Ithaca Crass mainspring installation

[Thomas Baker]

Does anyone know how to install the V shaped leaf mainsprings in this 12 ga double? They are very stiff and it appears that a special tool is needed to compress it in the cramped space available. Help!!!!!
Tom

[Ruff Hunter]

Compress it in a vise and then grab it with a pair of pointed vice grips to keep it compressed. Wear a face shield in case it slips free and goes flying. You should be able to slip it into place and then release the tension. You will likely need to use a small hammer and a punch to seat it entirely.

[Mike Franzen]

I believe Dixie Gun Works sells a special tool for just this purpose. I bought one a couple years ago. They aren't expensive.

[alcaviglia]

Thomas,

I posted the process to installing the mainsprings into a Lewis model in a thread titled: "New project: Ithaca crass model". You'll find the procedure in detail on page 6 of that thread. The similarities between the Lewis model and Crass model are also touched on in that thread.

Additionally, I posted a (near) complete parts list in a photo album called: "Ithaca Lewis (1901) 12 gauge".

Another thread that could be of some help is one entitled: "New member has a Ithaca Lewis project".

If I can offer any other help, please don't hesitate to ask.

[Thomas Baker]

Thanks. Your description and pictures were very helpful. Once I saw the jist of how to put them in I made a spring compresser out of some angle and threaded rod. It works really neat. I'll post pictures once I get take some.
Tom

[ssgross]

Hi there - new member. I know this is a pretty old thread, but I just started my own ithaca lewis project. I'll start my own thread for it, but since this one comes up with every google search, I'll contribute what I learned for everyone else.
My lewis came with the same v-type springs (without loop at the bottom for the strain screw). I found the best way to install was to install the hammer and its pivot pin (screw) first. Then, place the top of the spring under the hammer where it goes. The spring will be near vertical. With one hand, keep pressure down at the root of the spring to keep it from disengaging the hammer, and with the other hand take a flat screwdriver or wooden dowel, and push the base of the spring to the rear. You only need to compress the base slightly before the hole thing rotates and the base is in its proper position. It only takes thumb pressure then to push the spring low enough to insert a punch or the screw into the locking bar hole to help hold the spring in place.
For the v type spring, use a punch to push down at the root until you can put the strain screw on top of it. With no tension now at the locking bar pin, you can remove it. Install your sear, set the set the sear spring on top, install the locking bar, align the holes, and insert the locking bar pins. Then, put your punch on the tip of the spring root to relieve enough pressure to back out the strain screw. If you have a loop type spring...I imagine the same will work and much easier, only put your strain screw through the spring. I tried the method described above, but it was a bear. The left spring has a recess to capture its bottom, but the right has no such spot and it walks everywhere. That's how I found this much easier way of walking the bottom rear of the spring.
You can now gently lift up on the spring to put the strain screw underneath, but it doesn't do anything at this point. I tried assembling with the main spring under the strain screw. When starts to compress with cocking, this position raises the bottom rear of the spring and usually walks it rearward after a couple cocking cycles until the top slips out from under the hammer. It also feels wrong because there is a lot more effort to break open the action, and the last millimeter or so to get the rim of a round to clear the bridge is a beast. After reading of a few others with a lewis-by-serial with these types of springs, I think they used both types of springs. and these types the strain screw just helps assemble and that's it. I could be wrong, but it's what I got. Cheers.