Quickie chassis

[Grainger49]

I used hole punches to step up from the 9 pin to a 5 pin socket for 76 drivers on my Paramours.  It didn't distort the metal.

[4krow]

  G,  Since I may buy one, I have one last question. How do you center a punch? If the hole is even a little off the mark, it shows.

[2wo]

Cut a few squares of card stock, like from a 6 pack holder or business card.
 What comes first to hand says a lot about us 
Cut a hole as close to the size of the center screw of the punch as you can. Now use this to center to the hole you want to enlarge and stick it down, rubber cement works great for this kind of work.

Put a sheet of card on the other side of the plate, when you punch. This gives you a chance to get everything square and the punch started in the card, before you start in on the metal and will protect the plate from tool marks...John         

[4krow]

  John,

 That rings of advice from experience. Thanks. Will do.

[aragorn723]

  Rob,

    I don't know what stepped bits you use, but mine have a chamfer built in to de-burr the holes. I use Irwin bits when I can afford them.
 

    One question that I have about the hole punches. Do they distort the metal when used?

What type of stepped bits do you use, titanium?  I have a drill press (but never used it lol) so that shouldn't be an issue, but if I look at Lowes website, there are titanium, and I think cobalt too?

[Paul Joppa]

Hold the phone!  Has this been discussed before?  I must've missed it.  2 D batteries in series will last longer?  Does this call for any other changes?...

I don't recommend it, especially at the stock 36v B+. The upper half of the filament is essentially cut off, giving increased output impedance and reduced linearity. To double the life, put two D cells in parallel as PB suggests.

[edited to say PARALLEL - oops!]

There used to be larger industrial NiCd cells (larger than D cells) - I don't know if they still exist, or (most important) if they are available with the recent long-shelf-life feature. But the 1.2 volts of a NiCd is maintained through the discharge and should be close to ideal for a Quickie.

[corndog71]

Thanks, PJ.  I think I'll just stick to the stock circuit.

[Paul Birkeland]

I don't recommend it, especially at the stock 36v B+. The upper half of the filament is essentially cut off, giving increased output impedance and reduced linearity. To double the life, put two D cells in series as PB suggests.

There used to be larger industrial NiCd cells (larger than D cells) - I don't know if they still exist, or (most important) if they are available with the recent long-shelf-life feature. But the 1.2 volts of a NiCd is maintained through the discharge and should be close to ideal for a Quickie.

The possibility would come along with biasing the center of the filament.