Jump to content
I Forge Iron

Not getting enough heat with my brake drum coal forge


CrazySmithy

Recommended Posts

Hey guys! I've posted and talk about a propane tank enclosed forge me and my dad are building, but now I have some questions about our old brake drum forge we built maybe 4 years ago.

It's pretty open, (Check pics) though it holds a decent enough amount of coal. But the problem is that I'm not getting enough heat. It take a long time to heat up the steel, and it's hard to heat up even just a rail road spike to bright orange. So... What can I improve on this forge to fix this? We only have the one pipe at the bottom of the forge for airflow with a little door at the bottom to let out xxxx, and I am using a little electric squirrel cage blower as a bellows. I think it might be possible that the air is hitting the metal, so it cools it off rather then just blowing the fire. I also am getting a lot of small coke and small clinkers down the pipe, but I think just welding a grate over it would fix it. What do you think? What would help? Do I need more airflow, and the airflow spread out more rather then just the one spot? 

Also, we don't have an anvil but we do have this big 150-200 lb. steel block that's perfect, it just doesn't have a horn. Though, I'm thinking I can just turn a cone on the lathe out of 3"-4" steel bar and weld it on. Would that work do you think?

IMG_9956.JPG

IMG_9957.JPG

IMG_9958.JPG

IMG_9959.JPG

IMG_9960.JPG

IMG_9961.JPG

IMG_9962.JPG

IMG_9963.JPG

Edited by Mod30
Resize large photos.
Link to comment
Share on other sites

Your anvil is what's called a Bridge anvil, it looks great to me. You can make what's called a portable hardy hole and forge a couple of bick's and hot cut's and many other tools to use with it. I wouldn't bother welding one on to the anvil. The forge needs a grate to keep the coal from falling down the tuyere, easy to make out of round stock. Another thing about coal it gives the best fire in smaller chunks than shown in the picture. What are you using to control the air blast? Might want to check this thread for ideas.

https://www.iforgeiron.com/topic/49764-the-55-forge-bottom-and-side-blast/

Also if you haven't read this yet I highly recommend it for getting the best out of the forum. READ THIS FIRST  and browsing the sticky threads to save a lot of headache's. This will help with tips like editing your profile to show your location and how to stay off the moderators radar.

Link to comment
Share on other sites

Okay, cool! Thanks for the tips. I'm thinking I might just use some expanded metal or something for the grate, I've got something lying around. And thanks, I'll need to re-read that, I haven't been on in a while... 

Edited by Mod30
Remove excessive quote.
Link to comment
Share on other sites

What size is your present air opening?   What are using for a blower?

The original 55 Forge used a 2-1/2 piece of auto exhaust pipe for an air pipe. A couple of pieces of 1/4 inch round bar were used for a grate.

image.png  image.png image.png

image.png  

The ash will fill in a cone shape. The brick are to adjust the size of the fire.

image.png

You do not list your location so we do not know if coal, and what type coal, is available to you.

Fuel does not make the fire hot, air makes the fire hot.  I would suggest that you increase the fuel depth so you have a fire ball about the size of a melon. That may mean that you have a fuel depth of 6-9 inches or more deep.

You may want to block off the air inlet and convert your forge to side blast with a 3/4 or 1 inch pipe run horizontally over the top of the brake drum.  The pipe can go maybe 1/4 of the width of the drum.

Screen Shot 2020-01-02 at 4.38.06 AM.png

 

 

Link to comment
Share on other sites

Oh, thanks Glenn! That helps a lot. I just updated my info, so I live in Uintah Utah. Basically Ogden Utah. I have a lot of coal on hand, just from a neighbor's old shed as well as my uncle's shed. It's not a lot, at least for a professional full time blacksmith, but I have at least 2 55 gallon drums worth which should be plenty for now. Though I'm not sure what kind of coal it is. 

As far as the forge goes, I see what you mean. I'm thinking I could weld on some more sheet metal to hold more coal to increase the fuel depth. I have some fire brick I could probably use too. I also just bought some 3/8" bar stock I could use for a grate. 

And thanks for the tip Irondragon, live and learn. 

EDIT: I forgot to mention that I am using an electric blower. Although I do happen to have an old hand crank grinder that I snagged at the same shed I got most of my coal from, and I am curious if I could turn it into a hand crank blower... 

EDIT 2: My dad has just confirmed that it is in fact not a hand crank grinder, but an old movie reel winder. So... yeah. XD

Link to comment
Share on other sites

Depth of fire is what jumps out at me.  Many people try to "save" on fuel by making their fire too shallow and then A don't get the needed heat and B get a way too oxidizing a fire.  Another common mistake is the put the workpiece in at an angle so it gets down where the fire is colder and way more oxidizing rather than horizontally through the neutral to reducing part of the hot spot.

My youngest daughter just moved from Ogden to Okinawa last year.

Link to comment
Share on other sites

13 hours ago, CrazySmithy said:

I have at least 2 55 gallon drums worth of coal

400 - 500 pounds per 55 gallon drum is about 800 - 1000 pounds of coal.  Move it into a 5 gallon bucket for use at the forge. Easier to work with that way.

Extra fuel on the fire is not wasteful as it forms coke and can be used with the next fire.

Link to comment
Share on other sites

Back! Okay, the tuyere pipe was good. I just wasn't getting enough airflow to really light the coal. So I went and grabbed a bellows we made a while ago, and kinda jerry-rigged it to the tuyere. It got it lit, but it kept sucking fire back through the pipe, so I pulled it off and put the blower back on, and at that point it was pushing enough air to heat up the fire. I got the steel hotter then I have before, and I was able to get half of a flint striker forged! I'm incredibly happy, this is the first time I've done this in maybe 3-4 years. It feels good. 

 

Also, question regarding coal: What's a good way to break it down to the smaller golf ball sizes? And how big do you want your chunks to generally be?

Link to comment
Share on other sites

Build a fire from sticks, kindling, wood, and create a pile of hot embers. Then add your coal a little (double hand full) at a time so the coal catches fire.  Remember to plug the bottom of the ash tube T so all the air goes to the fire.  

Once the coal fire is established, adding the gold ball size lumps around the edge of the fire heats them up and they break up easier. a shack with a shovel or tongs is usually all that is needed.   

Please show us what you are using as a blower.  What is the size of the air pipe as it goes into the fire (just below the grate).

Link to comment
Share on other sites

If that was a single action bellows it needed a check valve.  If it was a double lunged bellows the internal valving may be wrong.  Working with 2 single action bellows you can get away without a check valve by leaving and air gap between the nozzles and the tue pipe and alternating such one is always strongly shooting at the tue pipe while the other is inhaling.

Now I have seen folks mis-build a double lunged bellows where they had the middle board moving and the top and bottom stationary---totally missing that one side is always exhaling and so no check valve into the tue pipe is needed!

BTW check valves for organ bellows are described by Theophilus in "Divers Arts" from 1120 A.D.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...