cheap fibre blanket

[ironmutt]

has any one used this brand http://www.walmart.com/ip/43062374?wmlspartner=wlpa&adid=22222222227030820775&wl0=&wl1=g&wl2=c&wl3=55974472856&wl4=&wl5=pla&wl6=99933964376&veh=sem if so any thoughts on it its about half the cost but that kinda scares me cause i know you get what you pay for 

(ok looked little more this only #6 but they have #8 for only $83 for 24" by 25')

[Buzzkill]

I haven't used it, but that's the 6 cubic feet per pound density and normally I see the 8 cu. ft/lb pound density recommended for what we do.  That is also available for a little more money.  Continuous use at 1922 F is ok for most forging, but is a little low for welding.  I'd probably only get that if I had no other decent options.

[jagboy69]

Still seems strange to see walmarts name attached to certain items.  If only it was available down at the corner.  lol 

I'm not seeing half the cost here.  And it's rated to 2300 degrees.  Looks fine to me.  I got a roll of kaowool from these guys. http://www.armadilloclay.com/j-k.html

Sign up at Zoro and they send out 20% coupons all the time.  Sometimes they even email a 25% off!

[Frosty]

Buzzkill you have the weight backwards, it's 6lbs. per cu/ft and or 8lbs. per cu/ft. The higher the temp rating is generally denser.

At 2,300f this stuff might work but I don't have to buy a whole roll and 8# Kaowool is rated @ 2,600f. A complete rebuild on my 4 burner adjustable volume shape shop forge takes about 9-10 sq/ft EJ Bartells our local commercial HVAC guys sell 8# Kaowool by sq/ft or give us drops. The only guy in our club who buys in quantity is the professional bronze caster and he buys in rolls and boxes.

All that maundering and I guess I don't know. I have no experience with the product and it's not enough of a price break to experiment with. Not here or now.

I did a quick search, this is the first hit. http://www.neobits.com/unitherm_cf6_1_48x25_ceramic_fiber_blanket_6_lb_p7967861.html

Frosty The Lucky.

 

[Buzzkill]

Not sure what you mean Frosty.  He linked to the 6 and I said the 8 is normally recommended.  Both show the same max and continuous use rating in the description, but they have different R values.

 

Nevermind.  I figured out what you meant.  I was just repeating the info on the site rather than thinking:

 

Ceramic Fiber Insulation, Length 25 ft., Width 24 In., Density 6 cu. ft./lb., Material Aluminum Silicate Fiber, Thickness 1 In., Approx. ''R'' Value 1.06, Max. Temp. 2300 Degrees F, Continuous Use Temp. 1922 Degrees F, Standards UL 723

[Frosty]

11 minutes ago, Buzzkill said:

Not sure what you mean Frosty.  He linked to the 6 and I said the 8 is normally recommended.  Both show the same max and continuous use rating in the description, but they have different R values.

 

Nevermind.  I figured out what you meant.  I was just repeating the info on the site rather than thinking:

 

Ceramic Fiber Insulation, Length 25 ft., Width 24 In., Density 6 cu. ft./lb., Material Aluminum Silicate Fiber, Thickness 1 In., Approx. ''R'' Value 1.06, Max. Temp. 2300 Degrees F, Continuous Use Temp. 1922 Degrees F, Standards UL 723

Ah, I see a typo on the site, I didn't do more than scan the one I opened in a search. That site didn't make that  mistake. I want to take issue I just wanted to help avoid confusion for folk down the road.

Frosty The Lucky.

[Buzzkill]

Looks like NeoBits did the same thing on some of their listings as well, so maybe the description came from the manufacturer that way - or they've found a way to confuse us into paying more for less.

[Frosty]

1 hour ago, Buzzkill said:

Looks like NeoBits did the same thing on some of their listings as well, so maybe the description came from the manufacturer that way - or they've found a way to confuse us into paying more for less.

I think it's marketing guys is all, they're not paid to know anything about a product's specs. Not really anyway. Getting us to pay more for less IS the credo of marketeers. For example, ever wonder about paying good money to filter minerals out of our water then buy vitamins to take care of our mineral deficiencies?

Recently it's been yummy chewable vitamins for adults!

About filtering drinking cooking, etc. water some water NEEDS to be filtered or just avoided entirely. Wanna bet the Admin in Flint Mi. wasn't drinking tap water? We just spent $150.00 to have our well water tested. An earthquake a couple months ago had everything underground stirred up significantly, I was running water through an outside hose for weeks to get the sand and silt cleared.

I'm really surprised the water softener guys weren't going door to door the first few weeks after the quake.

Uh were was I? Oh yeah, marketeers.

[ironmutt]

when i search i look for 1 inch thick 24 inch wide  then compare prices based on equal lenths and shipping  i know  the density and how many layers will affect the performance  and coating it . my main concern is this isnt a name brand more expensive typ like Kaowool but  possibly a chinese knock off i  keep seeing the same quantity from 100 and up plus 30 to ship  on most the sites.  the #8 is 83 with free shipping from zorro thru walmart . i  know that is a lot of product but what i dont use for  forge can go on a shelf till i need it since there are people on amazon selling the same  thickness and width in 31 inch lenths for $50 i can always cut it in 3 foot lenths and sell it off  to make my money back more profit then selling other things and no fear of paternaty test 

 

[timgunn1962]

It looks fine to me, at least for a forging forge or, if you are into knives/swords, a HT forge.

I've not found any discernable performance or handling difference between blankets of the same density and temperature rating from different manufacturers from my hairyarse-with-hammer perspective (this is completely unlike my experience with IFB). There are so many other variables involved with forge building that few of us are ever likely to build to a standard design that allows the differences between blankets to become apparent.

I have found that the higher-density stuff seems to be more able to tolerate the prodding and poking it gets from the workpiece and the erosion it gets from the hot, high-speed gases near the burner.

I would normally go for the 8 Lb/cuft version, not the 6 Lb/cuft, primarily for this reason, together with its better insulation properties. However, in this case the R values are looking pretty odd to me.

I'm used to seeing thermal conductivity drop as blanket density increases  http://www.unifrax.eu.com/web/Audit.nsf/ByUNID/6CCA5961F2AEEBCC85257F950069198C/$File/Fiberfrax%20Durablanket%20S%20EN.pdf

The R-value is a measure of thermal resistance, so I'd expect it to increase as blanket density increases and thermal conductivity drops. For the Unitherm, it does the opposite, based on the 1.06 R value for the 6Lb/cuft and .75 for the 8 lb/cuft. https://www.zoro.com/unitherm-ceramic-insulation-24-in-w-25-ft-cf8-1-24x25/i/G8489634/

I suspect that the quoted R value is based on a temperature difference of around 70 degF and that the heat transfer mechanism is probably very different at typical forge temperatures.

I don't know how great the cost saving is with the Unitherm blanket where you are, but I suspect the overall cost saving will be smaller once you look at the various other things you'll need to build a forge and take shipping into account. 

It is entirely possible to simply line a shell with a double layer of 1" blanket and fit a burner to get a usable starter forge, but it makes for a fragile lining and you need to be very careful about airborne fibers. Some sort of coating and/or rigidizer is definitely a good idea and it gets much easier if you can one-stop-shop for everything. 

Frosty has done some playing around with homebrewed coatings and I've tried some myself with moderate success. The best I've found to date is about a 2:1 mixture by volume of Zirconium Silicate (Zircopax) and powdered porcelain clay, mixed to a single-cream-like consistency with a solution of Sodium Silicate in water. Sodium Silicate is sold in varying concentrations and this makes it difficult to give dilution rates on a volume basis. My best results so far have been with a Sodium Silicate solution density of 1100-1150 grams/litre.

Liberally sloshing on the mixture lets it soak into the surface with the Sodium Silicate penetrating perhaps an inch, The clay/Zircopax only penetrates perhaps 1/8" into the blanket and most of it stays on the surface. You only get one attempt at it so too much is better than too little: once the clay has formed a continuous top layer, it's pretty impermeable and a second coat just will not soak in. 

It needs to be dried well before heat is applied, otherwise it balloons. Once fired, it seems to be reasonably durable (I give it a couple of hours at a temperature I'd consider a good bladesmiths welding temperature; around 1300 degC (2350-2400 degF)). I've not tried its flux resistance yet and I don't expect it to be great. It's certainly not suitable for a heavy-use forge, but seems pretty good for a hobby forge. I'll only really know if it holds up ok in a couple of years.

Zircopax, Porcelain powder and Sodium Silicate are all readily available from pottery suppliers, usually in reasonably small quantities. 

 

 

[ironmutt]

 my plan is to make a half moon shaped with the blanket on all sides with kiln shelf on the botom on top of the seam of the wool then refractory cement  on all the exposed surfaces of the wool  with a split metal door  lined with wool  that opens like french doors with a notch out of the bottom corners of then to alow handels to stick out  the bottom will be 3/8 plate with the moon part being 16 gauge  with a  lip on the front about 2  inches down from the top with wool wraping the lip so when i close the doors its wool to wool makeing some what of a seal at top and sides of doors then having a multipe burner set up  it will be about 18 inches deep with the back end closed off  for now  with a plan to   put a door on the back later  i will takes lots of pics and post once i start  my orignal plan  got scraped cause i had to use the  pipe i had  for a different project 

 

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