Torqeedo Blade quality?

[Tim Good]

Take a look at this photo. A blade from my Torqeedo 1103 prop came off without hitting anything.

Looking closely you can see small holes. Do you think the plastic moulding was compromised? I recall seeing a similar thing in case metal.

Thoughts?

 

[KevinV]

From the state of the remaining blade I'm not sure about the "without hitting anything" statement - perhaps "without hitting anything this time". A hairline fracture from a previous bump has perhaps come home to roost.

I think the honeycomb is a normal exponent of the casting/ moulding process, but then I have to admit that I have obviously only seen it on broken parts. Worth asking torqeedo themselves methinks.

The thing's plastic, it looks like it's seen lots of use (or UV?), you've bashed it about a bit, it's now failed. Seems fair enough to me, just get a new one.

 

[harvey38]

If the remaining blade didn't have the dinks on it I think you may have a
case but given it has clearly made contact with something, I'd pay my £99 for a replacement, go boating and remove any bother/stress/mither of trying to prove a point.

 

[Tim Good]

If the remaining blade didn't have the dinks on it I think you may have a
case but given it has clearly made contact with something, I'd pay my £99 for a replacement, go boating and remove any bother/stress/mither of trying to prove a point.

A replacement has been bought 2 months ago. The post wasn’t about “how to get a free replacement” or “let’s prove a point”.

I was merely curious what more experienced people thought of the holes.

 

[sarabande]

Since the propeller is knackered anyway, how about testing the other blade to destruction to see if similar pitting occurs in the moulding ?

Mark the other blade with lines from an indelible pen, then stress the blade until it breaks. If you can video the process to show elastic then plastic deformation and finally fracturing, and if the same pitting is visible, you might have a case to press Torqueedo for "not fit for purpose".


Or you could send the existing buts to Torqueedo, and ask them if they think the moulding is faulty. It happens.

 

[Plum]

Take a look at this photo. A blade from my Torqeedo 1103 prop came off without hitting anything.

Looking closely you can see small holes. Do you think the plastic moulding was compromised? I recall seeing a similar thing in case metal.

Thoughts?

I would not be concerned about those holes, mostly clustered nearer the centre of the blade. The discoloration and the horizontal line close to the top edge in photo 9942 are more worrying as this points to a stress fracture some time before the final complete separation.

 

[barryhall]

I would be more concerned about what appears to be quite a sharp transition between the hub and the blades. This would create a stress raiser at the point at which the blade appears to have initiated a crack.
A larger radius at the junction would have reduced this effect.

 

[Kwik Decision]

A little bit of thread drift, but I strongly recommend replacing the shear pin, which is made from something extremely hard, with a length of 3mm diameter brass. I have a friend with a Torqeedo around 4 yrs old, who is on his second prop, as he hit rocks with the first, and the blade failed (like yours has done) rather than the shear pin. Then this summer, in France, he got the painter round the (new) prop, and this time the shear pin did shear, as it should. The problem was we couldn't get the bit of pin out of the prop shaft - it wouldn't drift out, and it wouldn't drill out, even with a brand new drill bit. In the end I took the shaft into Golden Arrow, and they managed to drift it out, but it took him a while. I then bought some 3 mm brass rod, and cut a number of new shear pins for him. These have been tested, as he got the painter round the prop again (he's a slow learner...). The brass shear pin did it's job, and sheared, and this time it was very easy to push the bit out of the prop shaft with a fine screwdriver, put in a new one, and it was up and running again.