11 replies to this topic

[Stevee]

Straight Cut Gears and drop gears

why are they so expensive?

there alot easier to make than Hecial gears used in standard gear boxes

anyone shed some light on this?

[Mini Cheddars]

I don't know much about them but I'm alwatmys reading threads on the subject.

What I'm guessing is that because their use is more for racing, they're made of tougher metals/heat-resistant metals.

[Timtom]

They are made in small number? - Wing mirror mirrors are cheap because they are made in mass number because people buy them alot but not very many people buy the drop gears/gearboxes so they cost alot!

[Stevee]

are they though

all gears are made from High Carbon Steel then hardend

unless there using lightwight materials

[nicksuth]

I think there's probably two reasons?

- Straight Cut Gears are produced in less quantities so the proportion of the set up costs are higher

- They are considered a "Premium" product so suppliers can charge more (main reason ??)

There are a whole range of materials used in the manufacture of gears with chrome, nickel and molybdenum being the high cost elements and many ways of hardening; through hardening, case hardening (carburising or nitriding) and induction hardening.

I would say that the drop gears are most probably nitrided or carburised and possibly finished by grinding (not always needed on nitrided gears as they can be precision hobbed before heat treatment and still retain adequate surface finish.

Edited by nicksuth, 13 February 2011 - 04:36 PM.

[Paul Wiginton]

A few hundred quid for the gears is not expensive really, but add to that the gaskets, shafts and bearings then it does add up, then a couple of hours labour to build it all

Edited by Paul Wiginton, 13 February 2011 - 05:50 PM.

[Turbo Nick]

minis are cheap to modify when you compare them to normal cars!

[mini-geek]

minis are cheap to modify when you compare them to normal cars!

very true!... but I find it just expensive in the long run because you can do soo much to a mini..

anyway back to the OPs post

you are comparing the cost of new old stock items against new items I imagine of you had gon to rover back in they day it would of been a hell of a lot more expensive ... and supply demand there are loads of helical drops around we are hardly run out, but SC drops are not easy to come by so they are more expensive

[mini93]

development comes at a price, so thats added onto the price of each unit, the material etc...not going to be just plain ol carbon steel either.
And as others have said, the unit run for each, they arent just churning out gear after gear, they have to do them in batch quantity rather than a run so theres extra set up time etc which amounts to further costs.

[MRA]

In th emain part the SCCR items are made using more expensive higher strength steels, they are machined to a blank, then gear cut then heat treatment is applied then they are finish ground, if you made 1000 sets then the steel quantity would be higher making the piece part material costs lower....

The set up time is normally fairly low as these are repeat products, the heat treatment isn't too bad, however that really depends on type used, if for example you are having the teeth flame hardened that can be a an expensive method to "tool" up.

Don't forget that during production the standard gears would have been made in quantities of 20 to 30 sets per hour so tooling and machines would have simply been set up and left to get on and create swarf.

Aftermarket would incur a tooling setup cost because the batch would be for say 100 sets every couple of monthes...

Edited by mra-minis.co.uk, 14 February 2011 - 09:29 AM.

[Stevee]

Thaks for all the replys , it all seems alot clearer now. thank you

and yeah mini are alot cheaper mates civic just kit the 4k mark on mods now.

and thanks martin i get what you mean by all that

thanks everyone.

[MRA]

That's ok Steve