[newarts]

The pentax hot shoe has 4 contacts plus ground.

Will harm be done if any or all of these contacts are short circuited to ground?

[SOldBear]

The pentax hot shoe has 4 contacts plus ground.

Will harm be done if any or all of these contacts are short circuited to ground?

No harm. But the flash is useless if "all of these contacts are short circuited to ground".

Why? Because the center contact is the sync signal. If it is shorted to ground, the flash will fire as soon as the capacitor is sufficiently charged (actually I've never done that, so that is only my guess).

Other than that, I think there's no harm done if any of the data pins is shorted to ground.

Let's just say that I've been using my AF540FGZ with a Spotmatic F without any problem.The hotshoe of the Spotmatic has only a center pin.

Edited to add:

So, I decided to do a little experiment to find out how the AF540FGZ behaves when all contacts, including the sync. signal, are grounded.

First, I attached a Pentax Hotshoe Adapter FG to the hotshoe of the Spotmatic. A Pentax Cord F5P connected the adapter FG and the AF540FGZ. I verified that the Spotmatic could trigger the AF540FGZ OK.

Now, I attached the AF540FGZ to the cold shoe of my Yashica Electro 35 G. The cold shoe is all metal, and that grounded all the pins of the AF540FGZ.

The result was not what I expected: the flash charged up as normal, and the TEST button triggered it OK. The problem was that now the Spotmatic did not trigger the flash at all. When I removed the flash off the Yashica, the Spotmatic could fire the flash.

There, you have the answer to your question: no harm done.

[newarts]

No harm. But the flash is useless if "all of these contacts are short circuited to ground".

Why? Because the center contact is the sync signal. If it is shorted to ground, the flash will fire as soon as the capacitor is sufficiently charged (actually I've never done that, so that is only my guess).

Other than that, I think there's no harm done if any of the data pins is shorted to ground............

SOldBear, thanks for the work. I couldn't imagine any damage by just short circuiting any of the contacts - if there were a danger the designers would likely protected them from accidental contact.

I ask because I want to make a metal bracket that slips into the hot shoe.

[elliott]

I ask because I want to make a metal bracket that slips into the hot shoe.

The contacts are recessed enough that you probably won't touch them anyway.