TradRack - another MMU

[mvdveer]

AS you all know, I completed a very early ERCF build - and I enjoyed it. AS I was limited for space due to renovations, this unit was moved on and I toyed with the idea to build a Tridex. After a comedy of errors, this project was abandoned. Started looking at toolchangers - liked the Daksh tool changer and sourced nearly all the parts, but the one I could not get was the hole magnets. Only available in India and Paypal does not trade in rupees and the Indian sellers did not export to Australia. SO another project shelved. 

@PFarm re-motivated me when he started his ERCF build with all the mods. I ordered and received a Fysetc kit as a starting point.   Started the research on all the mods and it seems a v2 was on the way, incorporating all of these - ah much easier. Well, decided to wait for v2. In the process looked at other MMU units and came across Tradrack. Looked pretty straightforward but was in closed beta. Not any more - the public beta was released and I jumped the gun - Lets build a Tradrack. No sooner had I started and ERCF v2 RC1, a community project was released. (Will have to go down that rabbit hole when I finish Tradrack)

This is my journey in assembling the Tradrack.

[mvdveer]

The public Beta was released with build documents and this is what I followed. Please, the comments that I make in this build diary are my own and in no way a criticism on anyone involved in the development of TradRack. It is there to hopefully make the journey less cumbersome for others. Those with a keen eye will note that there is a color change in the printed parts as we go along. I thought I would support a local Ozzie company and bought some of their ASA (Red and black) However - red turned out to be pink and the stuff printed awfully. Thus reprinted everything after I started the build and ran into problems. (parts cracking, poor layer adhesion, etc) 

The first step is to decide on the amount of rails you want, then use the calculator to give you the dimensions of the extrusion, linear rail , belt length and cable chain length.

Base Frame: Page 8 - 14:

This is a pretty straight forward build. Basically cut /order your extrusion and linear rail to length (as per the calculator) and assemble. The TradRack developers recommend the smaller "c" carriage as opposed to the larger "h" carriage:

The legs that attach to the extrusion has markings indicating L and R - these are important, so pay attention to how they are fitted.

Soaked the rail and carriage in alcohol, lube the ball bearings of the carriage and assembled.

          

Selector Drive End: Pages 15 - 22

Again, nothing too tricky about this - just follow the instructions and all should be fine. The only thing to remember is to solder the wires onto the Omron switch before mounting. You will find that the instructions does not show the wiring as part of the build instructions. Further on, this has caused me some head scratching, so I hope to spare you same. Another comment on the build instructions is that the parts drawn are not proportional to their actual size, and has made me search for large parts where in fact they were actually quite small in reality.

  

Next - Selector Module

 

[PFarm]

 

Thanks for posting this will follow I'd like to build one of these and use this one on the new Trident. Like you got most of the parts on hand.

[claudermilk]

Yes, thanks for starting this diary, I'll be following. I still want an MMU so now Tradrack or ERCF v2.

Nero commented about the idea of rolling spools to avoid runout on his stream last nigh which would be a really nice application. I'm not sure if either of these has that capability in their software (yet).

[mvdveer]

Selector Module - pages 23 - 45

The build was relatively smooth for the first few pages. Important to ensure the base unit is orientated the correct way when assembling the middle carriage to the c-cart.  The back screws are orientated on the side of the motor (back). The four screws that hold the carriage to the cart, needs to be tightened in turn as the back two are restricted by the printed part and as I found caused the carriage to tilt if they are not tightened sequentially. 

At this point I removed the middle carriage again as the next step in the documentation has you mount an Omron levered switch and a small 4mm steel ball in the carriage. These are small parts and I have clumsy hands. Much easier done of the rail, that trying to balance the weight of a Nema 17 motor whilst filling to secure the with to the carriage. Not having the wiring displayed on the sketches in the instructions caused me to scratch my head as to where the wires will exit the carriage.  It should have been obvious - to the back, towards the motor side. Finally figured this out, soldered the wires to the switch, placed the 4mm ball and inserted the switch which caused the soldered wires to break as they scraped along the top edge of the insert cavity. (See the terrible layer adhesion of the filament)

 

My solution was to apply solder to the pins of the switch, mount this, then solder the wires to it at a 90 degree angle. Was relatively easy to do with the outer two pins exposed. Nothing prevents the wires from being soldered on before mounting the switch, other than clumsy hands. This was how I initially tried it but unfortunately fractured the wires further in the build through moving the unit to mount the various components. If you can leave the soldering to just before mounting the selector assembly on the carriage, it will prevent you having to re-solder again.  Once the selector assembly is attached,  the front pin will be obscured and cannot be accessed.

The motor assembly was next and because I did not properly read the BOM (thinking I would have all the screws, washers, shims, etc) I hit a snag. What is it with a 5X7x0.5mm shim? Have plenty of 5X7X1mm precision shims or for that matter 3X6X0.5mm. Luckily the RC Model shop has some, but being Xmas, they were closed for the holidays. I was keen to get on with the build, so I opened fusion, designed the shims and printed 20 of them. Got the callipers out and found the ones that measured 0.5mm, or closest to it. (Range of printed shims were 0.48 - 0.52 Layer height 1.2mm first layer 1.4) Will replace these once I receive the metal shims.

  

It is at this point where you need to ensure the wires are soldered to the switch as after mounting the selector motor, there will be no more access to the switch.

Slide the assembly, the exposed gears facing you, into the middle carriage mounted on the c-cart. 

Next was preparing and installing the servo, well knowing this will have to be removed again for calibration as per this document.

  

Mounted the servo assembly to the selector motor.

 

Next - Filament Lane Module

 

 

 

[mvdveer]

Filament Lane Module - Pages 46 - 49

This is the section where the poor filament came to bite me in the butt. More later. I initially planned for a 6 lane build, but was the linear rail I had, allows for 8 lanes - so why not?  The original lane modules which cracked on assembly of the ECAS connectors:

Reprinted in Polymaker Pollute ASA Red and Yellow (Same settings, other than specifics for PA for each filament) The pink is the local ASA, the red is Polymaker ASA

  

and fitted it to the base unit: (the photos are of the originally printed parts, crack and all - later in the post you will see the replaced lanes)

  

 Next Selector Idler End

 

 

[mvdveer]

Selector Idler end, Belting and Cable Chain  - Page 50 - 59

Very straightforward assembly. The only point of care when printing the parts,  is whether you use 6mm or 9mm belts. Using a 6mm belt requires you to print two spacers for the idler pulley. As I had the pulley and idler in 6mm, I just used this option. 9mm may be a bit more accurate and I may change later. (As always - have printed both options) 

Belting was a different story. One end of the belt as per the manual needs to be attached first - the one on the slot in the carriage - then routed around the motor pulley, the idler and then secured with a screw at the other end of the carriage.

    

With everything mounted, and clumsy hands, I found this task just about impossible. Because of the cable chain mount, you cannot wrap the belt around the bolt and then fit it to the hole, ensuring the belt does not twist in the process. Nor can you fit the belt and then secure it with the bolt as it twists the belt when tightening. You have to wrap the belt around the bolt, then secure this assembly to the middle carriage.

       

I ended up removing the servo, and the arm with the cable chain attachment, fitted the bolt end first,

replaced the arm and servo and routed the belt in reverse to what was described in the manual. No problems doing it this way.

    

Did not have a 10x10 chain handy as per the BOM, instead a 10x11 chain. The mounts from Annex engineering does not have a generic mount (3 hole) option, thus I just printed chain ends to fit the two hole chain solution. 

      

 

Belt tensioning done and the unit assembled with reprinted parts. Red is actually red and the yellow makes it more colourful. (reason for the two colours is I used two different printer to determine which was dimensionally more accurate. Turns out both were, thus used a combination of colours.

Next: Wiring - getting all the plugs fitted, motors and servo connected. Decided to use a Mellow Fly ERCF Canbus board as I have that as a spare from the previous ERCF build.

Already printed the mount, and as this is not a structural part, will not be reprinting it.

   

 

Wishing everyone a happy festive and holiday season and a prosperous new year. For those who celebrate Christmas - a very blessed Christmas to you and your families. Time to spend some time with family and friends and put 3d Printing on hold.

To be continued .............

 

[Dirk]

Wow. Thanks @mvdveer A very concise and yet detailed replication of the manual, with even better illustrative pictures. I think Annex should link you... Or learn from the problems you encountered and adjust their manual.

I think the pink-yellow combination looks great. I wonder how it will function compared to your ERCF 1.1. I see more and more people are extremely satisfied with the improvements, and that only adding the binky encoder on a 1.1 system already solves most problems of tweaking.

Next will be probably the software and tuning. Here is a link I ran into, which already 'mods' the tradrack to work with binky and the happy-hare software. In case you will need it

Best wishes to you too! Have a great time during the festivities with your family and friends.

[mvdveer]

Well had some time yesterday and today and decided to finish the wiring, testing and in effect the build. Used a Mellow Fly ERCF Canbus board so the unit can be operated independently from a specific printer. Can easily be adapted and wired up to any of the printers running an octopus board with Canbus. 

     

     

All in all this was a MUCH easier build than the ERCF v1. The calibration was painless and testing the loading of the lanes went without a hitch.

All testing was done under "lab circumstances. A while back I put together a platform with all the components needed to test 3rd party devices such as the ERCF and now the tradrack, and flashing Canbus toolhead boards.  (SKR 1.4, Raspi Pi with Waveshare CanHat)

Next up (seperate build log) will be the filament cutter. Still need to decide which printer this will go on. Looking at the color scheme it may go on the 2.4 300mm build as the color scheme of that printer is yellow and red. This will be a slow integration as it is not a priority at this stage.

Loved this build due to its simplicity and ease of use. Building and calibration, if I had to choose between the ERCF (V1) and TradRack - I'll go TradRack. Printing wise - cannot comment as I have hardly used the ERCF before moving it on and have not used Tradrack on a printer.

I just LOVE building things - it is my de-stressor.

Thanks for reading and following along.

 

 

[Dirk]

Thank you very much. It was fun to follow this build and informative. 

If I had not already bought the kit and printed almost all of the parts, I would have gone for the tradrack instead of the ercf v2.0

Build-wise, ercf v2.0 compared to 1.1 only has more parts to print and combine together before having a functional component (e.g. the filament blocks in 2.0 have about 6 parts while in 1.1 it was just 2)

I especially love your test platform. A simple but yet complete compartmentalized printer on a plate . 

Ideal to use those useless spare parts! Now I know where that SKR went !

Kudos @mvdveer 

 

[PFarm]

Thanks for posting a very informative document. I'll be building one for the new Trident! I totally get the obsession with building things! Love that yellow and red combo on the 2.4, which filament is that red? Love the lab setup as well great idea for testing components!

Edited December 28, 2023 by PFarm

[Ducky4546]

Awesome! Thanks for posting that build! I had been eagerly waiting for the trad rack to come out it looks like a very elegant solution

[claudermilk]

That went quickly! Now I'm very intrigued by the Tradrack. Might divert from looking too hard at ERCF 2.

[mvdveer]

10 hours ago, PFarm said:

which filament is that red?

e-Sun Fire-engine Red

 

6 hours ago, claudermilk said:

Now I'm very intrigued by the Tradrack. Might divert from looking too hard at ERCF 2.

Much less parts to print and less complicated build in my experience. Also a much smaller footprint. This build with 8 lanes is smaller then the ERCF with 6 lanes.

[claudermilk]

17 hours ago, mvdveer said:

Much less parts to print and less complicated build in my experience. Also a much smaller footprint. This build with 8 lanes is smaller then the ERCF with 6 lanes.

Music to my ears. 

[Snympi]

Great build series @mvdveer, thanks for sharing your experiences. I've also completed my Tradrack after Christmas and over new year. Nice to have time to tinker 
I'm also using the Mellow CAN board. This is a much easier and economical design. Using a MGN9 rail that came from my V2.4 when I upgraded to the MGN12 on X, I was able to fit up to 19 lanes - this is more than I needed, but it was so easy to add additional lanes because there are virtually no restrictions to expand (apart from a longer Gates belt).
The change I made was to include the mod which allows the Binky sensor to be included and then Happy Hare V2.3+ to be used given all the improvements Moggie has made. 
Did you set yours up using the Annex software or HH?

Edited January 16 by Snympi

[PFarm]

@mvdveer The manual references the "calculator" it a py file with no explanation on how to run the script. Still learning Linux so not sure how to load into terminal.

Nevermind I figured it out had to install Python on the Mac.

Edited January 14 by PFarm

[mvdveer]

11 hours ago, Snympi said:

yours up using the Annex software or HH?

For the ERCF, I installed Happy Hare as I also use KLIPPAIN, but for tradrack, the klipper module from the Tradrack GitHub. (Just to keep it as simple as possible and also it was installed on my test board and not an actual printer) 

[LukasM]

Hi mvdveer,

 

Nice build and very nice documentation!

Did you get the Tradrack up and running yet, or did you get straight into building the ERCF V2 because you like the build more than the printing?

I'd love to see a comparison between the two, the Tradrack appears a lot simpler but maybe the added complexity is needed on the ERCF?

 

Cheers,
Lukas

[mvdveer]

5 hours ago, LukasM said:

Hi mvdveer,

Nice build and very nice documentation!

Did you get the Tradrack up and running yet, or did you get straight into building the ERCF V2 because you like the build more than the printing?

I'd love to see a comparison between the two, the Tradrack appears a lot simpler but maybe the added complexity is needed on the ERCF?

Cheers,
Lukas

Got the tradrack up and running on a test platform, doing filament swaps and feeding to the extruder. Have not connected to a physical printer yet. As you said, I do like building things. As I had the ERCF (original)  hooked up to a printer, I can emphatically say the tradrack is EASIER to both build and SETUP.  Will see how the ERCF V2 (Community project) performs with all its sensors.

Planning to add the tradrack to the VZBOT. Have all the CNC parts to swap out the plastic and once I start this, I will add the TradRack to the build and update this thread.

@Gundi has two up and running and he may shed some more light on how it actually performs.

[Gundi]

 

Hi,

I have a Tradrack on the KP3S but I don't feel like optimizing it at the moment...

I installed the second Trad Rack on the Rook.. here it works quite well with the original TradRack software, except that I get a "Timer to Close" error when I have a print with a lot of color changes..

But I have too many projects floating around here at the moment that I don't get to play around any further.

I finally have to continue my VZ conversion

 

Edited January 27 by Gundi

[sakitume]

Hello all, first post here. I stumbled across this build diary and was impressed at what was shared along with how it was shared (pictures, good writeup, etc) and thought I'd join this site to say "Well done!".

I only started my MMU adventures in Nov last year and by then the TradRack was in closed beta so I ended up building a customized ERCF with a variety of mods. That has been a great project and lots of fun to build and make work. In the near future I hope to look into the TradRack in more detail when time allows.
 

[PFarm]

On 12/24/2023 at 6:53 PM, mvdveer said:

 

   

 

Where did you find this Easybird mount? Can't seem to find it. Just finalizing my Tradrack for the Trident really like the design and how compact this is compared the the ERCF. Also, the use of the linear rail over the bearing and rods used in the ERCF, rails is much smoother. I like your idea of the test bench and going to set one up for configuration testing and setup. If all works out think I'm going to take the ERCF apart and build another Tradrack for the V2. I've installed Binky which replaces the ball bearing and DF2.

Edited February 1 by PFarm

[mvdveer]

7 hours ago, PFarm said:

Where did you find this Easybird mount?

On printable - here is the link

[mvdveer]

8 hours ago, PFarm said:

I've installed Binky which replaces the ball bearing and DF2.

Will have to look into this. If you do this I understand that you can then use the happy hare software.