Making a spring steel spring?

[john_morris_uk]

An update;

I’ve been in touch with Spring Steel Strip to Hobbyists and Model Engineers and unfortunately they say they cannot help. Here’s their reply:

Hi John,
Further to our telecon and your sample.
Unfortunately , we are unable to manufacture your final spring part,
We have tested – your sample.

Hardness = hardness value.
Hv – 430
Tensile hrc rockwell 44.
Width 13 mm wide
Gauge = 0.40 mm .

We can offer 1 sheet of stainless steel spring steel : Grade 301 European 1.4310 tr 380 to 450 range. Spring steel.

1 sheet 1000 mm long x 300 mm wide x 0.40 mm .

Price = £205.00 pounds lump sum plus vat delivered to your house/factory.

Please let me know if this stainless steel is of interest? Or if we can be of further service. We will post your sample back to your Worcestershire Address.

Obviously I’m not paying £200+ for a sheet of s/s so I’m back to square one.

I’ll try other sources. Otherwise if anyone has a few cm’s of 0.4mm spring steel 13mm wide I’ll try tempering forming etc myself. It’s not critical as it’s just got to hold a pawl in place on a ratchet wheel.

 

[penfold]

half inch spring steel

 

[ean_p]

Old mortise locks have useful bits of spring steel inside.....

 

[Poignard]

My offer in post #5 still stands BUT I have just boarded the ferry to Caen and won't be back for several weeks.

I don't see any problem posting a bit of clock spring to the Caribbean or maybe you have crew flying out.

 

[Neeves]

But isn't he sailing in New Zealand atm? Sold up his workshop etc.

Maybe - but would not stop him giving you advise - the internet is marvellous.

Jonathan

 

[andsarkit]

As an incorrigible hoarder of useful bits I have this piece of metal which was some sort of spring catch.

It is 0.4mm thick and stainless but magnetic so probably 304.
If it is any use I can put it in the post.

 

[Zing]

Rob a part from something else. Cut down a bulldog clip or similar. This sort of thing spings to mind:

Simplicity 50 x Greenhouse Glazing Clips

 

[john_morris_uk]

My offer in post #5 still stands BUT I have just boarded the ferry to Caen and won't be back for several weeks.

I don't see any problem posting a bit of clock spring to the Caribbean or maybe you have crew flying out.

I’ll take you up on your kind offer. We’re in the UK until the end of October. (We’re on our way to catch a flight to France ourselves atm - my sister lives near La Rochelle) I’ll pm you.

 

[john_morris_uk]

As an incorrigible hoarder of useful bits I have this piece of metal which was some sort of spring catch.
View attachment 161457
It is 0.4mm thick and stainless but magnetic so probably 304.
If it is any use I can put it in the post.

That’s kind but I’ll try the bit of clock spring from Poignard first if I may.

 

[vyv_cox]

I assume that a stainless steel spring would be heavily cold rolled (apologies if this has been said earlier in the thread). I am guessing you do not have a rolling mill but beating the daylights out of a small sheet with a hammer might achieve something like

 

[vyv_cox]

As an incorrigible hoarder of useful bits I have this piece of metal which was some sort of spring catch.
View attachment 161457
It is 0.4mm thick and stainless but magnetic so probably 304.
If it is any use I can put it in the post.

More likely to be 410 or 413. 304 is mostly non magnetic, although turnings and low quality versions can be slightly magnetic.

 

[tico]

How about a piece cut (by dremel) from a paint scraper/filling knife blade. Annealed (cherry red & allowed to cool) then formed, then rehardened (cherry red then quenched) and tempered (heated gently until blue then quenched)

 

[john_morris_uk]

I m

How about a piece cut (by dremel) from a paint scraper/filling knife blade. Annealed (cherry red & allowed to cool) then formed, then rehardened (cherry red then quenched) and tempered (heated gently until blue then quenched)

I might be doing a bit of that with the clock spring. It’s certainly got to end up with a hole in it to allow me to fix it in place. The original has an end turned over at 90 degrees to stop it twisting.

First trial will be using a Dremel to grind a fixing hole. Then see if I can bend the end over enough to act as an anti-twist bit. If this doesn’t work I might try annealing and doing the drilling etc before hardening and annealing back to some sort of springiness. The whole springiness thing isn’t too critical. It’s just got to ensure the pawl ratchets on the teeth of the mechanism.

 

[Hydrozoan]

half inch spring steel

IIRC I may have used that supplier when I wanted a new spring for a woodworker's vice and it came with hardening, annealing and tempering instructions. A much longer piece than JM needs - but not expensive and plenty for a number of trials (probably necesssary!) and for making spares.

 

[vyv_cox]

I m

I might be doing a bit of that with the clock spring. It’s certainly got to end up with a hole in it to allow me to fix it in place. The original has an end turned over at 90 degrees to stop it twisting.

First trial will be using a Dremel to grind a fixing hole. Then see if I can bend the end over enough to act as an anti-twist bit. If this doesn’t work I might try annealing and doing the drilling etc before hardening and annealing back to some sort of springiness. The whole springiness thing isn’t too critical. It’s just got to ensure the pawl ratchets on the teeth of the mechanism.

In similar applications only the looped end is annealed. Hold the springy part in a vice to act as a heat sink. Heat the end to red heat and let it cool in air (normalise). It should then be soft enough to roll but not so soft to be very weak.

 

[john_morris_uk]

So here’s an update.

Many thanks to Poignard for supplying me with a click spring. I also found a bit of spring steel strip as another option.

My metal snips managed to cut the spring steel so I squared up the end and tried bending over the 90 degree bit on the end that stops the spring from swivelling round its single mounting screw. Predictably, the spring steel was too brittle and the ends snapped off. (See pic below).

So I held the main part of the workpiece in mole grips and heated the end I needed to work in the blowtorch to cherry red. Allowed to cool naturally and bent the end over as best I could in the little vice I have onboard.

I then marked and drilled the 6mm hole and formed the shape of the spring using fingers and the vice. I’m about to fit it and see how it goes.

Should I have a go at hardening and tempering? I’ve got a laser thermometer thing so I could check the temperature.

I’m inclined not to bother.

 

[vyv_cox]

Stress at the attached end is considerably less so I would go with what you have and see what happens.

 

[Daverw]

I would not bother hardening but if you did just heat carefully to light cherry and quench it oil, will also blue the steel

 

[john_morris_uk]

Stress at the attached end is considerably less so I would go with what you have and see what happens.

Fair enough. I’ve got enough spring steel strip onboard to make at least twenty more of the little bu**ers if this one fails.

 

[john_morris_uk]

I would not bother hardening but if you did just heat carefully to light cherry and quench it oil, will also blue the steel

Good tip. I’ll try applying a liberal amount of grease as a first attempt to preserve it.