My brake drum forge - please let me know what you think

[Merlin05]

I made the first iteration of this forge about 20 years or so ago.  I started with an old truck wheel, welded a 3/4" pipe nipple for side blowing and then used it with firewood - all I had at the time.  Wood worked *sorta* ok, but then life intervened and this thing was carried around for 20 years until I decided to modify it for coal.

How it started out; ignore the blower, it wasn't a part of the design then:

You can see the pipe nipple flattened out to spread the air out; it didn't take too long to figure out it didn't move nearly enough air to work, so I ended up just using a big box fan on it when I used it with firewood:

The first mod (besides cutting the nipple out) was to add a drum brake to it and then add a flat plate for the air supply for bottom draft:

Added a pipe for the blower:

And then added an Englander Stove Works AC-16 blower fan.  Although it has dual "Low-High" switches, it blows waaaay too much air, so I had to remove it and replace it with a $2 thrift store hair dryer:

And here it is with it's 2nd forging (1st was some anvil hammer rack brackets); this is a truck leaf spring I made into the working end of a Burke Bar, the subject of another thread in Projects:

 

Please let me know what you think, I appreciate it!

 

[Irondragon Forge ClayWorks]

Looks like an improvement to me. If you want to use the Englander blower, it would be simple to build an air gate between the blower and tuyere, to control the amount of air delivered.

[ThomasPowers]

Or a sliding cover over the intake.

[Daswulf]

Kinda like this. 

[Jobtiel1]

It depends on the blower if you would limit the air intake right? I've heard that its not good for the blower to limit air intake, mine will start turning faster if you limit the air intake, possibly leading to burnout. I'm definitely not an expert, so is it possible to break your blower like this?

~Jobtiel

 

[Daswulf]

Honestly, I couldn't say for all blowers. I only have experience with my dayton blower doing this. Hopefully someone with more broad knowledge can answer that.  

Normally I use a router variable speed switch on the blower. They plug inline with the plug on the blower.  It works for me but I've heard they don't work on all blower motors. 

 

 

[Frazer]

If the motor is being cooled -- or partially cooled -- by the air moving through the blower then yes, blocking the intake can damage it. Moving less air means there is less of a load on the motor (hence it spinning faster), but it also means less cooling.

However, if the motor has a separate fan on it that's used for cooling, less load = fewer amps = less heat build up. So yes, it depends on the blower.

[JHCC]

One option is a valve that doesn't simply block the airflow, but instead dumps the excess air. A simple way to do this is to have an adjustable opening in the pipe that allows that air to escape to a greater or lesser degree as required. Another option is something like this homemade gate valve that I made for my old JABOD forge (alas, no longer in our midst, but the valve worked great):

 

[ThomasPowers]

Most motors have air moving through them to cool them; what he means is that the blower vanes/impellers draw the air they are pushing out through the windings.  So in Daswulf's example you can see that the air does not go through the windings to get to the fan and so no problem choking it.

Working in a shop with forging, grinding, welding going on; I try to source TEFC (Totally Enclosed Fan Cooled) motors for my larger motor needs as 1hp+ motors start getting expensive if you buy good ones and you want to not be replacing them on a regular basis!

(Yes, I cheat and buy good condition top brand motors at the scrapyard when I find them and have several backups for my most used equipment.)

[Frosty]

In most cases if the motor depends on the blower for cooling it draws air from the far end of the motor so unless you block the motor cooling ports the motor is safe.

Blocking the blower intake or outlet reduces the amount of air being moved reducing load on the motor so it speeds up. You can actually feel the difference blocking the outlet on a hand crank blower.

And no, I didn't believe it either till I tried it myself. 

Frosty The Lucky.

[natkova]

Where your ash dump go?

[Frosty]

The pic is a cad concept drawing of the first Bottom Blast tuyere I made. The vertical is 4" exhaust pipe, the horizontal is 2" exhaust pipe. I didn't actually "follow" this drawing I modified it as I went. The counter weight arm on the ash dump ended up less than half that long and was still much longer than necessary. 

I drilled the vertical pipe with a 2" hole saw and used a 4" hole saw to cut the 2" exhaust pipe so they matched closely. The 4" pipe was large enough I was able to weld it from the inside for an easier job of it. 

Since this one I've used an exhaust stack rain cap. Last I looked a 4" rain cap was about $12 USD. Not that making one was hard but for the money buying one that clamps on was worth it to me.

Remember this drawing is just the idea, what I made is different in detail.

Frosty The Lucky.

[Merlin05]

16 hours ago, natkova said:

Where your ash dump go?

There isn't.  A flaw in the design.  Recall that I first put this together before the internet, plus it was used for firewood.

I plan to redesign the forge to a) make it roll-able and b) add the "rain cap" idea (or it's equivalent) that Frosty posted above.

Thanks,

 

[natkova]

Maybe you should put some clincker breaker ia dont know is it posoble to.commbine it with grate over clinckerbreaker.

[ThomasPowers]

Generally clinker will build up on the grate making the clinker breaker ineffective.