BACKYARD FOUNDRY...

[Steve P.]

Does anyone here melt down metals and cast their own parts? I have been watching a few casting video's and think with some practice I might be able to cast up a nice tail panel for my 65' Coronet 500... It would sure beat the snot out of paying $2800.00 for a repop panel.

[73rallye440magnum]

How do you intend to make your mould?

[Steve P.]

Matching wood boxes with male/female guide locks and mold sand. I have never done it, but watching the video's makes it look fairly easy. I think with some practice and some extra hands, I could make my tail panel.

I checked last night after posting above, and the one and only guy that is making these has come down in price to $1500.00... His ad says (Tripple chromed). Now I am wondering how thick chrome is??   It's been a long time since I saw a NOS tail panel for my car for sale, but as I remember, it went well over $3K. 

I am also thinking about making a new console top plate. I have 3 or 4 of them, but all are driver or worse. Also, thinking I could change it to work with an aftermarket shifter. Or I may just be dreaming....

[John_Kunkel]

Are the videos you're watching deal only with the casting process or do they also show the mold-making process including shrinkage rates for various metals?

[Steve P.]

Hey John.. Most of the video's I have seen are back yard peeps. I haven't been able to find any true professionals that want to give up their professional tips yet.. A few have brought up shrinkage, but from what I am understanding you can limit shrinkage by adding a tall stack of molten aluminum. So far I think the best ones use a wooden dowel and build it up higher than the casting box. They pack sand around it to hold the heat in and make it cool slowly. The dowel is removed, but packing it in tight keeps the shape open wide. Also, the better ones also use basically a chimney to allow air out. Some of the castings are pretty impressive.

The best part of doing this is if you screw up, you simply learn from your mistakes and remold and use the screwed up casting to melt down and do again!! They say you can reuse the same aluminum over and over forever and never cause it any harm..

Many are using aluminum pop cans. Others are building bigger furnaces and melting down heads and all kinds of other aluminum scrap. There is a certain amount of crap that gets burned away and floats on top, but what is left is pure aluminum. I have about 50 pounds of cans all crushed and a pile of aluminum window scrap. Some mounts and other stuff that I have been saving for this. 

My tail panel is a large and I have to think, tough part to cast, but what the hell!! Worst case scenario I melt it back down and mold something else. Maybe a cool air cleaner or an aluminum skull for Stu's RatRod.. lol...

[73rallye440magnum]

The chimney is a pressure relief that you should not ever attempt to cast without.

The other column is to compensate for shrink. Just verifying some observations you already made.

Triple chrome plating is the copper, nickel, chrome process.

For $1500, I would not attempt to make my own. I've made castings in the past and your inputs would climb rapidly. Depends on what the experience and an inferior part are worth to you. Once it's done you'll have another couple hundred dollars in plating.

[Steve P.]

The chimney is a pressure relief that you should not ever attempt to cast without.

The other column is to compensate for shrink. Just verifying some observations you already made.

Triple chrome plating is the copper, nickel, chrome process.

For $1500, I would not attempt to make my own. I've made castings in the past and your inputs would climb rapidly. Depends on what the experience and an inferior part are worth to you. Once it's done you'll have another couple hundred dollars in plating.

What are some of the things you have casted?  Pics and info if you have them...

[ws23rt]

I learned some of the basics of sand casting in a high school shop class. It's interesting and fun. Most of the casting failures we had were from larger thinner shapes. The metal needs to be hot enough to flow into all the small places before it solidifies.
I'd say give the process a go with some smaller items to get the hang of it.

Investing in a kiln for the melting seems like a must. What do the back yard video's show as a way to melt aluminum? 

[Steve P.]

Most are building their own furnaces out of steel drums and insulating them with perlite and clay. Some just plain old sand. Most are using propane for fuel. Some are using veggie oil or old motor oil and some are using charcoal with a blower of many sorts.

There is some, I'd say, small investment into building everything needed to have a home foundry, but for most of us on this site, we probably already have many of the tools needed to build everything. Certainly a MUCH cheaper hobby than our cars!!

WS23RT: I have seen exactly what you are talking about with long thin molds. I think a deeper mold box may help that as it will hold the heat longer. More insulation.. Also in one of the video's I saw, they added compressed air to the mix to force in more oxygen and raise the temp of the liquid metal.

There is a guy in Austrailia who builds really strong burners with veggie oil and a squirrel cage blower.. So if propane won't do the job, THAT WILL!!! 

[skip68]

This is all very interesting.   If you do this be sure to start a thread about it.   Start to finish.       

[ws23rt]

Most are building their own furnaces out of steel drums and insulating them with perlite and clay. Some just plain old sand. Most are using propane for fuel. Some are using veggie oil or old motor oil and some are using charcoal with a blower of many sorts.

There is some, I'd say, small investment into building everything needed to have a home foundry, but for most of us on this site, we probably already have many of the tools needed to build everything. Certainly a MUCH cheaper hobby than our cars!!

WS23RT: I have seen exactly what you are talking about with long thin molds. I think a deeper mold box may help that as it will hold the heat longer. More insulation.. Also in one of the video's I saw, they added compressed air to the mix to force in more oxygen and raise the temp of the liquid metal.

There is a guy in Austrailia who builds really strong burners with veggie oil and a squirrel cage blower.. So if propane won't do the job, THAT WILL!!!  

I agree that most of us that might give this a go already have most of the ingredients needed.--tools, scrap, and the like. The other ingredient is the challenge and adventure of doing something new for ones self. That in my mind is an addition to the investment but it's more like a benefit. Coming away with a part and the accomplishment.

About casting long thin parts in a sand mold.---I may be wrong about this but my thinking is the mold is room temp. to start with and the metal will need to travel through narrow passages to reach everywhere losing heat fast. A deeper mold would hold heat longer for slower cooling but if the metal doesn't get everywhere quickly it could clog.

BTW I have many thousands of hours and dollars invested in doing stuff for myself and feel like I'm left with a good benefit for my investment.

This back yard foundry topic has my interest again.--- Now what do I need that is impractical to machine?---

[TheAutoArchaeologist]

Here's a neat article that we did in Hot Rod about casting your own stuff.

http://www.hotrod.com/how-to/additional-how-to/1306-simple-aluminum-casting/

Ryan

[mrsskip68]

Any concerns about possible toxic fumes??? 

[John_Kunkel]

You have to appreciate the difference between simply casting parts and casting replica parts. In the former, shrinkage rates are pretty much irrelevant but when you're trying to make an exact replica it's very important.

I have a friend who is a master T&D maker and pattern maker; I was hanging around his shop one day when I noticed several 12" rules lying on his bench and every one was a different length. He explained that each one was for laying out the pattern for metals with a different shrinkage rate.

Casting something as large as a tail panel isn't for a home shop IMHO.

[ws23rt]

I agree with John on this. If you are hoping for a nice tail panel from a learning experience like this, I see lots of frustration instead of fun.

Those "shrink scales" mentioned are kinda cool to hear about. I recall seeing them in a catalog and wondered how much trouble they might cause if they turned up in a garage sale (for instance).  They look right because the differences are small.

A bit aside from the topic---One of my jobs brought me to a paper mill in LA a few years back.  (They make paper for sheet rock).
The building is an old block building that used to house horses for horse drawn street cars in LA.
The manager took me up to the roof to show me something special. (The rotten wood stairs with missing planks were scary).

A long covered room had benches and shelves full of wooded forms of parts. Their were pump housings ,impeller shafts, machine frame members, and hundreds of things that I don't know what they were.  All made of wood for sand casting if they had something break down.
These wooded forms were all hand made in the early teens to the twenties. It was like a museum.

It was great fun to get a look at the way factories worked a hundred or so years ago.   If something broke just find the form for the mold and take it down the street to the local foundry and have one cast.

[Steve P.]

Well, I never expected to be able to make an exact replica of the tail panel... (WISH I COULD), but realize I don't have the patience or back to take care of the tedious crap... Hell, not even when my back was good!!   Mostly I'd like to do something for a hobby that won't be expensive and could be fun and different.  Lots of people are casting skulls and pouring molten aluminum into ant catacombs and digging them out for art. Hell, some are selling them on Ebag!  With little in the way of machines, I don't expect to make anything big or intricate. Just think it looks like fun. I surely have enough beer cans to cast something!! I have been saving aluminum around here for a long time.. 

[73rallye440magnum]

I had a casting course during my undergraduate. Just a few small insignias and worthless novelty items.

If you're looking for a fun experience go for it, but don't expect a nice part until you've attempted it about 100 times.

Start with small parts with basic geometry to figure out the basics. Making forms is not easy.

Short shots, porosity, collapsed molds, sink, tear-out. Casting a long thin part is about as difficult as it gets due to heat transfer and fluid velocity during the pour.

Are the individuals in the videos you've watched wearing the correct PPE while pouring?

[Steve P.]

First I want to say that I really appreciate everyone's input on this thread. I highly value every bit of it. I think this could be fun and maybe some day I can become good enough to really put out something nice.

One of the first things I learned is to always have plenty more aluminum in molten state than you will need. Short pours are always going to end up shrinking and messed up. Next is that every part of your readiness is important and just as 73rallye said, lots of practice and learning from each pour.

One of the video's was done by a professional foundry. They make it look very easy and turned out some great parts, but they are full time set up for many pours per day and at a large volume. The major thing I picked up from them is the sand being well prepared with the right amount of moisture in the sand to make it slip and pack without coming apart or leaving a hole where you didn't want one. They also used a large press and shaker to pack the mold or flask.

The best part of learning how to make great molds is everything you screwed up prior can be melted back down without any loss or real extra costs...

I would love to eventually make my own tail panel for my 65', but I am sure if I ever attempt it, it will be after I have learned a whole lot more!! I am wondering if something that long isn't poured from both ends at the same time or maybe the same as they pour for engine blocks, bringing the molten aluminum in from the bottom of the mold? I understand there are a few reasons for pouring from underneath, but don't see a possible way of doing that in a home based foundry.

Also, NO. Not everyone in the video's is correctly dressed for what they are doing, but I am sure they are well aware that they could burn the crap out of themselves.. hahaha....