Thread: re-setting springs

The driver and passenger side springs on landies don't have different "load ratings" (or spring rate if that is what you meant) - they have the same spring rate, just a different "free camber" side to side (your line in the chalk).

I have never heard of resetting springs using a pipe bender?

However I have done it using a sledgehammer and anvil. Bayside springs use a hydraulic press.

Make sure you set each leaf to a slightly greater free camber to the leaf above.

If you want them to remain at the new height, you need to heat them up with an oxy once reassembled as a pack. not too hot, just until they start to change coloue.

Mike

I thought you also had to re-tension the spring by heating and quenching to keep the new set in the leaf?

Diana

Originally Posted by Lotz-A-Landies

Mike

I thought you also had to re-tension the spring by heating and quenching to keep the new set in the leaf?

Diana

The professionals first heat up the spring , it becomes easier to bend ..... then they re-set/bend it as a whole pack , and then they finally temper the spring again with heat so it becomes springy again ...

I'm experimenting really .

I used to use JACOBS spring works in Melbourne , but they no longer exist I believe. They did large truck springs .

I would be very wary of applying heat without knowing the exact temp.

MIKE

Originally Posted by isuzurover

. Bayside springs use a hydraulic press.

Make sure you set each leaf to a slightly greater free camber to the leaf above.

.

OK thanks .. yes a pipe bender is a hydraulic press I guess

Originally Posted by series1buff

The professionals first heat up the spring , it becomes easier to bend ..... then they re-set/bend it as a whole pack , and then they finally temper the spring again with heat so it becomes springy again ...

No they don't. I have watched Bayside spring works reset mine. There is no way you can properly reset springs without dissassembling the packs.

They disassemble the packs, reset each leaf individually on a hydraulic press (each leaf slightly more camber than the last), then reassemble the packs, then heat up (no quench). This is basically a tempering process after the cold reset, and removes stress induced by the reset and any "memory" in the leaves.

The set they did for me they didn't temper, and they sagged within 12 months. They then redid them and tempered them the 2nd time (plus a front pair). That was done in 1998 and the springs are still fine today - despite LOTS of 4x4ing and carting 1.5 tonne loads of firewood.

Originally Posted by isuzurover

No they don't. I have watched Bayside spring works reset mine. There is no way you can properly reset springs without dissassembling the packs.

They disassemble the packs, reset each leaf individually on a hydraulic press (each leaf slightly more camber than the last), then reassemble the packs, then heat up (no quench). This is basically a tempering process after the cold reset, and removes stress induced by the reset and any "memory" in the leaves.

The set they did for me they didn't temper, and they sagged within 12 months. They then redid them and tempered them the 2nd time (plus a front pair). That was done in 1998 and the springs are still fine today - despite LOTS of 4x4ing and carting 1.5 tonne loads of firewood.

There is more than one way to skin a cat .JACOBS used to re-set in the whole pack . It wouldn't have been economically viable for them to do each leaf individually... would have taken hours to do just one spring , they used to do large truck springs aon a massive press they had . They used a hot process when bending , not cold .
This summary is useful

Spring steel is characterized more by its metalurgy than the tempering. There are many grades of steel and spring steel, all of which have varied carbon content and alloys to give it whatever properties it needs. The tempering provides the correct degree of hardness to let it spring properly, just as correct tempering and annealing makes tool steel approriately tough for its task. Too soft it will not hold its shape, too hard it can break too easily.

Bending cold will be difficult with any larger guage material. Cold bending can also lead to weakness as you are forcing the metal past its working point in order for it to hold the new shape. Bending always adds hardness to the metal which may not be desireable (think of bending a piece of metal repeatedly until it breaks).

Heating to bend will be easier to work, but you will need to retemper it. This will ultimately yield a better end result if the spring will be in a use that requires it to do a lot of work. Tempering though is not a simple task for a casual home do-it-yourselfer; it involves fairly exact heating and quenching to get it right. If the portion that you need to bend is not the actual working part of the spring, ie: the eye on a leaf spring, the tempering may not be as critical.

So it really comes down to what you are making the spring for, how durable it needs to be, and whether or not you can bend it cold.. ful:

Originally Posted by series1buff

[SIZE="3"]There is more than one way to skin a cat .JACOBS used to re-set in the whole pack . It wouldn't have been economically viable for them to do each leaf individually...

There may be more than one way to skin a cat, but not all of them are correct.

Sorry but that is dodgy, and would likely shorten the life of the springs and/or increase the stress in the main leaf. I still can't see how they can reset a spring pack as a whole with the clamps still on, and to remove and refit the clamps you need to disassemble the packs.

Then springs are manufactured they are hot rolled to the correct free camber - individually. Whether you are doing a hot or cold reset, it doesn't take much time to disassemble a pack and do the leaves individually.

When I designed my spring packs I had a copy of the SAE leaf spring design manual for automotive engineers. It discussed how and why each leaf needs a higher free camber than the leaf above it - which is not possible if you reset the whole pack in one go.

I just checked and it looks like JACOBS is still there in OAKLEIGH ...

If my home back yard method doesn't work in the long run ( likely ) ..... I'll take the spring to them to do it .

They have been in business since Jesus was a boy .