I have increased spring tension by almost the same way. But not with metal, I have taken the spring type clothes pins apart and slid one wooden piece under the spring between the cross plate and the spring arm piece that rest on the cross piece. You have to break off a bit of the narrow wooden end but that did a good job for me = temporary of course........jk
Wood shims actually work great! The springs indent into the wood a bit which keeps the shim from slipping out and holds the shim in place. I have made them on the spot in the field with just my pocket knife. Only disadvantage is that they need to be replaced occasionally as you said.
Am I mistaken, or are you just doing a modification to increase spring strength? Are you sure that the springs are too weak and are different from when you bought them since you say you've always used setters with them. Are you losing animals? I know if the springs were weak on my traps, I'd just replace the springs. 2 years is an awfully short amount of time for a spring to last.
Replacing the springs is preferred. The trouble is, the replacement springs will be just like the ones on the trap unless you can find some old springs from the original CDR. If I could find more of them I would be changing them. Right now I would be surprised if you can find any replacement springs at all.
I wonder when those were made? I purchased one from WCS about a year ago and it seems to be ok.
Do you have some old original CDR’s with MO pans to compare? How a about NY pans? The NY pans have stronger springs than the WCS, but I still shim them to get them to match the MO pan strength. How many beavers have you caught in them? Have you lost any? I have run originals, 2nd gen, and WCS side by side - in numbers and year-round - and until you do that you have no frame of reference.
I did tell WCS. The rep I spoke with definitely listened to what I had to say, and said he would make sure to bring it up. As I understand it, the current owners did not make the last run of traps. Hopefully they will fix it on the next run. It should be a simple fix, since it appears to be an error winding the springs, they were wound a bit “too far”. This is easy to see once you have the springs from all 3 generations removed and sitting side by side. And easy to tell when you try to put those springs back on - if you have the old original CDRs I recommend not removing the springs unless you are prepared to make a special tool to put them back on - and if you have the originals no need to remove them in the first place, just catch beaver with them.
I tried a lot of stuff, some worked some did not. I even “unwound” some of the springs and then re-heat treated them in an industrial oven. In the end, shims work as well as anything and are the simplest fix I have found.
Having tinkered with them all, the WCS version of the CDR is actually my favorite build of them all if it were not for the weaker springs. If WCS can return to the original 1st generation CDR spring strength, I will be begging them to take my money.