Sunlu FilaDryer S4 bearing roller

I bought a Sunlu FilaDryer S4 and it came with a missing bearing roller. Their support promised me to resend it (they lied, it didn't arrive in 4+ months) and ignored my messages when i asked about the package; they finally answered when i said i want to buy the roller and then lied again that spare parts are available on Amazon.

Well screw them, i'll make my own!

The DIY version looks the same (except the silver strip in the middle) and feels the same.

You'll need:

• around 80mm of black silicone tube; 6mm inner diameter, 8mm outer diameter ( https://www.aliexpress.com/item/1005004444889203.html )
• 85-86mm long 2.5mm stainless steel rod ( https://www.aliexpress.com/item/1005003594895025.html )
• 2x 604ZZ bearings ( https://www.aliexpress.com/item/1005002932533525.html )
• lots of patience for reprinting because the bearings, tube and rod have bad tolerances
• a rotary tool or angle grinder to cut the steel rod to the right size

Print instructions:

• print two of them with PETG
• use brim
• random seam position
• external perimeters first
• supports on build plate only

Assembly instructions:

1. Stick each printed part on the steel rod; if it doesn't fit, try to clean the hole with a 2.5mm drill bit and if that doesn't help, reprint the part a little larger
2. Put the silicone tube over the whole thing
3. Press one bearing on each side

Because the cheap parts i linked have bad tolerances, be prepared to reprint it many times. Unlock the slicer's scale factor and resize both X and Y at the same time in 0.1 increments until you get a good fit with all three. If it maybe helps - mine was perfect at 6.4mm (106.67%).

FAQ:

Q: Why not just use a 4mm steel rod and call it a day?

A: It's easier to cut a 2.5mm rod and press the bearings on plastic than on a 4mm rod, especially if you don't have the right tools.

 

Q: Why print two halves instead of just one part?

A: It's easier to stick both on the rod than just one. I also had issues with the dimensions of the top bearing mount when trying to print it as one part; i guess PETG didn't have enough time to solidify despite slowing down the printing speed.

 

Q: Why PETG? The air exiting the dryer's fan is hotter than 80°C when PETG starts to soften!

A: The DIY roller is meant to be used on the furthest away position from the fan where it isn't so hot anymore. Feel free to print it with ABS, ASA or any high temperature filament if you want.