Three seasons ago, I replaced the RA330 secondary stub with RA253ma in my extreme burning Shop dragon.
Yesterday, I opened up the shop stove to make some springtime modifications.
The RA253ma stub is still as good as the day it was installed!
With a significant cost difference of $60 versus $90, I will no longer be stocking the RA330 tubing.
The RA330 sheet metal will still be available.
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RA253ma
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RA253ma
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RA253ma
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It is as good as the day I installed it.
This stove burns back-to-back full loads; I call it extreme burning.
The cast iron top from the same stove failed, while the RA253ma is only tarnished.
I routinely see these Ra stubs cherry red while adding more wood.
I'm confident that the RA253ma is a one-time purchase.
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For all your Montana Masonry Heater parts (also known as) Rocket Mass heater parts.
Visit me at
dragontechrmh.com Once you go brick you will never go back!
Hi Branden;
First-generation Batchboxes (the most common type) use a primary air supply at the door and a secondary air supply that brings fresh air to the rear of the firebox, directly in front of the riser port.
The secondary air mixes with the volatile wood gases, creating a flaming vortex inside the riser, often called a double ram's horn.
The RA stub is a replaceable part of the secondary air supply.
On my extreme burning shop stove, a carbon steel stub in this location will last apx six weeks before spalling apart.
The cast iron griddle was an experiment to see if it was a viable alternative for a batchbox roof material.
For my stove, which runs exceptionally long and hot, it failed miserably.
As the roof on a casual use batchbox (ie, two lightings a day), it is proven to last.
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Double barrel with brick bell shop stove
For all your Montana Masonry Heater parts (also known as) Rocket Mass heater parts.
Visit me at
dragontechrmh.com Once you go brick you will never go back!
thomas rubino wrote:As the roof on a casual use batchbox (ie, two lightings a day), it is proven to last.
Your red "smoking permitted..." sign reminds me of the "employees must wash hands before returning to work" signs in restaurants most places I've been. I've never seen signs like that at Wheaton Labs, does your county regulate dragon activity more stringently...?
For the Shop Dragon, smoking is only permitted out of the chimney during startup.
Although I do not smoke anymore, plenty of people still do.
I have no trouble with them lighting up.
As they used to say in the military, "Smoke 'em if you got 'em"
Much more important is the "No Tag Line, No Pick" sign
For all your Montana Masonry Heater parts (also known as) Rocket Mass heater parts.
Visit me at
dragontechrmh.com Once you go brick you will never go back!
She's brilliant. She can see what can be and is not limited to what is. And she knows this tiny ad: