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davidh
12-30-2008, 08:53 AM
i need to make a couple torsion springs for a old car door handle return. i know i am going to need to experment with the mandrel design required but the real question is can i use a previously made tension spring for the wire i need ?

anneal and pull it thru some straightening dies, make the new ones, temper or heat treat or whatever is required ?

after checking with mcmaster it appears i would need to spend nearly $25 for spring wire that may be far better spent on a bottle of good drinking spirits.

i hate to just experment when i can probably just ask the wizzards on this forum that have done it already.

thanks in advance.

GKman
12-30-2008, 09:23 AM
There's nothing especially springy about spring steel, just high yield strength so it doesn't bend under load. A-36 could be used as a spring under light loading. How about 3' of 1/8" oil hardening (O-1) for $2.29 McMasters 8893K18? Or another diameter that fits your need.

Wizard

Your Old Dog
12-30-2008, 09:36 AM
Brownells gun supplies used to sell a flat stock spring kit. they came in various sizes and all 12" long. might be a more handy then an 100 feet of one size!

Circlip
12-30-2008, 10:05 AM
I think I'd be more inclined to have a look round some scrappers or spring manufacturers for something "Standard". I've been called tight on many occasions for re-using Balsa from crashed model aircraft, MY OWN, not anyone elses, Hmmm, hadn't thought of that.

Regards Ian.

Leaf springs (Used to be on cars and waggons) make good wood chisels if annealed, shaped and rehardened and tempered.

winchman
12-30-2008, 10:10 AM
Get some music wire from the local hobby shop. It comes in lots of sizes at a reasonable price.

Roger

Orrin
12-30-2008, 12:36 PM
Get some music wire from the local hobby shop. It comes in lots of sizes at a reasonable price.

My favorite hobby shop sells music wire in straight three foot lengths for a very reasonable price. I've stocked up on many sizes just to have some on hand in case I need to make a spring.

Orrin

gellfex
12-30-2008, 12:50 PM
My favorite hobby shop sells music wire in straight three foot lengths for a very reasonable price. I've stocked up on many sizes just to have some on hand in case I need to make a spring.
Orrin

Yes, we love K&S engineering! They market mini brass and AL tubes too. If it's flat spring stock you're needing, feeler gauges often work well, and are available in exactly the right thickness.

davidh
12-30-2008, 05:23 PM
i measured .077 D. on a somewhat rusty sample , its 5 or 6 turns with a couple fancy bends on each end. . . when i find my sample again i'll make a run at it and post pictures. (dang thing was lost for nearly a year before it mysteriously appeared) i need to cast a small aluminum parts first.

never thought of the local hobby shop. we have a great one in duluth. trains, trains, trains, then planes by the boxcar load. . . . i think the guy is a lionel 027 super collector. price is no object.


this home shop machine site is great for us trying to make things that you cannot possibly find. some of the damdest things can be done with some thought and help from the group. geeze, its like having a friend in your pocket.

how;s that go,, too old fast, too late smart ?

davidh

gellfex
12-31-2008, 01:50 PM
0.78 is a standard K&S size, they should have it at the hobby shop. I use a Duo-Mite bender for jobs like this, they're real handy, and probably not too hard to make it your cash/time ratio is inclined that way.

Cool Duo-mite page
http://ogict.com/instructions.aspx

LAZYBONES
01-01-2009, 09:19 PM
Too Soon Old, Too Late Smart!

davidh
01-09-2009, 07:12 PM
0.78 is a standard K&S size, they should have it at the hobby shop. I use a Duo-Mite bender for jobs like this, they're real handy, and probably not too hard to make it your cash/time ratio is inclined that way.

Cool Duo-mite page
http://ogict.com/instructions.aspx


are there any plans out there for this cool little bender ?

gellfex
01-10-2009, 01:45 AM
are there any plans out there for this cool little bender ?

No plans, but here's better pics. It's all 1/4 & 1/2 flat stock, except for the plates that hold the vise jaw on, which are 5/16 with most of the face milled off to make the shoulder that runs in the slot, which is 1/8 deep. That jaw is not particularly snug, it'll wobble 1/16 an any direction. No rocket science here. Good luck!

http://img.photobucket.com/albums/v358/gellfex/random/DSCF1967_editedsm-email.jpg
http://img.photobucket.com/albums/v358/gellfex/random/DSCF1971_editedsm-email.jpg
http://img.photobucket.com/albums/v358/gellfex/random/DSCF1965sm-email.jpg
http://img.photobucket.com/albums/v358/gellfex/random/DSCF1969_editedsm-email.jpg

Smokedaddy
01-11-2009, 12:05 AM
How much was that pup? Didn't notice any pricing on the website?

Regards,
-SD:

davidh
01-11-2009, 12:11 AM
i have not asked either. . . my guess you can';t get anything anymore for under $100 bucks. . . but i might be wrong. im gonna call them monday and find out.

im sure i could wind a spring on the lathe, i have done it a few times with good results. i did order a lb. of wire from mcmaster on monday so i will be able to make a few mistakes.

but its such a cute little tool..................

gellfex
01-11-2009, 01:15 AM
How much was that pup? Didn't notice any pricing on the website?

Regards,
-SD:

The original Duo-Mite is upwards of $250, but here's a knockoff for $80.

http://www.micromark.com/UNIVERSAL-BENDER,8229.html