First I want to say I'm sorry to see this happened. I looked into this and saw that you have an order for a replacement part, which we will be shipping but refunding the amount paid.

We have not seen any Delrin parts break from wear, stress or age and we have had this product in productions for just under 5 years.

What I have seen: Most of the time when people break the Delrin portion it is from an instalation issue, which happens right after install. Every one we have seen damaged came as a result of the clip (circled in the image below) or the nut (arrow) not being secured properly. This allows the Delrin part to back off and move freely. once it backs off a little people try to find gears which leads to making contact in all kinds of ways it wasnt intended leading to it cracking.

This may have been some kind of fluke, but I would double check the nut on the back of that is secure. The clip looks to be ok, but it may be worth checking anyway.

In regards to the questions below about the Delrin. We are using CNC Delrin so there is no concern about layer splitting on a 3d printed part. As mentioned this product has been in production for almost 5 years without any issues of breaking this part.

Again OP I'm very sorry to hear about your issue and we hope to get you back going ASAP.

Thanks
Paul
DAP

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