Climbing Grip Balls, 80-180mm

Description:

Set of Grip Balls, sometimes called Cannonball Grips, for climbing training. Sizes 80mm to 180mm. Use a reasonably rated paracord/rope to feed through and tie a knot to secure. The centre hole is 10mm so either thin doubled up paracord like in the images or a single rope can be used, a recess in the base prevents any of the rope from hanging out. I draw a line around the centre with a marker to help with accurately repeating grip position (i.e. stop you from getting a longer hold just because you griped around the base more).

Recommend printing the 100mm size first to get an idea of how big they are in your hand, noting circumference increases ~x3 the increase in diameter so the very quickly get out of hand (pun intended). However the larger ones are good for sloper training but I tried to keep these in line with fitting on the A1-Mini. I will likely update the Project file to include larger models soon.

All models include their size marked on the base, I colour these in with a marker to make them more visible.

Be sure to chalk it up before you use it otherwise it can feel a bit slippery.

NOTE: The 180mm has been scaled to 99.5% to make it compatible with the A1-Mini. This technically makes it 179.1mm, but with 0.5mm fuzzy skin it basically makes up for it.

Material: 

Any reasonably stiff and sturdy material will do, I have used PLA Basic and it has turned out great. ABS/ASA, PETG or even using TPU for a softer surface finish on a multi-material print would work. PLA Matt may provide better friction for grip. Avoid using any GF or CF filaments as they can irritate your skin.

Strength: 

The global settings are for 6 walls 10% infill, which I've had no problems with the 120mm size. The project file has modifications per item as listed below.

80-90mm: 

• 5 walls
• 10% infill

100-120mm:

• 6 walls
• 10% infill

130-150mm:

• 6 walls
• 15% infill

160-180mm:

• 7 walls
• 15% infill

Printing: 

Print time varies greatly between sizes as volume of a sphere increases by a factor of 8 with doubling of diameter. Example below of print times from slicer with material use on an A1-Mini:

80mm:    ~2hrs,      77g

100mm:  ~3.5hrs,   143g

120mm:  ~5.3hrs,   220g

140mm:  ~8hrs,      340g

160mm:  ~11hrs,    503g

180mm:  ~15.5hrs, 645g

Printing time and material may be reduces with gyroid infill but the density would need to be reduces significantly (e.g. 5%) to see improvements, which may affect strength (although has better strength is all directions the significantly reduced infill may not make up for it).

The supports are set with a 0.31mm Top Z offset to deal with the fuzzy skin.