Drilled (no crayon) ribbon burner

[Steamboat]

1 hour ago, Frosty said:

What they didn't explain was how they got it to break cleanly along the bottom face but I guess there have to be trade secrets eh?

Have pics of your house? 

I have a contractor friend who specializes in custom fireplaces. He has a real knack for splitting stones and getting them to break just the way he wants them to break. Sometimes I can tell how a stone will break by looking at some tell-tale smaller fractures, chips, or facets and trying to split parallel to those, but some stones have such an amorphous structure that they don't really have a specific natural cleavage that I can discern, which isn't necessarily a drawback, because those will often cooperate by splitting along and straight down under the line of wedges. I've found that the longer the wedge line and the closer together they're spaced, the more predictable the split will be, as you might expect. It's possible to place wedges on opposite sides of a stone in line with each other and going back and forth from side to side with the tapping sequence until it splits, and with luck it will split along both lines of wedges. Or you can wrap the wedge line part way or all the way around a rock if you have access. I'm not an expert at it, but I've done some pretty clean splits. Some of the granite foundations in the big old houses and mansions around here are quite impressive. Those masons knew what they were doing.

As to photos of the house restoration process, I'll plan to post a few links tomorrow so you can see a couple of "before" and "during" photos. The house is still a work in progress. Most of the heavy structural work is done and the exterior is mostly finished, but there is still a lot of interior work left to do.

Al (Steamboat)

[Ted Ewert]

Fascinating conversation about stone splitting, but I just wanted to interject a thought about burner material. 

While clay firebrick may work, why go to all the trouble of having to attach and seal it when casting is so easy and does both jobs quite well. 

As to plenum heating, my current design has the burner right on top of the forge. This one gets hot to the touch, but not close to ignition temperature. The problem I have is closing the barn doors too much, which then builds up enough back pressure to cause a burn back up into my plumbing. Seeing flames come out of the blower can be disconcerting. I know the sound now and I immediately shut the gas off and no harm done. Nevertheless, I'm a little sensitive to anything getting hot outside the forge. 

Clay might work fine for your configuration though. Give it a try. There are some high temperature sealants which might work well with the brick.

How would you attach the brick to the plenum? 

BTW, I'd like to see your foundation pics too.

Ted 

[Steamboat]

8 hours ago, Ted Ewert said:

Clay might work fine for your configuration though. Give it a try. There are some high temperature sealants which might work well with the brick.

How would you attach the brick to the plenum? 

BTW, I'd like to see your foundation pics too.

I'm not trying to promote the use of hard fire brick for a ribbon burner head, and if I ever get around to building one, it would be a while before I can get to it. If I were to construct a ribbon burner, there's a good chance that I would make a casting, since I like casting things and I could make pretty much any shape I envision, but I prefer to keep the options open and consider all ideas, since the designs and ideas that have been put forth on this forum and other sources are not necessarily exhaustive.

As to securing a hard firebrick burner head to a steel plenum, I haven't given it a lot of thought, but one possibility that just popped into my head might be to cut a groove/dado on all four sides of a brick, slide the edges of a two-part plenum into those grooves, screw the plenum halves together, and seal the grooves with refractory cement, high-temperature gasket material, or whatever. One advantage might be that you could make a few extra burner heads and quickly replace them if they are damaged. Is this a good idea? Maybe, maybe NOT, but I'm sure that with more thought, other possible approaches would emerge. As to whether or not the seal between the head and the plenum would hold up with usage, I don't know the answer to that either, but the same question can be asked about a cast-in-place burner head. You are still mating two different materials, each with its own rate and amount of expansion and contraction with heating and cooling cycles. Any differential will need to be tolerated somehow, either by the materials themselves, by the design of the burner, or both. Otherwise, cracks could develop, or the seal could loosen up. Is a cast-in-place Kast-O-Lite refractory burner head tolerant enough to maintain a seal over time? Again, I don't know, although I suspect it would depend on multiple design factors.

A good topic for someone to start would be "How is your cast ribbon burner holding up?"

A possible subject for research might be to look at commercial burners of various kinds that use some type of ceramic/refractory material for a burner head and note the ways that the burner head is secured in the burner. I don't have the time to pursue that line of research...too many other projects...but maybe someone would find it of interest.

It might be worth looking at other shapes of burners, too, such as those with round ceramic burner heads that have multiple nozzles. You might be able to achieve the same effect as a rectangular ribbon burner by using a series of, say, four cylindrical burner heads, each with multiple nozzle holes arranged in a linear array. The idea of a round burner head seems to open up the possibility of some kind of screw-down method for securing the head to a steel plenum. Maybe make a cylindrical burner head with a hat-shaped cross-section and use a threaded ring to tighten the burner head down against a gasket? Just thinking out loud...fun to speculate...

Foundation pictures coming...probably later today.

Al (Steamboat)

[Ted Ewert]

1 hour ago, Steamboat said:

It might be worth looking at other shapes of burners, too, such as those with round ceramic burner heads that have multiple nozzles. You might be able to achieve the same effect as a rectangular ribbon burner by using a series of, say, four cylindrical burner heads, each with multiple nozzle holes arranged in a linear array. 

I've been thinking the same thing. Since I installed a couple of devices to mix the gas and air better, the burner I have, although moderate in size, has become way more than I need. I have to throttle the air and gas way back to keep the temperature down in the forge. Otherwise I'm at forging temperatures or beyond. I cannot stress enough what a huge difference in efficiency is obtained by better mixing of the gas and air. I could be using a burner about a quarter of the size I have now and still be able to obtain whatever temperatures I need.

Part of the problem I'm having with flashbacks is that my blower is so choked down it's not providing much pressure. Smaller diameter holes may be necessary to help mitigate this issue. Like you mentioned, a small round burner, like a little shower head, might work just fine. Somebody built a similar type head in Frosty's ribbon burner thread. 

[Frosty]

Being able to read the bedding plane, fracture plane and cleavage plane in stone is important to using it structurally as in road cuts. Yeah, designing road cuts is a structural affair. It can make a big difference drilling cores as well but you get to where you can recognize if a barrel is getting deflected and adjust down pressure and rotation speed. 

There are almost no limits to what shape you can make a multiple outlet burner beyond making a functional burner. 

Trouble shooting commercial multiple outlet burners never talks about pressure, excess or lack of, it's almost always all about flow restrictions, once fuel air issues are addressed. 

The easy way to assure good mixing in a gun burner without having to resort to a specially designed gas jet is to make it turn a corner or two. There is or was a commercial gun burner that introduced the gas into the burner's air intake and let the impeller blades do the mixing. One of the guys in our club has one he usually uses in a melter but mounts in a brick pile forge when he needs a forge. It's the ONLY gun burner I've ever seen with the blower mounted even near the burner nozzle. Most turn at east one 90* corner from under the furnace to the nozzle. A multiple outlet burner like the one in the gas fired water heater in my last place did its mixing in the plenum. 

Blower driven air isn't effected by turbulence so long as it has a transparent path. Needing high static pressure to force the flow is indicative of an obstructed path.  Burner nozzles in this case. The system needs to be more transparent. 

I talk to and listen to the furnace guys, we even have coffee and talk about burners on occasion. They're who convinced me to NOT mess with making oil burners, especially not fuel oil burners.

Frosty The Lucky.

 

[Steamboat]

16 hours ago, Frosty said:

There are almost no limits to what shape you can make a multiple outlet burner beyond making a functional burner. 

Have pics of your house? 

I talk to and listen to the furnace guys, we even have coffee and talk about burners on occasion. They're who convinced me to NOT mess with making oil burners, especially not fuel oil burners.

Yes, Frosty, it does seem that one could get quite creative when it comes to burner shapes. As to fuel oil burners, we've been heating two houses with fuel oil for the past 10 or 11 years, and I've often looked at the oil burners and wondered how they might adapt to a forge, but that's as far as I got. Too many other projects going on to take the time to research it.

Frosty and Ted, here's a link to a few photos of our restoration-project house, including one of how it looked when we bought it, another of how it looked after most of the major structural and exterior work was done, a photo of working on the foundation, and a picture of the basement stone walls after most of the work was done on them. The basement stone walls actually look better now, after some additional pointing was done and after the mortar turned a consistent light gray. The mortar looks dark in this photo because it had recently been sprayed with water and was only partially dry. You can see that there are some pretty large stones here and there. I've got better and more recent photos somewhere, including some images of the exterior foundation, where we really made the effort to get a nice fit in the stonework, but this should give you a rough idea of the scope of work.

http://todacosa.com/campobello/images/foundation-work.jpg

Al (Steamboat)

[Frosty]

We have an oil fired boiler heating our place now and I know a couple guys who have adapted oil furnace burners to other duty, one is a ceramic kiln and one a forge. Both are not only out doors but quite a ways from their houses.

Beautiful stonework Al. Nice looking house, looks like there used to be quite a crew living there. She's going to be a beauty. Just needs a a big tree and tire swing. 

Frosty The Lucky.

[Steamboat]

On 8/9/2018 at 2:22 PM, Frosty said:

quote removed

Most people in this area heat with fuel oil, which is not cheap, but that means that there are lots of old burners that can be had for next to nothing, and sometimes free, so if I ever get to the point of building an oil-fired forge, I should be able to build one for very little expense. It's several notches down on the bucket list, but who knows? Maybe someday.

Thanks for the positive feedback on the house. I really enjoy working on old houses. This one was built somewhere between 1797 and 1805 as nearly as we can tell, and it was originally the parsonage for the town's "meeting house" (Congregational church, in this case), which was built in the 1780s.

Al (Steamboat)

[Frosty]

Talk to someone who works on oil fired boilers before you spend a lot of time building a forge, there's a lot of high temp chemistry involved between a blue oil flame and most anything it meets. 

I'd like to have old architecture around but there isn't much around here older than maybe the 1890's that didn't burn to the ground since being built. Sitka and other South East communities has old buildings but I'd rather not live in a rain forest. Good fishing though, make it worth owning a nice boat.

Frosty The Lucky.

[olfart]

Back on the original topic of drilling cast burner heads, I found out today what happens when you try to drill too close to an edge with a masonry bit.  When I get more castable mix and bust all this mess out of my burner body, the next attempt will be using either crayons or glue sticks. 

[Steamboat]

Olfart, If I were using a castable refractory, I'd probably cast the holes in place, but that's largely because I enjoy casting things and not necessarily because I would categorically rule out drilling. There are a lot of different castable materials out there and a lot of different ways to drill those materials. 

Here are several variables that can affect the outcome of drilling:

• What kind of refractory material are you drilling? Some may hold up better than others.
• Was the refractory air cured per the manufacturer's instructions? The strength of some refractories after the air cure stage may differ from others. Of course, after the air cure, the manufacturer's specified dryout schedule should be followed before actually using the refractory.
• How hard were you pushing on the bit? Usually, only light to moderate pressure is required. Let the bit design and action do most of the work.
• Were you using a drill press (preferably with the casting secured)? This can help a great deal when drilling brittle materials, as it can prevent wedging of the bit in the hole and keep holes straighter and more uniform while directing the cut/pressure straight downward.
• What drilling speed were you using? Some experimentation may be necessary to find the optimum speed for a particular drill size and material combination.
• Was it a fresh masonry bit? They usually aren't very "sharp," even when new, but a "crisp" edge is still better than one that has been significantly rounded from use.
• The size of the aggregate and the relative strength/hardness of the aggregate compared to the binder could be another factor that could affect the success of drilling.
• I assume that you did not use a hammer drill, which could tend to break delicate materials.

Since you're going to throw out the casting anyway, you might try drilling a few more holes in it and experimenting with a few of the abovementioned factors. Of course, you may still end up casting the holes, but at least you can salvage more information from the failed effort.

I've sawed Kast-O-Lite, but I haven't tried drilling Kast-O-Lite, although I might try that to see what happens. However, I've drilled holes in Mizzou, Secar 71, and a couple of other refractory materials with no problem. I've also drilled through numerous kinds of firebricks over the years with no issue, mostly from kiln and fireplace-building experience.

I hope that was of some help.

Al (Steamboat)

[olfart]

Al, I followed Wayne Coe's instructions for what he calls Ribbon Burner Castable #2.  Wayne's instructions were to leave it in the form for several days, then carefully remove the sides and bake it before removing the bottom.  I baked it at 350 for an hour, then went to 500 for another hour and a half.  That's about all the heat I could stand in the kitchen.  It sat on the kitchen table for another couple of days before I set out to drill it.  I bought the masonry bit Saturday and removed it from the package this morning.  After chucking the bit in the drill press (set at its lowest speed) and securing the burner in the drill press vise, I proceeded very gently to apply pressure.  The bit chattered in the hole somewhat, spitting out a few pieces of what I assume were aggregate, then I saw material spitting out the side of the burner where the hole had chipped out.  I'll try drilling somewhere in the middle of the block and see how that does before I break it all out.

[Steamboat]

Olfart, it does sound like at least the air-cure stage would have been complete when you drilled the casting. However, note that some refractories contain polypropylene fibers that I'm thinking could add some initial (air-cure stage) strength to the casting. During the manufacturer's specified dryout procedure (which involves considerably elevated temperatures), these polypropylene fibers would melt (or vaporize?) to add porosity to the casting. I'm guessing that you might have lost some of the early air-cure stage strength if the polypropylene fibers melted when you heated it (assuming that your refractory contained such fibers). I think that the melting point of polypropylene is somewhere in the 300s F.

Using a new bit and a drill press should have helped, and securing it so that it doesn't wobble when being drilled also helps. What kind of castable refractory did you use? That could  be a factor.

I don't know what refractory you used, but I just found a chunk of leftover Kast-O-Lite 30 from another project that has fully air dried, but has not been through the manufacturer's dryout schedule, so it still has the polypropylene fibers in it. I'll drill it and post the results in a few minutes.

Al (Steamboat)

[Steamboat]

Okay, as mentioned, I found a chunk of Kast-O-Lite 30 that was left over from an earlier project. This is some extra mixture that I had dumped into a quart-size milk carton (as you can tell from the impression of the folds in the cardboard). I drilled a few 3/8” holes in it with an old masonry bit that still had relatively good edges on the carbide tips. It drilled quite easily without cracking. This particular chunk of Kast-O-Lite had been lying around for a while and was thoroughly air dried, although it had NOT yet been through the manufacturer’s specified dryout schedule at elevated temperatures, which is why you can still see the polypropylene fibers sticking out if you enlarge the image and look closely.

Following is a photo of the exit holes on the other side. There was a bit of tear-out here and there around the edges, but not too bad. If you’re wondering about the rough appearance of this surface, when I dumped the leftover Kast-O-Lite mixture into the milk carton I didn’t bother to level the surface, so it was very uneven. Just before drilling these holes, I used some coarse sandpaper to flatten the surface because I wanted to have one flat surface to secure against a piece of plywood on the drill press table to prevent it from wobbling or shifting while drilling it. If it had been something that I wanted to keep, I would have compacted the mixture more and at least roughly leveled the surface, although I still would not have troweled it slick (the manufacturer's instructions say not to trowel it slick).

Again, you may still want to cast the holes in place rather than drill them. I think that casting the holes probably involves less risk of a problem, unless you really have the drilling procedure totally under control.

Cheers,

Al (Steamboat)

[Buzzkill]

He said he used the Castable #2 from Wayne.  I have used this as well and there definitely appeared to be fibers after casting which seem to be gone after firing.  However, that castable didn't strike me as being quite as durable as Kastolite with regard to how easily it would chip or handle impacts. It did seem to have a finer particle size and therefore I felt it had a smoother finish in the holes and on the surface than Kastolite.  I didn't do any real testing.  That's just my impression after working with both.

[Steamboat]

Good feedback, Buzzkill. I wonder, though, what "Castable #2" is made of, or comparable to. By the way, I, too, have found Kast-O-Lite 30 LI to be quite durable. I used Kast-O-Lite for collars around the front and rear portals of my gas forge, and they have been holding up very well so far. I added home-made stainless-steel needles for internal reinforcement in those castings, and I haven't seen any cracks so far. However, I think that if/when I make more castings with any kind of castable refractory, I would like to do more research on the expansion/contraction characteristics of refractories and how casting size and shape may factor into the design, with the idea of reducing internal stresses in the castings. I'm not an expert, so more research is in order. As I might have mentioned earlier, I have not yet tried casting a ribbon burner. It could be fun...maybe in a future forge project.

Al (Steamboat)

[Ted Ewert]

I have only used Kastolite for testing and drilling so I can't speak for other materials, but as mentioned, it holds up pretty well to drilling.

I just got finished recasting my air tank forge, after shortening it 4", and I used the stainless needles as added reinforcement. I don't think that the expansion coefficient of those small needles is going to have much of an impact on the casting. If it's even roughly similar to the Kastolite there should be no discernible effect.

I have yet to fire it up, although I also used the needles in some repair work on my other forge and I've had no problems. I wouldn't use them if I planned on drilling out a burner for obvious reasons, but I think they would be good at mitigating any cracking in a ribbon burner. 

[Steamboat]

Ted, what size, shape, and length of needles did you use? I've seen both ribbed and straight needles. I haven't had any issues with the needle-reinforced castings that I made (at least not so far). I used very small-diameter needles, although it's been a while and I can't recall what the measurements were.

Just a note to anyone thinking about using needle reinforcement: The commercially-available needles are so cheap that I don't recommend making one's own needles. I made my own, but I would never do that again...too much hassle to save only a few bucks. And the commercial needles can be had in a range of sizes and shapes.

Al (Steamboat)

[Ted Ewert]

They're about an inch long, ribbed and straight. I bought 2 lbs on ebay. I used about half of them on the latest casting. 

[thematrixiam]

On 7/13/2018 at 9:04 PM, Ted Ewert said:

 

This worked even better than the spinner. the flame was smooth and I had to turn down both the air pressure and the gas to get the same flame I was getting before. 

I wrote more about the details in the "Burner 101" thread if you're interested.

The burner itself works great.

 

Ted

Sorry to pull up a post so old... What this the best result you found to work Ted?

What is that blue valve? What sort of connection is that tube on the left? Is it a dual thread or something? I am trying to figure out how all connects that works and what it goes into. 

[Ted Ewert]

The perforated tube is something I made myself. It slides right into the gas valve. I have subsequently made another one with more and smaller holes. That seems to work even better. The more thoroughly you can mix the gas and air, the smoother it burns. 

I am now only using 5 ports on the ribbon burner and I can still get the forge as hot as I want. My propane usage has dropped to about a third of what I was using with all ports open, with no degradation in performance. 

I'm coming to think that most propane forges are grossly over fed. It seems that there is an optimal level of fuel for a given forge volume. More burner openings, even when turned down, waste fuel. 

I already have a modified design in mind for the next forge I build. It will have just 5 ports, or less, in the burner and they won't all be parellel. I'm going to focus the heat differently. 

Btw, the blue handle unit is a needle valve, used for fine tuning of the mixture. I highly recommend including one in your gas line. 

Ted