filament winder with belts

I looked at several Filament Spool Rewinders online, but none of them really satisfied me. There were several reasons:

• On almost all of them, the drive shaft breaks because it is printed
• many winders do not use ball bearings
• almost all winders rely on gear transmissions that sometimes do not run properly

That's why I modeled and printed the winder myself

Instead of gears, I use GT2 timing belts. The Bambu Lab spool has an inner width of approx 57mm, subtracting 1x filament diameter leaves approx 55mm winding width. For 1.75mm filament, this is about 32 layers side by side in the spool. The timing belts translate the winding roller from 32 revolutions to 2 revolutions on the threaded rod, which moves the filament guide by 55mm. The timing belts can be tensioned via the middle timing belt pulley. "Long" screws must be made from two M5 threaded rods and M5 lock nuts (glue them)

Instead of printed axles, I use M8 threaded rods. The parts on the drive axle with the spool can be fixed to the threaded rod using lock nuts or radial set screws/screws

I have fixed a 40mm diameter spool holder on the threaded rod. For the Bambu Lab spool, I modeled an adapter and a clamping lid that aligns the spool for the movement of the filament guide. Other spools can also be mounted via adapters as needed

The spindle of the filament guide is attached to the last pulley with screws, so an alternative spindle can be mounted if necessary

The pin that runs in the spindle is "pressed" by a compression spring and can also be easily replaced if required

The spool is cantilevered; if necessary, a "support" brace can be mounted at the free end

In the video, you can see the adjustable filament unroller in the background, with which I can also unwind 2.5kg spools

https://makerworld.com/en/models/772498#profileId-708554

Below are pictures showing the assembly order and some links to purchased parts:

• Belt profile GT2, width 6mm, closed length 320mm (not by the meter but finished endless belts; originally there was an Amazon link to the correct belt here, but now the seller under that link offers belts by the meter)
• M3 threaded inserts https://www.ruthex.de/collections/gewindeeinsatze/products/ruthex-gewindeeinsatz-m3-100-stuck-rx-m3x5-7-messing-gewindebuchsen
• Ball bearings 608-ZZ https://www.amazon.de/HonLena-Kugellager-Shielded-Rillenkugellager-Skateboard/dp/B08K936Y1Z?dib=eyJ2IjoiMSJ9.4Y0N3ydjOET7CARpjzSDyKdi0wFVWM-KG_P-LbjEcTfJCJKtxoOegL0qHcZ6SZ3MkxVWaIivuQdWlP9R8MiUv5ynootFWRmjqKNTsUC496wuMkRYgP8ShyvjybTr8BImkV4pb9IODtF6eTKbCRbmQVIoJqoxL-C7eDpv0tPqxYK_kjtTIFZxuU0fnJiQyjipdWGeKUTOokkVowqwvBCjrsItieGaz5e5xhTdSqBiHwmtIIaw4K8enEWjFzyVwRzTU4hAaglvOYfhmceaGi35VorBc6UpLpByNpw9QpULyOs.C1M_8eQ90IBM2U0Uf1fCvyf69qiklxdLQ1dVhrB79eg&dib_tag=se&keywords=kugellager+608-zz&nsdOptOutParam=true&qid=1731591954&sr=8-5
• Screws, nuts, washers, threaded rods: Links don't make sense in my opinion; just use what you have or buy from your preferred hardware store / Amazon
• I had the compression spring lying around; here too, use what you have or experiment

Pulley1 Assembly

Pulley3 Assembly

Pulley2 Assembly

Spool Holder Assembly

Install Spool Holder Assembly in Base

Install Pulley2 Assembly in Base

Install Pulley3 Assembly in Base

Install Spool

Tension Belt