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View Full Version : 16" Glory hole brick archway... 4.5" wide- really?


Andrew Brott
09-23-2011, 02:06 PM
Due to the sudden collapse of the non profit I used to blow glass at; I am in a mad dash build a hot shop on a limited budget.
Need to build a glory hole ASAP-
My design is what I feel to very tradition/conventional..
- 16" ID of 2800 IFB.
- 1.5" (or 2") of wet compacted frax
- to a 12 gauge steel cylinder
- Pine ridge burner/blower and safety system.
- Kast-to-light back end, + retaining ring to make a 14" wide by 27" long ID"
- 2 Kast-to-light 30 doors-
2 big questions:
#1-
Are there suppliers of 2800 IFB brick Archways with bricks cut on the 3" (or 2.5" for standard) side of the brick, and NOT on the 4.5 side as with more readily available archway bricks?
Could cut 16- 3" per row at 22.5 degrees to make 16" id arch myself, but to save on time, mess, and damage to my wet saw (yes- that's is how I would do them- to limit dust) I want to buy them. (?)
My friends at Larkin refractory can do this for me, but as they pointed out- why not just us the 4.5" wide bricks they have in stock?
So question #2-
Should I build a glory hole using a 4.5" ring of IFB?
Call me stupid (yes I am)- but I am not used to seeing, using, or building glory holes with that thick of a IFB ring...
+ My math for a 4.5" Archway brick makes me need a 28.5" wide steel cylinder for a 14" ID glory hole...
My math= 16" ID of ring + 9" (4.5x2) of IFB + 3" (1.5x 2) of frax = 28 wide + .125 for thickness of steel makes final OD of steel cylinder roughly 28.5"
Spoke to Tom at Pine Ridge (my burner/blower) he said his burner works with up to 6" of insulation- but 28.5" wide still seems stupid huge to me, when I would have preferred more like 25" wide using brick cut on 3" side?...

But as time = money, and when you price out both options (+added steel) the costs are close enough for me consider the 4.5?...
Any suggestions and or input would be greatly appreciated.
Best and thanks,
Andy Brott
andy@brottworks.com

Jeff Thompson
09-23-2011, 02:49 PM
OK, you are right, glory holes are not built with 4.5" brick thickness because it will add too much mass to the whole unit. Its a delicate balance of material, density, heat and time to heat up. This same dimension (interior) built with 4.5" rather that 3" will take much longer to heat up in the morning. But will hold heat very long with the doors open. But 3" brick glory already holds plenty of heat for long door-open periods. Also I think that fiber blanket is a much better insulator, so the "quicker" you can get the heat to interact with the blanket is better: so when I built a 9" glory hole I first cut all my bricks in half down the long way so the wall thickness is 1.5"

I have a 17" glory like this and if I were to do it again I would make the back wall from 2800 bricks, rather that castable. The castable takes forever to really heat up. The old Spial Arts glory holes were built with brick in the back, for whatever thats worth.

Andrew Brott
09-23-2011, 03:29 PM
THANK YOU!!!!!!!!!!!!!!!!
Now I see the logic and your frax to brick ratio makes total sense!!!!!!!
Makes me wonder if I should use 2.5 " inch brick and X for frax?
What's that golden ratio...
+ too much frax could be bad ? Not an expert (far from) but is not IFB supposed to be run up to 80% of what the rating is?
So if 2800 x .20 = 560 then 2800- 560= 2240) I should never run a 2800IBF glory hole above 2240?
I know 2240f is hotter than I want to be, but I wonder if I want to increase my frax and use 3000IfB? I only want to build this once, + need to find grog for the kitty litter bottom, saw my mentor Jim Engebretson posted something on this (cheaper and better) a while back need to find the same.
Many thanks,
ANdy

Rahman Anderson
09-23-2011, 03:36 PM
I suggest a retention ring that is 1/3 the interior diameter. And here here to avoiding castable in the back.

Pete VanderLaan
09-23-2011, 07:46 PM
85 percent is the considered norm. 2800F x 85%= 2380F which is quite hot. You can run hotter. It's just better to not sustain things like 2450F or, the bricks do spall.

Too many gloryholes get built out of 2600F brick and they will fail in a few years.
Grog is available at any decent pottery supply house. I just throw a piece of fiber down there and change it once a year.

Jeff Thompson
09-23-2011, 08:14 PM
I only want to build this once,


You'll be happy with 2800's. My 28's are nearing 10 years old and still have lots of life.

Yes, I believe there can be too much frax. There are different ways to look at this problem, but the way I see it is like this: after you exceed the "golden" amount of frax it begins to become a heat sink, rather than an insulator. A contributor to this is that once you pass the golden point, you increase the exterior surface area= more surface to radiate off heat.

Jeff Thompson
09-23-2011, 08:23 PM
Makes me wonder if I should use 2.5 " inch brick


So the other side of this thermal-dynamic coin is strength and durability. I was very happy to use 3" bricks in my 17" and would do it again. Yes, you could get away with 2.5's, especially if your brick work is clean and all your angles are tight.

As for ammount of frax, I think convention wisdom is on track at around 3 inches thick.

Jordan Kube
09-24-2011, 04:44 AM
2.5" brick works fantastic. I would recommend the Spiral Arts burners from Wet Dog. You'll get even heat in the gloryhole with the option to spot heat. Not possible with ribbon burners.

Pete VanderLaan
09-24-2011, 06:58 AM
The frax versus mass is a dead trade off. If you do go with mass, which I prefer, you will need a lot of burner to get up to temperature quickly. Too much frax gets you hot quickly but you lose it all when the door is open.

I agree about avoiding the castables and prefer 2800 brick. While castables are shock tolerant, that only goes so far and they will spall if they aren't thick enough. Brick with mortar really seem to do well. Castables are for doors and retention rings. Then use Kast-o-lite 30.

Andrew Brott
09-24-2011, 11:03 AM
I will tell y'all- what I just told my wife.
Damn I'm (we are) blessed to have such a great resource and sounding board.
As always many thanks to Peter and the rest of y'all.
Form follows funtion- so its fun to see and know how this golden frax to mass ratio has evolved our modern glory hole to look a certain way;
Could try to define (and fail) to be witty and say it's 1-2-3/3-2-1...
or
3" of 2800 brick
2" of frax
.125" of steel
but I don't think that's right.
Think it's more like 2.5-2.5-.125 - and or even 3-3-.125
Can't go wrong with either.
+ another big "here here" as to a soft brick back wall.
But whats behind it?
tempted to use the extra INS board I have on hand + easy to cut circle.
But fact is- frax is, the stuff that fluffs da heat back ya.
So I will probably use it, but wet it first.
May even leave a weep hole in the bottom of my metal drum to let water out as I compact the frax ring.
Very spoiled to have a Hardware store across the street with a fork lift...www.thenewfreret.com - no engine hoist required YEAH!!!

The folks (Jim) at Larkin Refractory also said they had Frax in a batting or fluff like "cotton candy" state.
Sounds itchy cool- don' plan to use (could make some nice fire rated pillows...) unless it gives the same frax performance with out the need to be cut.
Rahman Anderson I suggest a retention ring that is 1/3 the interior diameter.
Not sure what you mean?
Was planning to do my outside Kast-to-lite- 30 ring 1.5" thick with a 14" id hole for the 16" archway brick.
so it has 1" that sticks beyond inside brick.

Talked to the Guru Mr Dudley Gibberson a few weeks back, need to re-buy his book (both Koss and I lost a copy to hungry water) + will read what Henry has in his & could, should, and will eventually speak with Eddie (wetdog), just need to get this done and he has moved on to greener pastures...
Promise to shoot and post pictures on what Johnny Watson and I build.
Thanks,
Andy

Andrew Brott
09-24-2011, 11:33 AM
side note;
was with my good friend and New Orleans Chef John Rowland last eve, so which one of u did he meet this summer?...
AB

Scott Benefield
09-24-2011, 12:43 PM
Is that the New Orleans School of GlassWorks that shut its doors? Just curious.

Jeff Thompson
09-24-2011, 01:13 PM
Not sure what you mean?
Was planning to do my outside Kast-to-lite- 30 ring 1.5" thick with a 14" id hole for the 16" archway brick.
so it has 1" that sticks beyond inside brick.



Glad to help! Glad someone understands me!

What he's saying is make the ring bigger. Like this: 14" opening and 2" retention ring on both sides = 18" interior diameter. On my 17"'er I have 1.5" retention ring, so interior diameter is 20", but I cheated myself and should've had a minimum of 2". Dudly' book has some good illustrations of the effect the heat retention ring has on the heat. Its super tough when building one of these to give yoursefl extra retention ring, becasue it feels like you're making your opening smaller, or wasting interior space, or something! But the reality becomes that when you're really maxing out that 14" hole, you'll be really glad to have 18-19" interior to move the piece around in the hole. According to Rahmans formula, the retention ring should be 4.6 inches, divide by two = 2.3 inches on each side.

Use packed fiber to back-up the soft-brick back wall. That ins board is for kiln back-up, glory will get too hot. Use little bits of soft brick to make pedestals to support the soft-brick back-wall, espciallty around the perimeter, as you will add a lot of weight there as you build the sidewalls.

Yes, leave a weep hole (or 3). Glass Notes speaks specically about weep holes.

The cotton candy blanket sounds awesome! You will elimate the step of cutting the blanket into strips. Work everything wet! Cut the bricks wet, assemble the bricks wet, not dripping, just moist. Pack the blanket wet. Make sure there is some moisture in the bricks and fiber when you go to cast the retention ring.

I would probably go with the Spiral Arts burner next time I make a glory hole. I know a glassblower that has approx 14" glory hole and its rigged with the smaller size pine ridge, and man that burner has to CRANK to get that hole hot. So hot, in fact, that is has obliterated the soft brick on the opposing side. These pine ridge burners in fact need to be mounted in a fashion that wraps the flame around the interior of the glory, like is recommended for the round burners. The instructions from PR says to mount them with the burner pointed at the middle of the hole. That has some problems for a glass artist like me, but probably not for most folks. The problem for me (sculptor) is that the glass is getting blasted by the direct flame, over 3000 degrees. It melts the details away. If all you make is vessels or paperweight, it prob. doesn't matter.

Pryor&Giggy phlocast 30 is an outstanding product for doors and retention rings. Kastolite 30 is the gold-standard around here, tho. I think Mr. Stadelman was using phlocast 30.

Andrew Brott
09-24-2011, 03:15 PM
Scott,
The New Orleans School Of Glassworks is still open-
and it's http://www.nocgi.org/ that closing, so it's another kick in the teeth on top of the Louisiana Artworks disaster...
They never even opened, and are now in receivership with the City Of New Orleans...
http://www.nola.com/arts/index.ssf/2011/09/what_is_the_status_of_louisian.html

With all the moneys they raised and spent on "our" behalf + all the $ myself, Josh C, Julie J, Charity P., Devon F, and many many other spent renting time at NOCGI- I'm too heartsick to say anything beyond a big thank you for yours, and everybody's support for us post K.
All this must sound horrific- it is, + makes the New Orleans Glass scene look like a bunch of Turd Burgelers (I am), but there is light at the end of the tunnel and it's not a train...
May have good news and announcements soon (?).
And if even this fails, our region is still stacked with people like Mark Rausenbaum
http://www.rosetreeglass.com/
who won't toot his own horn here, but lets just say he is the real F****### DEAL!!!
+ with Mitchel, Jim, Mark, Paulo, Gerald, Jenny, Drake, Gene, Steve, all of Tulane, and even yourself on occasions + the many, many, others who still work glass here- will be fine...
Side Note:- The Craft Community is blessed to have CERF-
Y'all may think and see what they do as small, but I would not be building my own hot shop now if it were not for theirs and many others support post K.
I came very close to staying at:
http://www.chicagohotglass.com/
or returning farther north to:
http://www.mnglassart.org/
And I know Gene Koss was close to the same.
Those were some dark days, and I can't believe how strong we are now....
Please give to http://www.craftemergency.org/
Best,
Andy

p.s. The other reason I can build a hot shop is zoning, we were very lucky x 1000 to have bought on Freret Street pre-k- (could never afford now- http://thenewfreret.com/) + even luckier we had a AC zoning overlay added in 2008 to spur new development. With help from planning experts, the correct verbiage was added to allow for hot shops as Artist Studio's- rare in NOLA except for LD (light industrial).
So I can now build one here...
http://www.glassartists.org/Gal37447_BrottWorks_New_Studio.asp
If there artist/crafts people in other cities/regions who ever get the same opportunity- feel free to contact me at www.brottworks.com and I will try to find and provide what they wrote.

Josh Bernbaum
09-25-2011, 07:26 PM
Don't skimp on the retention ring, the more you "retain" means the less heat you let spill out when you open all the doors.

Use at least 3" of frax behind bricks, drill some "steam holes" in the can but only wet it as much as needed to keep dust down. I use the mist feature on a hose spray nozzle.

If you recuperate it properly you'll save a shitload of fuel. I know that's not the theme of this thread but it should be for any talk about GH's these days.

Pete VanderLaan
09-26-2011, 05:47 AM
They do sell lubed fiber you know. Use zero water and it really packs well.

Andrew Brott
09-26-2011, 10:05 AM
Josh, Jeff, Peter, and all THANKS!!!!
going to sit and draw this today + start work + finish this week- very lucky to have machine shop close that can turn/complete from 3 hrs of my order...
Plan to use 2.5" 2800 Brick
14" opening
18" interior
3" frax
Jim at Larkin advised me all Frax is lubed in some fashion- and I should Try the "H.P.- Bulk" Frax for 3" ring- no need to cut/wet- just stuff pack.
Wish I had the time and cash to recuperate heat-maybe later.
Love the pictures Ben Long posted@
https://picasaweb.google.com/112582995510904193943/LargeGloryHoleBuild?authkey=Gv1sRgCNq68MCA0azF9wE&feat=email
Take note of the brick in castable for back wall...
Interesting...
but plan to lay brick flat, build, mortar, cut out 18" circle- and then temporarily strap to get set in place- then brick and frax stuffed.
Makes me think of-
http://en.wikipedia.org/wiki/Turducken

With only Johnny Watson and me using this (should be no drips, runs or errors...), may cast retention ring in same permanent fashion as Ben Long did - or am I making a huge mistake and need to spend some extra time at the machine shop and make it replaceable + pre fire it + glory hole doors?
Gotta run - tooo much to do with electrician for Tuesday.
Thanks to everybody-
AB

Jeff Thompson
09-26-2011, 10:44 AM
.
but plan to lay brick flat, build, mortar, cut out 18" circle-

Where will the bricks sit? If you're using 2.5" bricks you must add 5 inches to the dia. of the back wall, so there is a place for the bricks.

It seems like ALOT of extra time to make the retention ring removable. I wouldn't bother... I think the retention ring will last longer than the 28's anyways.

Andrew Brott
09-26-2011, 10:55 AM
sorry-
that 18" is just the very back ring wall done as brick not castolite 30
18" is the id of the inner ring
then 2.5 brick or 5"
then 3" frax
18"+5"+6"= 29"
So would order a 12 gauge rolled steel tube that is 29-1/4" wide.
Ab

Jeff Thompson
09-26-2011, 11:00 AM
What I'm trying to say is that the softbrick sidewalls sit on the softbrick backwall.

Andrew Brott
09-26-2011, 11:09 AM
Ah...
will do-
after I order book from Dudley right NOW!!!
Ab

Jeff Thompson
09-26-2011, 11:36 AM
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like this, bro (only showing one sidewall)

Hugh Jenkins
09-26-2011, 01:34 PM
[QUOTE=Josh Bernbaum;99900

If you recuperate it properly you'll save a shitload of fuel. I know that's not the theme of this thread but it should be for any talk about GH's these days.[/QUOTE]

Josh has it right. The glory hole will be a big energy drain in a very short time.

It is not impossible, in fact it is very possible, to retrofit a recuperator, but it means you are invested in a burner system that will be removed, and have some shut down time when that time comes.

Consider that the glory hole you are about to build could run on 1/2 the fuel if recuperated, and ask around for what it could use, even with a ribbon burner, and calculate the savings for the fuel in your area.

As you might suspect, I would recommend recuperating from the get go.

Andrew Brott
09-26-2011, 08:45 PM
I'm looking into this, a we bit overwhelmed...
Oh boy...
Logic says I'm stupid NOT to recuperate-
but stupid is, as stupid does; and as arrogant fool speaking in turd (3rd) person, I claim to be a kiln fired first & hot shop second glass Artist; so we had planed to continue to renting time to meet our hot glass needs
& invest in solar and VAWT's http://www.tangarie.com/files/GaleT1-R15-Specifications.pdf
for our new studio/home-
http://www.glassartists.org/Gal37447_BrottWorks_New_Studio.asp
With a combined 80% tax cred/cash from State (La.) and Feds, would get great ROI (much like a recuperator?.. May need to bust out a LEED calculator..)
Then www.nocgi.org closed, so need to spend that $ to hot shop...
Still will solar/vawt eventually, as to recuperate? Need to look that up- and or somebody please add/link here
Have seen it on Eddie's furnaces, can't be that hard to do for a GH?
Thanks to everyone,
Andy

Andrew Brott
09-26-2011, 09:29 PM
Jeff-
can see non ya picks...
sorry-
AB
The back wall is the last thing I need to figure out before I order my tube rolled/fabbed (with maritime industry 1/2 mile away- I can order and have it done to pick up in 3 hrs- super cool...)
Should I do a 2.5 side of brick on 2.5 (3") of layer of frax for 5" thick?
so back wall is 5" thick?
If so, how wide should that brick back wall be inside a 29" wide tube with 18"Id x 23"od brick archway?
All the way to 23"?
Will mortar brick back wall, but don't want to be slammin frax against it-
so I am going to plan to do at 23" wide at bottom center.
If this is correct- my steel tube is 29.25" wide and 33.75" long
as 3 offset rows of 9" brick are 27" long.
then 1.75" retention ring-
so- 5"+27"+1.75"= 33.75" long tube...
- I can over-complicate nuttin, so I'm also puttin this on wheels that lock.
http://www.steelcasterstore.com/4-x-2-cast-iron-rigid-caster-700-lbs-capacity/
and
http://www.steelcasterstore.com/4-x-2-cast-iron-swivel-caster-with-top-lock-brake-700-lbs-capacity/
doing the same for the marver.

and check out how inexpensive (Cheap?) this same companies V Grooved casters are for a rolling yolk at:
http://www.steelcasterstore.com/steel-v-groove-casters-steel-caster-store/
I ordered the $6 dollar version- they have no bearings but made out of steel + I plan to spread load out to 28" (?) wide track so...
Please advise If anyone wants a review after I build
@ $6... worth a shot...
Best-
Andy
and
Thanks.
AB

Rick Kellner
10-09-2011, 12:00 AM
You might consider tracking down what I bought for a glory can. I saw an ad on Craigslist by this guy selling steel tubes 48" long by 30" in diameter, 1/8" thick.

When I went over to check them out, the seller had like a whole back yard full of them. He said that they were the cores that they received rolls of sheet metal on at his workplace. I think they were free for the taking for him, and then he would re-sell them for $30. I was not the first person he had met who had intentions of turning one into a glory.

Can't go wrong with something like this for a small hole and the price is right.

Here is a pic of one I got after I cut it to final length, slapped a bottom on it, and drilled some drainage holes.

http://i1213.photobucket.com/albums/cc476/hyperparasite/021.jpg

Lawrence Duckworth
10-09-2011, 11:35 AM
Wow...that's a sweet deal. Would think some of those guys out west could make use of those big well case drops too.
I know a guy around here that got two 24"drums w/ the butt end discs for 3 private lessons :)

John Gibbons
03-09-2013, 02:43 AM
Hello folks,

I am trying to build a similar glory hole and am wondering how to put the fiber in. Should I get it wet and flatten it and squeeze it between the brick and the steel or should I put it in the barrel first and build the brick up around it?

Also, are there any good threads on recuperating a glory hole. A friend of mine ran the 2 inch metal pipe that went from his blower to his burner over the top of his glory hole just above the doors so that the pipe would get hot and heat the air. This seemed like a good idea but problem I saw with this was that the air only traveled through less that two feet of hot pipe. My Idea is to create a cork screw like pipe above the glory doors so that there is more length for the cold air to travel though the hot pipe.

what do you think?

Is there an optimum temp that the air should be before it mixes with the gas?

Thanks for the help!

John Gibbons

Andrew Brott
03-09-2013, 09:54 AM
John-
I'm not an expert like Dudly Gibberson- so please take my suggestions for what they are worth...
I get all my refractory from Larkin.
http://www.larkinrefractory.com/7113/index.html
They are a smaller company with great technicians- they suggested and we used a batting like frax they sell (can't recall the exact name, call them and ask, but if you do use- please buy it from them).
This pillow stuffing like material was less expensive and worked better than cutting strips or pulling layers + helped prevent SWS (Scratchy Wrist Syndrome)-
You just pull it from the box- wet it (lightly) and ram it with a 2"x4" between the brick arch and and steel to lock all in place.
Our mistake- we over rammed it.
Have built several GHs for others from UWRF on, but this was the first built solely for me, so my assistant Johnny Watson and I put too much effort and pounded the frax layer so dense, I think it acts more like an extra layer of brick, rather than Frax.
Once again, no expert... but bricks hold- frax reflects and it's the air between the layers that counts.
It's that ratio between the 2 that makes these GH's work so well.
Gotta run-
Best form Freret,
Andy
+ be sure to drill a few small drain holes (3/16"?)to let the water out at the bottom of cylinder.
+ to mitigate dust
-USE SWEEPING COMPOUND!!!!- and be sure to run it in your shop vac as well-
- Make sure that has at least a .003 micron Hepa like -
http://www.amazon.com/Ridgid-VF6000-5-Layer-Vacuum-Filter/dp/B0029NY9XU/ref=sr_1_11?s=hi&ie=UTF8&qid=1362843931&sr=1-11&keywords=ridgid+shop+vac+filter
+ and own and use a good respirator like this-
http://www.amazon.com/North-Safety-770030-Medium-Series/dp/B002D95K2O/ref=sr_1_1?ie=UTF8&qid=1362844406&sr=8-1&keywords=North+7700
with a purple cartridge

Randy Kaltenbach
03-09-2013, 10:40 AM
Also, are there any good threads on recuperating a glory hole. The best place to pick up this info will be at the Canadian glass conference in Calgary this coming May where Hugh Jenkins will present a course on how to recuperate. (see sticky thread). If you're looking for top efficiency, he's your man.

Josh Bernbaum
03-09-2013, 02:14 PM
Hello folks,

I am trying to build a similar glory hole and am wondering how to put the fiber in. Should I get it wet and flatten it and squeeze it between the brick and the steel or should I put it in the barrel first and build the brick up around it?

Also, are there any good threads on recuperating a glory hole. A friend of mine ran the 2 inch metal pipe that went from his blower to his burner over the top of his glory hole just above the doors so that the pipe would get hot and heat the air. This seemed like a good idea but problem I saw with this was that the air only traveled through less that two feet of hot pipe. My Idea is to create a cork screw like pipe above the glory doors so that there is more length for the cold air to travel though the hot pipe.

what do you think?

Is there an optimum temp that the air should be before it mixes with the gas?

Thanks for the help!

John Gibbons

You should do what Andrew suggests with the frax, after setting the bricks in first. It's better if you let the mortar set up before you ram the frax in. You can do it a couple courses of brick at a time.

For recuperating anything, I'd think optimum temp is however hot you can get that incoming air. Some systems will perform better than others, but perhaps anything is a step in the right direction. When my GH is hot, the air is entering the burner at close to 1000 F. You need to have a nozzle mix burner for any air coming in that's significantly pre-heated, of course.

Here's a thread:
http://talk.craftweb.com/showthread.php?t=8065&highlight=recuperated+glory+hole

Pete VanderLaan
03-10-2013, 08:15 AM
when Josh says "of course", what he means is that you will have pre ignition in the burner if the air is too hot.

Hugh Jenkins
03-13-2013, 07:22 PM
John, I tried to write a return to your web-mail and it got returned. I did try. You can email me direct and I will answer your general questions. Basically, the hotter the incoming air the less fuel it takes to achieve the same heat. Up to a point of about 500F most premix burners, like Giberson or Wilton or Pine Ridge, will handle that air temp, even though they are not meant for it. But, they may also give problems on turn down to low settings.

If you really want the best from the effort of recuperation, you have to have a different gas/air mixing system. Then you can have air upwards of 1200 to 1500 F and get 60 to 70 % return. There are material application issues and cleaning issues for any recuperation system, but they are way less severe for glory holes than with furnaces, since furnace exhaust carries so much more batch flux and nitrous gases.

The earliest efforts at this for glass shops are covered in the Hot Glass Information Exchange. There were looped pipe, finned radiator sections, double walled furnaces, spiral coiled ceramic stacks, etc. I did my first one with VW cylinders in a stove pipe. All of these proved that up to 30% heat recovery can be done by almost anyone. At that point all the burner design, stack materials, ease or difficulty of construction, things start to show up.

Charlie Correll now makes a really nice studio size recuperated GH, and I think HUB has come up with something too. Wet Dog makes a more brute size and has all the bells and whistles with a super control system. I think I am the only one who does retrofit with shop owners doing most of the installation work. Do not recuperate a decaying GH.

John Gibbons
03-21-2013, 08:05 PM
Thanks Hugh,

I will have to fix that webpage email, but thanks for answering my questions.

John