Two different burner types in same gas forge

[Chris C]

I'm a newbie.  Been reading everything I can find about forges.  Seems to me that a ribbon burner is great for some things and not others and that the venturi burner is in the same boat, so to speak.   Would it make any sense to install both in the same forge and just hook the propane up to the one most needed at the time?  I've not seen any forges set up that way, so it's probably a crazy idea, but I just had to ask.  I have done searches but only get hits on one burner or the other.

[jwmelvin]

I’m doing something like that with my forge. Though I wouldn’t use the distinction of Venturi vs. ribbon. To me the Venturi (aka NA, naturally aspirated) relates to air induction and is the alternative to a forced-air or blown system. The nozzle may be a jet nozzle (large single outlet) or a ribbon nozzle (array of many small outlets). 

So for my forge, I made a burner entry port large enough for a ribbon block and then made a plug for the jet nozzle to use that entry port. 

Here’s my thread if you’re interested. I don’t really know what I’m doing, so it’s all just a bunch of experiments. 

[Chris C]

Very interesting..............thanks for the link.  Stick with Frosty.................he won't lead you astray.

My questions was more about having both type burners installed in one forge at the same time and just connecting the propane via quick connectors as needed.   Lots of newbie questions running around in my old head.  Maybe one burner would be a ribbon and the other a forced air.  I've been reading too much I guess.  Seems a lot of experienced blacksmiths and knife makers have several forges in their shops for different purposes.  I'm just wondering if one forge could house more than one burner to keep from having several different forges.

[Mikey98118]

Can you; yes. Should you; probably not.

To begin with, which type of burner works best has a lot to do with forge sizes; small diameter forges get their most performance from small high-speed single flame burners. Ribbon burners are most efficient in larger diameter forges than single flame burners. Small diameter forges with ribbon burners are no slam-dunk for design issues--thus far...; that will change by and by, but we're not there yet.

[jwmelvin]

I hear what you are saying about both nozzles installed at once. I did consider that approach but decided a modular design would compromise less, at the expense of a more involved changeover. That’s and interesting point Mikey makes about one or another burner suiting a particular forge. I’m sure that is a lesson I will learn the hard way...

[D.Rotblatt]

3 hours ago, Mikey98118 said:

Small diameter forges with ribbon burners are no slam-dunk for design issues--thus far...; that will change by and by, but we're not there yet.

As it turns out, my small 1/8" hole NA ribbon burner is now running in a forge about 4.5w x  6tall x 9" long.  It's an odd shape, cross-section was a 3/5 circle with flat bottom, but I decided to shrink it to get more efficient heating from the ribbon burner and added another 1" of ceramic fiber to the sides...it's a kind of a triangular shape now with a truncated flat top where the ribbon burner is (pointing straight down).  I'd guesstimate the interior at about 200 sq inches or so (I'd have to go down to the studio to measure it to be sure).  I don't think I'd go smaller, but the burner is working fine, no back-burn issues and plenty of heat!  Tiny flame cones, less then 3/8" long so combustion is quick.  Can run the pressure down to where it doesn't pull any air, just a propane flame.  Low temps are in the 1450 range.  High is welding - 2300 or so, and I have welded in it.

2 hours ago, jwmelvin said:

modular design

The ribbon burner on the above forge is attached by 3 bolts sticking up into 3 flanges on the plenum.  I wanted a modular design too, so I did it this way so I could change the whole assembly out for a NA single or double burner or anything else (since it was an experiment, I wanted to be able do convert it back). Basically I just need to make any assembly that will fit the hole the plenum requires (2.5" x 8").  If I basically took a plenum piece, I could run a single burner into a hole on it and stuff it with ceramic fiber and swap it out for the ribbon burner.  Does that make sense?  may need to some pics if it doesn't.  Let me know.  

Dan R

[Chris C]

16 hours ago, Mikey98118 said:

Can you; yes. Should you; probably not.

To begin with, which type of burner works best has a lot to do with forge sizes; small diameter forges get their most performance from small high-speed single flame burners. Ribbon burners are most efficient in larger diameter forges than single flame burners. Small diameter forges with ribbon burners are no slam-dunk for design issues--thus far...; that will change by and by, but we're not there yet.

Well, Mikey, I'll defer to your experience.  I just thought it made sense................but hey, I"m a newbie, what do I know!  

[Mikey98118]

Your idea isn't dumb; its just too early. These guys have been doing great with ribbon burners, but having things so well nailed as to make your idea practical hasn't happen yet; may not happen for years. Getting burners to work well is easy, but finesse takes time and understanding.

[Frosty]

Nothing dumb about the idea Chris, it may not work well or may be the greatest forge since sliced bread. Now you've presented the idea and a logical reason, lets let somebody give it a try and see. Hmmmm? 

New guys come up with some terrific ideas simply because they don't know any better. Mike and I subscribe to the notion that what we know is right, probably isn't and someone will be along presently and demonstrate the fact.

Keep your first forge simple, choose one and put it to work, then make one of the others and use it. You have years to play with making a combo burner forge, no rush. Oh as a personal favor if/when you make the combo see if you can make it look like a loaf of bread and draw slices on it for me please. 

Frosty The Lucky.

[Irondragon Forge ClayWorks]

Seems to me the burner that isn't being used would over heat and deteriorate prematurely, also act as a chimney and bleed off heat from the forge.

[Frosty]

Good thought but not if they aren't mounted on the top of the forge or you choke it closed. Ribbons don't seem to chimney. 

Frosty The Lucky.

[Mikey98118]

18 hours ago, D.Rotblatt said:

As it turns out, my small 1/8" hole NA ribbon burner is now running in a forge about 4.5w x  6tall x 9" long.  It's an odd shape, cross-section was a 3/5 circle with flat bottom, but I decided to shrink it to get more efficient heating from the ribbon burner and added another 1" of ceramic fiber to the sides...it's a kind of a triangular shape now with a truncated flat top where the ribbon burner is (pointing straight down).  I'd guesstimate the interior at about 200 sq inches or so (I'd have to go down to the studio to measure it to be sure).  I don't think I'd go smaller, but the burner is working fine, no back-burn issues and plenty of heat!  Tiny flame cones, less then 3/8" long so combustion is quick.  Can run the pressure down to where it doesn't pull any air, just a propane flame.  Low temps are in the 1450 range.  High is welding - 2300 or so, and I have welded in it.

Don't know how I missed your post the first time around. It looks like your burner is his answer

Frosty is right, and this shows it.

[D.Rotblatt]

At this point I just have to see if it is as efficient as a single burner with normal nozzle.  It seems to take a bit more gas (using the same burner I used to use as an ejector) as a single nozzle burner, but it is heating up a 6-7" long area rather then a 3" spot.  I'll get to it in time...doing major construction on my house right now, so I'm playing with feather Damascus right now when I have the time.

Oh, and I measured the inside of the forge and it's around 190 cu inches.  Still a bit of a guesstamit as the shape is somewhat irregular.