Anycubic Photon Mono 2 mini heater spacer

Introduction

Resin printers are typically kept in cold garages or sheds, as they're messy and smelly. However, this often subjects them (and their contents) to low temperatures, which can make it difficult to print, especially if you live in a climate where the temperature regularly goes below 15C. One way to mitigate this are chamber heaters, such as this one. However, since this requires wiring to be run through the lid, you have to drill holes to make it work. This is a permanent mod (so you better get it right the first time), and the hole can leak light and fumes.

This part acts as a ‘spacer’ between the lid and chassis of an Anycubic Photon Mono 2 printer, which allows wiring the linked heater without having to modify your lid. Additionally, it has the following benefits:

• Uses existing finding features on the chassis to sit snug, meaning that removing the lid won't also remove the spacer.
• Allows the cable to be managed neatly behind the Z-axis, putting it out of the way when putting in and removing the vat.
• Allows the use of a vat cover (such as this one) without interference.
• Has finding tabs on three of the sides, ensuring proper lid alignment without leakage, while also making the lid easy to remove when needed.
• Is decorated on the front with cats, for both convenience and aesthetics.

How to print this

This print is large and requires a bed with at least 230mm in both X and Y (but more is definitely better). If you have a smaller printer, you can cut it into quarters and glue it together afterwards, but this will definitely not be as strong (plus, see notes on which material you should use). 

Given that this part is going to be in an environment where exposure to uncured resin is likely (through splashes, drips or leaks), chemical resistance is an important consideration. This rules out PLA as a material: do not print this out of PLA! Good material choices (according to this article) are PETG, ASA or PC. Each of these have different advantages and drawbacks:
 

• PETG is the easiest to print, as it doesn't require an enclosure. It also is one of the easiest materials to print waterproof, which can be an advantage when dealing with resin in liquid form. However, PETG is difficult to glue: if you plan to split this into parts, this is probably the least suitable material. It is also essential that you pick a fairly opaque colour (such as black), as otherwise, you may leak light.
• ASA has good UV resistance, which is a minor advantage, as a resin printer's screen emits strong UV, although it really doesn't matter much. It can also be acetone welded, which will fuse the parts directly, making ASA the best choice if you plan to cut up the print for a smaller print bed. However, ASA has the worst layer adhesion of all these materials, and needs to be printed enclosed for best effect: without doing this, setting aside health issues, the finding tabs can break off after some time.
• PC has the best chemical resistance of materials you can easily print in a domestic setting. However, it needs to be enclosed for best effect, and can be a bit brittle, which given how the part mounts, may cause cracking due to fatigue. It is also by far the most expensive option, and like PETG, you should pick an opaque colour, as PC can also be quite translucent.

In terms of print settings, this part was tested with a 0.4mm nozzle, and 0.2mm layer height. You can probably use a 0.6mm (or even a 0.8mm) nozzle, but keep layer height to at most half your nozzle diameter, as otherwise, you will lose layer adhesion, weakening the finding tabs and possibly causing them to snap. Use a minimum of 3 perimeters, and 4 is better. 30% infill should be sufficient.

How to fit this

1. Take off the lid from your printer.
2. Place the heater where you want it to be: the optimal location is to the left side of the Z axis (viewed from the front), and guide the cable behind the Z axis. 
3. Place the part around the vat, axis and heater, with the cats facing towards you. Snap it around the white finding studs on the surface, ensuring the cable from the heater runs through the hole on the right-hand side.
4. Put on your vat cover if you're using it.
5. Put the lid on top, ensuring that the side finding tabs are on the inside, while the back tab is on the outside, of the lid.
6. Enjoy!

The included pictures show what you can expect to see.

What's included

We provide an STL file and a STEP file, as well as the original FreeCAD source used to make this (as per its GPL license requirements). 

About the cats

They're the best, uwu.