CYMA CM357 (M870) SIG 550 MAG ADAPTER V1

SIG 550/ 551/ 552 mag adapter for cyma CM 357

I did not have any issues with assembly.

latch assembly requires M2.5 machine screw (linked below)

Pin hole in the latch should be slightly larger so latch moves freely

Requires torsion spring You can use two different springs depending on preference of how much resistance you want.

BC006 https://uk.store.bambulab.com/products/torsion-spring?id=42010411991100 ( I'm using this one)

or

BC001 https://uk.store.bambulab.com/products/torsion-spring?id=41313805566012 This is stronger spring and needs to be cut down by approx. 5mm on each side as it is too long.

To assemble:

1. You need to start from preparing spring. one spring leg need to be bent slightly so the edge can move smoothly and does not catch on the housing - see image, I've bent approx 4-5mm from the top, approx 10-20 degree angle

2. Insert straight leg of the spring in to the hole in the latch. position the latch in the housing. Put in the screw. DO NOT install the wedge in the housing prior to this. if you do you will be working the spring under tension which can be difficult.

4. Once you have the screw in, push in the latch so it is completely hidden in the housing, and insert the wedge from the top. it should be fairly tight but if not jus use some glue or shim one side.