Attaching a spring perpendicular to a 2x4

[dborns]

I get that this is way out of the realm of home improvement, but I've always had great advice and help here and thought I'd give this a try. I'm going to work on a small project for my gym, and have looked at different standalone boxing equipment. What I'm wanting to do is take a 2x4 in a bucket and attach long springs perpendicular to it at different levels for punching. I'll cover the springs with a plastic sleeve and the sleeves with pieces of pool noodle. I want the springs so that the "arms" will come back to the same position. I'm trying to figure out a way to attach the springs to the face of a 2x4 so that they are completely secure and won't loosen and come flying off. I'll attach a picture to hopefully explain my idea better. Thanks in advance for the odd question.

 

[Snoonyb]

Were it I, and it isn't, I think I'd use a combination of garage door springs, like these; https://www.homedepot.com/b/Doors-Windows-Garage-Door-Accessories-Garage-Door-Springs/N-5yc1vZbnqt

Say a #1 or 2 for the vertical and a couple of #7's for the outriggers.

 

[dborns]

Were it I, and it isn't, I think I'd use a combination of garage door springs, like these; https://www.homedepot.com/b/Doors-Windows-Garage-Door-Accessories-Garage-Door-Springs/N-5yc1vZbnqt

Say a #1 or 2 for the vertical and a couple of #7's for the outriggers.

Yeah I haven't looked into springs much, I just had noticed a couple on the clearance shelf at HD, and those were about 1"in diameter. The size and length of the springs will be something I will decide on when I put together a material list. I'm a little wary about garage springs though. I do need something with some weight and strength so that they don't start sagging, but I'm thinking of one of those swinging back into place with my face in the way.... That maybe the way to go though if I can find some that are for lighter doors and won't take my nose off.
I drew a quick diagram of my initial plan on how to put this together. Just a vertical 2x4, (or 4x4 if I think I need more "meat"), embeded in a bucket with holes drilled through at different levels for the "arms". I just can't think of a safe and secure way for the spring to be connected to the wood. I thought maybe the bolt passing into the end of the spring and a washer on the end of it that is bigger in diameter that the spring then a nut to tighten it down? My ideas always seem to sound good until I actually try them so I'm looking for any other suggestions.

 

[Snoonyb]

I was thinking of a 36", #7 center bracketed to the 2X, or more likely a 4X4 which would leave about 14" extension, and a piece of 3/8" or 5/8" rebar would act as a stiffener. But also, the recoil would be an incentive in improving your ducking skills.

There are also leafs from a leaf spring.

Some local garage door repair facility may also have springs, from replacements, they would be inclined to part with.

 

[bud16415]

Use a 4x4 and drill holes to a good fit for the springs OD about 3/4 of the way thru. install the springs with epoxy glue.