Is fireclay necessary?

[biondoli]

Re: Is fireclay necessary?

Simon,
you mentioned that you found fire cement..is it a kind of refractory mortar? If so then you don't need fire clay....I did laied down the bricks on the ceramic boards ans didn't use fire clay for any other scope.

[james]

Re: Is fireclay necessary?

Ciao Carlo,

Fire clay makes traditional Portland cement mortar more resilient to heat cycles (heat up and cool down). It does not make refractory mortar, which is calcium aluminate based -- and a different animal.

If you are controlling costs, fire clay added to a Portland cement mix is the right way to go.
James

[biondoli]

Re: Is fireclay necessary?

James I think there is misunderstanding...I was answering Simon's note...
but your note is creating some doubts in my mind now...
I am using heat stop 50 which is a refractory cement I think is the same like remix...even in terms of cost
Am I doing anything wrong?
And I have (should have) no need for fire clay as well...right?

[james]

Re: Is fireclay necessary?

Didn't mean to stir up the pot. Heat Stop 50 is a true refractory mortar, like Refmix -- of course I like Refmix better. :-), and it is a good alternative.

James

[rafv]

Re: Is fireclay necessary?

Wow, did not know expensive fire clay was going to be. I was hoping to use Long&Somerville but not at those prices. Purimachos do Kos Heatproof Mortar in 10kg tubs. This is refractory cement for laying fire bricks. Plumbing Supplies : MyTub Ltd have it for sale at ?9.66 but they will only sell you 12 Tubs at a time plus ?20 delivery. www.fireplaceproducts.info have it for ?16.

[SimonWoodfield]

Re: Is fireclay necessary?

rafv,
This was really my question I guess, can I use something else. Is KOS heatproof mortar a sutiable alternative? Purimachos are my first choice at the moment because although their firebricks are 1.28 as opposed to 1.05 as the cheapest I have found, they are local to me, and I could go and pick them up and avoid the delivery charges.
If this is a suitable alternative, then I will be off to get some in the morning!!

I have found fireclay now for 0.38/kilo in 25kg bags, but again, delivery is a big factor in the price and they are in Yorkshire, too far for me to collect.

Thanks to all those suggesting where to look. I was looking at the standard places in the UK, builders yards and DIY etc but they have no clue about it and the refractory places don't tend to have very comprehensive web sites!

[Frances]

Re: Is fireclay necessary?

Don't worry, a lot of us have been through this bit...

It seems that everybody can just take one trip to the local DIY shop for all their oven materials except for you - I know that's what it felt like for me anyway. I'm sure you'll get there! Hey, it's all part of the fun, right?

[SimonWoodfield]

Re: Is fireclay necessary?

I am guessing fun must have a different meaning in Switzerland!!
I am calming down a bit now I have found that there is some available, everybody I spoke to this morning seemed to be saying that there used to be plenty of it, but due to closing of most of the mines over here, that it is now in short supply. Even now I have found it, the costs are prohibitive, mainly due to transport. I was just hoping that an alternative was available that is more mainstream and hopefully cheaper. A potter supplier I spoke to said that there are alternatives. Does anybody know how hot it gets in there??
And as I said earlier, Tom Jaine suggests that it isn't necessary at all.

[james]

Re: Is fireclay necessary?

The Tom Jaine book was written in 1996 when there was very little (nothing?) in English about wood-fired ovens. I read it after I had built my first Scott oven, and did not find it very inspiring. Bread Builders was published in 1999. Since that time we have learned a great deal about wood-fired ovens, both in construction and cooking. Happily, we are now pointing in a much better direction.

I think it would be worth the effort and investment if you could find fire clay. It should not be expensive, and it will help with your oven performance and longevity. Straight portland-based mortar will start to crack and give way pretty quickly.

James

[rafv]

Re: Is fireclay necessary?

Simon,
I contacted Purimachos about Kos Heatproof Mortar and they said that it would be ideal for building the dome. It says 'Refractory Mortar' on the tub so I would think that it is as close to Refmix that FB sell (not over here). I would not use it on the hearth bricks though.
I am interested in your source of fire clay, Yorkshire is not that far away for me.

[SimonWoodfield]

Re: Is fireclay necessary?

rafv,

Any thoughts as to what I could use for the hearth bricks?


Fireclay source


Yorkshire Refractory Products Limited
Unit 9, Leebridge Ind. Est
Leebridge Road
Halifax
West Yorkshire
HX3 5HE
U.K.
Tel:+44(0) 1422-353344
Fax:+44(0) 1422-353366
E-mail:sales@yrpl.com
Web:YRPL Homepage

They offered 140 2.5" bricks at 1.05 each and 4 bags of fireclay at 0.38/kg

[JFS_Cheshire]

Re: Is fireclay necessary?

Hi everyone.

I bought my firebricks from Dudley Designs (DUDLEY DESIGNS)
They also sold fireclay so I ordered 3 bags from them, about ?10 each.

In the end I only used 2 so I have one going spare if anyone can collect from chester.

Hope this helps.

Jon

[SimonWoodfield]

Re: Is fireclay necessary?

Jon,
Useful to get an idea as to how much I would need, I didn't see this anywhere and was going to order 4! I checked Duldley Designs out for bricks, but again, with delivery, they were quite expensive

[Carl]

Re: Is fireclay necessary?

I bought my fireclay from clayman supplies in Chichester. Their delivery prices were very reasonable for me. Link is here. I also bought the grog I used from the same place, and the sodium silicate.

Carl

[dmun]

Re: Is fireclay necessary?

Carl,

Did you use water glass (sodium silicate) in your mortar? Did you tell us about it?