Gingery Lathe - Metal Sand Casting

[sanddrag]

I recently stumbled upon a book series called "Build a Complete Metalworking Shop From Scrap!" by Dave Gingery. The first book shows you how to melt metal and make aluminum castings. The second book shows you how to make a complete working metal lathe from castings. If done correctly, this home-built lathe can be accurate to .001"! I thought this whole deal was really cool. If you are really advanced, you can even go on to make a horizontal mill. And the best part is, is that it can all be made from old soda cans, engine pistons, or any other aluminum you have lying around.

Here's a couple links from people who have built them:
http://www.backyardmetalcasting.com/lathe1.html
http://www.tjanstrom.com/lathe.html
http://incolor.inebraska.com/bill_r/...lten_metal.htm

Do a search for "Gingery Lathe" and you'll find a bunch more.

And here's the book series:
http://www.lindsaybks.com/dgjp/djgbk/series/index.html

Too bad I didn't discover this at the start of summer or I'd have my own lathe right now.

[ZACH P.]

I have heard of those books, and even read one , but from what i saw, you have to be pretty proficent in metalcasting, and have a metalcasting workshop setup to make the equiptment.

[Andy Brockway]

Don't be scared by the thought of 1400 degree aluminum!!

I have built a furnace and have started pouring ingots, the first step in cleaning up the scrap metal. I caution against collecting mounds of aluminum cans. The dross and slag is more than the amount of aluminum in today's cans. Go see your local auto repair shop for pistons, water pumps etc.

Seriously, Lindsey has some very good technical books for filling in some of the additional information you need.

I made my first pour about 20 years ago with a good friend, Roger Richard (His brother Jim is an engineer for the Kilowatz). You will find his name at the Bourke.com website as he built the first working prototype of this engine since the inventor built his in the 50's. We used the lost foam process which does not require casting sand, just regular play sand.

[Adam Y.]

There is also a book floating around on how to make your own CNC Mill.

[sanddrag]

Originally posted by Andy Brockway
Don't be scared by the thought of 1400 degree aluminum!!

I'll have to tell that to my parents. At least my dad melted metal on the stove when he was a kid so he knows what it's like. I tried melting some aluminum last night out it the street with a butane pencil torch and it actually worked. I was only able to melt really small pieces and it didn't get fully molten. I can't wait until my Gingery books arrive.

[AJ Quick]

Wouldn't it be easier, and probably cheaper to just buy a lathe?

[sanddrag]

Easier yes. Cheaper no. The Gingery lathe can be made for about $40. A comparable lathe would cost over $300. Also, metal casting looks like a great learning experience. Last, you can be proud of a lathe you own but you can be prouder of a lathe you built.

[Matt Reiland]

Sanddrag,

I will give you a heck of allot of credit for even thinking about casting your own lathe. The master machinist that taught me how to machine casts engine parts for homemade engines. However the parts require major machining after they cast, not simply a light sanding for clean up. I would be pretty scared to turn a bunch of metal projects on the thing to tell you the truth. Looking at my lathe, the parts are all steel, and they are all machined for precision, and they are all definitely over sized. Even looking at a wood turning lathe that you could go over to sears & buy (Such as this)

http://www.sears.com/sr/product/summ...id=00921712000

looks much more robust that the cast pictures on the site shown.
Looking at the pictures shown, the pieces are the absolute smallest pieces you could use and they don't look like they could hold much of a tolerance without machining them on a mill when you are done. You will definitely learn a bunch about casting in the process of trying to build the thing but also remember that your first pieces aren't going to come out of the molds ready to be mounted on any sort of a precision lathe without some major rework.

Something like this $460
http://www.sherlinedirect.com/merchant.cfm?pid=1&step=4
will probably be more accurate and reliable or you could find one used for even less.

Here is what you can get for even cheaper
http://cgi.ebay.com/ws/eBayISAPI.dll...tegory=13 876 $255

I would strongly suggest you take every precaution for safety when using a homemade lathe or milling machine. They are dangerous enough without having to worry about a part of your machine flying off. Just my $.01 but again kudos for even attempting it.

[Andy Brockway]

For those who are not familiar with the Gingery series of metal working machines....

They are very robust. Dave Gingery and his son provide step by step procedures to build the machines and use the same processes that were used to build lathes at the turn of the century including hand scraping the ways, a dieing art. Castings are used for the major parts with stock material used for the ways and shafts. It is not a quick process but anyone that completes a machine will know what it takes to rebuild other machines.

Many techniques that they teach are perfect for FIRST. I have used several to teach my students how to make parts using a drill press and hand tools.

[sanddrag]

Matt,

I actually was thinking of machining some of the parts after I made the castings since I do have access to some real equipment. I just discovered this thing and have not read the books yet so I'm not quite sure how hard it will be to make. Once I get the books and read a bit, I'll give you an update. I would buy some machines and tooling but I just don't have the money. i do have lots of time that I never put a price on so that works for me.

Also, thanks for your concern of my saftey but I think I'll be alright. I've been working on "real" manual mills and lathes for about a year and a half now and have been working on a CNC mill for a little over a month. No injuries or crashes thus far. And you can rest assured that anything I build will undergo my "reasonably safe certification" test and will be signed off on by me personally.

Also, for anyone looking to buy a metal lathe here is a very cheap little bench unit. I would not trust it to the .001" (or perhaps anywhere close) but hey, it's cheap.

[Cory]

Lol, there must be something wrong with that price.... its over 19 billion dollars as it is written (Unless thast $199 with the model # next to it)

Cory

[dlavery]

Sandrag -

If you really want to get into sand casting and making your own parts, systems, and even complete machines from scratch, go for it! It can be a lot of fun, and you will learn an incredible amount about everything from metallurgy to structural design to machining techniques. But let me offer a few words of advice (which is always worth what you pay for it):

- read EVERYTHING you can get your hands on about the topic. There is a lot of information out there - use it! Check out the "Forges and Foundries" section of the Metalworking Web Sites Index for lots of info. Gingery's designs are pretty slick, but his methods are not the only way to put together a home foundry - some of the other designs you will read about are higher efficiency, cheaper to build/run, easier to make, etc. Check them out as alternatives.

- Once you have read up on the info, find someone who has or works in a small foundry, and spend a day talking to them and looking over their shoulder. You can spend weeks reading about the proper consistency of green sand, and still not really understand what it should be like. Or you can spend ten minutes with someone that really knows, and they will shove your hand in a pile of properly tempered sand and you will get a real "feel" for what it should be like.

- Pick a design, or make up one of your own based on what you have learned, gather the parts, and build your foundry!

- Before you fire it up for the first time, stop, take a step back, and think very carefully about what you are about to do. Is it safe? Do you feel comfortable with the quality of the design, the construction, and how to operate the foundry? Is it safe? Is the area around the foundry clear of hazards? Is it safe? Are you properly prepared if something goes wrong? Is it safe? Do you KNOW what can go wrong, and how to handle it? Is it safe? Do you have the proper clothing, equipment, supplies, and set-up to handle molten metal? Is it safe? (do you catch a theme here?)

- Molten aluminum, or if you go beyond that to molten brass, is nothing to fool around with. If you make a big mistake here, you can kill yourself or someone around you. Please, please, be very careful.

OK, end of lecture. Making up molds and casting your own parts can be great. You can do it very cheaply as well - I built my foundry out of an old 20-gallon oil drum I found in the woods, some scrap pieces of plumbing pipe, a few brass fittings from Home Depot, and some ceramic wool kiln liner from the local ceramics shop. It burns propane (instead of charcoal as in the Gingery design), is naturally aspirated (instead of needing a blower), and whole thing cost less than $100 including the propane pressure regulator. It is big enough to handle a #10 crucible, and the biggest pour I have done was about 18 pounds of brass for a lathe faceplate casting. Here is a photo of the completed foundry, and the burner during the first test firing:



(note: these photos are of a test firing of the burner, not of an active molten pour. Never pour metal on a concrete floor - if the metal spills on the concrete, it can cause the minute amounts of trapped water in the concrete to flash to steam and cause the concrete to spall and explode.)

There are special side benefits to having your own foundry in your garage. First off, periodically having a 2-foot-long jet of blue flame squirting out of the garage door in the middle of the night tends to keep nosy neighbors away. Second, when you get hungry in the middle of the night 'cause you forgot to eat all day while you were working on your robot, roasting a hot dog takes about 14 seconds! But the best part is that you can make custom parts for your FIRST robot. We used the foundry two years ago to make cast motor mounts for the older 3/8" Bosch drill motors. The team learned a lot and we had something unique on our robot that year that we KNEW no other team would have - custom cast motor mounts. But the very best part was that we were able to REALLY recycle robots from prior years - by melting them down and pouring them into molds for the new parts!!!

-dave

[JAH]

Wow, this is awesome! I haven't read the chief in a bit and the first thread I read in a while was this one, wow. I'd love to do that. I'm not sure my parents would go for it...but that would still be cool to make your own lathe or custom parts for the robot. If only the parents had no judgment and let me do all I wanted...

[sanddrag]

Well, I got the first two books in the series and it seems like building the lathe is slightly more difficult than I had imagined. You have to be pretty skilled at wood working (which I am not) to make the patterns. There is also the fabrication of the motor mount and belt drive which is a bit complex. It really can be made by YOU but you need some skills and more importantly, time and patience. Building the foundry and melting and pouring metal into molds actually seems quite easy so I'll give that a try.