DIY Spring on a lathe?

[Privateer]

Any advice on how to do this and what wire to use?

I figure I can turn a brass rod to the internal diameter and drill a hole as the holder to start winding.
But what should I watch for?

[nervoustrigger]

Jeff, I've only made a few small springs but the way I approached it was the same way you are describing...by making a simple mandrel with a hold-down screw to pinch the music wire.  I used my floor-standing drill press and rotated the quill by hand so I could easily control the winding process.

This Old Tony has an excellent video on it:



For those who already know how to make a spring, it's worth a watch just for the production value and humor.

Regarding the type of wire, I use music wire.

[sb327]

I use music wire as well.

The mandrel will need to be smaller than the intended id. I usually use drill bit shanks to test to see what size I need.

I use a cutoff blade set so cutting edge is above mandrel so it can ride against it and guide the wire. I set my change gearbox for the appropriate pitch. I bend the end of wire to catch between the jaws of the chuck (this takes a little practice to know what works). I usually take a couple turns on the mandrel then engage the leadscrew.

Once you have your spring wound, be sure to temper it at 450deg (I use a toaster oven). Some say 1hr but 15-30minutes works. This will keep your spring from taking too much set once compressed.

Good luck.

Dave

[JPSAXNC]

I use music wire to wind springs, and long drill shanks for mandrels. The key to getting the spring OD. that you want is the tension you put on the wire while it's being fed. If the tension is to light the OD. will be to big, it's best to have as much tension on the wire as possible. I engage the threading feed for spacing and turn the chuck by hand, because the spacing doesn't always start exactly as you want. And if it's a long spring, mandrel flex will cause the spacing to change, turning the chuck by hand lets you make adjustments as you go. Also when the spring is wound, while the wire is still under tension, grab the wire near the last coil with a pair of long nose pliers and hold on to it tight so that the spring can't unwind when you cut the wire with your other hand. Still holding the wire let the spring unwind slowly. If you just cut the wire and let the spring unwind with a snap, the OD. will be to big.

[JPSAXNC]

PS. Another thing you can do is when the spring is wound, while the wire is still under tension. Disengage the thread feed, and carefully work the coils back into a coil bound condition. That will cause the tension on the wire to relax a bit, while the spring is coil bound then increase the tension on the wire as much as you can to stretch the wire a bit. Then release as above, the spring won't take a set.

[KWK]

Jeff, I've only made a few small springs but the way I approached it was the same way you are describing...by making a simple mandrel with a hold-down screw to pinch the music wire.  I used my floor-standing drill press and rotated the quill by hand so I could easily control the winding process.

This Old Tony has an excellent video on it:



For those who already know how to make a spring, it's worth a watch just for the production value and humor.

Regarding the type of wire, I use music wire.

This Old Jabroni.......Full a baloney. Too squirrelly.

Stress relieve in the oven an hour or two at 300-350. From "tool engineers handbook". Seriously.
Make two and relieve one. Then test them

[Privateer]

All good info Guys.
@ Jason
I did see that video linked and picked up a couple programs from the link in it.
Had to install DosBox to run them but it's working.

I have some Stainless Steel rod that I could use to make mandrels if I need to.
Also have brass rods.

I'll have to pickup some Music wire and play around some now.

Main reason for making my own springs is for My Evanix Guns.
Now. Someone is sure to say "Buy some springs from Blah blah."
Well, I'm retired and have the time and I want to learn something! Not buy a bunch of springs that will probably never be used.

[tkerrigan]

I bought a set of transfer punches for mandrels, they are by the 64th of an inch, 1/16 to 1".  I use 1/16 to 1/8 smaller that the ID of the spring I'm making. I also drilled a .090 hole in the end of the chuck for the start of the spring.  I use a guide block .5 x .5 x 2.5" with a hole drilled through it and a screw threaded from the side to add adjustable drag.  Regards, Tom

[Privateer]

I have a bunch of rods that I grabbed from demolition jobs over the years so don't need to buy stuff for mandrels.
I plan to make a tensioner from one of the Tool holders. I have 2 quick change Tool post setups.
I'll use the stuff that came with the lathe to do the tensioner. I don't want to mess with the new setup I bought.

I got the lathe several years back from an old grumpy Guy and never was home much to use it!
Now I have the time to learn more of what I want to learn. I did find a place with calculators that gives me a lot to play with.
https://www.thespringstore.com/spring-calculator.html

I'm interested in learning how to make springs to a rate I want and not just willy nilly.

[sb327]

This is only my experience so before anyone cries foul on my OPINION here, keep in mind I have made lots of springs over the years.

I do not use a tensioner to wind springs. The tension is created by how close I keep my tool holder to the mandrel and the bend radius of the wire. As you wind by hand, do not let the chuck backspin. I made a tensioner early on but discovered over time it wasn’t really needed.

Using a tensioner is not wrong and it does provide some control in the process but changing tension during the operation doesn’t change the finished dimension of the spring. Tight around the mandrel is easily accomplished without and pulling tighter doesn’t bend the wire into a tighter circle.

Again, only my opinion based on many years of winding my own springs.

Dave

[Privateer]

I like to read everyones opinion. Don't mean I prefer one over the other seeing as I'm just starting the journey.
May even come across a way I prefer to do things.

[Privateer]

So using the calculators? The spring I have has a rateing of 10.542 lbs/in +/- 10%
I'll play with settings for wire size to get a lighter and a heavier spring.
Wire size on this spring is .040

This is the Valve pin spring in my RainStorm 1
I plan to make a slightly higher and a slightly lower spring for testing.
I'll get to the hammer Spring after that.

I do want to credit Motorhead for inspiring me to mess with this.
His thread about the RS 1 sent me down this path in a way.

[rgb1]

Machinery's Handbook has a very good section on making springs.

[rsterne]

Here is a handy mandrel calculator....

https://www.daycounter.com/Calculators/Springs/

If you have a lathe and want to wind by hand, make a handle for the headstock....



It tightens like the seat post on a bicycle, a taper-lock....



but PLEASE make sure you UNPLUG the lathe before inserting the handle!....

Bob

[Privateer]

I like that hand crank Bob! I'll have to make something like that for sure!

The program I have is also based on Kozo Hiraoka's work.
It's 16 bit so have to run it in DosBox but it works.

[KWK]

Here is a handy mandrel calculator....

https://www.daycounter.com/Calculators/Springs/

If you have a lathe and want to wind by hand, make a handle for the headstock....



It tightens like the seat post on a bicycle, a taper-lock....



but PLEASE make sure you UNPLUG the lathe before inserting the handle!....

Bob

You must always cycle my shapers once by hand to verify the setup won't crash. These two require you to use the vise wrench on the jack shaft. I made a clip on knurled aluminum knob (shown) for the Boxford that can stay in place during operation but the Logan is harder to turn so I still have to use the wrench. Gets real exciting if you forget and turn the machine on with the wrench on there.

[Privateer]

I'll add a hanger of some sort to clip the power cord plug near the crank.
Then I should be smart enough to remove the crank before plugging the lathe in.

[Rocker1]

 yip Ill beat my self to death with that. David

[WobblyHand]

For hand turning, I have used the split bicycle shank idea mounted onto a 6" hand wheel.  It's big enough to get some torque on it, but not so large that if it accidentally starts spinning it shouldn't beat me to death. 

Used a hand wheel similar to https://www.grizzly.com/products/grizzly-cast-iron-handwheel-6/h3189  FYI, nice handles are more expensive than you'd think.  Don't remember where I got the handle from.

Edit: Later I found out that using a nut was a bad idea.  Replaced the nut and stud with a socket head cap screw.  That way I could loosen the screw a couple of turns and tap the screw to free the slip joint.  Much easier!

[WhatUPSbox?]

Bruce, That's a proper Man-Cave.