Hello Folks,
I am just a plain old hobbiest with too many hobbies and not much training, if any, in any of them, particularly machining.
Shortly after getting my Atlas mill, lathe and shaper i noticed some of the parts were affected by the dreaded zinc pest.
I needed to make a couple pulleys and the feed change handle on the mill right away to keep it running. I could have bought the used parts on fleebay for a small fortune and these replacement parts might degrade as well.
When i bought my machines it was a package deal.I`d buy the 12 inch 101.07301 lathe, but i had to take the mill (atlas MFC) and the shaper (atlas 7 inch) and whatever tooling that went with them as well. Was i lucky or what ? It was a clean out of a friends dads basement after he died.
The basement had flooded to 18 inches and she was gonna call the junkman to take all the metal.
I told her i would buy whatever she had but she didn`t want my money. She finally agreed to let me give her some money, but nowhere near enough. There was stuff everywhere. Some was beyond salvage but most i could use, stock, tooling and whatever you think would be in a machinists basement shop. This isn`t a tool gloat, it`s just how i came to own an immediate collection.
The point of this is to show what i made. I know it`s all crude by any standards.
I had already put together the Dave Gingery foundry, powered by an old natural gas conversion burner out of an originally oil fired furnace.
I made some rough patterns of the disintegrating pulleys and cast the blanks. It took me a three or 4 attempts to get decent parts. I then read up on turning pulleys and included angles and went very very slowly. This was the first time trying to make something other than swarf alone. I did make a big pile of that, but the pulleys turned out pretty good.
I also needed a new feed handle for the "change o matic" and locking pin and a new drawbar. I know the square on the drawbar is way longer than it needs to be, but that is what i ended up with, and it works. I am too new at this to go for pretty and at this point i go for function.There is also an out of focus single groove pulley i cast and turned as well.
I need to make more parts to replace more disintegrating parts.
I have no pictures of the work in progress as they along with all my foundry pics went with a failed hard drive.
07-09-2017, 11:47 PM (This post was last modified: 07-09-2017, 11:50 PM by Dr Stan.)
Gingerly's set-up is OK for casting aluminum, but it takes awhile to get to temp. When I taught at a vo-tech I built a coal fired casting furnace from an old water heater and eventually plan on a natural gas fired unit here sometime in the future. I also built the copes & drags, a ramming bench out of a 55 gallon drum split vertically then turned horizontally, screen, crucible shank, rammer, spoons, etc.
The are several sites to help the backyard casting enthusiast which also have links to suppliers of small amounts of flux, refractory material, etc. Paxton-Patterson was & I guess still is a supplier, but also very pricey.
Some of the techniques are best described as black arts, so one should pay careful attention. I for one will not cast any structural parts, period. Don't have the non-destructive or destructive testing equipment to determine the strength of a casting.
Also pay attention to your raw materials, especially scrap. Just a drop of liquid can empty a crucible before you know it given the right circumstances. Everything should be pre-heated by placing it on top of the furnace next to the exhaust hole in the lid. Make sure you can ID magnesium and aluminum/mag alloys. Adding either is a great way to set the crucible on fire with a Class D (metal) fire. Don't ask how I know. Aluminum pistons & connecting rods are just about perfect for aluminum casting. Any steel such as piston rings & wrist pins can be removed from the melt prior to the pour.
For reference material the US Navy Foundryman's 3 &2 is excellent. Mine is a reprint from Gingerly so I'm doubtful if its available. However, do a Google search and I'll bet you find a pdf of the document.
And one more thing. Do not, I repeat DO NOT, make pours on concrete. Concrete holds water and will spall sending out shards of concrete. Use a sand bed, or a sacrificial sheet of OSB or plywood. PPE is also a big deal. Aluminum @ 1250 + F leaves a mark and it can be a big one. I wore asbestos when I was casting, neck to toes. Probably need to substitute heavy welding leathers, or such. Foundryman's boots are designed to kick off easily if they are spilled on. They're also expensive, so I always wore Red Wing chrome leather welding boots and paid lots of attention to just what the he!! I was doing.
Nice work. It is always nice to see machines saved from the scrap merchant.
(07-09-2017, 01:12 PM)misterfxt Wrote: ...She finally agreed to let me give her some money, but nowhere near enough...
I know how guilt can be a terrible burden, so I'm prepared to help you achieve a better night's sleep and a clear conscience by accepting the balance of what you considered to be a fair payment. Yes, I know it is a terrible inconvenience on my part but I'm will to make that sacrifice to help you out
I have done some deals with http://www.mymachineshop.net/Default.asp and they have lots of atlas parts, are reasonable and Joel is a great guy to work with. I have a few items myself and always sell them at very reasonable prices. But I've only got a few extras kicking around these days.
My bench is an old solid wood 1.5 inch thick tabletop that i set on short sawhorses. when I`m done the sawhorses fold up against the wall, the tabletop goes the same place. The sand goes into some galvanized trash cans with lids. The homemade copes drags and assorted tools go into the riddle before going into the garage rafters. After the furnace cools the burner goes on a shelf and the body and lid slide into a corner. I ran natural gas to the garage and through it into the alley where i use the furnace. I use a stainless steel flex connector to connect the burner to the gas line. Once disassembled it does not take up much room. I have very limited space. The alley is blacktop and a spill will set fire to it but i keep a bucket of dry sand on hand (Now), the first spill was pretty exciting but i had read Gingery`s book a couple of times (like 8) so i didn`t panic and moved slowly and carefully.
I went to a refractory company here in chicago to ask about refractory cement before i built the furnace.. The guy i was talking to looked in the shop i guess and came back with three bags of 2500 degree mix on a two wheeler, told me it was out of date but i could have it if i wanted it. He threw in a premixed bucket of pointing cement and sent me on my way. Lots of people have been very kind to me over the years.
Like you, I have the Navy foundry books from Lindsay also, Lindsay and i did alot of business over the years. Hopefully he retired well.
I do need to upgrade my PPE, it`s a little lacking.
A friend wanted to help one day and he managed to splash some molten aluminum on the concrete even after being told not to move the crucible near the concrete. As it was splashing out i told him to turn around and by the time the concrete spalled he was facing away from it it and only got hit in the back with a little concrete grit. He also managed to set fire to my bench that day. I gave him the foundry book to read and he was much better the second go round. I had given him all the safety rules beforehand but i guess he didn`t take them seriously. He does now.
I was a little leery about the pulleys when i cast them because of the forces they would be subjected to. I used previously cast scrap for them and stood off to the side when i brought them up to speed on the lathe to complete and when first used on the machines. Never had a problem with them. I know they are ugly as sin but when i finished them i was happy as a clam. Imagine that, i actually made something useful after all.
I still need to make some more parts for the mill like the handles for the gibb lock screws and the overarm support lock screws as well. I think using stock material will turn out just as well or better.
I don`t know about the rest of you. but i often put material in a machine and just whittle away at it getting the feel for different cutters, speeds and feeds. I guess because of the small size and light weight of the machines i can really feel how something is cutting. I don`t know if larger machines allow you to feel the cut. I have gone too far or too fast several times and sent some unfortunate tooling to an early grave. I recently got an old Bport with a tree head and haven`t really had time to do anything with it other than oil the hell out of it and tram the head.
I`ve taken the wise advice of many people (who also have the disease) who wish they had bought machines when they had the chance ,and i got them, even before knowing how to turn them on and I`m glad I did.
Seeing the prices currently asked for the Atlas machines i could never afford them. All told, I now have The Bport,a Logan # 820, Atlas 12 inch lathe, a craftsman 101 series 6 X 18, an Emco Unimat lathe/mill, the Atlas 7 inch shaper and an Ideal brand die filer. I had the Atlas drill press but i traded it for a nicer one. I shouldn`t have split them up, but that`s water under the bridge.
At least there was a little talking about metalworking but I`ll stop now and go back to reading and learning.
You give good advice, especially about casting magnesium and it`s alloys, the thought of that scares me.
