing.
The "Centauri" is the open frame version
The "Centauri Carbon" version incorporates a glass door and top and metal side panels ie it is fully enclosed and better for maintaining temperature.
The "Canvas" is the "4-colour printing" feature.
The "Combo" models have the Canvas option fitted but you can also buy the kit to convert your basic Centauri of either flavour to 4-colour.
The guidance on which materials the various models are capable of is a bit inconsistent but I think we can conclude that you don't stand much of a chance with the more "difficult" filaments if you don't have a hood if you've got the Carbon option fitted, due to the fact that having an open top will allow all the heat to escape and you'll struggle to keep the base of the part from warping.
So this sort of justifies fitting a hood if you fit the Canvas upgrade.
There was a big hoohah last year after many customers had prepaid for their Centauri Carbon printer with the "Canvas" multi colour option. This allows 4 different coloured filaments to be loaded in the machine and for those to be automatically switched during the print, the end result being a single part with multiple colours. The uproar was due to Elegoo announcing that in fact they would only be shipping the base model without the multi colour option due to development problems. Result - lots of pissed off customers.
I bought my Carbon printer, happy without the option to print multi coloured parts. It may be early days and/or I've been lucky but so far I've been very impressed with the printer. It's been faultless and the preset filament settings have been largely spot-on.
There was never a clear promise that the Canvas option would become available as a retro fit for the non-Canvas Carbon but recently Elegoo has made exactly that available. It appears the accessory is priced at only £38 as a way of making up for the disappointment. In contrast, the conversion kit for the later Carbon 2 is priced at £98 for the equivalent kit. I'm guessing £38 is the cost price.
This comes with all the parts you need for the conversion of a mono colour carbon to a multi colour Carbon Canvas:
Even at cost price, it's remarkable that they can make and ship this lot for £38 but I'm not about to complain. I ordered it on Thursday and it should be with me early next week, shipping from local UK warehouse.
One item that isn't included is a hood for the top of the machine. The single filament Centauri Carbon machine has a glass window at the top surface but this has to be removed to allow the 4 PTFE tubes to emerge above the machine.
What's rather annoying is that the Canvas kit doesn't come with a hood and they don't sell it as a standalone accessory.
Without the option to buy a top cover, it seems to me that I need to knock one up. Obvs I'm not the first user to have figured that out and there are a few models available on the likes of Printables.
I like this one, as it retains the original glass top cover and also the vented riser that I have already installed.
There are 21 pieces to this, plus a couple of acrylic panels. Looks as if it will require several lengthy sessions to get them all done but I have several days before the kit arrives.
The 3MF files contains all of the parts, so I can import it and delete out the parts I don't want each time I start a printing session. Looks like 4 or possibly 5 sessions will be needed, each of around 12 hours. They can run overnight.
Ooof. Something's not quite right here;
While the parts are printing, I thought I'd assemble them in Fusion and see what they look like, check for issues etc. Nothing against the author of these parts but some of the uploaded content can be "rather mixed" in terms of quality.
This is the underside of the assembly. Those pillar things are intended to mate with the existing "vented riser" - but the one on the left here has an angled face that seems to have been flipped so it results in a narrower face where it mates with that riser.
And this is the uppermost of the 2 rear panels. The top one should have a groove at the base and a flat top. Instead, it seems that it is simply a duplicate of the bottom panel. That's not right.
Here's what it looks like with those features corrected:
But while I'm at it, I can't be arsed to source the acrylic panels that are supposed to be fitted in those 2 windows on the front and left sides. So I'll fill them in - after all, there's a glass panel at the top and I can't even see the left side of the machine.
And here's the final, modified (windowless) assembly.
There are a few minor misalignments but they are neither here nor there and I couldn't go back over the guy's original design even if I wanted to, as the 3MF assembly file is a set of mesh bodies, not parametric models.
It looks a bit shit TBH but that's partly because it uses the original glass top (hence parallel sides) and it's made in multiple parts due to the limited print volume in the machine. Also, The Stupid Fat Bloke made the executive decision to use ABS rather than PETG and Any Fule Kno that ABS doesn't like sticking to the plate without large rafts and good temperature control. Ah well.
Here we are then:
Here's the original vented top. I'm going to retain that.
I may glue this together using pipe weld solvent if it looks like a goer.
Fitting the Canvas upgrade kit:
But first, time to do the actual upgrade on the machine. If that all goes West, there's no point having buggered about with the hood beforehand.
It comes very well packaged. I've never seen such neat tapework - perhaps mechanised?
Little manual tells you everything you need to do, step by step
Replacement board for the head. This has one of the STM32s on it.
The STM32F402 seems to be a China-only variant that doesn't appear in "Western" listings but nonetheless:
Processor Core: ARM Cortex-M4 32-bit RISC with Floating Point Unit (FPU).
Memory: Typically equipped with 256 kB of Flash Memory and 64 kB of RAM.
Clock Speed: Standard internal operation up to 168 MHz (utilizing an external 16 MHz crystal baseline).
Peripherals: Features a single 12-bit ADC, full-speed USB 2.0 OTG interface, multiple timers, and standard communication rails (I2C, SPI, I2S, and USART).
Once the board, motor/gearbox and fan have been replaced, there's a little change required under the base.
I was expecting a Meanwell PSU - but not this time it seems....
The wiring actually looks pretty good.
This little board seems to be the heater controller for the heated print plate. There's an optoisolator, a triac on a heatsink and some basic EMC filtering.
The base and chassis are actually diecast.
Elegoo seem to like the STM32 microcontroller, as it's also present on the print head and the Canvas module.
This is a Samsung eMMC flash memory KLM8G1GETF-B041 (64GB).
Although this short cable is described as an extension, it's actually a crossover patch cable thing if you look carefully. Presumably the Canvas has a different connection scheme to the original Centauri pinout.
Then these spool holders are slapped on the side of the cabinet. They have a rather neat friction clutch that provides a small preload torque to prevent the spools from unwinding.
Each spool now has its own motor and PTFE tube.
Here's the PCBA inside the Canvas module. Yes, that's another STM32 (the 3rd!).
And here's the contraption perched on top of the machine. Looks shit but here we are.
After relevelling (first time in months), upgrading to the latest firmware that supports the Canvas features and loading up some PLA, here's Benchy:
It seems to be working well, despite suffering my attentions over the previous hour or so. We will call that a result for now.
No comments:
Post a Comment