What size tortoise wheel?

[The_Four_Toed_Edward]

I am considering getting Edward a tortoise wheel, but I worry about the dimensions as I worry that a wheel that is too small could be unhealthy as far as walking posture goes.

What size would you recommend/are using? (wheel diameter and the walking depth)

I am prepared to DIY since the biggest ones that I have found thus far have a diameter of 40 cm and a walking depth of 16 cm (they are made for hedgehogs).

 

[The_Four_Toed_Edward]

Edwards SCL is about 11 cm (4.331 inches), the width of his shell is 10 cm (3.937 inches) and the width of his stride measures about 13 cm (5.118 inches). He weighs about 500 grams.

If I go the DIY route I plan on lining the wheel with some cork fabric I already have and using a large barrel/bucket of some sort for the wheel itself, as I have found instructions for constructing a wheel for hedgehogs.

My question is, what kind of plastic is safe? I have been looking at three different types:

1. 80-liter bucket. Diameter: 50 cm (19.685 inches) Material: recycled polypropylene.
2. Round construction bucket, 90 liters. Diameter: 62 cm (24.409 inches), Material: Made from LPDE plastic (polyethylene) derived from recycled plastic
3. Round mortar tub, 90 liters. Diameter: 65 cm (25,590 inches), Material: polypropylene recycling

The first one might be too small, but it says that it is for both indoor and outdoor use and can stand up to temps up to 65 C (149 F). which would totally be in the safe zone I guess. My worry is the combined effect of the UVB and the heat lamp wearing down the plastic.