cracks near upper sheave on isc mini spring block

i have been using my isc mini spring block for the last 5 months mainly for light to medium rigging, or as a redirect. i noticed yesterday when i was inspecting it that possible cracks have formed near the upper sheave on both of the side plates. I am wandering if anyone else has had this happen to them with this specific block or with any blocks for that matter
 

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Those don’t look like new cracks from the picture. It looks like the inside of them have the green anodizing coating which would indicate that they were present after the parts were formed but before finishing in the factory. You might be seeing them only now because a thicker anodizing may have warn off in those areas of higher wear. A friend of mine had an issue with a main sheave bushing, sent it in and I believe they said abuse, which is a load of crap. I’ll have to look at his to see if these deformities are there next time I talk to him.
 
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I would have to agree. It doesn't seem like something that developed with use. The "fracture'' is oriented parallel with the sheave. I'd think that if it was abused it would be perpendicular and close to hole for the bushing or pulley.
I have 2 of those little beauts. We rigged a 20-25' lateral white oak limb about 8'' in dia. What a champ!
yours is the first ''failure" I've heard of. I love my pair so much I had to get the bigger brother. the mini orange one for 3/4'' rope.
The only thing I can think of that may have caused a fracture in yours is if it was dropped from height onto a hard surface but there isn't any other marks to show that.
 
Thank you for bringing this issue to our attention.

If you send me a message with your shipping details I will send you a Returns Form as well as a UPS call tag to have the device shipped back to ISC for inspection to determine the cause of the issue.

I can be contacted at: rich@iscwales.com or 216.276.1581
 
I would have to agree. It doesn't seem like something that developed with use. The "fracture'' is oriented parallel with the sheave. I'd think that if it was abused it would be perpendicular and close to hole for the bushing or pulley.
I have 2 of those little beauts. We rigged a 20-25' lateral white oak limb about 8'' in dia. What a champ!
yours is the first ''failure" I've heard of. I love my pair so much I had to get the bigger brother. the mini orange one for 3/4'' rope.
The only thing I can think of that may have caused a fracture in yours is if it was dropped from height onto a hard surface but there isn't any other marks to show that.
yeah definately havent dropped it, like i said ive only done light to medium rigging and not really shock loading, only using as a high point rigging anchor.....unfortunate because i love the little block, great bit of kit....
 
To me it looks like a manufacturing defect in forging. A wrinkle when the press or hammer smushed the metal, rolled two pieces then squished them on top of each other.
 

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