Type S Mortar + Fireclay = good mix?

[eprante]

Re: Type S Mortar + Fireclay = good mix?

Fx,
I used plaster sand for my homebrew and it was very easy to work with. One cautionary note, I paid attention to people's mortar mix and the people who changed the formula seemed to have problems with cracking. I used the formula listed in the FB plans, cured slowly and had nothing more than some hairline cracks on the exterior of my dome, if I had put the mortar over the entire dome instead of just the soldier course I wouldn't even have known they were there. No need to reinvent the wheel unless you have some information from somebody you trust that gives you a reason to tweak the formula.
Eric

[fxpose]

Re: Type S Mortar + Fireclay = good mix?

Thanks Eric, I'll go ahead and mix using plaster sand after making sure the sand is completely dry. These plastic bagged sand contain a lot of moisture.

As far as the formula is concerned I've seen two diff sets of formulas thrown around here so I used the 3/2/1/1 formula. Perhaps I should stick with the FB recommended ratio of 3/1/1/1.

Thanks again,
George

[ThisOldGarageNJ]

Re: Type S Mortar + Fireclay = good mix?

Hey All,,
I used the heatstop50, My thoughts being a new builder were that by using it, I would take away some variables,, It was expensive, $ 57 per 50 lb. bag,, and I used 3 or 4, but i felt better with the security of "just add water" and it was very easy to work with..
Here is some more info which I hope doesnt confuse the issue

Mortar nomenclature has developed over many years to its current form. Designations for mortar are found in ASTM C 270, Standard Specification for Mortar for Unit Masonry. In the United States, the three common types of mortar specified for new construction today are N, S, and M. These arbitrary designations were assigned by taking every other letter from the term ?mason work.? Astute observers will notice that an ?O? and a ?K? also appear in that term. While these are recognized mortar types, they are typically used for non-load bearing walls and for tuckpointing or other repair work.
Mortars are differentiated primarily by their strength: M is the highest strength, S is next, and N is a moderate strength mortar. (O and K are lower strengths yet, which is important in repair work so as not to create a mortar that is stronger than the wall/units where it is being placed.)

If you think the strongest mortar is the best solution, think again. True, strong mortars do generally have increased durability and greater structural capacity. But, since much masonry is constructed as reinforced masonry today?there are steel bars added to the cavity then grouted solid to create a ?concrete? wall?the reinforcement and grout become the more dominant structural elements. The mortar itself is less important for its load carrying capacity than for its other aspects, such as facilitating placement of units.

Rule of Thumb: Use a Type N mortar for all masonry work unless there is a compelling reason to choose another mortar. C 270 provides recommendations for mortars choices in a concise tabular format as shown here. Note that alternative mortar types are also suggested, whether for availability considerations or for minimizing the number of different mortar types on the job site. Consult the appendix of C 270 for tuckpointing mortar guidance.


From ASTM C 270

P.S. To FX, When I was mixing my Vermicrete, I used a 1 gallon tomato can as SCAR recommended, Just dont pack down your ingredinets

[fxpose]

Re: Type S Mortar + Fireclay = good mix?

Hi Mark!
I already laid and set down the ceramic board. But I will still use Vermicrete over the blanket near the dome top and to insulate the vent/stove pipe.

As to the homebrew, I tested the batch I made and it seemed to set the bricks well. I will throw this over the BBQ this weekend to see how well it holds up. ....

George

[ThisOldGarageNJ]

Re: Type S Mortar + Fireclay = good mix?

Hey George,,
Glad to hear it... If and when I build another oven I amm sure I will go with the wayyyy less expensive home brew.. You know we want more pics.....
Cheers
Mark

[GianniFocaccia]

Re: Type S Mortar + Fireclay = good mix?

I think the last (and only) time I inquired about Heatstop 50 here in southern California it was closer to $80/bag which means now I'll get to try my hand at a second kind of homebrew.
John