EIBOS Cyclopes Riser - Bulkhead, Shielded, Insulated

I also observed the disappointing flaw with the EIBOS Cyclopes (not cyclops. In my head I pronounce it as “sigh-clop-ees”) filament dryer. The heating element and fan are way too close to the filament spool and normal operation causes deformation or fusing of spool loops with PLA. So, I designed this upgrade to make use of two common types of projects for this dryer:

1. Risers to lift the filament spools so they aren't immediately above the heater vent
2. Heat shield to block the super hot air from blasting the filament directly

Attribution

I'll follow suit with Pete R. and attribute the projects who inspired me:

• Pete R: Extension Walls and Bearing Risers. Pete's concept for integrating the outer four bearing races with the riser (extension) shell was clean. I definitely nabbed that concept.
• MMartinJ: Easy Access & Filament Change. MMartin may have been the first to design the riser shell? This inspired Pete's.
• Eef: PCB Heat Shield. Eef posted images of using perf board (FR4 fiberglass) for the heat shield. This is great because that material is plenty capable of handling super high temps.

Safety Concern: Plastic Heat Shields

Generally, I've been concerned with other projects with heat shields…

• Firestarter Mk1. 
• Firestarter Mk2. A user in the comments said it melted even printed with ASA. That vent is HOT.

These shields block airflow. I absolutely cannot endorse a project that recommends placing plastic directly over the dryer vent. The creators were responsible enough to warn users against low-temp plastic for printing the shield. However, I still consider this wildly unsafe:

These low profile heat shields may reduce airflow, worsening the hot-spot on the heat shield, and could cause heat creep into the fan or electronics compartment.

Heat Shield

So, my project aimed to be much safer with the use of G10 (quite similar to FR4) for the heat shield mounted 100mm above the vent. I scored the sheet with a plank of wood as a straight edge for a box cutter. Dozens of passes on both sides and it snaps cleanly.

Heat shield is 80mm x 180mm. Mounting hole is designed for a ¼" screw.

Thermal Sensor Placement

This project rises the thermal sensor by 100mm. This preserves the relationship and orientation between the thermal sensor and the filament spools. Cyclopes designed and tuned this dryer with the sensor placed here. Relocating the sensor may affect performance.

This project uses a small clip to retain the thermal sensor and keep it from falling down. See the images (it's a little white PLA slotted square).

Internal PTFE Tubing

The internal tubing serves several crucial purposes:

1. It protects the filament from direct hot air as it is fed through the tubing fitting to the printer. I observed the filament kinking on retracts with the filament out in the open.

2. It protects the filament from sliding along a potentially jagged G10 heat shield snapped edge.

Insulating Foam?

Adding 100mm of risers increases the surface area for heat to escape through. This means the heater would need to work harder maintain the same temperature as an unmodified Cyclopes dryer. The heater was likely designed with headroom to accommodate operating in cold rooms. But, I'd recommend against adding to a dryer's heat dissipating surface area all willy nilly. EIBOS designed this dryer with the base unit's dimensions in mind.

I installed foam in the controls compartment, on the outside of the risers, and on the outside of the lid.

Please do not install foam insulation inside of your dryer's filament compartment. Most foam isn't designed to handle 90°C or higher which this heater vent can easily put out.

Assembly

Main Riser and Heat Shield

1. Pull the thermal sensor up and out. It's held in with friction- just pull it out. Be slow and careful; you only have a bit more than 100mm of additional length.

2. Feed the thermal sensor through the underside of the "bearing stand double riser".

3. Install the “thermal sensor retaining clip” by twisting the thermal sensor so the two-wire cable can slot into the clip.

4. Seat the clip into the riser, press the thermal sensor down so the black sensor tube is resting on the clip, and hit the area with a dab of hot glue.

5. Seat the bearing stand outer riser.

6. Install the bulkhead tubing fittings.

7. Cut about 8 inches of PTFE tubing (x2) for the internal filament guides. Install by pressing firmly into the fittings.

8. Install the heat shield by fastening with a ¼" screw. I didn't even bother with a nut. The shield is sort of floppy but always sits flat.

Foam Insulation

The heat from the dryer softens the foam adhesive causing it to release from the dryer / riser. You need to use the included trim files or hot glue to keep the foam from peeling off.

You'll have to cut the insulation carefully to make sure it's straight and square. The stuff I linked below isn't exactly cheap so take your time. I used my calipers by locking them at the width desired and dragging the sharp edge on the wax paper backing of the foam to mark where to cut, then used a long flat edge as a guide to cut with a box cutter.

Whether you use the trim or not, I recommend using hot glue to put all of the foam / trim together.

Warning: The foam I linked (and likely any other neoprene foam) melts at hot glue temperatures. Don't think you can clean up any accidental applications of glue. Ask me how I know.

Additional Material

4mm bulkhead tubing fittings

½" closed cell foam