The song of the month

Making a Crucible

I needed to make a crucible large enough for some future projects.  It has been a long process, and at no point was a sure I would succeed, but I believe I have.  Coming this far, I think its safe to show how I went about it.

I planned to cast the crucible using a dense castable refractory.  I chose it because of its strength, conductivity and the fact that I have a bag and a half left over from making the furnace.

The first thing to make were the wooden patterns.  

I didn't have stock large enough to turn the outside pattern, which is 10" tall and 8" wide.  Instead, cedar was cut and glued up to form a "barrel."  This barrel was then sanded and carved to shape as it was too big to fit on the lathe!

Below is the internal pattern.  This was composed of glued up cedar 4x4 posts.  I use a lot of cedar.  It is all reclaimed from rebuilding our deck.

Now this was the mold that I cast the crucible in.  It was a wooden box in which I had poured concrete backfill and a plaster face around the patterns.  The plaster would give me a smooth layer that could be sanded and repaired in case the pouring didn't work well.  It came out well, but I'm still happy I used the plaster.  The crucible, after it had set up in the mold got stuck.  Plaster was easier to break away from the crucible than concrete would have been.

With my green crucible de-molded, a kiln was in order.  This is old firebricks stacked up.  Barbecue charcoal is the fuel.

It became rather hot in there...

And the crucible! The patch is from my initial attempt at firing, which I will not speak of.

Ok...I'll tell.  

I tried to fire it in the furnace with the evaporator oil burner.  I'm supposed to be able to control it, but I failed.  It malfunctioned, spat out a huge flame and spalled the crucible a bit.  It hadn't really fired yet, so I patched it. The patch appears to have completely adhered.  

Now for some melting!

I've finally come through with pictures!  The lathe has been mounted since spring break in April.  I have already made parts on it, including siphon burner nozzles for the foundry.  I have faced off a mini anvil paperweight as well to test out the versatility.  An amazing fun machine it is.  These pictures show what will be the permanent home, for now of the lathe.  Since I took these, I have added considerably to my tooling.  I bought from a machinist going out of business and from Fazzio's several large drill bits.  One is 18" long and 3/4" across.  I will use it for drilling my miniature cannons.  That bit realistically needs to be used in a longer lathe though.

I have replaced the belt since this picture and welded a 1/4 socket extension, which fits the 3 jaw chuck, to a handle for a chuck key.  It works great.  I use 7mm hex keys for the 4 jaw.  If anyone knows where to buy real 7mm chuck keys, please leave a comment.

Hope you enjoyed.  I will have lots of pictures of machining and projects coming soon!  School is almost out.

Just showing off another Lathe Picture

I have built a bench and everything for my lathe.  I just need to get around to uploading the new stuff.  Grrrr.  why do I have to be so busy.

My new old South Bend Lathe

Well, I finally found one.  It took over a year of searching, but I finally found a nice lathe within my budget.

Its a model C9W 9" South Bend.  Made in in 1938.  The catalog number is 415-YA

Many more pictures to come within the next two days.  I'll be working on a real bench for it as well.

Stop Online Censorship

Congress is about to vote on the SOPA bill.  Known as the "Sop Online Piracy Act," this bill is like usual misleading.  In reality, it carries an extremely dangerous potential for abuse, letting an overbearing government have access to another corner of your life.

Please go to this site and sign the petition.  I urge you to research this bill and find out what its really about.  Flex the muscles of democracy and fight against this bill.

http://stopcensorship.org/


Sign some other petitions to.  Google this bill and see whats wrong with it, or one day, you might never have that ability again.

Several months ago, I stumbled across a machined steel cannon barrel at a yard sale.  I quickly made it mine.  Just, recently, I have overcome the main stumbling block that prevented any work- the hardness of the steel.

As I bought it, the steel the cannon was turned from was incredibly hard.  None of the drill bits I had on any speed would even bite the metal.  I decided it was time to try and anneal the steel.

I built a fire in the forge and put the cannon over it, with firebicks all around.  The polished surface readily showed the temper colors that appear on steel heated to a few hundred degrees.  The point is not to make the steel glow, but to blue it.

This was successful.  With the steel annealed, I was able to drill the vent hole and two shallow divots that provided support for the trunions, which were later welded in place.

The steel has turned a nice dark color.  I like it.

 This is one of the wheels in progress.  I turned some wood "hubs," drilled holes and inserted wooden dowels.  The next part will be the actual rim.

 This is the carriage propped up slightly.  It will actually be about 2.5x higher.  The wheels will be about 7" in diameter to give a sense of scale.

 You can see the vent in this photo.

More to come!  The carriage will be completed and stained soon.  Come back and check soon.