Insulation and Refractories

Sealing and high-missive coatings for ceramic fibers and other refractory surfaces Even rigidized ceramic fiber products still need to be sealed for safety. Furthermore, the various coatings used for sealing tend to create a tough surface layer that holds high-emissive coatings from peeling away from the fiber’s surface; an irritating tendency that results from spreading high-emissive coatings directly on fiber products (especially those that aren’t rigidized first). Just as not all sealants are rated as high-emissive, not all high-emissive coatings are effective sealants, so you need to review the better-known products. There are also products, such as shell coatin…

1) The shell is the container that holds the blanket, etc that makes the forge. The propane tank will be the shell. Yes? Next comes 2 layers of 1" 8lb. Ceramic wool refractory such as Inswool insulating blanket. Kaowool is another product but is becoming a term for the wool refractory. It's a high temperature insulating layer made from ceramic fibers. Next the rigidizer both stiffens the ceramic wool refractory and contains the fibers so they don't break free and drift in your air. The stuff is a breathing hazard and can do permanent lung damage. Ceramic Wool Insulation, Safety Alert The hard refractory comes next and provide armor against both heat, flam…

This post has been edited. The thread went off subject and is too important to not bring to the attention of the community. ---------------------- Chuck Wright Tuesday at 05:24 AM You need to rigidize and coat your ceramic wool insulation to keep from having the fibers from blowing in the air and landing in the lungs of you and your family. That can result in severe granulomas of the lungs and eventual silicosis and cancer of the lungs in any age group with the risk climbing with each exposure. Below is a pair of xrays of a 28 y.o. man with 7 yr history of blacksmithing. The X-ray on the left was when he was 21 and the one of the right is the X-r…

Please forgive my ignorance and the long description. I’m brand new to this forum, to smithing, and to all things dealing with a forge. I bought a Vevor 3-burner propane forge for my 13 year old son as a Christmas present this year. He expressed an interest in forging and I was all for anything that would help transition his heart from playing computer games to getting outside and using his hands to create. Also, thought it would be a great way for us to spend time together. The forge came with a bag of refractory cement. After reading the instruction manual several times, I began assembling the forge. The instructions didn’t mention what to do with the cement as …

I have some INS-TUFF ceramic fiber rigidizer. The instructions do not specify to dilute but the two online kits I've gotten in the past that came with an unbranded rigidizer instructed to dilute 50/50 with water. Does anyone know if diluting affects the hardening?

When pouring concrete we put rebar in for strength, to help prevent cracking, to tie together old and new.... Does anyone use chicken wire when putting refractory cement in their forge? Is it a dumb idea? I'm not sure how it would react internally to all the heat cycles. Thanks, Dark Horse

I was wondering if abrasive coal slag can be used as an ingredient in any refractory product. What else (other than an abrasive) could it be used for surrounding foundry work?

So, most of you have heard of Aircrete. The mixing of cement with foam to produce a lighter yet strong version of material. I've researched this and found the right mix and ingredients for small batches. 5gal Bucket of Aircrete = 4.7lbs cement 2.5lbs H2O or 32.8oz 2.1gal foam (Made with Drexel foaming agent) Has anyone ever tried to use refractory cement with a foaming agent? I use HPV®-ESX CASTABLE, from HWI, (A fused silica castable designed for thermal shock resistance) for building my ribbon burners. Its pretty pricey (well at least to me), but i've only used it to make the burners, not as a forge lining. Any thoughts or ideas on thi…

I have a Nargesa H2 two burner gas forge and the compacted vermiculite insulation is crumbling apart. Not so bad on the sides exposed to heat but the backside and other non heat exposed pieces just keep shedding crumbs and disintegrating. I'm thinking humidity breaks this stuff down but the manufacturer of this forge says I'm the only one with this problem which I find hard to believe. https://photos.app.goo.gl/fjR6EwGEhNaoqi4X8

Mods, please remove this if it's against rules but I feel that this is very critical information for the blacksmith community and will be of great benefit. [Mod Note: the following has had the commercial links removed, but the information within the post has been left intact. Those seeking information from the manufacturer's website can look it up on their own.] I'll keep this post as condensed as I can to get right to the meat. Ever since reading this post ( Ceramic Wool Insulation, Safety Alert), I have been actively looking for new ways on how to avoid the 2 main problems with ceramic blankets: The Biopersistence problem - In short: When handling the bla…

I have about 100' of 1" blanket that i have had for a while now in my barn. The wife was moving somethings around and she put it in a spot that got rained on the other day. So my question, does getting wet hurt it? I moved it and t has pretty much dried and has not mildewed or anything just got a bit wet for a couple days. I got this a couple years ago to build a foundry furnace out of, but never got around to it so i was going to donate it at the next hammer in i go to in April.

Hi, new here, need some help pls.. Bought my son a used devil gas forge as he has been enjoying the charcoal forge but its a lot of smoke not very User friendly. The devil forge seems great, previous owner painted the insulation the powder it came with but the coating is very fine and inconsistent. I would like to re-coat it with a better layer of refractory but struggling to find anything in the UK. I've seen Mr. Volcano satanite on amazon that'll ship to the UK, will that do the trick? Will 2kg do 2 coats on a double burner forge? Any alternatives appreciated. Thanks Chris

Hi there folks, is there a product that acts both as a rigidizer and adds some small amount of protection to ceramic blanket? I am just finishing up a prototype forge for the Farrier industry. As these forges are portable, the ceramic board insulation takes a beating as we drive down the roads, especially if the forge is in a trailer. Some have found their forge liners breaking down in less than 6 months. There is a need for another solution. I have designed a forge that will use only blanket insulation for the walls and roof (sort of a mailbox design). We will see if they can take the banging down the road any better. I have read until my head is swimming about…

I am building a propane tank forge, and found a local supplier that has ceramic blanket for a really good price. Problem is, is that it is only rated for 2200 continuous use, 2300 max. Is that going to be high enough? I do plan on covering in Sodium silicate, then Kast-O-Lite. Thanks.

Does plistex glow hot orange for a second when it is cooked in.i think i remember metrakote having to turn bright orange yellow to completely cure. Thanks all and take care too. It over kol. Can I burn this plistexn on my propane burners or do i need to wait til tomorrow for my 2 firebricks?

So, I'm trying to find a recipe to make some homemade refractory cement to replace my old refractory plaster stuff, and I've found a few, all of which involve Portland Cement as their base. But I've also found a few places that unequivocally say not to use Portland Cement, because it will spald. But none of these explain if this is universally true, of if it's only true of straight portland cement. So, I was hoping I might be able to find some people who use a similar recipe to what I've found, who can tell me how hot you can get it before you run in to issues. Mostly I just want to cast aluminum and forge iron, but my roommate and I had been talking about trying to…

Just starting out, going to build my own forge and was curious if a 3M welding blanket would be a sufficient substitute for the fireproof fiber blanket required inside the forge?

Hi All I've been playing around with the odd bit of forging on and off for the last 10 years, I've built a few simple coke and charcoal forges mainly from advice I've found on this forum. I've been looking into what seems a minefield of purchasing a gas forge, I've seen a few online available in the UK. I Understand that the ceramic insulating wool should be protected with a ridgizer, then a refactoring coating, then optionally a IR reflective paint? Is just the suitability of the products available in the UK I'm struggling with? Most the forges kits I've the option to buy don't include refractory, and none have a ridgizer? Two produ…

Howdy,

I've been reading about used oil burners for casting and trying to come up with a recipe for some homemade refractory for the burner. I have portland cement and perlite kicking around the farm and some hard firebrick. I was wondering if, while it will be a fair bit of work, crushing up the firebrick would work for the refractory or will I still need new fireclay or benntonite clay?

Hello all! I've been reading some of the awesome posts on this board and wanted to check a few things before I go too far. First off, my wife bought me a 4 burner propane forge from amazon called the Atkrou. Links are not allowed in the forum I believe so posting some pics of the forge, the container for quench and some tools. I then bought the cart with wheels and some firebricks to set it on. So a few things I'm planning to do I was hoping to get your opinions on: 1) I ordered 16 ounces of Mr Volcano Rigidizer concentrate (makes 32 oz), 5 pounds of Kast-O-Lite 30, and 2 pounds of Plistix 900. The manufacture instructions says you don't need any kind of r…

I recently got a great deal on a bundle of these IFBs (38 of them for $40). They are not like the lightweight white IFBs I am used to. They are much more like regular hard (non-insulating) fire bricks, but they are clearly marked IFB. They measure 2.5”x4.5”x9 and I did not weigh them, but they weigh about as much as a brick should - not lightweight like the white ones. Can someone help me identify what type of brick (high alumina?) and maybe a max temp associated with the type? TIA Bonus question: there are two in the bunch that are slightly smaller and are marked EJB. Identification on those?

Is there set plans to put bricks in a propane tank so I can skip kaowool? I know you can make one out of angle iron and bricks but like the durability of it closed in a shell. The "bottom" of the tanke has been smashed flat to an 8," bottom. I will use a venturi and am tired of replacing lining after every two forgings because the heavy weight makes my cable bend, making it scrape top or bottom everytime. In two years I've kastolited, kaowooled and buttered about 9 times. I need no info on kaowool, I will not use it. I'd hoped to soft brick. Then hard brick bottom and coat it all with plastic. Will the exposed opening around the entry and exit melt? Thanks all, hope…

I have researched this topic (use of rigidizer to suppress ceramic particles ejecting from the forge), here, and elsewhere, but the no need of rigidizer is new to me. I purchased a new forge (devil-forge), and was concerned about the coating they provided for the forge, it appears to be a clay colored refactory coating. Contacted the manufacturer re: rigidizer not included. They said, the refractory coating they provided is adequate - you do not need rigidizer to prevent dissipation of ceramic wool particles, it will 'fuse by itself' when the forge is heated. (their actual statement is: 'ceramic wool hardens itself when it is heated for the…

When I built my gas forge a few years back, I didn’t realize the extent to which the dragon’s breath would impinge on the ends of the steel shell, especially when the doors are closed. As a result, there’s been a lot of damage: So, I cut away most of the damaged steel: And after picking out some damaged bits of Kastolite 30, teasing out the kaowool from under the edges of the shell, and dampening everything with water, I rebuilt the ends with Greencast 421: I also built up some damaged areas on the inside, especially a missing chunk of Kastolite on the wall opposite where the burner port and a crack that had opened up between that wall a…