Before buying the Anycubic ‘D’ Predator, I purchased an Anycubic Linear Plus. I’d been after a delta type printer for a while, after becoming fasinated with the way they work. After all these years, I still find 3D printers mesmerising as they lay down plastic.

As a printer, I’ve generally been happy with how it performs, but I’ve found its bed size a little bit limiting. Its also limited in its processing power, as its fitted with a trigorilla 8-bit board which is being pushed to its maximum capability by the delta geometry.

The design of the Linear Plus is that all of the electronics sit under the bed. This can lead to the electronics being submitted to more heat than would be preferable. It also has a very long bowden tube ~700mm long which requires long retractions of at least 5 or 6mm to eliminate stringing and if you want to move into more flexible materials, its definitely too long.

Required Printables

Before carrying out the conversion, a number of items require printing. If you don’t have another 3D printer, these will need to be made before you start stripping the printer down. They are as follows

Required Vitamins

You’ll also need some extra parts.

The Frame – Strip Down

First thing I wanted to be able to achieve was to flip the frame so the electronics were at the top. This would give me easy access to the controller if I wanted to make adjustments to wiring etc without having to remove the bed. This would mean that in theory, I would never have to remove the bed again, reducing any requirements to probe the bed for calibration or meshing.

I’m not going to go too in depth into what I did to achieve this conversion as most of it is self explanatory. What I will do, is provide a brief overview of each step I carried out, in chronological order.

  • Remove the effector, along with the arms.
  • Remove the belts
  • Remove the endstops and associated wiring for them
  • Remove the bed, bed clips and associated wiring
  • Remove the linear rails, making sure to not let the runner fall off the end (because if you do, out come all the ball bearings!)
  • Measure the distance from the base of the frame (where the bed sits) to the bottom of the plastic stops which sat under the linear guides. From memory, mine were roughly 70mm.
  • Remove the PSU and associated bracket.

This leaves you with a frame and some electronics. As I was changing the controller board, I also stripped out the controller and screen. This left me with a frame with some motors attached.

The Frame – Assembly

I’d previously printed some feet for the Linear Plus, so the first thing I did was swap these over to the other end of the printer. I then turned the printer so it was now the way up I wanted. I then installed things in the following order.

  • Set the plastic stops to the correct height for the linear rails
  • Installed the linear rails the correct way up (denoted by the orientation of the rod mounts)
  • Installed the endstops at the top of the linear rails. I made sure these sat right against the top of the frame to keep them all consistent.
  • Refitted the belts. I don’t use springs to tension them and instead use the screws at the bottom (originally top) of the frame to move the top and bottom sections apart. I’ve tried to adjust all of them the same to maintain the frame squareness
  • Install the arms and effector
  • Install the 3 sets of mounts to the rod carriages. I also installed one end of the catapult tubing to each mount. The tube should be long enough to reach the centre of the frame if looking from the top. I used 2 cable ties to secure the tubing.
  • Install the extruder to the extruder mount.
  • Install the extruder mount to the tubing. It needs to be tight enough to support the weight of the extruder with little sag. Do the cable ties up enough to hold it but they should still be adjustable.
  • Cut the PTFE tubing coming out of the hotend so it is around 80-100mm long.
  • Fit the PTFE tubing into the extruder. Adjust the catapult tubing so the extruder is held level and in position. The tubing should be under tension but should still be able to allow the hotend to move around the bed. Move the effector around to verify the movement and then tighten the cable ties. If there is lots of spare tubing, cut it off, otherwise leave it incase you need to make adjustments down the line.

That’s the frame assembled.

Duet Installation

Basically, follow the online wiki and my post on installing a duet to the predator. For the endstops, the wires should be connected to the 2 outer pins of the 3 pin connectors. I will post my config on github shortly. Its also worth noting that I am running the duet etc off a 24v PSU that i had lying around. 24v is recommended for the TMC stepper drivers although its not critical.

For the heated bed, I’m using the original power supply connected to a mosfet to control it. I ran cables for the mosfet and the thermistor down the inside of the 2020 extrusion. I will be printing a mount for the mosfet at some point but at the moment its not important.

Photos

Please find some photos below of the finished installation.

So its been a while since I’ve updated you on the status of my predator. Since changing over to a duet, I have a number of further changes to my machine.

The upgrade I’m going to concentrate on in this post is the installation of a duet smart effector. With changing this part I am also forced to upgrade to an E3D V6 all metal hot end, which for me is better, as the one supplied by anycubic is limited to a maximum temperature of 260 degrees Celsius.

So what does changing to a smart effector gain you? I would say there are three main advantages.

  • It makes it easier to change your delta arms to mag mount versions later down the line of the type produced by Haydn.
  • The hotend is now the Z probe. The smart effector has a piezo switch built into it that then uses the pressure of the hotend touching the bed to trigger it. This allows you to call a probing routine whenever you wanted without having to install an extra switch.
  • The smart effector is made from a PCB so it is nice and lightweight but also strong.

To be able to use the smart effector with our machine, a number of extra parts are required if you aren’t going to be changing the arms straight away. I’ve modelled all of the parts required and made them available on thingiverse.

You’ll need to print

  • 1 x converter
  • 3 x fan brackets
  • And 1 of each fan duct. It’s designed in a way that you can choose how many of the fans you fit. I have all 3 installed on mine.
  • You’ll also need
  • 12 x M3 nuts
  • 12 x M3 x 20 screws
  • 6 x M3 x 6 screws
  • 3 x 5015 radial fans
  • 3 x M4 x 30mm screws
  • 3 x M4 nuts.

Make sure you’ve assembled the smart effector as instructed on the wiki.

Start off by running a tap down the 6 mounting holes in the converter for the smart effector. Then mount the smart effector to the converter and secure in place using 6 of the M3 x 20 screws. They do thick out the underside of the converter a fair bit, but that is because we will use them later to mount the fan brackets. Now mount the converter to the 6 arms using the other 6 M3 x 20 screws and the 6 x M3 nuts. You can do this either with the arms attached to the machine or with them removed. Make sure the screws are done up nice and tight so they don’t come loose. Then tap the 2 inner holes on each fan bracket using an M3 tap. Mount the fan duct to the to the fan bracket using the M3 x 6 screws, followed by the radial fan to the bracket using M4 x 30 screws. Repeat for the other 2 assemblies. Finally, mount the fans in the correct position under on the smart effector. Each fan should be wired in parallel and plugged into the part cooling fan port on the smart effector. See below for photos of it installed

For the wiring on the predator to the smart effector, I actually ripped out what was originally there and installed a new harness. This is due to requiring extra cables etc. Just follow the guide on the wiki and you’ll be fine.

Also remember to make the changes to the firmware for the probe and to retune the hotend using M303.

The delta arms supplied by Anycubic are shocking. There are three main problems you will find with them.

  • They are not all the same length
  • The rod eyes on them can be slack
  • The glue holding them together comes unstuck

I have mainly had issues with them not being the same length and the glue coming unstuck. But I have used the glue issue to my advantage.

I would highly recommend removing the whole end from each arm. That’s the black tube that’s glued on the end and the rod eye.

I made a rod setter out of a piece of hardwood and a couple of M4 threaded screws.

The key is to reglue every arm you are using on your printer. The length between the mounting points on the eyes is 440mm. So I separated one end, and using superglue, fitted the end and set them all to the same length using my jig.

One arm was longer than the rest, to the point where I had to cut the carbon fibre tube down to be able to get the end piece set to the correct length.

I’ve had my predator converted to a duet board for almost a week now. It seems to be running really well. I’ve tweaked so I am getting consistent prints. The details are nice and clean etc. I still have some more work to do regarding overhangs, bridges and some slight ghosting but for the moment, its all issues I can live with.

I also seem to be getting the odd layer that doesn’t seem to extrude 100% correct but this seems to be an issue that most people are having and not just on this printer. It appears to be down to the hotend that anycubic use so at some point that will be getting an upgrade. What I will probably do is upgrade the effector to a smart effector at the same time and kill two birds with one stone. Then I only have to order the extra E3D parts required as the effector comes with a custom heat sink.

The above images are of Phil A Ment. As you can see, I still have some issues with overhangs. This will be my next issue to tackle. He was printed at 0.1mm layer heights and 60mm/s print speeds. He took 6 hours to print. I know he has a hole in one foot but that was from me messing around with the print settings on the fly.

The above images are of Cali Cat. Again, the overhang issues can be seen going up the underside of the tail.

All in all though, I am happy with the printer so far. I have moved my config files to GitHub for easy management.

Installing the Duet

At the moment, my duet is sat on one of the mounting pegs that were used to secure the trigorilla pro. Not ideal but I’m waiting for a panel mounted ethernet port to arrive before I go ahead and mount my board properly. Once it gets here, I’ll document the process and post the mount I design to thingiverse. I have already found a mount I like the look of, so I may remix that to make it fit our printer. That of course depends how well I get one with freecad.

That’s all for now. Keep your comments coming.

After building my printer on the dining room table, I knew I would have to move it out into my workspace in the garage. My wife has a “no wires in the house” policy that I have to abide to.

Whilst moving the predator, which is just about doable by myself, I managed to damage the SD card slot. The main annoyance with this is I won’t be able to update the firmware and I won’t be able to use the printer without plugging it in via USB. I could control it using Octoprint but this wasn’t my ultimate plan. This meant that converting the printer to a duet controller has been brought forwards.

I have a duet 2 ethernet v1.04. It’s a controller that I was using to control my Anycubic Kossel Linear Plus. I was planning on selling the linear plus machine, but seeing it next predator, I may just keep it so I have something a little more portable. At the moment, I’ve fitted the linear plus with an MKS Sbase V1.3 but its not performing as I would’ve liked. I may end up buying either another duet or a Bigtreetech SKR.

Anyway, back on the topic of installing the duet to the predator.

Connections

  • There are 4 x motors connections. X, Y, Z and E.
  • There are 3 x optical endstop connectsions. X, Y and Z.
  • There is one probe connection.
  • There is one filament sensor connection.
  • There is one fan connector for cooling the board.
  • There is one fan connector for the 2 sets of fans mounted to the effector.
  • There is one hotend thermistor connector.
  • There is one heated bed thermistor connector.
  • There are bare wires for the heated bed, hotend and power in cables.

Each of the connections need modifying in some way or another to be able to fit them to the duet. One of Anycubics bad habits is to tin the end of the bare wires with solder. This is widely accepted as being bad practice. Therefore, the end of each bare cable needs to be cut off, stripped back and either left bare or crimped with a bootlace ferrule. I prefer bootlace ferrules that are uninsulated so its easier to get them in to the terminals. You’ll also find this applies to the cables which run to the heated bed mosfet.

The endstop wiring needs to be wired differently in the connector to work with the duet. The three images below are from looking at the connector from the top as it it was connected to the board.

The above images show the original connector on the left and the duet connector on the right. Apparently, Anycubic haven’t been consistent with their wire colours so just check your cables match mine. Otherwise use the before and after pictures to help configure yours.

The z probe connector should be wired as shown below. It doesn’t matter whether your wire colours match mine as its just a mechanical switch.

The filament sensor should be wired as shown below. Same principal applies with the original on the left and the duet connector on the right.

The motors can be wired as they are. The duet wiring shows the red and blue connectors the other way round but this doesn’t matter and can be wired in the order they are installed on the trigorilla pro.

Fan connections at the effector end of the wiring

The only connections that need any major change are the fan connectors. The trigorilla connector had both set of fans ran off one connector, but the duet doesn’t have this capability. All three fans are connected together using the positive as shown in. The duet switches the fans on and off using the ground connector so you may be able to split off the negative for the one fan and have that in a single connector. I decided to run another cable and fully separate out the fan. The wires are as follows:

  • Red – Fan 2 (Hotend fan) ground
  • Blue – Fan 0 (part cooling fans) ground
  • Yellow – Positives for all 3 fans wired together.

You can now connect everything to the duet. I separated out all 3 fans. The part cooling fans are connected to Fan 0 and Fan 2 and the hotend fan is connected to Fan 1. The z probe is connected to E0 and the filament sensor is connected to E1. The rest should be self-explanatory and if you get stuck, use the duet wiring schematic here.

Here are my config files for the duet. I now have a GitHub repo with all of my config files. The only one that may need adjusting is the filament sensor as I have not tested this yet and it may need changing from active high to active low.

When turning the machine on, home all the towers. Then go through the delta auto calibration and you should be good to go.

Assembling the printer

After unboxing the printer and taking an in-depth look at all of it’s components, it’s time to put it together.

One thing I’m not going to do here is write about how I put it together or even take photos of the process. Due to the way the kit has been put together, there are very few steps to the process. You put the uprights on the top part, attach the bottom parts and then install the effector. Job done. The manual supplied by Anycubic is very detailed for each step. They also have a video you can watch and follow which details each of the steps.

So of you’ve built a linear plus as I have, which was easy enough in itself, this is even easier. It definitely puts this printer in the newbie category.

Loading the Filament

Once assembled, the next thing to do is load some filament and calibrating the bed. I think in the video is shows how you should cut the filament into a point but doesn’t necessarily say to do this in the manual. It’s a very good method of aiding the loading of the filament. I loaded the filament in as far as possible, rather than just into the extruder as the manual suggests.

Cleaning the bed

Before you start to print anything, I would suggest cleaning the bed. Heat the bed up to 100 degrees Celsius and let it sit there for 5 or 10 mins. You may notice a chemical smell but this is normal. Then get yourself some cleaning alcohol and a cloth and wipe the bed. You’ll thank me for it later down the line. There seems to be some sort of film left on the bed from the manufacturing process which prevents the filament from sticking.

Calibration

On to calibration then. I personally am impressed by Anycubics method of calibration on their printers. The way it’s mounted, under the hot end by a magnet, makes it very repeatable and non susceptible to effector tilt. The only downside is that you have to manually fit the switch to run a calibration. If you want to run it at the start of every print you have to be there, you can’t just set it off and walk away. Also, the position of the screen at the top of the printer is too far away from the hot end when you’re going through the first few steps of the levelling. As part of the process, you have to set the distance between the hot end and the bed using a piece of paper. Once set, you then fit the switch and it goes through the levelling process. But every time you want to level the bed you have to go through the process of the paper check with the hot end. If you’ve used any other form of auto calibration on other firmware’s, you’ll know that you shouldn’t have to do this every time you want to check how level the bed is. Luckily, you can bypass the paper thickness by connecting to the printer by USB and running G29, but it shouldn’t be this way. The whole levelling process also seems to be the wrong way round. The typical process is level, remove the switch, lower the head to the bed and check the offset, adjust if necessary and then relevel. For this firmware you set the nozzle position, level the bed and then adjust the nozzle head during the first print. It just seems odd, but unfortunately, due to the type of electronics used, this can’t be changed without changing the whole controller.

All the calibration completed, I printed the calibration test piece. Nothing to say about that so on to something I’ve sliced. One thing I will say though if you watch the video below is that the flying extruder vibrates a lot when on the very outskirts of the bed.

The manual comes with some suggested settings for Cura. It’s made slightly difficult due to the fact that the version of Cura used for the screenshots is a lot older than the current version. This means all of the screenshots are out of date. In reality, there’s not much to change and the manual can be followed.

The first print

The first thing I decided to print was a calibration cube, just to see how it looks. It has some overhangs etc and I find that square things tend to suffer with ghosting from acceleration and jerk.

It looks better in person. I also know there’s something strange going on at the base near the ‘X’. I think what I need to do is tighten the belts etc. But as a first print, I think its very good.

And here’s a video of the same print.

I will say it now, this printer is very noisy. Straight away you will notice that the fan for the power supply is on all the time. Then, because the controller board has A4988’s, the stepper motors are very noisy. It took me back to my first printer about 8 or 9 years ago.

I next decided to have a go at printing a benchy. Again, I think it was rather a good print. There was little to no stringiness from the filament, so the retraction suggested in the manual, of 6mm at 60m/s seems to work very well. See some pictures below.

If you look around the opening of the door and around the port hole at the front, there is some ghosting evident. There is also some salmon skin effect on the hull. Now with the ghosting, there isn’t much you can do about this due to the fact that the controller is so locked down. Its very difficult to edit the acceleration and jerk settings. The salmon skin is also going to be difficult to eliminate due to the type of stepper drivers installed.

Conclusions

Great first start but limited by the controller.

There is nothing but praise that I can sing for the frame of the printer itself. It is rock solid, with no movement when printing. The hot end is great for PLA due to the PTFE liner going all the way to nozzle (but it’ll be poor for ABS etc). The effector is solid and we’re all well aware of the limitations of the delta arms supplied. Without a shadow of a doubt, the biggest limitation to this machine is the controller. If only Anycubic had fitted something like a cheap Bigtreetech SKR controller with swappable drivers. If they had, this machine would’ve been perfect. They may have supplied it with A4988’s and some poorly tuned copy of smoothieware or marlin, but it would’ve allowed us to tweak these machines until they sung.

The verdict is, I don’t think the print quality of this machine will get much better with the controller it’s supplied with. If you’re happy with what you see and you just want a machine which works and is middle of the road, then I say buy this. If you’re wanting to improve the print quality further, then just make sure you know that you’ll have to change the controller to achieve this. Fortunately, its only £50 for an SKR controller, with drivers and a screen.

Hopefully Anycubic will listen to their fans and so something about it. But until then, i’ll be upgrading the controller.

It has been pointed out to me that Octoprint doesn’t work out the box with the Anycubic Predator. Fortunately for us, Anycubic has been shipping the new trigorilla pro controller board in Mega i3’s since last year. Since then, Foosel has been able to work out whats going on and get this board to work with Octoprint.

To cut a long story short, install https://gist.github.com/foosel/77e4792921db744a157764f66d1d72a5 the add in from here as a plugin in Octoprint and away you go. I can confirm it works as I am printing from Octoprint on windows as we speak.

Unfortunately, this is just another nail in the trigorilla pro’s coffin.

Update:
To install the plugin, you need to do it via SSH rather than the web interface.
So log into the machine and issue the following

cd ~/.octoprint/plugins
wget https://gist.githubusercontent.com/foosel/924a6518b2dea77c9a6ff1f2561b8bb7/raw/46dcd2cd651817683746772907917b72d0c201a5/strip_m110_parameter.py
sudo service octoprint restart

Hope this helps

So now that my printer has finally arrived, I want to start the hardware review. Here, I will detail each part of the printer, with photos etc to make sure you are able to make an informed decision if you decide to buy one. These printers currently retail for £500 on Amazon.

Electronics

One of the important parts of any build is the type of electronics that are installed. Equally important is the type of firmware that is controlling the machine.

Here’s a picture of the insides of the printer.

The above picture is a close up of the board. The printer uses a trigorilla pro board, which is the same one used on the newer versions of the Mega i3. Positives are that its a 32 bit board, so can handle complex delta printer calculation more easily. It also has the ability to resume from power loss thanks to the massive capacitor in the middle of the board. It also comes with a colour touchscreen similar to the MKS TFT’s. That’s pretty much where the positives end with this board. It doesn’t run any form of mainstream firmware, opting to run the manufacturer chitu’s own firmware. http://www.customize-3d.com/chitu-g-code-explained.html is a lift of all the available M codes to use as they don’t follow accepted conventions, so don’t try and use M codes you would typically use with Marlin. It uses A4988 drivers which have been around a very long time to drive the motors, which results in a very noisy printer, although there are guides on the internet to show you how to fit TMC2208’s as they are pin compatible. If you’re expecting to find a board that can be flashed with a different firmware such as Marlin or Repetier, think again. As of yet, no one has managed to change the firmware on these boards.

Surprisingly, the heated bed is driven from a mosfet add on board rather than through the main controller.

The LCD looks like an MKSTFT and I wouldn’t be surprised if it secretly was one.

Almost forgot to mention that it has a filament runout sensor, which from the feel of it when you install the filament, is just a mechanical switch which is either open or closed.

Power Supply

The power supply outputs 24V at 1000W (41 Amps). It is switchable between 110v and 240v inputs. The fan runs all the time so it is quite noisy.

Motors

All 4 of the motors used have no markings apart from XY engraved on the back. There is no information about what their step degree is but I would guess they are 1.8 degrees.

On a surprise note, the end stops are optical end stops made by geeetech https://www.geeetech.com/opto-optical-endstop-end-stop-switch-p-682.html rather than the mechanical switches used on the linear and linear plus delta’s.

Hotend

The hotend is unfortunately an E3D knock off that has the PTFE liner going all the way through the heat break. This is the same as the E3D lite. At some point you may look at moving to an all metal version if you are planning to print more than PLA. On a positive note, they do provide you with a spare hotend, some spare nozzles (0.4, 0.5, 0.6, 0.7 and 0.8mm in diameter) and some cleaning rods to assist in clearing your nozzles if they get blocked.

Extruder

The extruder is some form of cloned E3D titan extruder. I did try and look for the same one online but I couldn’t find it. Not much more to say really. So far it seems to print ok but it did skip when I was initially loading the filament.

Effector

Fully aluminium. This has 3 fans rather than the 2 found on the linear and linear plus. 1 is used to cool the hot end and the other 2 are used for cooling the part. The let down here is the cooling duct has been 3D printed and poorly at that, which is a backwards step when the linear and linear plus had injected moulded ducts.

Rods

As per the linear and linear plus, they are carbon fibre rods with ball joints on the end. Not measured them yet so I don’t know how accurately made they are, but I would suggest they are no better/worse than those that were supplied with the linear/linear plus were. You also get 2 spare rods, which is helpful if any drop to bits.

Heated Bed

The heated bed seems to be custom made for this printer. I say that because of the 3 wings which have been added to allow it to be secured to the frame. The way it has been secured is a lot better than on the linear delta’s where its held in place by 6 clips (which weren’t the right size). This does mean that it can’t easily be removed, but as all of the electronics are now at the top of the printer, this doesn’t matter. As can be seen from the image above, it can be ran on 12V as well as 24V, but in this instance, 24V is used.

Frame

The frame is very sturdy. The top section where the electronics are uses 2020 aluminium profile. They are connected together using custom plates and covered with steel sheet. The bottom section where the bed sits uses 2040 extrusion. Again held together with custom steel sheet.

The uprights use a profile I have not seen before. You can see from the cap on the end what the shape is like. Needless to say that this is one continuous piece. It’s around 40mm thick and 105mm at its widest point. All the runners come assembled, with the motors and belts etc in place. They also have built in belt tensioners. No more springs on the belts to tighten them.

Looking at the above picture, you may well ask where are the linear bearings. This is where I have to say that unfortunately they don’t have linear bearings. They have bearings which run up the inside of the extrusion.

Now I can hear you crying at this point and I was too when I first realised what they had fitted. But at the moment, all I would say is that the jury is out. They have no slack or movement in any direction and feel very rigid. Lets just hope I’m saying that after hundreds of hours of prints. The belts are the typical stuff, with toothless idlers at the bottom (the motors are at the top of the machine).

Conclusions

The frame is very sturdy. No plastic is used except for the top cover, on a couple of bits fitted to the effector and the extruder. We just need to see how it performs print wise. On to part 2.

The title says it all really. The printer is delayed by another day to tomorrow (Tuesday). DPD didn’t get to the depot in time to catch the van to the next depot. Woo! It’ll only be 3 days late for an Amazon Prime next day delivery!