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TFT

Vertical forge questions

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Im in the process of making a vertical forge ( still have to emply the tank in the proper manner) but i have a few products im thinking of using and was wondering if anyone has used this exact products for advice but...

Ceramic blanket.... claims to be non toxic

http://www.sheffield-pottery.com/SUPERWOOL-607-HT-BLANKET-8-lb-Density-1-p/tcsw607ht.htm

Castable refactory

http://www.sheffield-pottery.com/LOUCAST-3000-CASTABLE-MORTAR-p/lvclc.htm

Im going with the normal layer layout with a bunch of kitty litter as the bottom but whats a good way to make the burner port, forging doors, and lid seal all in one pour/cast. Im kinda weary of the wool and those hazards so i wanna have it kinda sealed off as best as i can.

Im planning on ending up with a 7in dia 8in deep chamber about 308ci( if i did the math right) but im thinking of going with a tee burner(picked up a couple of t fittings today, machine tomorrow). But heres a few picks of my other burner setups in action im thinking theyre good but im just a rookie

First two pics are same burner 

20160831_200219.jpg20160831_200157.jpg

Now other designs

20160819_204916.jpg20160819_203718.jpg

The only reason on my burner questions are i dont think i was reaching welding temp in my old forge(which could be because it was/is terrible and it was only about 110ci) i did it backwards to how most people progress in their forge size. But if you didnt notice im kinda set on NA burners and i didnt even know of frostys tee burner untill today because i thought it was a design that uses the "run" to attach the mixing tube(which im not a fan of their construction) 

Also could i use the different burners for different purposes i.e. welding, ht, temper......

As for the placement and size of the forging ports, should the top of the port be flush with roof of the forge and i was thinking of using 3x4 sq tubing as the mouth/doors 

So thats alot... but any help would be nice because i havent found too many vertical forge plans/ walkthoughs

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First, look around more, before putting up with Sheffield's prices.

Second; if you are confining the fiber blanket between the forge shell and a castable refractory hot-face layer, why do you need to worry about dust exaping into your air space from the blanket?

You need to spends some time reading on some of the casting group sites before trying to construct a vertical forge; the two pieces of equipment have a lot in common. Burners in casting furnaces are placed near the bottom, aimed to create swirl, and also aimed downward in a shallow angle (about five degrees). All these things are done to fight the effects of buoyancy in the burner flame, which otherwise would rob you of most of the flame's heat as it races ineffectually through the forge. This is even a bigger concern for you, since a forge has no crucible placed in it to help confine the flame a bit on its way out of the exhaust opening.

Which brings me to the need to equip your forge with a variable height baffle plate with a small opening for the stock to pass through, rather than a simple lid. Being able to vary the size of the gap between the top of the furnace and the baffle plate allows you to create some back pressure to help balance the effect of buoyancy. The good news is that high alumina round kiln shelves to make baffle plates from are cheap and easy to find.

Finally, I have to aggravate both of us by advising you that, due to the buoyancy effect, a gun burner blasting flame, would probably be a better choice in this case than an NA burner; not that an NA burner won't work fine, but just for the sake of honesty I'm constrained to admit to the best choice:rolleyes:

 

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Thanks for the tips and such

The bouyancy thing i didnt even think about that but you saying something really makes sense... if i get this right i need to keep the flame contained as best as possible without losing heat potential

With the baffle, if i understand, a kiln shelf on a threaded rod hanging from the top would work... but id use it to adjust forge volume... for temp basicly

As for wanting to enclose the blanket is (not sure on this) that the thin hard layer would make it fragile after heat cycling since its a heatsink and i assume the outside would get hot enough to cause damage... and what do you think of the non toxic claim, i was thinking non toxic=non good or non toxic under perfect circumstance

 

And about the burner... i was thinking that id need to go with a blown burner:(

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1 hour ago, TFT said:

With the baffle, if i understand, a kiln shelf on a threaded rod hanging from the top would work... but id use it to adjust forge volume... for temp basicly

As for wanting to enclose the blanket is (not sure on this) that the thin hard layer would make it fragile after heat cycling since its a heatsink and i assume the outside would get hot enough to cause damage... and what do you think of the non toxic claim, i was thinking non toxic=non good or non toxic under perfect circumstance

 

And about the burner... i was thinking that id need to go with a blown burner:(

First, Don't be disappointed about a blown burner, they certainly aren't that hard to construct or use.  I wouldn't write off your NA burner just yet either.  The vertical forges I've seen have the openings at the approximate 2/3 point in the height of the forge.  Really they didn't seem all that different from a horizontal forge, just with a deep well below the opening.  Not 100 sure on the logic behind a preference for a forge like that, though I do remember reading something about it on the Don Fogg site back before I lost the connection there (as an aside, is there still some way of accessing that info, there was some great knifemaking info on the site).

Anyway, I would certainly try your NA burner placed low, like Mikey has suggested, before switching to a blown burner.  With a pass thru door at the 2/3 height, and a lid without a door in it (think in terms of a crown construction for that if possible), I don't see why the door openings would be that different from a conventional horizontal forge.  Admittedly virtually all of the vertical forges I've seen use blown burners, but that doesn't mean you can't be the first to get a NA to work.

Here is a picture of a particularly nice one (not mine): 015.jpg

As regards the variable height baffle plate.  I think that Mikey is considering someone using a casting melter , not a vertical forge, though I may be wrong.  In any case, there is no way that threaded rod will hold up to the temperatures inside a forge (unless you are just using it for heat treating) if it is directly supporting the kiln shelf.  If you have to have a variable height baffle, and I still don't understand the reason for that, I would support it from below with ceramic kiln stands.  These can be stacked to make more or less height and will withstand the temperatures involved.

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Yea im happy i made a few sweet burners so i may have to try my hand with a blown burner... but ill give the NAs a shot

Yea the thread rod idea was just an example for me to understand the concept but your idea is alot more fisable

 

But how good is a kiln shelf as an insulator? Like a high quality one.

But that does look like a high quality vertical... bigger than a propane tank or should i say a bbq grill tank. Which i can get more bbq tanks... or i have a 20gal water heater tank which is huge but can be cut down in height

And for me anyway i like the vertical concept for welding, because flux buildup, i use alot of flux, maybe too much of thats a thing. Another reason being even heating even though i like to use the hot spot.... maybe ill make a 2 burner vert one in the "forging port" as a optional hot spot

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Don Fogg developed his vertical forge to combat unconsumed oxy in the chamber and it's grown to be sort of a "brand" with him. Sort of the same reason I keep building T burners and make my slab hammer handles with a nob on the end.

An old school metal artist lost to us in 2,000 Chris Ray had a vertical forge thingy in a refractory table. Chris sometimes worked to heroic scale. He built his spittoon forge to heat sheet and medium weight plate so he could do repousse and otherwise forge the stuff. The "forge" in the table was spittoon shaped with a round chamber at the bottom then it reduced in diameter and finally flared towards the top. It looked just like a spittoon. I THINK Chris used a spittoon to make his first ones.

Anyway, he could move full sheets around on the table about 1/2" above the spittoon on conveyor rollers. about 1/2" was enough gap it didn't snuff the burner. When he needed a more conventional forge he's dimply use light fire brick to build whatever cover he needed.

IIRC the bulb part of the spittoon was about the size of a basketball. The burner was aligned tangentially to the bulb. One version had multiple burners, one running to anneal, two or three to make serious HOT.

I believe Chris eventually had something like 5-6 spittoons in his sheet forge, or table or whatever he called it. When you work solo you get innovative.

Frosty The Lucky.

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1 hour ago, TFT said:

 

 

But how good is a kiln shelf as an insulator? 

And for me anyway i like the vertical concept for welding, because flux buildup, i use alot of flux, maybe too much of thats a thing. Another reason being even heating even though i like to use the hot spot.... maybe ill make a 2 burner vert one in the "forging port" as a optional hot spot

Kiln shelf is pretty useless as an insulator. I'm also uncertain whether silicon carbide shelves will stand up to Flux. High alumina shelves are the recommendation. In any case if you use that much Flux I would cast a Mizzou inner floor liner and fill it with cheap kitty litter. Then make a second opening, could be the removable top, and clean it out periodically.

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For the bottom being the hard refractory topped with kitty litter would i still need blanket under the refractory... trying to make it as simple as possible.... K.I.S.S.

 

And for the shelves i was thinking kiln shelf forge.... but i figured they were garbage for a insulator but it would be easy

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Unless you plan on spending a fortune in fuel you need insulation in any case. You have a lot of options, all have their benefits and drawbacks.  I'm certainly not going to catalog them all for you.  A kiln shelf forge without additional insulation would be arguably worse than a hard brick forge.  You would be better off with a torch.

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1 hour ago, Latticino said:

Unless you plan on spending a fortune in fuel you need insulation in any case. You have a lot of options, all have their benefits and drawbacks.  I'm certainly not going to catalog them all for you.  A kiln shelf forge without additional insulation would be arguably worse than a hard brick forge.  You would be better off with a torch.

Yea ive never used a kiln shelf for anything and that was just an ideal and didnt give it much thought but i figured id ask about them cause i may have a large suppy for free/cheap... theres a pottery shop near me that noone has tapped

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Though that website maybe pricey do you think those are good products(or ok)... just kinda hung up on the non toxic thing... i didnt shop around yet im just trying to find a good onestop shop

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So how do youll think Bubble Alumina Refractory would work to coat the blanket

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Bubble alumina is expensive per unit volume in my opinion.  As previously stated, many times, there are a number of ways to line a forge, compromises with each.  My current favorite, for a conventional hobby forge, is : 2" 2600 deg blanket, skim coat of rigidizer, 1/2"  - 3/4" of high alumina refractory insulation (kastolite 3000 or equal), loose casting of high alumina refractory (or Mizzou) in the major flux areas and for flame impingement (or split high alumina brick or high alumina kiln shelf.  The bubble alumina can be used for the last coating indicated.  Then if desired a final coating of some kind of IR reflecting material (not completely sure of the utility of the IR material, but folks I respect swear by it).

14 hours ago, TFT said:

Though that website maybe pricey do you think those are good products(or ok)... just kinda hung up on the non toxic thing... i didnt shop around yet im just trying to find a good onestop shop

As regards the non-toxic thing; must be a matter of fine definition. I certainly would wear a respirator and gloves when installing and up till full rigidizer coating.  I have lung damage from not taking these precautions with high temperature blanket and urge everyone else to avoid this at all costs.

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Uh, Kast-O-Lite 30 is a 3,000f. high alumina BUBBLE refractory and in Anchorage less $ than Kast-O-Lite 3000.

The breathing hazard ceramic blanket represents is a long term high exposure issue rather than toxic. It's not any more toxic than a knife blade is. Shouldn't breath it though, especially after being exposed to vitrifying temperatures.

Frosty The Lucky.

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Yea the price thing is kinda not a problem if its worth it 

Im just trying to pick though all those options but dont know whats best... and for my purpose im thinking the standard 2" of the inswool/kaowool, just laying that out inside the sides of the tank(bottom still steel), cutout the ports, rigidize(cure), spread some xxxxxx refractory all over everything covering all the wool and bottom(cure),then itc100(cure), does that seam like it would hold together? 

6 minutes ago, Frosty said:

Uh, Kast-O-Lite 30 is a 3,000f. high alumina BUBBLE refractory and in Anchorage less $ than Kast-O-Lite 3000.

The breathing hazard ceramic blanket represents is a long term high exposure issue rather than toxic. It's not any more toxic than a knife blade is. Shouldn't breath it though, especially after being exposed to vitrifying temperatures.

Frosty The Lucky.

Very good point and i see the kastolite comes with good regards

Almost forgot for the lid i was thinking insboard with a coat of refractory and itc100

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Screenshot_2016-09-09-20-49-22.png

Sorry for the screenshot but does that seem like what a non-rookie would get?

Could i be missing something?

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So does anyone have any tips on removing the valve on a bbq propane tank? 

If i cant get that off ill have to move to the 20gal water heater tank and just cut it down to the right height

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WOW, those prices seem high and I live where shipping about doubles everything! We must be really lucky to have the distributor we have close. I lot may be the brands too.

It looks like a pretty complete list. I see: the insulating blanket, backer, the rigidizer, board for the floor. castable hard refractory Kast-O-Lite 30 LI and ITC-100 kiln wash.

You lost me on removing the valve on the BBQ tank.

Frosty The Lucky.

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I clamped the empty bottle under the weight of a 15 ton crawler loader bucket and used a 4 ft cheater on the wrench and it came right out. .

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Thanks frosty... but the board was for my lid and where do you buy from... for possible future uses

And me and my buddy got it off with the aid of a ratchet strap a piece of rebar a bunch of firewood and a ~4ft pipe... Straped tank to the (uncut)firewood used the rebar though the handle of the tank resting on the wood then i went to work with the pipe while stepping on the tank to prevent the tank form turning... and my buddy was also preventing the turning of the tank.

Even after filling it with water, twice, and using a propane torch on a ~20ft poll "light" any left over gas(nothing happened) it still stank up my garage. So its outside 

And im think im gonna need another tank or this forge is gonna be too small but the water heater tank is still "on deck" 

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The odorizing agent is "mercaptain oil" if you mix a cup or two of laundry chlorine in the water filled tank and let it soak it'll deodorize it. The stuff is very sticky and is probably the #1 thing Mike talks about plugging burner jets.

I buy refractory from EJ Bartell in Anchorage and the Alaska club enjoys a commercial discount. They're also a HVAC service company and it's not legal to use ceramic blanket refractories servicing boilers, furnaces, etc. unless it is cut from the roll. This means there are dumpsters of rems in the yard, when the dumpster is full it goes to the dump. I haven't paid for Kaowool in years. They are who I buy Kast-O-Lite 30 LI for the club price of $78/ 50lb. bag. Retain is $99/50lb bag. Retail ain't a bad price either.

There aren't any local sources for kiln  shelf, refractory board, etc. Bartell will order it for us but we might as well order online ourselves.

ITC-100 priced itself out of my market, last time I checked it was $136./1lb. pint can, WET. plus around $25 shipping. Instead, a few of us in the club got together and purchased a max load for an USPS flat rate box of "Zircopax," Zirconium silicate, flour from Seattle Pottery. The final cost delivered in the mail was $3.76/lb total,  The Seattle Pottery people really treated us well, they went out of their way to ship it USPS flat rate and that took a little extra handling on their part. I've done nothing but sing their praises since. They're just as agreeable on most issues. Great prices and helpful folk.

Zircopax is just zirconium silicate flour without a binder, unlike commercial kiln washes like: ITC-100, Plistex, Metricote, etc. I've been experimenting with mixing it with the Kast-O-Lite 30 high alumina water set castable refractory. Boy was that a mouthfull but that's what I'm experimenting with.

I've been working on designing a new forge, my last portable isn't cutting it. If it works I'll post some pics and dimensions with reasons I'm doing it that way. However, I'll probably try other forges down the road, I've only been using propane for maybe 25 years I have a LOT to learn.

Frosty The Lucky.

 

 

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Yea it seems like you got the hook up... i asked my buddy hows in hvac if he uses the stuff and he said no but i dont think hes rebuilding boilers or anything

But thanks for the tip on the smell ill try that out tomorrow cause i rigged up one of my crappy forges and did some work so im tired

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Thanks TFT for the link to superwool I'll have to see if they ship to the UK. I would much rather use a non toxic insulation than the stuff I've got. 

Thanks Gary

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Hey man i have no faith that itll stay nontoxic after heat cycles... and ive been told those prices are high 

 

Update.... materials should be here friday and tonight im going to get a 100# propane tank for the shell( not going to use all of the height tho)

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Unless you know that you are going to need that kind of size I would highly recommend staying smaller to start out with.  Many of us went way larger than needed with our first build(s) and that costs more money in building materials AND fuel use later on.  I mainly forge blades, but my current propane forge shell is a disposable helium tank for blowing up party balloons.  It has the same dimensions as a freon/R134 tank and I'm actually considering going even smaller than that.  As long as you put a pass-through at the rear of your forge you can work on just about any straight stock that will fit through your openings.  Since you can only work about 6 inches of hot steel at a time before it cools to the point where it needs to go back into the fire there is no real advantage to being able to heat longer sections for general forging.  If you are doing long twists, oddball shapes, or other very specific things then you may need more length, a bigger chamber, and/or multiple options for getting the steel where you want it to be heated, but if this is just for getting your feet wet you'd be much better off resisting the urge to go big.

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