shutters and magnets question

[mircea nicolae]

Hello,


I am building my own 6x17 camera.

It is a view camera, and I was thinking of using some rare earth / neodymium magnets to attach the bellows to the back of the lens board holder.

On the 4x5 camera I have, the bellows attachment system is identical to that of the lens board.
There is some kind of small metal plate that has a bit of travel, and it can block the bellows frame in place.

However, with the 6x17 camera I am building, it makes more sense to use something simpler.
I am also building the camera out of wood, and I do not have access to any metal tools.


My question is this.

Will the magnets damage the Copal shutter?
The shutter sits on the other side of the lens-board holder, at a very close distance.

I know that rare earth magnets are very strong.
I might be using 4 pairs of magnets with about 500 grams of pull force in total to hold the bellows.

The shutter is full of tiny metal parts, and I was thinking I would hate to have a nice bellows attachment systems at the cost of damaging my lenses.
I remember when I was a kid that my grandfather was always pointing out that we should not put magnets on our mechanical watches.

Unfortunately, this is as much information I have on the subject.

Can any of you contribute with some info, and tell me if these magnets are ok or not in this setup?


Any piece of advice is appreciated.

Thanks.

[Jim C.]

All magnets have a range before they grab, rare earth ones are no exception, their attraction
is greater and grab more violently. If the shutter is out of the range of the magnets
I don't see why you couldn't use them.

Why not just make a wood frame for the front of the bellows ? Lots of old view cameras used a
wood front frame for the bellows.

[mircea nicolae]

Thanks.

So basically it would be wiser to take the magnetic field out of the shutter's way.

[Ivan J. Eberle]

Just speculating here that you might end up over time magnetizing the shutter blades (if made of ferrous steel) or clockwork escapement pieces of the leaf shutter, and this would not bode well... so why the need to do this?

If you want simple and bombpruf, skip the bellows, make a fixed box and use one lens on a helicoid.

[mircea nicolae]

I guess I'll use a more traditional way of attaching the bellows.

A box camera is out of the question, because I would like to use all of my lenses, and have axis tilt for dof control.