Very interesting Sandy, may I show my ignorance and ask why the cross tubes need to me on an angle and does it really make a difference on a "toy" boiler?
Hi Kevin,
Not an ignorant question at all.
The tubes are angled so as to prevent air being trapped in the tubes which could cause them to become overheated... and yes it does make a difference as the angle also improves water circulation.
It is not, however, quite the same as the average toy boiler, since it can safely operate at very much higher pressure than most small toy boilers are capable of.
Hope that answers your questions.
Best regards.