Q on Spring steel

[Trysop]

Hello All,

I am in the process of trying to build a SCA helmet and I want to put on a spring pin to hold the visor in place, the pin will lock a Brian Price visor hinge onto a L hook by depressing when the hinge is sliding down with the pin popping though the hole when in place to hold it on). It is a shameless attempt to copy this very cool idea by Klaus Rother, hope you don't mind :

see here: http://gildedboar.com/klappvisier/id4.html

Before I ruin the few bits of Spring steel I have, I hoped that someone with more experience in spring could offer some advice. I have both a flat pieces of bar about 1 to 1.5mm thick and round stock spring steel (about 4 mm) from old gin traps. I was planning on annealinng it out, so I could straighten it, flatten it etc and clean up the bad rust to remove as much damage as I could (like the bad pitting form the rust) to get it to a usable state, make up the desired piece, retemper etc and mount.

However I have no idea how long the spring needs to be, how thick it should be etc etc, I appreciate that the thinner I make the spring the shorter it can be, but the thinner it is the more likly it is to not keep its shape, Right?? Will a dent/pit in a bit of spring act as a weak point and will it break there when it fatigues??

I am trying to avoid as much experimentation as I can by getting any input you fellas can offer to head me in the right direction. What makes a good spring pin for a SCA helm?, what have any of you learned works well etc etc.

If I have missed something obvious please point it out, my knowlegde of spring it pretty scant at best.

Thanks for your help in advance.

Trysop

[Kenwrec Wulfe]

Trysop,

Generally when I have made spring pins, I use old hacksaw blades that have had the teeth ground off, BUT when those are not handy, I use 20ga 1050 spring. For most spring pin setups, I make the spring part of the spring pin about 2 1/2 - 3 1/2 inches long, though it really depends on several factors as to how long is practical.

[Thomas Powers]

Heavy lumber or steel banding material, no heat treat needed yet can still be cut with shears.

Thomas

[Trysop]

Hi Guys,

Thank you for the input, saw blades had not occured to me as a source of Spring steel and using one might be far easier then trying to make the bits if spring I have usable, they are pretty nasty, and saw blade are far easier to get.

I take it when working the blades to drill holes and remove the teeth, slow and cool is the way to proceed with regular cooling so as not to ruin the temper?? and can they be cut in a shear without shattering, ot would a chisle blow to "break" it in the right place work better?

Thank you for the responses, sorry it only generates more Q's

best wishes

Trysop

[Tarquin Bjornsson]

tempering and whatnot is a pain in the a$$. i would use an old hacksaw blade about a 1.5 inch length of it should be fine.

[Thomas Powers]

Cheap hacksaw blades can be quite brittle. I would suggest a section of bandsaw blade instead they are designed to flex, you can cut them from the back with bullnosed hand shears (I make billets for pattern welding from them and so have cut a *lot* of them this way) let the last little bit with the teeth break rather than shear and grind off the teeth and you can then work the steel with care.

Thomas