Announcement

Collapse
No announcement yet.

33 inch cast homebrew Kent

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #16
    That’s a bit of a pity, free is always best. When crushing insulating firebrick a similar thing happens. As it’s the air that does the insulating the dust is normally not included in the mix, but you can use it elsewhere as you suggest.
    Don’t bother crushing the dense firebrick for addition to mortar as anything larger than 0.5mm is too coarse for mortar. Sand is cheap enough.
    Kindled with zeal and fired with passion.

    Comment


    • #17
      Base insulation done, 100mm of thermalites with 50mm of pumice on top. Just waiting for it to dry.

      Comment


      • #18
        Got some more work done today, floor bricks are down, levelled on the pumice dust, a by product of crushing the pumice, seemed a shame to waste it.
        Thermal/expansion break between the oven and gallery floor, angle cut from bottom of bricks and filled with pumice.
        Sand dome done, this was surprisingly easy, there's a post in the centre with a screw in the top at the correct height for the dome. After screwing it in I drilled a hole in the head of the screw. I then made a half former from plywood and put a small headed nail in the top centre which located in the hole in the screw. It was then simple to use the form to shape the sand dome.
        Got the newspaper over the sand, what a nightmare! Got most of it covered in 50mm wide strips but there was quite a few ripples and the wind kept blowing strips up. So then started putting patches over the strips, this was much easier and covered and smoothed out the ripples. If I had to do it again I'd build a spiders web of strips and then use patches.
        I was just getting everything ready to cast the dome when I had a phone call from my 5 year old Granddaughter with a medical emergency that only Grandad could sort out, so I covered the paper with good old flour and water hoping it'll still be there in the morning.
        Had a baby robin that turned up wanting to help, or it may have been for worms? I'm not sure.
        david s With the poly fibres, do you just chuck them in and mix, or do you spend hours separating them?

        I also manage to win some body soluble 25mm blanket on ebay, won't have to buy the extra perlite now, so by the time I knock the price of that off it only worked out about 40 quid, so won't now be using rockwool, I think have enough to put three layers on, 75mm.

        Comment


        • #19
          Excellent work. How did theflour and water trick go with the newspaper? It really is a pain doing it if it’s windy.
          I add the fibres when adding the water to the mix. Doing it in a barrow is easier than a mixer because it’s easier to judge the consistency and inspect the mix for fibre dispersal. I do pull them apart a bit as I add them. If you have an assistant it’s a really good job for them to pull them apart and add them as you mix. You do need to mix them in for longer than you’d think to avoid clumps.
          You won’t regret the ceramic blanket choice over rockwool. The little you’d save is more than offset by the CFB being firmer and easier to cut and fit, as well as being far better to vermicrete over.
          Cute bird, even if he is a flour thief.
          Kindled with zeal and fired with passion.

          Comment


          • #20
            [QUOTE=david s;n426615]Excellent work. How did the flour and water trick go with the newspaper? It really is a pain doing it if it’s windy.

            Did the cast yesterday morning, the flour on the paper worked really well, it didn't move around at all, I would definitely do it the same way if I did another one.
            Hit a couple of small snags though.
            Firstly I thought I'd mix the homebrew dry in the mixer then tip out a bucket full at a time as required and mix the water in by hand. Great idea on paper.
            Because of the lime content I was PPE'd up to the hilt, coveralls, goggles, professional dust mask, 2 pairs of gloves, part of my job when I had one was taking suspected asbestos samples to send off for testing, all the equipment, including all the disposable protective gear, came in box so I used one of the kits, I was ready for anything.
            What I wasn't ready for was the amount of lime dust that the mixer threw into the air, no problem I thought, I'm invincible, then I got a tap on my butt, I looked round and two of my grandsons had arrived through the back gate, 3 and 4, and had run down the garden to see the snow. so in a moment of panic I threw a bucket of water in the mixer which thankfully stopped the dust straight away.
            Trouble was I was now committed to using the mixer, there was 72 litres of dry homebrew in there, no problem for the mixer dry, but seriously overloaded once water was added.
            Luckily, it coped but it was struggling especially as I wanted to mix it for a long time. Second load was smaller so not an issue.
            What a pig to clean out when I'd finished that homebrew was.
            That was snag one.
            Using the home brew was a doddle, I used a small gauging trowel to apply it and a shaped piece of wood for depth, working my way round in 3 bands, but spreading, like thickly buttering bread, a thin layer then immediately building it out to 60mm, really making sure that thin layer was firmly pushed against the paper, hopefully I'll have no voids to fill, which brings me to my other snag.
            I was just over half a bucket short for finishing the gallery which I mixed by hand, trouble is I didn't have enough clay to do a proper 3,1,1,1 it's probably 3,1,1,1/2.
            I think it'll be ok, it's just part of the smoke chamber, looks ok this morning.
            So if I do have any voids to fill I have no clay.
            Whilst doing it I had a thought!!!!
            You loose some heat via the gallery, some people cast it separately and incorporate a small thermal break, David you cast your smoke chamber separately as well and one of your suggestions for first time builders is to make the sides of the gallery in fire brick and sit the smoke chamber on the top.
            Is there any reason that when casting the smoke chamber you couldn't replace the sand element of the homebrew with perlite?
            The sides of the gallery have to be tough to take punishment but the top doesn't get touched, would this stop some heat loss? is it worth considering? or am I talking BS?
            Last edited by hughjamton; 07-29-2020, 12:58 PM.

            Comment


            • #21
              Bit late now, but I held a large foam tile over the mixer mouth when doing my dry mix.... Removed it when I turned the mixer off....

              Comment


              • #22
                Good job. Replacing some sand with perlite at the top of the gallery to reduce its thermal mass is a pretty good idea, but only go as far as replacing half the sand or it will make the casting there too weak. I think you’ll have to get more clay for the homebrew mix for filling the voids. It is also useful to add some to the lean vermicrete mix over the blanket to help make it more workable. I hope you added some polypropylene fibres to the homebrew.
                Last edited by david s; 07-27-2020, 12:10 PM.
                Kindled with zeal and fired with passion.

                Comment


                • #23
                  Originally posted by Nick J C View Post
                  Bit late now, but I held a large foam tile over the mixer mouth when doing my dry mix.... Removed it when I turned the mixer off....
                  Never thought of that one.

                  Comment


                  • #24
                    Originally posted by david s View Post
                    Good job. Replacing some sand with perlite at the top of the gallery to reduce its thermal mass is a pretty good idea, but only go as far as replacing half the sand or it will make the casting there too weak. I think you’ll have to get more clay for the homebrew mix for filling the voids. It is also useful to add some to the lean vermicrete mix over the blanket to help make it more workable. I hope you added some polypropylene fibres to the homebrew.
                    Yes to the polypropylene fibres.
                    I've already done my gallery, I had the idea too late, next time maybe (my step daughter has put in her order for one today)
                    The annoying thing with buying more clay is the cost of the postage, it's more than the clay, I can't help feeling ripped off.
                    I'm going to use pumice over the blanket, I think I've got enough crushed now for one and a half inches.

                    Comment


                    • #25
                      Looks like really good progress. Running out of materials is so frustrating isn’t it! I’ve had it a few times now - definitely could have been a few weeks further ahead if not.

                      Good luck for the next steps
                      My cast oven build thread

                      https://community.fornobravo.com/for...-castable-dome

                      Comment


                      • #26
                        Ok, if you only need a little there should be plenty under your topsoil.
                        dig a little, dry crush and sieve it.
                        Or if you have a local potter you could get a little from them.
                        Kindled with zeal and fired with passion.

                        Comment


                        • #27
                          Originally posted by david s View Post
                          Ok, if you only need a little there should be plenty under your topsoil.
                          dig a little, dry crush and sieve it.
                          Or if you have a local potter you could get a little from them.
                          Removed the gallery mould today and the sand from the dome, don't seem to remember putting that much sand in it!
                          I was really pleased to see there was no holes or voids in either the gallery or the dome that I thought needed filling, I was particularly pleased with the dome, just as well really as being short of arm and body I couldn't quite reach the back of the dome. but I personally put that down to my manly broad shoulders.Although I've always said "I'm not a gynaecologist, but I'll take a look" I just cannot reach the back of the oven to get the last bits of paper out, that's going to be a job for my son.
                          However, whilst taking out the sand from the dome I managed to give the door rebate an almighty wack with my trowel and took a chunk out at the top, about the size of a finger nail.
                          Oh dear, what a shame, I thought, or in old fashioned English, "Bollocks, I've got no effing clay" Anyway, on checking the sack the clay came in and giving it a good shake, I managed to collect enough dust for about a handful of homebrew, more than I needed.
                          I repaired the damage but had loads of the mix left so I started trying to fill any tiny holes in the gallery. I soon gave up deciding I was wasting my time as they were so small I don't think the home brew would stay put.
                          I then thought I'd round the internal corners inside the gallery, done, still some left, checked the level where the flue pipe would sit, bloody good job I did.
                          She's back under her wet blanket now having a rest.

                          The white in the picture is the flour.
                          Last edited by hughjamton; 07-29-2020, 01:04 PM.

                          Comment


                          • #28
                            Originally posted by Mullster View Post
                            Looks like really good progress. Running out of materials is so frustrating isn’t it! I’ve had it a few times now - definitely could have been a few weeks further ahead if not.

                            Good luck for the next steps
                            Thanks Mullster, I've read your thread.
                            How's yours holding up after the repairs to the gallery?

                            Comment


                            • #29
                              Originally posted by hughjamton View Post

                              Thanks Mullster, I've read your thread.
                              How's yours holding up after the repairs to the gallery?
                              It seems ok - but the real test will come when I get to the curing fires in another week or so - really have my fingers crossed!
                              My cast oven build thread

                              https://community.fornobravo.com/for...-castable-dome

                              Comment


                              • #30
                                Installed the flue today using
                                david s

                                method. Slightly different, I did the 8 inches of vermicrete at 5/1 but the wind is quite strong and there's no immediate strength to the vermicrete, and I was worried it might shake loose, so I've gone around it with a further coat of pumice "dust" again at 5/1. Pumice seems to "set" almost immediately and it's now very firm, but the vermicrete is inside, hopefully to take up any expansion of the flue.
                                The dome seems to be completely dry on inspection, I don't for one moment think it is.
                                I have a small de-humidifier that I use in my bar in the garden to keep it dry in the winter for the TV, so I've put it in the oven and sealed the inner doorway. It's not a powerful de- humidifier, but it will be interesting to see what it can pull out of the wall that looks dry.
                                The TV Ariel in the picture is for my bar.

                                Comment

                                Working...
                                X