Single use forge

[Ish675]

I'm new to forging. I watched lots of videos and read plenty of material before I decided to try this. I figured a cinder block would hold up to the temperatures required, albeit only one time. Sure enough, it worked. I made a knife from a railroad spike (a fun, and simple, first project). It uses a hairdryer and steel pipe, fed into the bottom of the block, which I  chipped out and sealed with clay from my yard (virginia has excellent clay in the soil). It was filled with cheep walmart charcoal. The first tie was left in the coals too long and liquefied out of the bottom of the block, but after I played with it a bit I made it work! I just wanted to share this, it was made for free. And even if you had to buy everything new it would still only be a few dollars. 

 

 

[ThomasPowers]

A hole in the ground has been used as a forge for several thousand years now; good clay soil just makes it better!  In reality many modern forges could just be considered to be a way to elevate a hole in the ground to a convenient height and to make it more portable.  It is also reusable many many times for no extra cost.. Were you using the cheap chunk charcoal or briquettes?

Please be careful using ties as the creosote in them is a known toxin; I hope you meant spike....

Anyway Welcome to the Dark Side!  The Emperor will be pleased!

[Ish675]

I used briquettes mixed with hardwood lump. The metal sat below the charcoal but it should have been turned to coke by that time ( if what my basic understanding of solid fuel tells me) it got to the metal. I noticed that I got quite a bit of ash got on the metal too (not enough to ruin anything, but a little extra polishing was required to get it off at the end). The hairdryer was complete overkill, even on low, but on the positive side, if I turned it on high real quick it blew out all of the old ash. Due to my huge access to good natural clay, and I'm willing to spend a REASONABLE amount money on firebrick or refractory mortar, but to save money, can good forges be made out of clay, spare brick, cinderblocks,k and just a few firebricks? I don't need anything much bigger than that cinderblock. Most of the designs either require welding ( I don't have access to an ARC welder, I can braze, but that only goes so far) or are large expensive solid fuel forges. As a side note, I don't like working with gas, but I have a large quantity of spent motor oil and was wondering if I could somehow add small amounts of that to a solid fuel forge to save charcoal and help the fire burn more evenly? Some kind of drip into the very end of the forced air pipe, or would even soaking just a few charcoal lumps in it?

[ThomasPowers]

Charcoal does not turn to coke ever!  Coke is produced from coal. Heating metal in charcoal it should be above a thick layer of hot charcoal with more on top of it, so it's in a neutral and not oxidizing fire. I think you were in an oxidizing area which scales up the metal making it harder to clean.  Not attaching the hair drier to the tuyere allows you to get a gentlier  blast by how close and concentric you arrange them.

A good forge can be built from clay and a wooden box.

Don't mix oil and solid fuel you will not get the results you are looking for, oil forges turn the oil to a gas and then burn that like a gas forge.

Do you have access to a drill?  I once built a solid fuel forge with the most fancy tool being a 1/4" drill NO WELDING NEEDED!

[BIGGUNDOCTOR]

Charcoal doesn't coke. Coal cokes. The item should be higher in the fire, too low it is very oxidizing creating lots of scale. Higher up allows the air to be consumed.

Dripping waste motor kill will only give you toxic fumes to breath while not contributing any extra heat. Waste oil is usually run through a forced air burner like a furnace. It is atomized for better burning.

Charcoal, and wood chunks will work fine. Make a sliding gate valve to adjust the airflow from the hairdryer. Read up a bit more on fire management in the solid fuel section.

Where are you located?

 

[Ish675]

I was under the impression that with  wood + heat = charcoal, and charcoal+ heat = coke. I could be completely wrong. You are right about the oxidizing, every time I took it out and gave it a whack a layer came off. I'm looking I to making a clay and brick forge. But I'll play around a little first to get the design right.

[Frosty]

4 minutes ago, Ish675 said:

I was under the impression that with  wood + heat = charcoal, and charcoal+ heat = coke. I could be completely wrong. You are right about the oxidizing, every time I took it out and gave it a whack a layer came off. I'm looking I to making a clay and brick forge. But I'll play around a little first to get the design right.

Yeah, you just misunderstood someone or they misspoke, no sweat. It was probably this statement that got you, however it trickled down. "Carcoal is to wood what Coke is to coal." both have had the volatiles and most impurities driven off by heat and are relatively pure carbon. Charcoal and coke are similar but coke is denser so yields more BTUs per volume.

The heat from a forge will destroy concrete in general and cinder block especially. A soil packed: wood box, old BBQ, V shaped stack of bricks, etc. is more than you really need for a forge. You can make a perfectly serviceable side blast forge in a pile of clay soil on a wooden table top.

Fire management is one of the tricky things to master as a blacksmith. The upside is you HAVE TO PLAY WITH FIRE!!!

Frosty The Lucky.

[Ish675]

I'm located in the US, Northern Virginia,  to be more exact. Everyone here has given some awesome feedback, just reading this I learned a ton. I've looked into some cool clay forge designs too. Is possible to mix clay, sand, and maybe some pulverized brick to make heat resistant bricks? I would mould them in Tupper ware and slowly heat / dry them. I like the idea of an old style wood / charcoal forge made from mostly natural materials.  I still need an anvil too, I found a cheep one on amazon, but I don't work during the winter so cash is tight. A friend suggested that a piece of upside down railroad track might work. I'm allready shuddering at the thought of cutting a thick a** piece of scrap railroad track though...ugh.

[ThomasPowers]

I've got a sister in Manassas and spent 6 years in McLean back in the '60's; too bad it's been so long.  Last time I visited my Sister a developer was bulldozing an old farm and the hedgerow was full of old wrought iron and HiC  agricultural stuff...but that's been 20 years ago.  What you are looking for is *mass* under the hammer; I once used the broken knuckle off a train car coupler---weighed about 80 pounds and had a flat section and a curved section;  or a a friend made a very nice anvil indeed from a chunk of forklift tine---though convincing a Fork Lift service place that it won't be reused can be a trick.   http://www.marco-borromei.com/fork.html   and yes I'm the "Thomas" mentioned.

[Ish675]

I'm in Manassas as well. I grew up nearby, and it's sad to see all the development, the only plus side is with lots of new construction, comes lots of neat new scrap to play with!

[ThomasPowers]

Just remember "A bulldozer is just a huge bunch of anvils that someone has jumbled together to push dirt with".  Many people are stuck on RR rail when it's not the best shape for impromptu anvils.  (Have you looked at the early types of RR rail in the Museum in Manassas?)

[Malice9610]

There is my Charcoal / Coal Forge. 

quite litterally, its just a rough box shape made of bricks, with a fire pot slightly shorter then one standard brick, when full is about 2 bricks stacked sideways deep. 

Stainless steel pipe runs underneath the Charcoal, with 1/4 inch holes drilled in the last 8 inches or so of it, with the end closed off. 

Connects to a hair dryer via a copper pipe into the stainless pipe. 

Total Cost - 14.99 for the hair dryer + 8 dollars for an 18 lb bag of charcoal. ( Royal oak hardwood lump ) 

Super cheap, super easy, will heat a half inch round section of O1 from cold to yellow heat in about 3 minutes, and will melt a blade in 35 seconds if your not paying attention. 

Welcome to the most addictive hobby you could EVER find, I dont think even racing is this addictive, ill let you know once I get my dad away from the track to smack hot metal and drink beer with me. 

[Frosty]

Ish: putting your general location in the HEADER is helpful, mentioning it in a  post or two will be forgotten as soon as another thread is opened.

You don't want to mix clay wet enough to "mold" only damp enough to squeeze into a hard lump in your hand. You've seen a dry mud puddle and how the mud cracks, yes? That's "shrink checking" and is caused by the decreased volume as the water leaves. The basic mix and ratio I like is ( 2-3 pts. sand to 1pt clay) and just enough moisture it can be rammed hard with a mallet or the end of a baseball bat. The sand allows the dry liner to move a little so it doesn't "Heat check" as it warms and cools the sand also allows the moisture to escape easily so you won't get spalling. "Spalling" is water trapped in the liner heating to above boiling causing a steam explosion blowing chips out.

Don't fall into a trap all of us have in the past and get fancy or trying to make the "perfect" forge, heck anything. This is just a fire place, anything that will safely contain your fire is all you need. You want to make nice forged iron and steel not be known for pretty forges do you?

Frosty The Lucky.