gingery home made lathe
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rhankey
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Have you seen this thread: http://www.homemodelenginemachinist.com/f37/gingery-lathe-15403/
scooterman
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At present, I am building a lathe 9X20, using some of the methods that are described in Dave gingery's books. So, far the build has been on again and off again as I proceed with updates on my furnace building and pattern building methods. One thing that is a set back for most is the would be builders is the green sand casting methods, from my experience, either the moulding proceedure is spot on or not. I started using the "lost foam" method for casting the various parts for my design as the foam allows for some complicated shapes with out building patterns out of wood, I built some patterns that took hours and hours to complete, only to have the final product befeld by something going south with the casting. Not the case now! There is a very good tutorial on lost foam casting by David Cush, once I find that again I'll post the address. Machine building is not as popular as it once was, none the less, its very rewarding.
scooterman
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The site for the lost foam casting tutorial is, Build Your Idea.com and this site belongs to Dave Kush. What he builds are parts for his home made CNC milling machine projects. He has an e-mail address and will offer hints and suggestions about his process, another person that has built Gingery type machines is Rick Sparber and he also can be found at RickSparber.com. Hope this is of some help! Best to all. Scooterman
cameneft,
I built one about 20 years ago and since then made some improvements mostly to deal with its tendency to chatter. I can get pretty good accuracy and I can fix anything that goes wrong. It requires scraping to build (even if you have a friend with a mill). Find someone, or a video to show you how easy scraping can be - that was the bottleneck for me. I learned a lot building it (since I knew nothing when I started). If you are in a hurry for a lathe and already know a lot then you might be further ahead getting a part time job and buying one for the time it takes. Tim
I built one about 20 years ago and since then made some improvements mostly to deal with its tendency to chatter. I can get pretty good accuracy and I can fix anything that goes wrong. It requires scraping to build (even if you have a friend with a mill). Find someone, or a video to show you how easy scraping can be - that was the bottleneck for me. I learned a lot building it (since I knew nothing when I started). If you are in a hurry for a lathe and already know a lot then you might be further ahead getting a part time job and buying one for the time it takes. Tim
Camnefdt,
I might add that I found the casting process fun and pretty easy for making the Gingery lathe. If I did it again, I would make the bed with a foam casting becasue it would be a bit easier. I have made foam castings for some things (e.g. for the cylinder and disk of a oscillating steam engine since I didn't want to make a split casting for a one-shot casting) but I like making permanent patterns because you can use them over and over. Also, I made my castings for the lathe when charcoal was $2 for 20 pounds. If you are interested I could tell you about some of the improvements I have made including one or two thnigs I would have done a little differently too. Overall, I can do pretty good work and still enjoy using it! Tim
I might add that I found the casting process fun and pretty easy for making the Gingery lathe. If I did it again, I would make the bed with a foam casting becasue it would be a bit easier. I have made foam castings for some things (e.g. for the cylinder and disk of a oscillating steam engine since I didn't want to make a split casting for a one-shot casting) but I like making permanent patterns because you can use them over and over. Also, I made my castings for the lathe when charcoal was $2 for 20 pounds. If you are interested I could tell you about some of the improvements I have made including one or two thnigs I would have done a little differently too. Overall, I can do pretty good work and still enjoy using it! Tim
Camnefdt,
You need to use DRY sand for the lost foam casting process. I use very fine sandblasting sand. In order to have the force of the molton metal get into all of the small sections of the foam pattern, the pouring sprue needs to be much larger than one used for wet green sand. I make a sprue from the foam wrap it a few times with masking tape attach it to the end of the part, and bed the foam pattern vertically in a trash can. This requires a lot more melt than green sand casting, but works well. BE CAreful, and good luck with the casting.
ART
You need to use DRY sand for the lost foam casting process. I use very fine sandblasting sand. In order to have the force of the molton metal get into all of the small sections of the foam pattern, the pouring sprue needs to be much larger than one used for wet green sand. I make a sprue from the foam wrap it a few times with masking tape attach it to the end of the part, and bed the foam pattern vertically in a trash can. This requires a lot more melt than green sand casting, but works well. BE CAreful, and good luck with the casting.
ART
thanks art for the reply
just trying to understand the lost foam way of doing things, so using dry sand, would i be able to just take the sand out of my garden sift it for any larger stones etc and use that? without coating the foam in anything?
just trying to understand the lost foam way of doing things, so using dry sand, would i be able to just take the sand out of my garden sift it for any larger stones etc and use that? without coating the foam in anything?
scooterman
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camnefdt,
I'd would suggest using clean sand such as the packaged types offerd in building supply stores and or home improvment stores. You will get very nice castings surface and integrually if you use the dry wall plaster slurry/over the foam pattern prior to pouring the melt. The plaster "shell" actually supports the foam during the pour and pretty much prevents sand inclusions and rough surface texture. If you saw the Dave Kush website you will notice his comments on the plaster process. Another tip is the use of "fluid sand" to make sure the sand finds its way in and around all surface areas of the foam pattern. It envolves the use of a copper tube drilled with small holes and bent into the shape of the container holding the sand. The pattern is held in posistion while the sand is being poured in and then low pressure air is applied to the tube, as the container fills the sand is "moving" in all directions" and when the container is full the air is shut off. Gentle tamping will cause the sand to "set" in and around the pattern, also the use of the "hydro" fill will help as the static head pressure of the melt causes less chance of thermal stall with in the pattern. Try some simple shapes first, always make sure the plaster slurry is set and dry. You'll be surprised at the consistant finish in your parts! good luck be safe!
I'd would suggest using clean sand such as the packaged types offerd in building supply stores and or home improvment stores. You will get very nice castings surface and integrually if you use the dry wall plaster slurry/over the foam pattern prior to pouring the melt. The plaster "shell" actually supports the foam during the pour and pretty much prevents sand inclusions and rough surface texture. If you saw the Dave Kush website you will notice his comments on the plaster process. Another tip is the use of "fluid sand" to make sure the sand finds its way in and around all surface areas of the foam pattern. It envolves the use of a copper tube drilled with small holes and bent into the shape of the container holding the sand. The pattern is held in posistion while the sand is being poured in and then low pressure air is applied to the tube, as the container fills the sand is "moving" in all directions" and when the container is full the air is shut off. Gentle tamping will cause the sand to "set" in and around the pattern, also the use of the "hydro" fill will help as the static head pressure of the melt causes less chance of thermal stall with in the pattern. Try some simple shapes first, always make sure the plaster slurry is set and dry. You'll be surprised at the consistant finish in your parts! good luck be safe!
Camnefdt,
The plaster slurry method works well. I have also just painted the pattern with 2 coats of latex paint which forms a barrier between the foam and sand. Also to join all the pieces of the foam together I use J B Weld quick setting epoxy. The solvents in epoxy do not disolve the foam and cure quicker than wood glue. Make sure whatever use use it is thoroughly dry before casting with molton metal. Good luck
ART
The plaster slurry method works well. I have also just painted the pattern with 2 coats of latex paint which forms a barrier between the foam and sand. Also to join all the pieces of the foam together I use J B Weld quick setting epoxy. The solvents in epoxy do not disolve the foam and cure quicker than wood glue. Make sure whatever use use it is thoroughly dry before casting with molton metal. Good luck
ART
