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gr8life
12-31-2011, 11:40 PM
I finished a job today that I started a number of days ago. I do this job a few times a year.

Got it packed up to ship and started to think about all the scrap I have. I started w/ 48 feed of 6061 alum. 1.25 in. dia. Cut each piece to 4.04 in. long +- .005.The job calls for a 35/64 hole most of the way thru & a 7/16 - 20 thread on the other end. Most of the diameter is reduced to .90 in.

The original 48 feet of stock weighed about 69 pounds and the final product weighs about 19 pounds that is about 50 pounds of swarf and a few end lengths of an inch or so from the saw. Alum. chips have almost no value here so they wind up in the land fill. What a waste but the job pays well.

Anyone else do jobs like this?
thanks
ed

armedandsafe
12-31-2011, 11:59 PM
Steel threaded rod, 7/8-14, 2.5" long with a 0.440" hole 2" deep, then 3/8-16 through hole, in the other end. Cold rolled steel 1/2" rod, 2" long, with 0.214 hole 1/2" deep on one end, 1/4" hole 1.5" deep in the other. Bolts, 3/8-16, 3.5" long, head cut off, unthreaded shank reduced to 0.160"

I haven't done the math or weights, but it sure seems my #3 son is getting a lot of recycle weight. :D

Pops

Deus Machina
01-01-2012, 12:38 AM
I've done a few things like that. Valve pins, for one. Big round piece on one end, tiny skinny shaft.

I've gotten to the point where I will give my friend chips I've mashed down to close into a bucket. He would open them up and use the chips for filler with concrete.

franco
01-01-2012, 01:12 AM
How about making the cylinders for the WW1 type Gnome rotary aircraft engines. They started with a 67 pound nickel steel forging and ended up with a 5 pound 5 ounce cylinder. Machining time was 2 3/4 hours per cylinder in 1910. From memory without looking it up, the walls of the finished cylinder were about 1.5 mm thick. Wonder what the reject rate was?

franco

tmc_31
01-01-2012, 03:23 AM
gr8tlife, how long did it take you to complete each of the required operations? What was the sequence of operations? Not to be nosey but as a newbie, I am interested in how a machinist gets these jobs done. Also what kind of lathe are you using?

Tim

wierdscience
01-01-2012, 09:44 AM
Heh,I've got one job I do every couple months where a 46lb block of 6061 is reduced to a 7lb finished part.Luckily most of the "waste" is lopped off with a bandsaw first so it's not a total loss.

EVguru
01-01-2012, 10:48 AM
Actually describing what it is that I do with my machine tools is difficult, boyond 'making bits for the bikes'.

When people ask what it is I make, I often say 'I make swarf' since that is the major product.

KiddZimaHater
01-01-2012, 11:42 AM
I make O-ring installers for a customer. They're just big Aluminum rings, basicly.
Final dimensions are 6.090" OD x 5.460" ID.
I can't use 6 x 5 tubing because of the 6.090" od.
I can't use 6.5 x 5.5 tubing because of the 5.460" id.
The next available size tubing that I can use is 7 x 5.
Yes, I make ALOT of chips running these parts.

small.planes
01-01-2012, 12:13 PM
I've heard it said several times at various aerospace manufacturers that 90% of an aircraft's original weight never makes it to the runway. They make a lot of swarf...

Dave

photomankc
01-01-2012, 12:52 PM
I have a thread out here where I made a chuck back plate. Started with a 7" solid round of steel that I had to manhandle around and by the end I had a part that I could hold in one hand and three trash bags full of curly razor blades. That's the most extreme example I have done so far.

wierdscience
01-01-2012, 01:38 PM
I make O-ring installers for a customer. They're just big Aluminum rings, basicly.
Final dimensions are 6.090" OD x 5.460" ID.
I can't use 6 x 5 tubing because of the 6.090" od.
I can't use 6.5 x 5.5 tubing because of the 5.460" id.
The next available size tubing that I can use is 7 x 5.
Yes, I make ALOT of chips running these parts.

Ah.. what you need is a heavy duty ring roller and a TIG machine:)

Highpower
01-01-2012, 01:38 PM
Say it isn't so! :p

http://img.photobucket.com/albums/v82/Highpwr/AR%20Lower/th_P8080090.jpg (http://smg.photobucket.com/albums/v82/Highpwr/AR%20Lower/?action=view&current=P8080090.jpg) http://img.photobucket.com/albums/v82/Highpwr/AR%20Lower/th_Drilling_Mag_Well.jpg (http://smg.photobucket.com/albums/v82/Highpwr/AR%20Lower/?action=view&current=Drilling_Mag_Well.jpg) http://img.photobucket.com/albums/v82/Highpwr/AR%20Lower/th_Anodized_rear.jpg (http://smg.photobucket.com/albums/v82/Highpwr/AR%20Lower/?action=view&current=Anodized_rear.jpg)

lynnl
01-01-2012, 03:11 PM
Waste! You wanta talk about waste?

My son in law showed me some titanium blocks, about 30" X 40" X 4" thick, each costing well up in the 5 figures or maybe approaching 6 figures, and weighing around 7-800lbs.
In the final form each one was reduced to about 25 or 30 lbs, or something like that. ...think of a shape like a louvered vent, or gridwork.

Of course that wasn't even chicken feed to the customer.