On an FDM machine the window only has to survive heat. On a resin machine it also has to survive the resin. Choose wrong and the first distorts, while the second hazes over and cracks within months — two completely different failures from the same drawing.
Repairs on these parts cluster in four places.
Resin wicks into micro-scratches and cures there, leaving a film that will not wipe off — this is not a cleaning problem. That position needs polycarbonate, or a window built as a replaceable pane on a quarterly cycle. Swapping a pane is far cheaper than stripping the chamber.
In a 50–60 °C chamber the difference in expansion between acrylic and an aluminium frame pushes the door open. Leave 2 mm of movement all round and use a soft gasket — clamp the panel rigidly and it will leak as soon as the chamber comes up to temperature.
Above 600 mm the hinge side drops under sustained load, and the gap along the bottom edge grows. A vertical stiffener or a top-slide arrangement works better than extra thickness, and weighs less.
In a dry room the charge is enough to hold a dust layer that comes back two days after wiping. Anti-static sheet fixes it, but the layer is removed by alcohol — neutral cleaner only.
Whole-machine parts and pilot batches both run in-house, including UV printing and screen printing. Process detail sits on the Prototypes & 3D printing page.
A printer enclosure is a series of small thermal and chemical problems in one box. Getting it right is a matter of treating each face for its own job rather than specifying one sheet for everything.
A front door is the largest moving panel and the one that fails first. Above roughly 400 mm wide it needs a full-width piano hinge rather than two butt hinges, because two hinges put the whole weight on four screw holes and the panel cracks between them. The door also needs a stay or a gas strut — a 500 mm door that swings shut on its own will eventually be dropped, and a dropped acrylic door chips at the corner. Thickness: 5 mm up to 400 mm, 6–8 mm above.
Chamber temperature decides both material and air gap. An FDM chamber at 50–60 degrees C is comfortable for cast acrylic provided the panel has 25–30 mm of air gap from the bed and is not clamped rigid on all four sides. Above 70 degrees C, acrylic creeps rather than melting: the panel bows toward the heat and holes go oval over weeks. At that point the honest answer is polycarbonate, which handles 100 degrees C and above without the same creep.
Resin printers are a chemical problem before they are a thermal one. Vat splash plus IPA wipe plus repeated cleaning hazes a panel from the inside, and no coating survives that indefinitely. The practical construction is a replaceable 3 mm pane in a machined frame: the pane is a consumable, replaced every 6–18 months, and the frame stays on the machine. Specifying a bonded window instead means replacing the whole panel when it hazes.
| Face | Sheet | Detail that decides life |
|---|---|---|
| Front door, FDM | 5–8 mm cast | Full-width piano hinge; stay or strut; 5 mm corner radius |
| Side and top panels | 5 mm cast | Slotted fixings so thermal movement does not crack the hole |
| Resin vat window | 3 mm cast, replaceable | Machined frame with a gasket land, not a bonded pane |
| Heated chamber divider | 8–10 mm, or polycarbonate | Air gap and free edges where the chamber exceeds 70 degrees C |
| Spool cover or dust cover | 3 mm cast | Rebated location so it does not slide against the frame |
Static is the detail most often left out. A dry printer chamber generates charge, and a standard acrylic window will pull filament dust onto its inside face within days. Where that matters, an anti-static grade or a grounded frame solves it; where the printer sits in a clean room, plain sheet is fine and cheaper.
Enclosures are a volume product, so the cost conversation is different from a one-off machine guard. On a 100-unit run: sheet 25–35 percent, cutting and machining 25–35 percent, edge work 10–15 percent, hardware (hinges, struts, gaskets) 10–20 percent, packing 8–12 percent. Hardware is the item buyers forget, and a full-width piano hinge plus a gas strut can be 10 percent of the price on its own.
Three design decisions move the number most. Making the door and the side panels the same thickness lets them be cut from one sheet nest, which is usually 8–12 percent cheaper than mixing thicknesses. Using a standard hinge length instead of a custom one avoids a tooling charge. And keeping the panel count low — a five-sided box instead of a six-piece frame — reduces both machining and assembly.
Where we push back is on the replaceable window. Buyers often want to bond the resin-machine pane into the frame to save the gasket and the machined rebate, which saves perhaps 6 percent on the unit and turns a consumable into a full panel replacement. Over the life of the machine that is a bad trade, and we will say so once and then build what is asked.
| Item | What we need | Why it changes the price |
|---|---|---|
| Chamber temperature | Measured air temperature at the panel, not the nozzle | Above 70 degrees C the material answer changes to polycarbonate |
| Process type | FDM, resin, or both | Resin machines need a replaceable pane; FDM does not |
| Door size and use | Width, and how many times a day it opens | Above 400 mm needs a piano hinge; daily use needs a stay |
| Cleaning | IPA wipe, or dry only | Determines whether a coating is worth specifying |
| Volume | Units per year, and whether the design is fixed | Above 100 units, standardising thicknesses across parts saves 8–12 % |
For a machine already in production, send the frame drawing or a photo with three measurements. For a new design, send the intended chamber temperature first — that one number decides more of the specification than the drawing does.
Recorded by machine model, with separate assembly notes for replaceable panes.
Polycarbonate or tempered glass first; acrylic only as a replaceable pane. Photopolymer resin that wicks into acrylic micro-scratches cures under UV and leaves a film that cannot be wiped off — that is the material, not the cleaning routine. Built as a swap-in pane on a quarterly cycle, it costs far less than dismantling the chamber.
3 mm on a small desktop machine, 5 mm mid-size, and 5–8 mm with a frame above 600 mm width. Chamber temperature and door span set the answer, not the external footprint — a 400 mm door on a 60 °C chamber needs one band thicker than the same door at room temperature.
Yes, heat bending handles radii from R100 up, with angle held to ±1°. A curved part cannot be built as a replaceable pane though, so a scratch means replacing the lot. That is why we recommend it for small desktop machines and keep flat panel plus frame for wide-format builds.
Yes. A kit normally contains the panels, bagged hardware to a numbered list, hinges or a piano hinge, gaskets where specified, and a one-page assembly sheet. We dry-build the first kit before dispatch so the hardware list is proven rather than assumed, which is the step that prevents a customer discovering a missing fastener halfway through assembly.
One piece for a prototype, 20 to 50 for an economic run. A door is a single machined panel with a hinge line, so there is no tooling — the setup is the program and the hinge drilling. Above 100 units the price flattens and the hinge supply becomes the constraint rather than the acrylic.
