Johnny Glades

straightening coil spring steel

Recommended Posts

Hi all, what is the proper method for straightening pieces of coil spring? I would like to use the pieces to forge letter openers, small caping knives, etc.
Thanks in advance........................
~~~Johnny~~~

Share this post


Link to post
Share on other sites

On smaller springs (3/8" diameter wireor less) I place a round rod (3/4" or whatever the spring will slide over) in the hardy hole of my anvil (my anvil is attached to a stump in the ground), heat up the spring, toss it over the rod, grab the bottom end of the spring with a vise grip and pull! On larger springs I weld a ring on to one end of the spring so that I can chain that end to my anvil stump. The spring is placed on a 2" diameter shaft which is chained to the forks of my tractor, which is then used to pull out the heated spring. All thats left to do is a little straightening of the spring on the anvil or under the power hammer.

Share this post


Link to post
Share on other sites

If I just need short pieces of the coil, I usually just cut the length that I need from the coil with a cutting torch and then heat and straighten the shorter pieces on the anvil.

Share this post


Link to post
Share on other sites

I have a couple coils from an old Range Rover, and was wondering the same thing.

I can't imagine heating up the entire coil (it was a suspension coil spring), and was thinking to cut it in sections first with a hack saw or similar.

You'd have to heat those puppies up good to pull them out with a tractor! I certainly don't have a forge that big I don't imagine, I'm not sure the coal forge I'm getting soon would do that large of a piece of steel.

What I was thinking of doing first was using the shock absorber rods from the old shocks, I hear those are really tough steel normally, and they're straight already which is a plus. As it is, I'm working on getting my 24" inch piece of 5/8" round rod forged into a 1/2" square rod...as my first project!:P Oh, I take that back, I made a beam hook already! :rolleyes:

Car/truck parts seem like a good source of good steel.

Share this post


Link to post
Share on other sites

I cut the length I want,,8 or 10" or so and heat it up,,then with bolt tongs stick one end in the hardy hole and pull. If you want to keep the piece nice and round you can finish straightening on the anvil with a wood mallet. If you are going to flatten just flatten and finish straightening as you go.

Share this post


Link to post
Share on other sites

You can straighten the whole thing out, but it is kinda slower than the other ways(I LOVE THE TRACTOR IDEA K.!),You take the spring and heat up a good section, then put it over the heel of the anvil so that the tip is just a little past the one edge on the side, and the rest is over the other side, then hammer on top of the arch that makes until there is no arch, and continue on up the bar until the whole thing is straight. One thing to keep in mind is to keep both sides of the "arch" in contact with the anvil edges. This will make sure you just don't RIP your arm out of the socket everytime you hit the top of the arch. Ever hear the phrase "beat the daylights out of something/someone"? Well if you have your anvil oriented so that the heel or horn is pointing at a window or source of light, and you put the arch over the anvil, you will see daylight under it, and when you pound on the top of the arch, you beat the daylights out of it! Also when you have a ring on a cone mandrel making it true round, you sight down the cone looking for open spaces between the ring and cone, and pound those out, hence you pound the daylights out of it/them/that guy(hehe)! Thank you, thank you, i'll be here all week!

Share this post


Link to post
Share on other sites

Heat up and roughly straighten twice the length you need on the anvil. Hot cut it from the parent stock. Work one end while holding on to the other without tongs. When you have both ends finished, cut it in half and make the handles or whatever from what used to be the middle.

Share this post


Link to post
Share on other sites

I ... was thinking to cut it in sections first with a hack saw or similar.


Take it from me, don't try to hack saw a 3/4 inch car or truck coil spring unless you want to use one blade per cut. Even a small coal forge with a decent blower will get a section of the spring hot enough to cut with a hardie or a chisel (using the chisel took 3 or 4 heats for me).

Share this post


Link to post
Share on other sites
Take it from me, don't try to hack saw a 3/4 inch car or truck coil spring unless you want to use one blade per cut. Even a small coal forge with a decent blower will get a section of the spring hot enough to cut with a hardie or a chisel (using the chisel took 3 or 4 heats for me).
ok, I'll take your word on that roy...but it's like the 'ol saying, "when you have a hammer, everything looks like a nail". I have a hacksaw! I do have a cutoff hardie, BTW.:)

Share this post


Link to post
Share on other sites

I usually squash them straight in a leg vice. It's a two-man job, but it works. Then all that is needed is to straighten the rod over the anvil.

Share this post


Link to post
Share on other sites

I've heard of several ways of doing this, but personaly I think trying to heat an entire coil spring is going to be 'interesting', if you can then putting it over a suitable round mooring point and pulling should certainly work (a tractor is fun but perhaps a tad overkill) If I was doing it for knives and such then I'd do it like Rich and just take what I needed, using a hot cut, and then straightening the section. Smiddy's way will work well too, if you get it hot enough.
Worth remembering that while you 'can' get some excellent steel from automobiles that are 'retired' it's not new steel and should be carefully checked for cracks etc, sometimes from what I've heard you can do all that and still have it fail on you, especially with knives.

Share this post


Link to post
Share on other sites

I used to use an abrasive cutoff blade in a skillsaw to cut off sections of coil springs lickety split. As long as you don't want more than one loop at a time it works great. Then straighten it out using the methods already posted.

Share this post


Link to post
Share on other sites

Back when I was tuning up my 150lb. Fairbanks hammer, I made several springs for it using all types of different truck coil springs. Uncoiling the springs and then recoiling them to the size I needed and then heat treating them to fit my hammer. This is how we did it in the blacksmith shop when I worked for the Burlington Northern Railroad as a blacksmith, except we used a forklift to pull the spring. The advantage to straightening the entire spring is that unwinds itself almost straight so there is very little forging to do. Straightening small springs isn't hard as it might sound. Here are a couple of pictures of straightening a spring. I use a tractor on the heavy ones but you could use any device you have for pulling........ken

1027.attach

1028.attach

1029.attach

1030.attach

Share this post


Link to post
Share on other sites

I did this very thing today! A friend and I just straightened 2 chunks of 3/4 inch car spring (possibly 4140) by heating in a large gas forge, and unrolling it using heavy tongs to hold it in position, a pair of bending forks on a 4x4 inch post, and a piece of 1 inch or larger square tubing. The tubing acted as the lever to straighten, the tongs braced and helped pull. We did final straightening on the anvil, using the step area to work more extreme kinks out, and the top plate for final tweaking.
We straightened two springs, and it seemed easier to heat 2 or 3 loops of the spring, straighten and let it cool, then straighten another section. When we tried heating the whole spring at once, it came uncoiled in a big mess, and was harder to handle.

Share this post


Link to post
Share on other sites
Back when I was tuning up my 150lb. Fairbanks hammer, I made several springs for it using all types of different truck coil springs. Uncoiling the springs and then recoiling them to the size I needed and then heat treating them to fit my hammer. This is how we did it in the blacksmith shop when I worked for the Burlington Northern Railroad as a blacksmith, except we used a forklift to pull the spring. The advantage to straightening the entire spring is that unwinds itself almost straight so there is very little forging to do. Straightening small springs isn't hard as it might sound. Here are a couple of pictures of straightening a spring. I use a tractor on the heavy ones but you could use any device you have for pulling........ken



WOW, you do some crazy work ken!

Share this post


Link to post
Share on other sites
I have a couple coils from an old Range Rover, and was wondering the same thing.


Alan,

If you have a pair of those then you must have a RR, either with a lift on it or you have replaced the springs?? Did you go to the MAR mudfest this year?

I have a 95 Disco and have a rear pair that I swapped out and have been saving to use.

Brian
Ottawa

Share this post


Link to post
Share on other sites

The way I use to obtain short pieces of coil spring (8 to 16 inches) to make tools etc, is to heat one side of the spring only. Then using a large long cold chisel? I think my first one came from the end of a crow bar! Having someone to help is useful till you get use to it. It needs some niffty work with a 4lb hammer and a retained, full width cutting plate is essential! The rings, whether 3/4 or 1. 1/2 coils can then be easily heated and straighten out.

Share this post


Link to post
Share on other sites
Alan,

If you have a pair of those then you must have a RR, either with a lift on it or you have replaced the springs?? Did you go to the MAR mudfest this year?
Yes, I do have an '88 Rangie, and yes, I did replace the coils and shocks with old man emu parts. I have the original coils (with driver side sag;-) and shocks. I thought I could either cut the coils up and pull the rods out of the shocks, I've heard those are pretty tough.
I have a 95 Disco and have a rear pair that I swapped out and have been saving to use.
Yeah, I have all 4 of mine, I swapped out all of them.

I have a set of D90 rims and tires on it. It has a mean look, but I never drive it anymore. I only drive it to get smog'd or pick up old woodworking machines.:rolleyes: I had a minor plastic explosion and the radiator shroud and fan both broke apart going up the grade to Lake Tahoe in CA. I was going to pick up an old Yates-American table saw, weighs 1600 lbs. (check out the carnage pic of the parts;-). I was able to McGyver that puppy back together and get home, and since have used it with no fan but a new water pump belt to pick up a couple other pieces of old iron.

I will never buy another english car/truck, but I'll probably keep the rangie. It'll make me happy to cut up the coils and shocks, although I have grown to know it's oddities, and the SOB does get me home typically...I have some great stories with it, that table saw was one I didn't think I would get home, but McGyver'd the AC belt to the water pump and it got me home (and the saw!;)).

Share this post


Link to post
Share on other sites

Take a piece of leaf spring and make a long chisel out of it so you only need to heat the section you want to cut and the chisel will go throgh the coil from the side to reach that section.

Thomas

Share this post


Link to post
Share on other sites

I think that one reason people like LR's so much is that they can McGyer them if things go awry - as they do a little too often.

The Disco is the most comfortable ride I have ever owned. I can drive for 7 or 8 hours and my back is as good as when I jumped in. This will probably be retired as a daily driver very soon but kept for the off road. Keeping a guzzling V8 on the road is kind of exspensive.

If LR reintroduced the Defender I would sell the Disco and buy one in a New York minute. But that seems very unlikely right now. LR claims that they cannot get the deisel engines to NA pollution control specs. I suggested that they buy a VW and reverse engineer it. No reply - gee.

Anyways - I do enjoy it.

Brian
Ottawa

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.