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Originally posted by Ken_NJ
How much of the K&S brass do you use? The K&S brass is rather convenient when it comes to push rods etc. Get it from the local hobby store, if there is one. And the small product is easily cut with a Dremel, not ruining the more expensive lathe tooling.
I would think the larger chunks of brass you show in your pictures, only available from McMaster Carr. I have one within driving distance, convenient for pickup at will-call. Last I had something shipped they were expensive, may have changed since.
What about cutting the stainless steel drive shafts we use? How is that on the tooling? Should we stick with a hacksaw? And a Dremel to grind a flat for the set screw?
That all being said, what it the best way to redress the tooling edges on those lathe bits? Stones? And grinders?
Twenty-years ago I shifted from K&S as source for my metal needs, to McMaster-Carr. To answer your question, I have gobs of various K&S rod, tube, sheet, and strip stock.
All the stuff below is K&S. All 260 cartridge brass. Yuck!
However, now I have an adequate amount of the 'good stuff' -- that round stock, bottom-right, is 360 machinable brass -- most suitable for production work.
360 machinable brass end-cuts are kept at the machines for use on items of relatively short length.
Almost all specialty shapes produced for commercial sale were worked from 360 brass, as was the case on the square and gear sectioned length of brass, in foreground, extreme left. It goes without saying that it's good shop practice to keep specific alloys of your metal segregated and identified. Nothing ****es me off more than to do all my lay-out and chuck up chores on the metal only to find I have the wrong alloy on the chopping-block. (I well understand why surgeons sometimes throw an instrument -- handed to them in error -- across the operating room!)
Trouble with K&S is (discounting their copper, tin, and aluminum shapes) is that all thy market is 260 brass, AKA 'cartridge brass', which is hard and awful to machine.
Before our involvement with Mr. Caswell, and later Bob Martin, we were only doing lathe and mill work on an occasional bases (prototype and detail one-off parts) and would put up with overheating and slow feed rates demanded by the hard 260 brass. However, as Ellie and I got into a serious production mode with our lines of WTC/SD's we had to shift to use of 360 brass, AKA 'machinable brass'.
Machine brass is unique in that it is alloyed with a bit of lead, which alters the otherwise 'hard' nature of the brass -- from a brittle, tough to machine alloy of copper and zinc -- to an easy to machine form of brass.
How to tell the difference between the 260 and 360 brass, is this: You do a 'scrape test'. Simply scrape the surface of the brass in question. if you liberate little shards of metal, you have machine brass. If you cannot liberate any scrapings -- or those that are raised are long and brittle -- you're dealing with some form of brass that has little or no lead in it, making that alloy unsuitable for production machining.
Typically, I only use sheet aluminum worked into product that is either pop-riveted or fastened together with machine screws. However, I use a lot of 304 stainless steel round stock for propeller shafts, pushrods, and the like. 304 is a bit low on the Chromium content, has little if any Carbon, so is about as 'workable' as stainless steel can get, which makes it the preferred alloy on this Ranch. You're looking at a box of end-cuts. The stuff I get from McMaster-Carr comes in six-foot lengths and stays, until needed, on the wall.
Stainless can be cut with a small or big carbide or diamond cut-off wheel, or hacksaw. Below are some of the tools used to cut brass, aluminum, and brass.
Only the diamond wheel on the table-saw, carbide wheel on the moto-tool, and hacksaws are suitable for slicing 304 Stainless Steel (SS)
You can machine 304 SS with high-speed tools, be they drill bit, lathe tool, or mill. Tooling steel is rich in carbon which makes it very, very tough, but brittle. Properly aligned and fed high-speed tools go through machine brass like a hot knife through butter, but you have to keep you RPM's and feed rate low when plunging your tool into 304 SS. and it's a good ideal to squirt some 3:1 oil on the work when working the 304 SS.
To re-dress the tips and flutes of mills and drill/boring bits you're best served to take them into town and have a pro do that work. But, for lathe tools: start with a blank (and for this discussion I'm talking high-speed steel) and grind its cutting head to the proper shape with a monster grinding wheel. truing up the edge on a smaller, finer stone wheel. Final honing is done with a stone. An acquired skill! Work at it.
Going mid-evil with the roughing wheel to achieve the initial, rough shape of the tool.
A kinder, gentler wheel is used to make the lathe tool all pretty and suitable for polite society.
No matter how exacting your work on the finishing wheel there will always be a microscopic 'burr' at the cutting edge of the tool. This is knocked off with a single pass over a finishing stone.
Ready for war! Tools in their tool-holders. One set for the little Taig lathe, the other for my big, nasty, Chinese mini lathe (mini being a relative term!).
How did I get to be so ****ing smart? Here's how!...
David
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Awesome awesome information David!! This adds to the repertoire of information you need to know for a task. Examples being rattle can vs air brushing and associated techniques, weathering and associated techniques, scribing techniques. It's early in the AM and I can think of more when my brain is more functional. Thank you for going into detail about this and sorry for interrupting your GD busy work progress! Many things I have learned from you here and in person I have added to my tool boxes of knowledge and skills, and it continues on and on. (Teacher's pet, LOL) Now, only if I can work and play 12 hours a day on my hobbies, and improve on my skills/crafts and techniques. I know this all helps me, I hope others grasp what they see and attempt something they may not have done before.
Thank you, thank you!Comment
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My God, man! Yank your nose out of my butt before you die of hypoxia!
Leave the requisite amounts of diet Mountain Dew at the base of the blood smeared alter and get out!... and don't forget to genuflect continuously as you tread within these, the sacred halls of this, The Chaple of Dave!
(Dismounting my high-horse for a moment)
Seriously, I can count a single finger on one hand (guess what finger) the number of guys I address at this and other forums who is versed in advanced model-building techniques and accomplishments in our field. Yup. That guy is you, Ken. Even at your ripe old age you exhibit the wonderful, childish glee of discovery as you embrace new ways and new mediums; and you have the guts to actually incorporate those newfound things into your current work. I can't tell you how much satisfaction that brings me, Ken.
And you give as good as you take, with good humor and excellent pointers of your own. I regard you as a true peer.
(Now, please excuse me as I desperately try to pry my nose out of your butt).
David
The Horrible
Who is John Galt?Comment
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Well well, we throw these wonderful compliments back and forth! It's a great feeling to take something further than you think you can do. You see something someone else does and say 'I'd like to do that'. All you can do is give it a go and see where it leads you. But you need someone to show you these things, and you proliferate with those ideas. I'll leave at thank you again and keep it up, and I will keep it up as well.Comment
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