b1llvance

Thank you all for the feedback. Daguy- I had read your thread before and watched the slo-mo videos. It's a great build, and thank you for sharing. The biggest reason I was looking for a different burner placement was I didn't like the idea of the face of the burner heating so much and the heat creeping back into the plenum. I know Frosty solved that problem by increasing pressure, and in all reality I most likely wouldn't be using the forge for long enough periods for it to be an issue, I was just trying to build in a structural fix. Mikey- Thanks for all of the replies and information. Originally I wasn't worried too much about flux debris, as I'm so new to this I didn't figure I'd be doing much forge welding, but I should probably assume at some point I'm going to want to give it a go. It took me a while to get the hang time/complete combustion/swirl right in my mind so I appreciate you sticking with me on it! Thursigar- Your sketch looks great. The labels are way better than the way I wrote it all out to explain it. I'm sure the other guys will chime in here but I know I've read Mikey say he's never had issues with pop rivets and bolts whereas welds can sometimes be problematic.

So I just want to make sure I'm understanding all of this right. If we are talking about a horizontal cylinder forge with a ribbon burner, and in my case I plan to make the face of the burner the same profile radius at the inner castable liner, why does burner placement matter if we are placing it at a tangent to the cylinder? If we keep it off the floor to not give up that valuable real estate and don't point it directly at the floor, say the 8 o'clock position pointing down toward the floor. Flame impingement on the wall will be exactly the same anywhere it is placed due to it being placed on a tangent. If anything I would think placing it at 4 or 8 o'clock facing up on the tangent would produce the most swirl before the flat floor had any impact on the swirl. Please don't take this as criticism of your suggestions, I still think I may be confused about the tangent placement in the first place, I'm just trying to understand the why behind the how.

Mike I’m a touch confused and I’m pretty sure it’s me and not your explanation. I get the radiant oven concept, that’s been drilled into my head reading all of these threads. But I’m confused about the burner placement. If I mount it at either 10 or 2 isn’t it going to be pointed darn near the center? And if I mount it horizontally and point it from 10 to 2 it’s still not pointing “as much upward as inward” or maybe that’s the exact definition of horizontal?

Thank you all for the quick response. A couple of quick follow up questions. Buzzkill-Any specific reason you would want to be able to change out the shell? Mikey- Thank you for the input. So if I rotated the burner to get it off of the forge floor is there any position that would have advantages over any other? Also regarding the PVC, I remember the mention of linoleum. I’m just not sure I’ll be able to get a scrap piece. Seems like everything around here is pretty thin vinyl nowadays. I was thinking of splitting the pvc in half and taking a small strip out of it. If I cut a strip to replace it, once the castable was dry I could pull the strip out, and the two (semi) half’s would have room to swing in.

Hi everyone. I've been lurking for a while now but think I'm going to give into the itch to finally build something. I've come up with a rough idea of what I'm planning, and spent a little time on Google Sketch-up trying to illustrate it. Take it easy on my Sketch-up skill, today was my first time playing with it! Anyway, I'm planning on a 3/4" NARB updraft configuration. I'd like the forge chamber to be 6" diameter not accounting for an approximate 1 inch floor. The inner castable would be 3/4" Kast-O-Lite 30, with 2x 1" layers of rigidized wool wrapped around the castable. All of that would be wrapped in 20-22 gauge sheet metal. Something like this: Due to my Sketch-up skills, everything is polygonal, instead of nice and smooth, and I also couldn't get the burner holes to be actual holes so they show as cylinders instead. My plan is to cast the tube around a piece of 6" pvc pipe with something (cardboard or wood) where the burner would be to make the opening. Then when I cast the burner, I'll use a piece of the pipe to make sure that right hand portion of the burner has the same profile at the rest of the tube. The plan is to have at least a 1/4" gap around the burner to fill with wool and allow for a little error. I'll wash the entire interior burner and all with a refractory wash and figure out doors later. I have a couple of questions.... First, what is wrong with this plan? I've read a lot on here, but not all 34 pages. I've read the NARB thread, and multiple build threads and again a lot of the burners thread but not all of it. What am I missing? I know I'm probably complicating the design more than it needs to be, but I have fun building this kind of stuff so I'm okay with that as long as it works. I like the idea of a up draft, just to keep as much heat off the burner face as possible, and I was trying to move it as far to one side to make the usable floor as wide as possible. Second, do you think there is any benefit of canting the inner most burner holes a touch toward the edge? My thought was to get the flame away from whatever metal is on the floor as much as possible and it should swirl around the tube in that configuration too. Third, Thoughts on the forge floor? I was planning on using Kast-O-Lite but I've also been reading about Bubble Alumina. In either case I think I would cast the floor separate from the tube in case I have to replace the floor for any reason. I would most likely put a thin 1/4" layer of rigidized wool between the bottom of the tube and the floor, more as a cushion to protect the tube than anything. Finally I originally had planned on adding a couple of extra burner holes, I wasn't sure if the extended length of the burner holes in the outermost row would cause extra friction and cause back pressure. I figured I'd add a couple of extra holes and then also cast a couple of plugs for them in the event that I didn't need them. Do you think that would work, or would propane leak around the plugs and cause issues? Thanks for everyone's help here. This place is such a great resource and all the people here willing to share their experience are invaluable. Bill