Hello. I posted this in a different thread but thought I would start a new one as the other was older.
I have been sourcing products and reached out to Marvel here locally. They sent me the specs for their Fire Mortar Mix and I was wondering if this can be used instead of the individual items. I am attaching the specs here if anyone has any advice I would really appreciate it.
While this appears to be a slightly lighter-duty mix than what we typically recommend, it looks to me like it would work for this purpose. 1250°F is at the lower end of the range but entirely within the capacity of the oven, which is unlikely to be heated past 1000°F or so. Also, it’s a dry mix (wet pre-mixed mortar sold in a bucket would be absolutely not acceptable as it is not weatherproof).
If the cost is less than $50 a bag, you’ll be saving some money over some other dry mixes.
Allow yourself plenty of curing time to ensure the mortar reaches a usable strength level.
Thanks @bikerbudmatt. This is only $30 bag through them so I thought it was a pretty good deal. I can ask them if they have something that is a higher temp.
So if I go with this, I am guessing I would not need the Portland Cement, Fire Clay, and Hydrated Lime. The Silica Sand I know is for the mix but I thought it was used elsewhere as well?
That does seem like a good deal.
You need Portland cement for the insulated base (filling the void with a mix of Portland cement and Perlite). You do not use Silica Sand for the leveling layer that goes over that insulated slab area. That requires Play Sand, which is an all-purpose sand that is clean and screened, and is coarser than the Silica Sand. (A fine sand like Silica would be a nightmare for leveling because it is so fine that it just compacts in place.)
Sounds like you’ll be good to go…and good luck!
Perfect! Thanks for the help! I do have the portland cement from the base instructions along with the Perlite so I am good for that. Makes sense about the Silica that does sound like it would be a nightmare.
Is there a reason you don’t want to make the custom mix in the oven specs? Just asking because when I use my infrared thermometer the oven walls, especially at the back is at least 1050 degrees (the thermometer maxes out at 1050 and shows ‘high’ when the maximum is exceeded) after baking pizzas for a few hours. Like @bikerbudmatt mentioned, the premix may be on the low end, so not sure I would use it.
No particular reason really other than I figured if it’s premixed the ratios would be perfect, or at least one would hope. Other than I haven’t found the fire clay easily here in AZ. But I am sure I can. I haven’t found the specs on what the mixture they recommend comes in at so I wasn’t sure what temps the mixture we make can withstand.
I don’t want to risk any issues so if I can figure out the suggested method I have no problem sticking with that.
@CMG I noticed that you had another post that you purchased your fire clay from Zoro or something like that. Did that work out for you OK?
@Gulfstream5 yes, zoro.com had the best price by far for the fire clay and a flat $5 shipping fee. Zoro.com is the retail site for industrial suppler Grainger. I think I also got my ceramic fiber blanket from zoro.com.
Hope this helps!
Great! Thanks for the quick response. I think I will just do that and go the tried and true method. Better to not risk it. I did order the Grande kit so I have the blanket with the kit but Zoro did seem to have a good price on the clay. Thanks again for the info! Very much appreciated.
Don here in Payson. I used Paragon fire mortar from Marvel in 2020 for my oven and have had no issues at all - have had the oven above 1000° many times.
Marvel during Vid time was a life…no oven-saver!!
BTW - if you need extra ceramic blanket, i have extra i could GIVE you. I put 3 blanket layers on my oven, hence the extra. Also 10-4 on the clean PlaySand.
And as always, StudBud is the Barista of the Barile!!
Hi Don. That’s good to know! I am in Cave Creek. I was debating on if I should put a second layer on or not. I of course have the initial layer to put on. We just finished the insulated base so once that cures we are off to the build of the dome.
Yeah, my oven is in Payson, but i also live in Scottsdale. I was going to offer a big bag of perlite, but it sounds like you are pass that point. Have left over bricks as well (Pacific from Marvel). I put my oven on a elevated concrete driveway slab, so I didnt build the elevated base (calculated the resultant oven was only putting ~2psi on the existing driveway slab). You have a great product with very thorough instructions and Professor Matt to help - you are in good hands! Let me know if i can help. Bon Camino!
Thanks @AZDon! I am past that point….just moved past it today actually. Mixed it up and we put the mixture in and are waiting for it to cure. I would be interested in the blanket and wiling to buy it from you. Maybe if you can send me a private message I can get your info and talk about it.
