Switch contacts for HV supply

[ThSpeakerDude88]

So I'm upgrading my HV supply on my bench with this

https://taweber.powweb.com/store/PTGPsch.jpg

I have a few wiring schemes figured out to get the following voltages after rectification: 250v, 280v,350v,390v,425v,450v.
I want to use a 6 position 2 pole rotary switch ( from radio shack) to give me the AC combinations I need before rectification, but am unsure if it is safe or not. The switch is rated at 125v 300ma. I think the most I would be pulling through it at 450v would be 150ma, and I wouln't operate the switch while on- only as a preset before the power is applied. Does anyone think I will have any problems with the high AC voltages jumping terminals or the high DC currents melting the contacts ( provided I am not operating the switch while the PSU is on?)

[Colt45]

If you only use it when it is off, it will probably be alright, but i'd like to get something with at least a 250v rating, if possible...

[ThSpeakerDude88]

know where to find one...? seems like the ones I find are all rated for switching "wall voltage."

[HollowState]

I would stay away from R-S switches for your purpose. They're nothing but cheap imported garbage. If you can't find a good ceramic rotary switch at a local surplus dealer or a hamfest fleamarket, then search eBay for "rotary switch" and you'll find some nice ones. Some are even available with buy-it-now. Try to get a non-shorting (break-before-make) style and you can switch with power on.

Victor

[ThSpeakerDude88]

I can see if Fryes has one, their about 17 miles from me. I don't like to use radio shack stuff, but never had a failure with any of their parts since their relativley decent.

I am going to be building a completly tweak-able preamp with rotary switches for capacitors, I am going to get cheap 12 position single pole ones from AES because they are only $1.50 each... and cheap is important since they dont have to handle much voltage and I need uhh... 12 of them.

For diodes, since I need a FWB, won't 1n4007's work? With a 47uf input cap, will there be much hash? If so can I use a low value film cap to suppress this, or should I bypass each diode with a cap?