RMH for Dummies! Please help guide me through my first build!

Caleb Mayfield wrote:My feeling is weather, and possibly wind, is the primary culprit.
If I load it up with larger stuff off the bat, or less fat wood it takes longer to get warm and I struggle to get it up to 500 F. It gets warm and gives off the heat we need, and looking at the chimney it's burning clean, just not as well as a good hot start.

Just a thought.

Good luck!

thomas rubino wrote:Staci; If it is weather, then you might try making your chimney taller outside.  I know the costs involved with that, to do it right.  If needed, you might just try and stick a piece of plain stove pipe on top and see if it has an effect. (remember it will not be insulated ) If it seems to work and you can't afford a new piece of insulated pipe, then insulate your own. Ugly but wrap it with insulation and slide a larger pipe over top.   Later if that solves your problem you can save up for a shiny new metalbestos pipe.

Graham Chiu wrote:Do you have weather data for your immediate region? In particular wind speeds? If not, can you measure it?

Staci Kopcha wrote:

Hi Caleb,
 Thank you for the suggestions!
Maddening enough, there was NO wind! Crazy.  They issued the burn ban due to the stagnant air.  I could understand high winds being a factor, but none..? Weird.
I appreciate the comment on using the smaller wood straight off.  I have noticed that too, when I am impatient to not want to babysit with smaller pieces, and instead add thick pieces... impatience does not pay off in best heating results.
Staci

Mark Tudor wrote:How big is the gap between riser and barrel? A normal burn with typical gap should be getting barrel top temps several hundred degrees hotter than 475 I think. Also don’t forget that normally it takes heat about one hour to travel through one inch of cob. So if you have say 5 inches on top of the bench those temps will take some time to increase. Wouldn’t a taller chimney cause even more trouble, if the issue is too strong of a draft pulling the exhaust through the mass too fast for full heat transfer?

Staci Kopcha wrote:Hi Graham,
 It is hilly terrain in my immediate area.  House is just nearing the top of a rise.
Got this from an on-line topo map:
Lng:-122.35285329999999
Lat:47.1702279
Elevation: 136m / 446feet

Thomas Tipton wrote:Hi Staci.

I've been following your build with much interest.  In regards to your RMH troubles, I just wanted to weigh in with my two cents.  First, I find it odd that you have trouble with the draft not being strong enough to keep the fire from creeping up the feed tube, but then we are entertaining the idea that draft is so strong it's preventing your mass from heating up.

From what I have seen I would surmise that you need more space between the top of the riser and the barrel lid.  While two inches of clearance should be enough, I just have a hunch this area is the point of restriction that is keeping your dragon from performing to it's fullest.  Maybe others can weigh in on this?

Good luck to you in resolving this issue.  I'm very much impressed with your accomplishment thus far.

Staci Kopcha wrote:RMH frustration.
At this point, I want to smash the second bench (after the "L"), as it is never very warm or retaining much heat. I suppose it would mess up the system, because there would not be the ideal duct length, BUT, honestly it is pissing me off. (Pardon my phraseology) The temp of the outside corner of the "L" read at 64F, 70-87'F is what the rest of it runs.
Perhaps I am under a misapprehension in that the second portion of the bench is supposed to be warm...??  What is a typical temp?  I will see if I can find it anywhere.
Maybe my expectations are out of wack??

Staci Kopcha wrote:RMH frustration.


 Today it has been running for 4.5 hours.  I used a mix of fir and madrona wood , with odd bit of cherry, alder, and maple - all very dry.
Chimney pipe inside the house at the very top is at 107F. First portion of bench is slightly warm to sit on, second portion cool.
Temps today were cold, and now 32F, snow is predicted.
Wind is nearly zero. Pressure is "29.41 in"

thomas rubino wrote:Good Morning Staci;
I suggest that for now, you put a candy thermometer in your chimney. Start monitoring your true gas temp rather than pipe temp.
I have been learning how different gas temperature's are from pipe surface temps.  And how rapidly that temp changes. It is a true indicator of rocket performance.

Staci Kopcha wrote:
1)  I added cob decorations to the manifold and bench, and as someone brought up at the time when I did it, it has since been cracking and sloughing off.
  How can I fix this?  If I break off and wet cob and try again, won't it just crack off again?

3)  Do I put plaster on the manifold and cob around the barrel in addition to the bench?

4) Do I plaster OVER the 3-d decorations  (see question #1)  or do I just make them out of plaster?

Kimi Iszikala wrote:...oops, never mind!

For some reason I was only able to see posts up to 8 months ago until I posted my question and now I see all the more recent post.  

And I'm not sure how to delete my post.

I guess I need remedial help with the forum before I get remedial help with RMH bulding!  

Staci Kopcha wrote:
Question:  some sites apply a "float coat" and then a final coat; float coat being different composition.  These projects are all in reference to plastering walls, however.
               For RMH bench, do I need a float coat?

                Note:  I AM going to wet the existing cob prior to adding plaster. ( A good saturation , waiting 3 hours and then a final wetting).

Gerry Parent wrote:

Staci Kopcha wrote:
I have to ask though, what is that clumpy red stuff in the pail? Clay?

Clay.  The place where I get my fire clay sells cheap blocks of clay- stuff they have leftover and not sure of firing temp.
Comes in various colors.  Not keen on the reddish, but okay for testing.

Dan Hatfield Ii wrote:Hi Staci,

I used air separated fire clay that came from a ceramics place. I believe the stuff you may be able to get hold of is called "lincoln 60 fireclay"

I used the potter's fireclay without any issue.  
I havn't sealed it yet so it's dusty (but very hard)
I need to find something to seal with that will not change the colour.
Lindseed will darken it.