IdeaFormer 3D Printer Belt Tensioner X and Y Axis, 2020 Profile X-Axis Belt Tensioner & 2040 Profile Y-Axis Synchronous Stretch Tensioner, Straighten Belt Tensioner for Ender 3(X2020+Y4020)

Function exactly as they should and fairly easy to install

Very fast & easy to install, just a few quick screws to swap brackets. Have adjusted Y side to fully maxed out & belt is *almost* properly tensioned, whereas original bracket offered about 2-3mm of adjustment range.As that means i can only adjust the x tension with this i feel half marks for half-useless product is generous enough.If these brackets could place the idler wheels where the factory originals did i wouldn't hesitate to purchase more for my other printers.

These things are simple to install and can tighten the belts on an ender 3 way better than the stock can. This was one of the first upgrades I have done and I would always recommend this. With the stock ends you just cant get them tight enough and this fixxes that.

This is listed as working with the Ender 3. Not the Ender 3 Pro, or the Ender S1, etc. The "Ender 3".It does - sort of. More like it can be made to. The cutaway part to make room for the bed wheels isn't cut away far enough, and even when the part is moved as far away from the extrusion as possible to still have all the screws inside the extrusion, you'll lose at least ~5mm of build space in that direction because the bed will hit the cutaway part of this piece and not be able to travel further.This can be mitigated by only putting the two screws closest to the bed in the extrusion, and leaving out the two closest to the dial on this piece. This provides a less-than-ideal mounting solution, but it will allow the piece to be mounted far enough off of the extrusion that the bed can once again reach its full range of travel.Unfortunately, the screw on the included dial is then not long enough to reach the adjustment wheel, meaning you have to either pick between a non-adjustable belt system or give up at least ~5mm of build space in the Y direction.Giving two stars instead of just one, because if you can find a long enough (but not TOO long) M5 screw it can be made to work with the Original Ender 3, even if there will only be two screws securing it to the extrusion.

After initial installation Y axis lost about 10mm. And moving bed to 235 position (fully forward) bumping into tensioner. Motor skids with noise and become not synchronized with coordinates anymore.Well, solution would be moving tensioner forward as much as possible that front T-nuts are almost out. This adds 5mm. Remaining 5mm can be gained back only by filing bracket and removing metal as shown on pictures. As you can see wheels almost touching it at 235mm position.I tried to mount tensioner with only one pair of T-nuts but it didn’t work because not enough length of belt.Overall good for the price. But requires some work.

It takes up about 10mm of Y travel.

Can be easily disassembled and reversed as needed. Would love to see a 90-degree attached arm version of these.

It works great