The GT2 Y belt of a 3D printer needs to be both taut, and secured to the hot bed plate. There are a number of ways to achieve this, including:
- Standalone tensioners;
- Y-axis idlers with built in tensioners, and;
- Tensioners which also secure the belt to the hot bed plate.
Here is a selection of tensioners that can be employed:
This spring only provides tension, and does not secure the belt to the plate. From 10PCS Timing Belt Tensioner RepRap Spring 3D Printer Ultimaker MendelMax Pr, £1.07, or cheaper still, 10pcs GT2 Timing Belt Locking Torsion Spring for 2GT 6mm Width Belt 3D Printer, for £1.00.
This is how it is used
This printed part only provides tension, but does not secure the belt to the plate. From Timing Belt Tensioner 3D Printed – 6mm – RepRap – CNC – 3D Printer, £1.49
This is how it is used
Aluminium Belt holder
This belt holder, secures the Y belt to the heat bed plate, and can also be used to tighten the belt. From Aluminum Gear Fixed Holder Backet 9*40mm for 2GT Timing Belt 3D Printer Reprap, £2.19, or, even cheaper, Aluminum Gear Fixed Holder Backet 9*40mm for 2GT Timing Belt 3D Printer Reprap, for £1.99
However, do not be tempted by its low price. There are a few mechanical issues with this belt holder:
- There is only one screw – when compared to other holders where there are two, or more, thus securing the belt, or ends of the belt more tightly, evenly and safely.
- There is only one screw – This one screw will both secure the belt and attach the holder (and belt) to the y plate at the same time.
- There is only one screw – yet again. You will have to secure both ends of the belt at the same time, a tricky operation securing one at a time, let alone both simultaneously
- There is only one part – although it can not be used alone, as the teeth of just the holder can not be used to hold the belt in position, as the teeth of the belt will face towards the plate, and not away from the plate. In other words, the holder needs to be mounted with its teeth facing away from the plate, which leads to the next point…
- There is only one part, meaning an additional part, i.e. a large washer, or plate of the same shape as the holder, needs to pressed up against the rear side of the belt, thus pushing, and holding, the teeth of the belt into the teeth of the holder, like so
Aluminium Belt holder/tensioner
This more elegant belt holder, as above, secures the Y belt to the heat bed plate, and can also be used to tighten the belt. From Prusa i3 Reprap Mendel All Metal Aluminum Alloy Y Axis Timing Belt Tensioner, £16.99
There are many other variations, and innovative mechanisms. For example, from Prusa i3 Adjustable Y-belt Tensioner & Holder
or a simple use of an elastic band, or cable ties, from Simple Y tensioner
The short video Automatic Belt Tensioner U-Design for RepRap Prusa Mendel, sows a nice design
See also P3Steel version 4 modifications.
As the P3Steel Y axis end plate does not have the fixings for the typical Y idler cum tensioner, a different approach is required.
There is the superlative Y idler, which does not provide an adjustable tensioner (which is, instead, in the Y-belt holder (see below)), unlike the Wilson and Prusa i3, from Toolsen, from P3steel 2.x – Y-axis idler:
The tensioner and Y-belt holder, from Toolsen, from P3steel 2.x – Y-axis belt tensioner:
Similar to the Toolsen design, there is the Puttelino Y belt holder and tensioner, from P3 steel, Y-axis belt tensioner
Also, there is the Y belt tensioner, which fits around the Y idler and comes in four parts, but it requires additional drilling of the Y end plate, by Kwendenarmo, from P3Steel Y belt tensioner (v1)
Also worthy of note – there is the more traditional P3Steel – Adjustable X & Y belt tensioners by Outcastrc (although it is not clear from the photos how the Y idler works or is mounted) and the P3Steel Y belt tensioner (v1), which is similar to Kwendenarmo’s, by ok1cdj.