Because overengineered is underrated.

Public service announcements

First, some warnings. 

This is not designed with frugality in mind. You will need a LOT of filament. I have limited (kind of) the external hardware, but bear in mind a 6-kilo fully loaded AMS at 40cm from a plastic pivot... well, physics.

Think twice, print once. Seriously, think through the planning of this before printing, and test as you go. I have gone through about seven versions of this, iterating on the design as I went. That does not mean this is perfect; it means it prints well enough on my fleet of A1, P1, and H2 printers, meeting the tolerances and clearances I need. Tolerances are tight. You will need to be strong-willed with a few bits here and there, run them in before proper use.

I used PLA matte black for everything for the aesthetic (I did a couple of bits in PLA tough+ as I iterated), but everything has held up so far. Will it hold up over time? I don't know. Will ASA/ABS hold up better, yep, absolutely, will it print and fit together... Dunno, let me know :D

This is fully tested using my circumstances, your mileage will vary. I have AMS 2 Pro units. I have not tried this with the original version. IF the original is smaller in any direction then, it'll work… if it is bigger in pretty much ANY direction, it will not. The only way this could be accommodated is if it is a few mm bigger front-to-back… But that is a job for future-me.

Background

I got the H2C combo edition: 2 AMS Pro units and the AMS-HT. The bottom drawer used drawer slide hardware (more on this in a moment), and the top was fixed. I needed a third AMS (for the right extruder) and realised I didn't have enough space vertically, so I had to develop the drop slides to allow the AMS to drop forward so the lid didn't contact the next layer up... but then three-high still would not let me open the top AMS to get filament in... What I'm trying to say is that planning on your part is required for options.

Hardware and glue

Drawerslides do not have any hole standards, so I used these; you will need to as well if you want to reuse the screw holes. Yep, they are long. You need to slide the AMS out to the depth of the body, plus the top lid height, and a bit more to open the AMS, keeping the lid open while you fiddle with the filament.

How many screws... I know... There are 136 per layer, but on the plus side, you need way less for the top layer. You will need M3x10 button heads with a head height of 2mm or less. These are the ones I used. Do you need this many screws - probably not, the more you use, the more likely the thing is to stay together though...

Glue though... Glue is a funny thing. Superglue is brittle, E600 is rubbery... I would strongly recommend the use of something like "plastic weld" or weld-on 40" (I think). These are based around a whopping solvent (Methylene Chloride, Dichloromethane, DCM) that melts the plastic at a joint and evaporates, leaving a solid connection. BEWARE the product safety labels. Also, you may need LDPE bottles and syringe needles to deploy this stuff. If you use this stuff, you can definitely use fewer screws. There is only one part that requires some form of glueing, though. If you are looking for more rigidity, all the joined parts would benefit from glue.

Assembly

In essence:

• make all the panels on their own before assembly (base, back, sides, risers, and AMS tray)
• Attach the side to the back
• Attach the cabinet to the base
• Attach the drawer hardware of choice
• Insert the AMS drawer
• Test sliding and wear in things, sand, graphite, etc.
• Insert the AMS
• Stack

For the top layer, you will not need the sides and back, only the base, risers and tray.

Panel prep

The only prep that should be necessary is the joiner block holes. I have not added support, you can... especially if you use a different filament as the interface layer. I have found that a rough pair of pliers to remove the overhang droops does fine. You will need to do that if you're printing on an A1, you may need to do that if you're printing on a P1 and probably won't if you're H2C-ing... my experience.

All parts should fit "very closely together". If you have gaps when you push joined parts together, you will have some slop later and/or tight-running bits.

Flop sliders

These parts will need to be glued before full assembly. The choice of glue is not critical, as alignment pins and screws hold the parts to the risers. Insert a bit of filament in each hole along one half, then use flush cutters the wrong way up to snip off the excess. These bits only serve as a guide and are not intended to go all the way into the parts.

Assembling the AMS tray with flop sliders and bolt hardware

The order here is important if you are using the bolt hardware for the drop sliders. Before you add the runners, you should install the washers and screw the side/riser joiner before the slider, as you will not be able to get to the screws once the slides are in place.

If you are using printed bolts, ensure they are inserted and aligned for optimal layer strength... I'm not sure which orientation that is. Everything has worked so far with the layer lines going up/down, which is good, as this is the only way the front bolts will fit. This is not a problem either way, as the front bolts are not integral to the structure.

Stacking

The whole purpose is that you can add a layer as you go. Joining pins are added in the top of the sides and back, then fit into the riser feet of the next layer up. These are purely for location registration and to prevent sliding during use. The upper layer is loose. For this reason, you should probably zip-tie the units together at the back. I couldn't find an elegant way to do this.

Install as you go. It's easier to finish a layer before attempting to put the next one on and wire in power and PTFE tubes. There is a strain relief hole for a 2.5mm zip tie if you're using the power supply.

You may need longer PTFE tubes. Pull the drawer out entirely, ensure the PTFE tube passes between the AMS and the printer without pulling, then close and check for minimal kinking. PTFE and power should come into each layer under the arch at the top of the back piece. The first communication cable will do this as well, but all other communication cables can stay internal, as there is a fair bit of space.