WoodnMetalGuy

Hmm.. How heavy is the dog? 

On 3/11/2017 at 7:10 PM, Frosty said:

How is the wrap closed? If it's laced closed cut the lace. If it's a bag with a draw string cut the string.

The ones used around here are a continuous wrap, maybe 3 or 4 times around the bale, and not tied or laced.  So a knife would need to cut through several layers of net.  -- Dave

Anvil Shaped Object.

Derogatory term for a lump of cast iron...

-- Dave

And here I was trying to think what 'little yellow flower' might be in Latin... 

Found an answer for the coverage question at this site: http://skylinecomponents.com/CeramicFiberRigidizer.html

So if brushing on covers 35 sq feet, I would only need 1/10 of a gallon...

-- Dave

2 minutes ago, Frosty said:

Spray with water, apply another coat of rigidizer to the installed layer AND the contact surface of next one  going in.

Interesting, Frosty.  I hadn't considered that it could be used between layers to glue them together, I was thinking this would just be needed on the innermost face to provide a firmer surface for a thin refractory coating.  -- Dave

Mberghorn - At this page: http://www.sheffield-pottery.com/KAOWOOL-THERMAL-CERAMICS-RIGIDIZER-p/tcr.htm, I found this information:

Physical Properties

Color clear
Solid content, % silica (approx) 28 - 29
Weight per gallon, lb (kg) (approx) 10 (4.5)
Nominal density, (wet), pcf (kg/m3) (approx) 75 (1202)
Maximum temperature rating, °F (°C) 2300 (1260)
Freezing temperature, °F (°C) 28 (-2)
Viscosity, centipoises @ 25°C 4
Specific gravity @ 25°C 1.203
pH 9.7

So, since water is about 8.3 lbs/gallon, looks like they've got about 1.7 lbs of silica in there.

I mix colloidal silica with epoxy as a thickener in my boatbuilding projects, and that stuff is almost weightless - it would take a bunch of it to make 1.7 lbs.  And it's nasty to mix, floating off into the air with little encouragement.

Overall, it may be better to just buy the pre-mixed rigidizer.  My only concern is that at this time in this part of the country, I'm worried about it freezing in transit, which is something that's best to not happen for some reason.  I may have to wait a bit before ordering mine.

I'm also confused about why this stuff would have a shelf life.  I would have thought it would be good indefinitely.  Anyone know?

Also, I wonder what the coverage is for a product like this?  I'm sure I would need less than a gallon. Calculating inside area, less the shelf, plus the ends, I expect to need to cover about 3.5 sq feet.

-- Dave

See this page for some information on the flare: http://zoellerforge.com/flare.html

I made mine out of a section of pipe the size that fits over 3/4".  Made a form with 12 degree taper on the metal lathe, and heated and pounded until it was flared the appropriate amount, which is not much, maybe 1/8" wider at the mouth end.

-- Dave

5 hours ago, Gergely said:

I tried Sketchup, but can't afford to buy it right now.

The free version of Sketchup is sufficient for a lot of design.  And once you figure out a few tricks is not terrible to use.  I just taught myself in order to layout my propane forge design - needed to figure out the shelf for the firebricks I will have instead of a door,  and the support for a little hard firebrick shelf out front, and the frame supporting this all.  It helped in the visualization process, vs. just starting to weld stuff together...  -- Dave

3 hours ago, Mberghorn said:

The first set of .035 mig tips that I bought were advertised as 1/4-28 thread but were actually 1/4-27 thread. Took me forever to find a tap for that and cost me too. Moral of the story is make sure the tips you buy have the thread you want before you buy a 25 pack....

I also ran into that issue, but the threads on the first ones I got turned out to be metric. I have not heard of a 1/4-27 thread before.  -- Dave

I wonder if you'd have better control with a regulator in the feed rather than trying to control the gas with a partially opened ball valve.

And an unrelated question - what's up with all the funnels hanging on the fence in the background?  -- Dave

It's a ways from you, but I got some recently from Continental Clay in north Minneapolis, MN.  -- Dave

So you are thinking 3 layers of the 1" thick blanket?  That's what I will be using in my 14" diameter shell.  I remember that's what Ron Reill had recommended on one of his pages.

The bottom will have 2 layers, topped by the 1" kiln shelf.

-- Dave

I got my quick connects and needle valve from here: http://mbsturgis.com/torch-lp-hoses-and-accessories/quick-disconnect-and-accessories.html

-- Dave

Not that I know it all, but I'm learning...

Regarding sealing the threaded joints, I believe the tape for gas use is yellow, vs. the white that it looks like you've used. The white is for water plumbing. I don't know for sure the difference, may be a different material or a thickness thing?  Anyway, that's a spot where it's just as easy to use the right stuff.  

-- Dave

Xamm940 -

I'm also in the process of building a gas forge, and one thing I'm being careful to do is use gas-rated components rated at the appropriate pressure.

The first thing to know is that ball valves are water (plumbing) or gas rated.  What I didn't know initially was that the common gas rated ones from Home Depot etc. are for appliance gas lines, typically rated at 1/2 PSI.  It takes more looking to find one rated above that.  Looks like the one shown in your photo is rated for high pressure but I can't be sure.

Similarly, quick disconnect fittings come in air (like for an air compressor) and gas ratings.  Finding the gas rated ones is harder.  In your photo the quick disconnect looks like it might be an air fitting, and I don't think you want to be using that in a propane line.

Is that block with the knurled handle a needle valve?  That could be useful in a bypass circuit to provide an idle level flow of gas for when you've taken out your steel and are banging on the anvil, but if you're using that instead of a regulator to control gas flow I don't think that's best practice.

Also, you may want to find this book: "Make: Fire" "The Art and Science of Working with Propane" by Tim Deagan.

It starts out with the very basics and progresses from there, and I've learned a lot, and feel comfortable with my setup.  Recommended.

-- Dave

Thanks for that input, Wayne and Clayton!

17 minutes ago, Clayton M. said:

I would assume you are making a gas forge, so here's my two bits.

I use Kaowool to line my forge. For a coating to protect  the lining I use ITC-100 HT. It works pretty good though I had a interesting  time to try to apply it. Some people say to use a spray bottle, that didn't work so well I ended up using a foam brush and dabbing it on. You can find it on Anvil fire or High Temp Tools.

 

Clayton - I'm also in the midst of building a propane forge, and have the Kaowool and ITC-100 on hand.  But I was wondering if a thin shell of refractory (1/4" or so) over the Kaowool before applying the ITC-100 would be a good idea to protect the fragile wool.  I'm thinking the ITC-100 is going to make a pretty thin layer, and may not provide much protection against ham-handed metal handling.  Your thoughts on that?  Thanks - Dave

Yes, happens to me too in the spring when a warm humid day comes along and hits the cold steel.  As far as I know the only solutions are to keep the humidity out, or keep the steel warm. Hard to do in your situation...  -- Dave

12 minutes ago, Buzzkill said:

Yet another possibility is if that torch was designed to be connected directly to a propane tank with no regulator, then it may actually require higher pressure to function correctly.  I hesitate to suggest trying it without the regulator unless you could put a needle valve and a ball valve for quick shut off between the tank and the burner, but that would give you a better idea.  That regulator also has excess flow protection with auto shut off.  I don't know if that could be part of the problem or not.

That's a good point, Buzzkill. 

Overall, I'm wondering whether this burner is going to work out for a forge  Looks like all the combustion air has to come in through those little slots, and it the area there is pretty small compared to the area in my home-built burner.  Maybe won't be able to get enough heat of of that burner?  -- Dave

20 psi is pretty high pressure.  May be blowing itself out.  Try it with a lower pressure and turn it up gradually to see how it handles it.  Do you have specifications from the torch that recommends what pressure it should run at?  -- Dave

Looks nice - I wonder what kind of steel that is?  Did you have any issues overheating it while grinding it to shape?  -- Dave

I'm just in the midst of a propane forge build and here are a couple photos from mine.  Burner design is from book "Make: Fire" "The Art and Science of Working with Propane" by Tim Deagan.  It starts out with the very basics and progresses from there, and I've learned a lot, and feel comfortable with my setup.  Recommended.

The shell I'm using is 14" diameter and will have 3" of ceramic fiber insulation.  The kiln shelf bottom sits on kiln shelf risers, which are hollow and fit over studs I welded to the shell.

Plumbing has an idler circuit, all gas rated valves, and took multiple trips to Menards before I rounded up all the right bits!

-- Dave

Some older garage door openers used chain in the lift mechanism that is close to if not the same as some bicycle chain.  If you can find someone scrapping one of those you can get about 14 feet of chain that way...  -- Dave

You're too good!  Looks mass-manufactured on that side.  Good thing you left the interior rough so we know they're hand-made!  -- Dave

Those look great!  What was your procedure for grinding the convex back part of the gouge? They look very symmetric, and I wonder if you had some kind of jig to do that?

-- Dave