From: Adrian Hodgson <adrian@aphtrading.co.uk>

I have found that the chargers transformers are only rated intermittently
and that they have a thermal cut out on them to cope with over heating that
happens when running toward there max load.

I would strongly go looking for ex equipment.

I have here (no user to you though Peter). 13.8Volt supplies from old
Motorola base stations which are good for 15 amps continuous. They weigh a
lot and have the heatsinks to match. I know that Motorola kit is bountiful
in the states so try some of the radio ham groups or hobby mags for surplus!

--
Cheers
Adrian
Homepage http//www.aphtrading.co.uk
Lathe and Champion Mill at http://www.aphtrading.co.uk/pages/apage1.htm
Better Foundry at http://www.aphtrading.co.uk/pages/apage2.htm
No longer trading.