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TECHSHOP
03-07-2008, 03:27 AM
Now that most of the things I order at Cabin Fever have arrived, I need to hideout from SWMBO until the bills are paid off.

I have a replacement spring, flat coil "clock type" spring that I need to wind on its arbor and put into its cover. The only reference I have on this type of spring is an old "English" (UK) clock making/repair book, but I think I translated everything to the point of understanding and I had a new spring made.

It is "very stong indeed and quite beyond the capability of muscle the normal person is endowed with to insert by hand". However, this is a personal view, and may even be influenced by an inborn parsimony for I dislike buying specialist machines that take up space and can only be used for own purpose.
Any ideas?

Also, is silicone grease with molybdenum disulphide the best lubricant for this type of spring?

garyphansen
03-07-2008, 11:30 AM
Do you own a lathe? Gary P. Hansen

TECHSHOP
03-07-2008, 07:34 PM
Why yes, I do own a lathe.

I had thought that I could use a three jaw chuck (and tailstock center) to hold the arbor. Hold the "free" end, and wind the spring tight (I think I only need a "lever arm" approximately 20-24 inches long to turn this spring tight), slip on the cover, and then let the spring "relax" winding the chuck back.

Doing this would require more disassembly of the machine under repair, or making an arbor "proxy". Two things I would like to avoid (having already caught a black and blue finger and trashed nail with this spring).

Maybe, there is no other way?

mark61
03-07-2008, 09:38 PM
How bout using a drill press and hose clamp to hold once you have it wound?
It sure would help to see what you are working on and where it is going once it is ready.
mark61

TECHSHOP
03-07-2008, 10:03 PM
Maybe I am not being clear, but I think there is a bit of confusion on the spring type. The spring is like the one that returns the quill in a drill press, or holds up some car hoods, but larger. A "flat coil clock work spring" one end held to the arbor and the other end anchored to the cover. The spring has already been "made" and tempered, etc. I'm just stalled on the install, because a don't need another crack in my teapot (head). I can't wind it with a lever (strap wrench) on arbor shaft with the arbor in the machine (clearance issues), and this is a "five arm" type job. If I dissassemble (more) things, and do the winding on the lathe, I still have to move the spring back to the machine (under, less then full tension), reassemble/align everything, and set the finial tension, and (hopefully) not go back in there for another 25-30 years.

agrip
03-08-2008, 12:23 AM
Tech

If you turn a container cup of appropriate size, and wall thickness.
Saw and file an open end slot in the rimwall.

You can wind the spring on a slotted mandrel by cranking the spring in through the slot.

Said mandrel may be a turned/ adapted socket wrench extension. i.e. plenty of leverage available.

You then push the wound spring out of winding cup into the final container, by employing pusher holes that you have put into the cup end wall. Depending on the spring you use jack screw(s) to push the wound spring, yada yada.

The ends of such springs are sometimes tempered down some what from spring temper to allow some bending.
Sometimes there are well radiused notches ground into edges so the end hooks into a keyhole slot.

You know your spring end conditions, and other needs, so modify the description accordingly.

Sometimes the set up cup can be used to wind working tension, some times the setup mandrel is used. You already know that energy in small packages can be a gotcha, so you have to rigamarole the way you need it, but that rig is usually worth 3 of the 5 hands needed.

Moly-disulphide is ok as a lube.
polytetrafluroethylene dust does ok too.
Don't know about silicone grease beause of other effects, but a tacky lube (way lube?) should be a LLLooooong time drying out, and hold the lube dust within the wound layers.

Hth Ag

TECHSHOP
03-08-2008, 10:03 PM
Well, I set up the spring on the lathe, and had a good look before I started to wind. I thought to myself that it woud create a very large "character mark" on the lathe ways if it went wild.

So, I more or less reversed a shop made arbor in the headstock (the "gear" end), and used a winch (with ratchet/pawls) to crank the spring tight.

Which worked, but the new spring went "solid" at a greater diameter than the original and the cover wouldn't fit.

Back to the design stage...(bolt hole circles and springs)...you can't live with them...