Mainspring Replacement

[Scoutmaster]

I just replaced my recoil spring with a 16 1/2# variable rate from Wolf. It came with a new mainspring, but before I pull the retaining pin and send the old spring across the room, I thought it might be prudent to ask how to get the new spring back in? I looked on a few suppliers sites and didn't see a tool that compresses the spring. Is there a trick to replacing it?
Thanks,
Don

[Joni Lynn]

Sounds like this is your first time replacing one. Wear safety glasses. I clamp my housing in a padded vice and press the spring straight in with a large punch.

[nunya]

I just held the MSH in my left hand, slid the mainspring housing pin retainer in, slid the mainspring in, put the mainspring cap in the spring, then used a punch to compress the spring. Then I had my wife drop in the mainspring cap pin. It was really easy.

[Hawkmoon]

Before you go tearing your pistola apart, are you certain it came with a replacement MAIN spring? Wolff recoil springs usually ship with a replacement firing pin spring ...

[Scoutmaster]

Before you go tearing your pistola apart, are you certain it came with a replacement MAIN spring? Wolff recoil springs usually ship with a replacement firing pin spring ...

Your correct the smaller spring that came with the Wolff recoil spring is a firing pin spring! My mistake. The mainspring had come with a Ed Brown frame rebuild kit.
Don

[Scoutmaster]

So basically I guess there's no trick other than common sense and muscle. I was afraid of that. LOL
Thanks so much for the help and sharing the benefit of your experience! There's no substitute for experience.
Don

[nunya]

One of the more prolific posters here posted a picture of a tool he made for this task. Basically he mounted a punch vertically in a piece of wood. I can't find it now. It would free up your 2 hands - one to press down compressing the spring, and the other to insert the cap pin. Either way, you need 3 hands. As we only come from the factory with 2, the 3rd can be a vice, a mounted punch, or your unsuspecting wife. ;)

[Hawkmoon]

I use a 3" C-clamp I bought at one of those liquidation stores. Cost me about 79 cents. I ground the floppy flat part off the threaded portion and took the diameter of the remaining ball down to a shank small enough to fit inside a MSH, then I filed a shallow groove in the flat portion of the C frame itself, to retain the bottom of the MSH. Makes it easy to turn the screw and depress the plunger just enough to release the cap pin, then unscrew it slowly to release tension of the spring.

Probably took me longer to type that than it took to actually modify the C-clamp.

[ram350002]

I read a post (not sure who's, don't want to steal their thunder) earlier that works like a charm.
Clamp a punch (spring pin punch of approx same diameter works best, or one with a some what rounded tip, it's easier on the contour of the cap) horizontally into a bench vise, then push the Main spring cap/housing onto the punch with the pin facing down. Once the spring tension is removed from the pin it usually falls right out. Hold your free hand under it or position everything over your bench so you don't lose the pin, it's a bear to find on the floor. Once the pin is out, SLOWLY let the spring extend until all the pressure is relieved and replace. If the pin doesn't fall out, you still have a free hand to press it out. Assembly is just the reverse only leave the retaining pin hole facing up and drop it in once the spring is compressed.
It was the first MS I ever did and it was remarkably easy this way. It gives much greater control over the whole process and it doesn't take that much force to compress the spring using this technique. One hand is all that's needed and it leaves a free hand for the pin.
You didn't hear it from me first, but it sure works. Beats chasing down flying parts but I still recommend the safety glasses in case something slips.

[wichaka]

I put a pin punch pointing up, in a vice. Put the msh housing over that and push down. Then with a very small pin punch, push out the cap pin enough to grab onto it with your fingers. Then slowly release the works.

[Scoutmaster]

I put a pin punch pointing up, in a vice. Put the msh housing over that and push down. Then with a very small pin punch, push out the cap pin enough to grab onto it with your fingers. Then slowly release the works.

I tried this method today and it worked like a charm. There was a lot les tension than I thought and it eased out just fine.
Obviously the mainspring has not seen the light of day in the last 48 years. There was rust and black gunk in there with it...AND it still worked fine. I am however glad that I got it out to change. I have the new spring and new mainspring cap and mainspring housing pin retainer so I guess it's good for another 48 years. LOL
Thanks to everyone for your help and suggestions.
Don