[Amps] Sources of CPVC for GS35b Chimney

[Tony King - W4ZT]

Kevin,

I have experienced failure of PVC used as a chimney. This failure was 
NOT due to temperature. See <http://gs35b.com/pvc/>. Though this may be 
a rare occurence  it is certainly worth considering.  Although CPVC is 
rated for use with hot water, it typically has more additives, 
particularly those pigments which change the color of the pipe. It is 
impurities in the plastic that may be the cause of the failure in RF fields.

I have NOT seen any reason to not use PVC because of temperature.  The 
cause of the impurity problem appears to be in the manufacturing process.

73, Tony W4ZT

Kevin LaHaie wrote:
> Hello group
> 
> Among the many amp projects I have in the works, one is based on the GS-35b.
> 
> Per Jim, K7RDX, 'Hot Water Rated' PCV in the 4" size is the perfect
> size and a durable material for a chimney.  This is known as CPVC to
> the pipe world, and apparently is good to several hundred degrees F.
> 
> So, run to the local pipe or plumbing shop and get some, right?  WRONG!
> All the places I tried only stock it sizes up to 2".
> 
> You can imagine their delight in my asking for 1 FOOT of the 4" size
> (still way more than I need!).  I was told that it comes in 10 foot
> lengths, and to special order it I may need to buy a pallet full.  This
> may be different depending on the relationship one has with the shop,
> but a 'walk in off the street ham' won't get any special favors!
> 
> So, here perhaps is an opportunity for someone to buy a stock of 10
> footers, cut it into 1 foot lengths and provide us GS35b amp builders
> what we need?  Maybe offer to silkscreen the tube number on it? Your
> callsign? Your Amp's Name? (Ampzilla, for example)
> 
> Just kidding. hihi
> 
> Does anyone know of a source of this in small quantities?
> 
> Thanks!
> 
> Kevin K7ZS
> 
> 
> 
> 
>