The Morgan's WFO build

[ThisOldGarageNJ]

Re: The Morgan's WFO build

Hi Morgans,
Some people cure just the dome,, before isulating, some cure after... I cured after insulating and vermicrete,,, I think I waited three weeks then started the 7 day fire process,, I was very lucky and to date not a single crack.. (It wasnt easy waiting) I like the idea many people had, they used the burner from a turkey fryer and cured with propane, very controllable, even a small heater could be left in there,, this is one time where slow and easy definitely wins the race,, as far as polishing,

Neil2 says I used a 5 inch grinder with a set of 4 inch diamond grind pads (50 grit to 3000 grit, $120). Grind wet. It is messy but the pads will last forever. I've used the same set for 7 counter tops so far. When grinding dry, it is the heat that destroys the matrix holding the diamond material.

That sounds good, I am looking again for a polishing set, will keep you posted
Mark

[vintagemx0]

Re: The Morgan's WFO build

Wow, I suppose those $7 dry ones are meant for something other than putting a fine polish on a large table top. It's good to know, thanks. It sounds like a lot of people have been down this path, so it must be cost-effective in the end. I may wait until next year on my bench, but when the rainy season starts here, it may be a good time to make a mess...

We started building our ficade this weekend, but I ran out of blocks at about the same time I ran out of motivation. I decided to take this Sunday afternoon "off". We did manage to keep the curing fires going. We're up to a small multi-branch fire somewhere around 400 degrees. I pulled some of the insulation back to feel the dome. It was quite warm, somewhere around 200 degrees, and you could feel the moist warm air hit your hands as the insulation was pulled back. We also saw a hairline crack running latitudinal across the refractory mortar coat. No noticable fractures inside just yet.

Is it wise to cure with all the insulation in place? Is there anything we should consider when having the insulation in place during the curing process?

We will continue to build up the ficade walls in the evenings this week and keep the curing fires burning. Despite how much we get done during the week, pizza on Friday night is looking like a definate possibility!

The Morgans

[ThisOldGarageNJ]

Re: The Morgan's WFO build

hey neil,,, the Harbor Freight pads are DRY only, I just figured for the 7 bucks i'd give it a shot,, Nothing ventured,,,, I had previously bought a 300.00 set on ebay from a foreign importer,, Never arrived,, I finally got my money back from paypal,, so im looking
for a good wet system
Mark

[Neil2]

Re: The Morgan's WFO build

"But at a cost of 7.$ per area of about 10 x 12 inches, its gonna get too costly"

I used a 5 inch grinder with a set of 4 inch diamond grind pads (50 grit to 3000 grit, $120). Grind wet. It is messy but the pads will last forever. I've used the same set for 7 counter tops so far. When grinding dry, it is the heat that destroys the matrix holding the diamond material.

[olddude]

Re: The Morgan's WFO build

doing the same thing just bought wet polisher on line for 170.00
when it comes in i can let you know how it works tried a diamond grinding
on a peanut grinder to cut the rough stuff off work good so far
have a test peace that about 2x3 it it works will be a shelf

[ThisOldGarageNJ]

Re: The Morgan's WFO build

HI morgans, had my first attempt at the concrete polishing,, with the Harbor Freight Dry grinding blocks, looked ok, But at a cost of 7.$ per area of about 10 x 12 inches, its gonna get too costly, so im on ebay this morning looking for a more practical "professional" solution Will keep you posted,,, Keep going with the nice work

Mark

[vintagemx0]

Re: The Morgan's WFO build

We tried to make a little push today. During the evenings last week, we applied a coat of RefMix mortar over the dome.



And today, we received our ceramic blanket from Forno Bravo and applied it. 3 inches of insulation should be enough - one would think!



Since Thursday, we have been burning some newspaper and today we started burning little twigs of wood - low and slow...



We kept feeding this little fire for about three hours. We never let the fire get much bigger than what you see here, but kept it going. The outside of the dome at the top was just slightly warm to the touch after about 2-1/2 hours. We'll keep going low and slow and gradually increase the burn-rate over the next week or so.

So, tomorrow we hope to get the ficade walls up and fill in the voids with perlite/portland. We are under the gun now to get it weather-proofed before the rains come.

The Morgan's

[vintagemx0]

Re: The Morgan's WFO build

Sounds like the position we're in Darius. I live in Portland Oregon (which is notorious for it's rain), and we feel a little under the gun to get ours buttoned-up before the rain starts. It usually starts dumping pretty good around halloween, but it could come sooner or later... I look forward to tracking your progress and will "feel your pain" when we're racing the rain.

Ken Morgan

[KINGRIUS]

Re: The Morgan's WFO build

Cool. You're right, this forum concentrates years of techniques, tips and tricks, and other's mistakes that we can learn from and get our oven build the way we want the first try!
I have the rest of this week devoted to setting the oven floor and starting the dome. Just in time for us to be in for a weeks worth of rain!
But I built a canopy over my project today- The Show Must Go On!
Darius

[vintagemx0]

Re: The Morgan's WFO build

I think you're right Darius...beginners luck! Lucky to have been able to pour over all the good work on this forum too. We just used a bar clamp mounted on a swivel to set the bricks on an arc. We used a couple of discs propped-up to hold the upper last few courses in place. We got all these ideas from the forum here.

[KINGRIUS]

Re: The Morgan's WFO build

It's been fun so far, but we are having to learn as we go.

I guess the only way to explain how great your project looks is beginners LUCK! Thanks for your abundance of pics along the way. Your build is inspirational.
I didn't see any sign of forms in the dome. Did you do without?

Darius

[vintagemx0]

Re: The Morgan's WFO build

Yeah, better to do it right the first time. I ordered FB blanket today. I've worked with that green rockwool material before on a fireplace project. It smells just aweful when it gets a little hot - sort of like urine. I have also worked with ceramic wool blankets such as Kaowool and Cerawool, and they are definately superior. Despite the expense, I think we'll be happy just knowing it was done right.

I want to weld some angle iron structure around my chimney to insure against any stress-related issues and wrap a couple of small cables around the soldier course to ensure their integrity. If it sounds like we're not confident in our masonry skills, it's because we're not. The metal and cables are cheap insurance and will never be seen. We've never done masonry work before and don't want to have to repair any of the major structural stuff down the road...

We're still trying to decide upon the final look of the ficade. We're leaning toward a rectangular, stuccoed finish with a small decorative brick arch entry, but this will make the over-all structure look very massive. We're not too fond of the igloo or "chapel" look for our particular setting either. Still considering...

The Morgans

[dmun]

Re: The Morgan's WFO build

I beleive other memebers have said you can use rock wool insulation as long as you take the paper off the back..

Domestic fiberglass insulation (the stuff with the paper on the back) has an organic binder that burns and stinks at WFO temps. I'd stay away from it except outside your insulation envelope, and who needs it there? There is a heat resistant insulation used for firestopping, but I think it's more expensive than the refractory stuff.

[ThisOldGarageNJ]

Re: The Morgan's WFO build

Hey Morgans,
Harbor Freight has a Dry polishing kit for a 4" grinder, $ 12.99 Item # 65287 I also bought a 4"grinder for 12.99........ I had a 20% off coupon for each item as well. Sometimes they will let you use your 20% off coupon twice, You just have to pay twice.. but its worth it.. I dont think the HF kit is really going to work that well, But before I spent 125.00 For one of the better sets off ebay i wanted a little cheaper practice route, (on the back area of the oven) I can always put a plant in front of the 3 inch lip i want to practice on,

I Used the thermal blanket I dont know, but my thought would be if you did add massive vermic mixture "would you be adding thermal mass that way" I beleive other memebers have said you can use rock wool insulation as long as you take the paper off the back.. But you better read more on that,, and IF you use the thermal blanket, try to get the water soluble one, Way better for your health


Enjoy
Mark

[vintagemx0]

Re: The Morgan's WFO build

We need to start experimenting with that too Mark. What kind of tools - and where did you source them? Our lower bench, which we want to polish, is edged with angle iron along the front and the sides. I think we'll have to grind the top leading-edges of these down too.

We're approaching the dome insulation phase. I thought about just putting grimace-proportions of portland/perlite over the whole thing - say 5-6 inches. I see a lot of people put ceramic wool blanket down first, then encase it in vermiculite/portland.

Will we be dissapointed if we don't use the blanket? Could we get good results if we cover the dome 5-6 inches in perlite/portland? We're going to add blocks to the sides and build up making a more rectangular structure. I thought we could loose-fill the reamining cavity with vermiculite before putting a roof over the structure. Would this amount/type of insulation be adequate?

Thanks in advance for any thoughts...

The Morgans