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Thanks Manny, glad it was helpful. The glass is Robax, I sourced my first bits from Ebay, have found a few in old woodstove doors, and now have an account with the manufacturer. I can get you some if you can't find any locally.

Patching the feed doesn't bother me, I like redoing the plaster around that area anyway, but I get your frustration. I have a few fixes for you. The easiest would be a refractory feed area, another is a metal face on the whole feed top surface with a "door" like Radek's build I linked to earlier. I've got an update video coming of my indoor heater, and one of the things I wanted to do in that video is ask you, and everyone, if you'd like to see me go another year with my existing set up or convert to a batch for comparison purposes. I have an easy way to add it onto the existing system, so it kinda applies to you since you could use the same tech to convert yours if you were interested.

My outdoor core is a batch core that has a bit in common with Peter's design but is based more on my batch experiments from a couple springs ago. I did borrow his P channel, but it has a pretty different internal layout to make the most of the window. I'm happy to share the core design if folks are interested, but it is fairly complex to put together so I haven't shared it publicly due to the complexity of the details.

Good stuff, Matt. I'm really interested in playing with a batch box. I don't think it makes sense for an indoor application for me simply because it would mean dismantling the brick work for a forward feed, I don't really have a hearth area, and I like to split my wood long (24"+), not to mention the long run of ducting... I'm just seeing smoke issues galore, though I'm saying that with no batch box experience. I may find that changing to an 8" J still doesn't meet my needs but we'll cross that bridge if we come to it. An 8" conversion is a pretty simple retrofit that just requires some work with the pick-axe and a new casting... and some warmer weather (I haven't stopped using the 6" yet this year).

Having said all that, I'm sure everyone would benefit from seeing you convert to a batch inside and make the comparison if that's something you want to do. Your videos are so helpful and it's pretty obvious that the cast core J is durable and meeting your needs.

As for glass, yeah I've had a masonry bread oven on my to-do list for over a decade now and I'm hoping this summer it gets crossed off my list. A batch box with a big firebox makes a heck of a lot of sense as it gives me a disposal site for the gnarls and crotches that can't get shoved into a J tube feed. And I'm not one to waste any heat so a little seating area with a window in the side also makes a heck of a lot of sense to go along with it. I'm imagining a Peterberg box with a small window cast into one side, and a stone surround with rocks from the yard. I'll definately hit you up if I can't find any glass locally!

Rhett, all I can say about cob is that its fascinating stuff... I absolutely LOVE IT! I can't believe this knowledge isn't common knowledge any more... the most simplest things in life can give us everything we need to keep humanity going, if only we would stick to ALL NATURAL components...

Matt, you're right, our cob mass heaters are drying from the inside out, when we fire them up, so they get to harden quicker than if just left to dry, except if you live in a very dry area, which I don't, btw.

And the things you can make and do with cob is really cool, like building pizza ovens, cottages, outhouses... even add to an existing home..
I plan on using cob to patch up some drafty holes in the chicken coop this summer, even thinking of building a small rocketstove for them as well, so they'll have it nice and warm during the real cold days of winter, but that's another big project.

I've gone and ordered me a book on cobbing, in hopes of getting more tips and ideas. Oh, besides, real good clay will also have a detoxing effect on you, so its actually healthy to go out and play with cob! Hope you've already had the opportunity, seeing that your post is from a few weeks ago...

Cob Away!
Aldi

I've got my daughter making adobe bricks that I will use for my shop heater. I plan on cobbing around them but using them for the bulk of the mass. It's just a good way to take advantage of the summer sun here to get a dry structure up fast. And while they won't allow me to do everything I need to do in terms of organic shapes and air-tight chases and so forth, they're a big step in that direction and something I can have my daughter do with little direction. Since these don't have to hold up a roof if she gets the sand/clay ratios a little off no worries on that front. Can't wait to start cobbing these things in and seeing it take shape. I just need to decide between a shop-made rectilinear radiator a la Matt's Walker stove vs barrels.

I'm glad to hear that your daughter is also involved, Rhett. I have found it very satisfying to look at something and know that I was part of making it happen. Hopefully your daughter will get the same glow.