Got my Devil Forge 2 burner in 20 days early

[louspinuso]

So as I mentioned in my introduction, I purchased a Devil Forge DFSW2 forge.  I've seen mixed reviews about them online, however, I've also had the opportunity to use one that I borrowed and it seems to work really well (to a newb like me).  This, along with the fear of building a burner poorly, led me to find one on Ebay for $179 shipped. 

A lot of what people were complaining about in the older versions of this forge was that the regulator is for European propane tanks and that the wool needs to be encapsulated.  Well, the forge now comes with the EU -> US propane adapter and 250 grams of rigidizer that you have to mix (10:7) with water and paint on to the ceramic wool.  The only thing I'm not clear on is if it's still required to have yet another coating over the rigidizer (I've heard mixed answers).

Anyway, I figured I'd do an unboxing video of the forge to show what comes in the box and how it's packaged.  I'll probably do a video when I have some time (probably this weekend) to paint on the rigidizer.  Sorry for the quality, my camcorder was set to the wrong setting.

 

Let me know what you think.

[Mikey98118]

The two burner model for $179 is a pretty good price!

Yes, you will want to do a seal coat in the forge. The rigidizer helps protect the ceramic fiber blanket; toughen it up; but, without a seal coat, nothing protects your lungs from the fiber.

Also, the right seal coat will make the forge run hotter, with less fuel burned.

[louspinuso]

Thank you Mikey. 

When you say a seal coat, do you mean something like this?  This is something that I can pickup locally and the description says, under "Used as surface coatings" section, "Greenpatch can be diluted with water and "painted" on, or applied in layers from 1/8" to 2" thick. Thermal dryout may begin immediately. A maximum heatup rate of 100°F (55°C) per hour is preferred."

Not sure how I'd accurately heat it at 100F/hour, maybe stick the whole thing in my oven?  I think the lowest my oven gets, however, is 175F.  Thoughts?

[Mikey98118]

That should work okay. There are better choices, but not at that price. Before you use a seal coat you want to "butter" the rgidized surface of the insulation; that is, you want to wet it for good adherence. This means that, even though you have already fired the the forge and brought it fully up to heat to set the rigidizer, there will be plenty of moisture trapped between the seal coat and forge shell. This is not good. Drill a small (3/16") hole in the middle of the bottom of the forge shell, so that the live steam and water can run out of the forge, when you fire it up to heat cure the dried seal coating. 

[louspinuso]

Excellent, I'll keep this in mind.  I'll be working on this over the weekend.  If the temperature holds out overnight (Florida weather can be so nice in February), I'll put the rigidizer on in my garage later and then let it dry overnight.  I'll fire it up on Saturday morning to make sure it's hardened and then Saturday night I'll "butter" and apply the greenpatch (and then start the thermal dryout in the oven).  I'll probably film *most* of this and put out another video including your suggestion to drill out a small hole.

Once again, thank you.

[Mikey98118]

And thank you right back. This kind of information is what lots of people need. I have been making burners and forges for twenty years, and some of those new imports give me the itch to buy one of them too! Lots of newbies out there are going to watch your posts closely.

[MaxwellB]

louspinuso

I commented on your post on the "other" social media aggregate site. Glad to see you found your way here. I'm not sure if you saw any of the other posts about the devil forge, but the bits of kaowool they give you to plug the gap between burner and forge housing work best when torn in half thickness and then into pieces. Don't try to cram the whole lot in there, won't work.

I've got the same brand forge, but square and with the back door flap. Can't wait to get the chance to put it through a session instead of using it as a space heater for when I'm working on my anvil stand and prepping my work area. 

[louspinuso]

MaxwellB, thanks for the info. I was wondering about that and whether those gaps actually needed to be sealed with the wool. My thoughts were more along the line of, if I do put that wool in those gaps, do I need to rigidize that also? And if I rigidize it, do I also need to seal it with refractory?  

I was going to rigidize last night, but my brother and his wife came by and we were hanging out till about midnight at which time I didn't want to narrate what I was doing while possibly slurring (I shounded totatatally fiiiiine to myshelf).  Hoping that tonight I'll be able to put the rugrat to bed early and work on it, but I doubt it as my wife has made plans for dinner at my brother's house.... So Sunday? At least I'm not working on Monday due to presidents day so I should be able to get some stuff done by then.

Hopefully. Lol

[MaxwellB]

As the wool isn't in direct contact with a forceful flame I would say that rigidizer should be sufficient protection. I didn't paint any of the included stuff on mine, as it's just at the very opening at the top and more of a protection against heat loss.

I bought some kiln wash I might slap on there tonight and fire it tomorrow to cure/set. If not tonight than the next few days. Then I'll consider the forge prep finished since I got firebrick too to use as a stand instead of the retaining wall blocks that hold moisture and aren't going to be happy about being exposed to heat.

Soon!!

[Frosty]

On 2/15/2019 at 11:09 AM, louspinuso said:

I'll probably film *most* of this and put out another video

Please no videos, most of the members here don't have broadband connections and have to pay for bandwidth. Stills are better information as we can zoom in on details and they don't jitter around and play annoying music.

Frosty The Lucky.

[Eventlessbox]

Thank you for posting about these forges. Seems like people feel a stigma about talking about them if they didnt build it themself. 

How large are the burner ports on the forge? In case I decide to replace burners with some frosty-T later.

Also how is the red rubber hose they provide attached. The seller I found offers a $20 discount if you don't get the regulator kit from them so I thought I might use my own.

Finally a question for our gas gurus. From what I read about specs they come with 1" ceramic wool insulation. Properly sealed with castable and a final coat of reflective, is this enough insulation. 

Really appreciate the info as this was a route I am seriously considering to replace my ugly metal box when the bricks start to wear out.

[Mikey98118]

5 hours ago, MaxwellB said:

As the wool isn't in direct contact with a forceful flame I would say that rigidizer should be sufficient protection.

Okay, now we are getting into safety territory. On the one hand its even more important that the fiber will be located outside of the interior, so not only will it not contact flame, but it should never reach anywhere near the 1600 F where cristabolite is formed. Soooo, rigidizing should be sufficient. On the other hand flat washers on the mixing tubes will be sufficient. Just a thought.

[louspinuso]

Frosty, how about I film it and post it to YouTube so that people interested in watching it happen can.  And I'll also take pictures from time to time through the process and post those directly to the thread?  The YouTube link shouldn't waste much in the way of bandwidth as the browser should not load the video from another site, though the forum software may load the preview image for the video.

Eventlessbox, I'll take measurements with my calipers and post them.  I'll give you the various ID's and OD's for the everything I can get at.

Mikey, If I understand you correctly, you're saying I could use flat washers instead of stuffing that wool in place.  Would the washer need to be welded down? or can I just place it there so it basically covers everything, but isn't actually fastened?  I'll take pictures tomorrow to clarify.

 

Thanks all for the feedback!

[Frosty]

1 hour ago, louspinuso said:

Frosty, how about I film it and post it to YouTube so that people interested in watching it happen can.  And I'll also take pictures from time to time through the process and post those directly to the thread?  The YouTube link shouldn't waste much in the way of bandwidth as the browser should not load the video from another site, though the forum software may load the preview image for the video.

That would be perfect Lou, thank you. So long as they're not links to commercial sites Admin has no heartburn with links. I believe IFI has a section listing good video how to links. You'll be golden.

I'd certainly put a layer of hard refractory on the inside of the blanket. It not only protects the kaowool. from temperatures above it's rating but more importantly mechanical damage. Kaowool at forging temperature is only slightly stronger than cotton candy almost any touch tears, gouges, etc. Ceramic blankets are also extremely susceptible to forge welding fluxes, it's like pouring hot water on cotton candy, dissolves it almost instantly.

Frosty The Lucky.

[Mikey98118]

On ‎2‎/‎15‎/‎2019 at 12:41 PM, louspinuso said:

Greenpatch can be diluted with water and "painted" on, or applied in layers from 1/8" to 2" thick. Thermal dryout may begin immediately. A maximum heatup rate of 100°F (55°C) per hour is preferred."

I would simply use the standard drying cycle for another refractory used here (Kast-O-lite 30), by slowly drying for a week with a damp towel over the exhast opening with the forge within it, to slow drying time, and then using an incandescent light to provide the heat, (but keep it much lower than any oven can) for a day; then transfer the forge to a kitchen oven to continue drying out all chemically locked water, and then finally fire the forge using its burner.

[louspinuso]

Mikey, since I have a forge that is open on both ends, I should probably cover the ends with a damp towel also.  Or do you recommend something sturdier?

I just rigidized and took a tone of pictures and video.  I'm just going to go through the process of cleaning up the pictures and video so that they actual give actual information (instead of just distracting background noise).  I'll probably be posting those tonight as I need to get ready to go to a kids b-day party this afternoon.  Tomorrow afternoon I'll also post an update on how dry the rigidizer is (I've read it should only take 24 hours to dry and the humidity is pretty low for FL right now, only 55%, lol), I suspect it will be Tuesday night before everything is dry enough to put the refractory lining on.

Frosty, thanks for the encouragement and information.  I certainly wouldn't want to damage the wool/liner and breathe in any of that nastiness.  Another thing I'm going to do, though I'll keep that separate and possibly not even post a thread here at all unless people are interested, is rigidize my cousins wool in his devil forge.  He purchased his before they sent rigidizer and I've been told by the ceramics place I picked up the "Greenpatch 421" that it can be used, when watered down, to rigidize wool, and then, once dry, apply as a refractory lining.  Since his wool is a little beat up, I'm not sure how well it will work, so if it's really horrible, I'm just going to order him some new Kaowool and do it from scratch.

One final question, in general how hot will the outside of the forge get, specifically the metal housing?  I'm only asking because I think I'd like to paint the outside with some high heat paint, if possible, so it's not just a boring flat black.  Obviously that's not necessary, but I think it would be nice to give it a little bit of flare.

Thanks again everybody.

[Frosty]

Lou: I didn't mean to make the music and jittery video thing personal, it's just a thing for me.

Greenpatch, Kastolite and most other high temperature refractories do NOT dry. They set like Portland cement bonded materials like hydraulic concrete. Calcite based cements hydrate, absorb water and form strong hard to break bonds on a molecular level. If I'm wrong I look forward to the correction.

Clay refractories like fire clay, bentonite, kaolin, etc, dry and or vitrify at a high temperature or cinter at high temp and enough pressure, they're two entirely different processes. 

I sure wish the  refractory manufacturers would put basic instructions and mixing ratios somewhere easy to find, like the . . . label on the package!

The stuff cures just like concrete. It takes time and hard kneading to mix properly, you have a working time that depends on how much water you've included and how much you work it. Like concrete if you keep mixing it it doesn't set. When it sets it wants 100% humidity to cure to max strength, exactly like concrete. I just put my forge in a plastic trash bag with a couple three cups of water and close the bag with a twist tie. Over night has worked nicely for me but longer won't hurt and recommended from the makers is 7 (SEVEN) days. A wet towel would be perfect, damp not so much. It REALLY want's 100% humidity, once set you could probably put it in the swimming pool. 

We don't need our forge refractories to be anywhere near as strong as a factory furnace. I've found it's plenty strong with an overnight cure cycle, then a firing cycle to dry the Kaowool, a little red for a while and it's ready for duty.  The makers of these products make them to hot patch furnace liners according to the literature. Seriously, send guys in aluminized fire suits with trowels or gunnite it, on flipping RED hot furnace walls! They recommend applying thin coats when HOT patching to prevent excessive flaking. Letting a furnace cool is of course better but they don't turn these furnaces off but a couple times a year to reline completely and overhaul the works.

Greenpatch does work as a rigidizer when mixed skim milk thin, I've tried it and it works pretty well. I don't talk about it because I can buy a 1 lb. can of fumed silica, for $8 and tax here. I've also experimented with Kastolite as a stabilizer. Sift out the aggregate makes it a lot easier.

My current ribbon burner forge is kiln washed with zircopax and sifted kastolite. I'm not really recommending it as a kiln wash I think there are better home brews but its working fine.

We're expecting you to let us know how hot the outside of your forge gets. I've never seen one in person let alone used one. 

Frosty The Lucky.

[Mikey98118]

2 hours ago, Frosty said:

Greenpatch, Kastolite and most other high temperature refractories do NOT dry. They set like Portland cement bonded materials like hydraulic concrete. Calcite based cements hydrate, absorb water and form strong hard to break bonds on a molecular level. If I'm wrong I look forward to the correction.

You're not wrong, but you're also not right.

Refractory cements, inlike Portland cement, can dry completely. because it is possible to completely drive out their chemically locked water content. You are right because most people never do dry out their cast refractory products completely, which for Kast-O-lite products require getting them yellow hot all the way through; otherwise a discernible line between the inner portion of the refractory and where the outer portion remains. I first noticed this back when I was making casting furnaces with 2" thick solid cast refractory walls. If the refractory is raised to yellow heat all the way through, then it vitrifies all the way through, just like ceramic plates and mugs do

[Frosty]

Have you found their literature? I may have missed something but for max strength the calcite bonded refractories like Kastolite and Greenpatch need to be kept at 100% humidity and not allowed to dry before its completely cured.

The yellow heat cure is NOT a drying process, it's more like vitrification but not quite really either. I didn't understand what they were talking about, too much high temperature chemistry, with: charts, graphs, times, lists of variables and how everythinng effects everything else. The process and lay descriptions seemed pretty plain. 

I'll have to see if I can find the site that discusses the hows and whys of the stuff. I chased it down when I tried Kastolite and it was making orange dragon's breath. Then the sheets for Greencast which read pretty much the same. It was a serious PITA locating it, they kept wanted to connect me to sales. I tried again later but gave up.

Frosty The Lucky.

[Mikey98118]

Well, let me lay one last complication on you. Even when perfectly fired all of those refractories can regain some water content from humidity, unless they are completely finished with a vitreous finish coat How much water gain depends on how much percentage of silicate they contain; that isn't very much in high temperature refractories, because silica lowers their rated temperature maximums, and increases thermal transfer; both very undesirable outcomes.

[louspinuso]

Frosty, no offense taken.  I've got thicker skin than that.  Living in an area where broadband is so prevalent and easy to get makes me forget that there are still people out there on <1Mbs so I appreciate the reminder.  As for shaky cam/music thing, I agree 100% with the shaky cam which is why I generally video things from a mount in one angle.  If I have to move the whole camera, that move gets cut out.  I remember when Blair Witch was all the rage and I just couldn't watch it without getting motion sick because of it.  Now it seems every horror movie is filmed like that, I get it.  As for the music thing, it's a mixed bag for me.  If I'm watching a video that has a fast forwarded section that has no narration or talking during it, I like music that is quiet just playing in the background, but if the person/people are speaking, no music at all.  It just detracts from trying to understand what is going on.

I do understand that concrete cures as opposed to drying, but this is my first foray in refractories and it seems that many of them use vastly different instructions for how to prepare them (from letting them dry and firing to allowing to cure).  I am very seriously trying to find the literature for this product but all I've found so far is the SDS  and a PDS.  The SDS, from their website, only has this section on "handling"

7. Handling and storage Obtain special instructions before use. Do not handle until all safety precautions have been read and understood. Keep formation of airborne dusts to a minimum. Provide appropriate exhaust ventilation at places where dust is formed. Do not breathe dust. Do not breathe dust. Avoid prolonged exposure. When using, do not eat, drink or smoke. Should be handled in closed systems, if possible. Wear appropriate personal protective equipment. Wash hands thoroughly after handling. Observe good industrial hygiene practices.

Which offers little to no information.  The PDS, does offer a bit more information (though maybe not as clear as I would like):

Description: 3200°F, Wet, Air-Setting, Thick Patching Mortar Features:

• Can be used as patching material, a coating, and for bonding brick such as EMPIRE® S, CLIPPER DP®, KX-99®, KX-99®-BF, and KRUZITE®-70.  
• Supplied as a thick patching mortar; can be field-adjusted with water as needed.
• Can be fired-in faster than regular high-alumina mortars. Uses:
• Boilers, brick plants, steel mills, asphalt plants, and iron foundries.
• Protective coating over ceramic fiber modules.

And then later this:

Mixing and Using Information Per 55 lb Pail

• Material is supplied ready to use and can be field-adjusted as required.
• Water Required—Thin Trowel Gallons Liters 0.125 0.45
• Water Required—Dipping Gallons Liters 0.625 2.3
• For detailed mixing and using instructions, contact your HWI representative or visit www.thinkHWI.com.

Heatup/Dryout Schedule

• Not applicable

Installation Guidelines

• See HWI Installation Guidelines M-1—Wet Mortars—Ready to Use.

And while typing this I thought maybe just google for the document name (HWI Installation Guidelines M-1—Wet Mortars—Ready to Use) and I found this PDF which seems to have a bit more data in it on how to prepare/use the product, namely:

• Use Drinking water between 60 and 80 degrees F if required.
• There is no cure or set time needed for this product
• A weep hole should be used (guess I'll be drilling one before applying) to allow moisture to escape to prevent spalling or probably lining damage
• dryout and heatup are governed by brick requirements, typically 100F per hour (indicating that maybe once it's cured it doesn't require heatup)

So based on this, I think my next steps are:

1. Wait for rigidizer to dry completely
2. Drill a couple of weep holes in the bottom of the forge body
3. Apply Greenpatch to the lining in the forge
4. Cover all the ports with wet towels
5. Wait for the Greenpatch to cure (even though the directions specify that there is no cure or set time needed) I'd rather let it go slow to avoid rapid shrinkage and cracking
6. install burners and fire

Looks like I've got some work ahead of me for the next couple of weeks.

 

[louspinuso]

Ok, so after a long day out at a kids birthday party and visiting with a relative that is down from NY, I was finally able to get home and... wait for the baby to fall asleep (my office is right next to his and if he hears me in here before he passes out, he doesn't).  Anyway, now that he's sleeping (and I've replied with what I've found about the Greenpatch 421), I figured I'd post the photos I took today.  I still haven't finished processing the video so that's not ready.  I need to re-narrate it as talking with a respirator on is not recommended.

Anyway, let's get started.  I've resized the images here to prevent it from being bandwidth heavy.  Please let me know if they are still too large.  I started by measuring the rigidizer that was sent to me to confirm it is, indeed, 250 gr.  once I did that I decided that I'd mix it at the recommended ratio in small batches of 100gr rigidizer to 70gr w ater.  I placed 100gr rigidizer in one container (measured on a scale) and 70gr water in a second container.  Once I had the right amounts I poured the water into the powder and mixed.  I didn't capture an image of this, however, I stirred for about 7 minutes and the consistency was about that of medium thick gravy.

 

I then painted the inside of the forge, top and bottom, in one half (front? is there a front?)in a nice thick layer.  I then applied rigidizer on the edges of the wool in the burner port.  This pretty much used up the mixture so I measured out another 100gr/70gr mixture and mixed same as before.  This time I turned the forge around and did the other half and the other burner port the same exact way.  Any remaining mixture I went through and found places where air pockets had formed and were showing dry wool  I applied to those and made sure everything was looking good.  This was about 12:45pm this afternoon.  

 

At 8:41pm, this evening, you could already see the edges drying up. 

 

You could also see the mess I left on the outside of the forge body and the burner ports. 

 

 

Luckily, this stuff cleans up with water so I took a wet rag and wiped everything on the outside gently and washed away the rigidizer, leaving a clean looking body.

 

That's it for now, about as far as I'm able to get tonight.  I'll take progress pictures of the drying/curing process tomorrow morning and again tomorrow afternoon in the hopes that you can see how it's holding up.  

 

[Mikey98118]

2 hours ago, louspinuso said:

Wait for rigidizer to dry completely

NO!!!

(1) Use your burner to force dry the ceramic fiber insulation, or let it dry naturally; your choice.

(2) Fire the ceramic fiber insulation in the forge to insure that its fibers lock in place.

(3) Then continue with your list...

[Frosty]

Now I'm wading through sites and remembering what it was like last time. However I did find a little useful information including mixing instructions for Kastolite 30 li. Seems someone on the forum found a site with good information and posted it here. It's a few posts down the page. 

Guess who?

https://www.iforgeiron.com/topic/47453-how-to-kast-o-lite-30-and-kaowool-scraps/

 

I'll see if I can track some info for the Greencast. Weird I was searching for it and came across the Kastolite links including the one to IFI. Maybe I should search Kastolite and learn about Greencast?

This is really bringing back old memories and headaches.

Frosty The Lucky.

 

19 minutes ago, Mikey98118 said:

NO!!!

(1) Use your burner to force dry the ceramic fiber insulation, or let it dry naturally; your choice.

(2) Fire the ceramic fiber insulation in the forge to insure that its fibers lock in place.

(3) Then continue with your list...

Are you sure Mike? This isn't fumed silica, it looks like a thin water set refractory. I've never seen the stuff.

Frosty The Lucky.

[Mikey98118]

I'm speaking about silica based rigidizer; there are one or two alumina  based rigidizers; is that what you have?

Okay, I want back and read the caption on the two photos; I had assumed it was the Green patch you were showing. If it is what they sent as rgidizer, it is completely unfamiliar. It looks like some kind of refractory. Did it seem to soak into the fiber much?