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Best way to machine SS rings?

MwTech Inc

Titanium
Joined
Feb 6, 2005
Location
Fishersville VA
need to make 20+ rings from 303 SS.
approx 2.00 od 1.625 id .500 wide.
What is the fastest way to "remove" the center?
Will be using a Cincinnati 17" with coolant.
Would you feed from the carriage/toolpost or from the tailstock?
Will need to finish to exact specs after id is roughed out.
Thanks
 
Does the quantity justify the cost of new tooling to save a bit of time over using a normal HSS drill? If it does then yes a carbide spade drill, or an insert drill running at faster SFM would be quicker, if the machine handles it. If your toolpost securely pins on the compound then it may work ok, if it doesn't I'd be worried about it twisting under the load of pushing a spade drill. Then again its only 303...
 
It depends on how you're planning on making the rings. If you're making them from blanks cut slightly over .50 in. long then trepanning the center would be easy and avoid having to make that rough hole into 100% chips. It's faster and takes less power than drilling through solid.
 
I do alot of 316ss and I just push through with a good HSS drill in the tailstock, then clean the bore to size with carbide insert boring bar. The carbide spade is great if you don't get any chatter, but it can fracture under vibration. For 20 pcs. I would try the HSS drill first, just keep plenty of coolant on it and always keep it cutting.
 
There are 2 types of holders.
Letter series (1 hole mounting)
Number "T-A" series (2 hole mounting)

From the TAASC-05 allied catalog as follows:
(check my math)
C5 CARBIDE BLADE TIN COATED 150-210 SFM
376 rpm low side
.014-.016 IPR feed recommended....
Even .005 IPR =102 turns of the spindle to go .510 along the carriage.
Looks like less than 1 minute to poke the hole.
Super cobalt would be less cost, maybe 2 minutes as opposed to 1.
Size down a thirty-second or 2 for finishing the bore.

I wanna see a trepan tool do it faster....

YMMV

How big of a twist drill are we talkin here ??
Agreed that an ole twist drill will do the job for 20. But one pass from solid with a 1.500 twist drill?
If not then its more time...
Once you get set up with a spade holder you may never go back .
Your lathe sounds like it has enough ass to do the job....
everything must be rigid and 'right'...your tool post must be locked solidly, cannot swivel!
 
DK
So a spade leaves a "finished" bore, I mean a decent finish?
I'm not doing aerospace stuff. :)

Lathe is a Hydra shift with newly rebuilt clutches(all plates, dogs, etc) and the lathe is is excellant shape other wise.
Using a KDK toolpost.

Thanks for the info on the speed etc. Gave me good info.

How much effort is needed to push bit?
Thinking spade bit in tailstock, finish boring with compound as the final id is not a standard size


20 units is a starting point, would be more later.

Where to buy Aliied spades????????
 
So a spade leaves a "finished" bore, I mean a decent finish?
I'm not doing aerospace stuff. :)

Depends on lots of things...material, machine, Horsepower available, etc.
Generally, they will leave a decent 'drilled hole' finish unless the chatter problem comes into play. Shank must be as short as possible, etc.



Lathe is a Hydra shift with newly rebuilt clutches(all plates, dogs, etc) and the lathe is is excellant shape other wise.
Using a KDK toolpost.

Horsepower is your friend.....

Thanks for the info on the speed etc. Gave me good info.
How much effort is needed to push bit?
Thinking spade bit in tailstock, finish boring with compound as the final id is not a standard size

Steady controlled 'power' feeding is best....(carriage powered if possible, or from the turret on a turret lathe) ;) Almost forgot....flood coolant is a given....

20 units is a starting point, would be more later.

Sounds like you've paid for the Spade drill already

Where to buy Aliied spades????????[/quote]

MSC, J&L
May the (feed) force be with you.....


dk
 
Thanks DK

My ol W&S #3 won't hold 2" and I don't have a chuck (this confirms the need for one :))
so the Cincinnati will have to do.

I didn't see the Allied name in the MSC cat ,but i may have overlooked it.
 
You don't see many brand names in that catalog.
Spade drills......
MSC 2007-2008 PAGE 156-163.

Jeez
If the godam pages were any thinner you could see thru about 12 of 'em......:rolleyes:

SO... your chuck on the Cinci has 2 piece jaws and yer gonna bore soft top jaws to hold these parts......

2 inch what?
The shank for that drill is most likely 1-1/4 or 1-1/2.......
A W&S without a chuck might as well be holding a boat still or a dock down at the lake.....

Can you source "hollow bar" ?
Because of outrageous prices, usually -never- is cost feasible to use it over poking holes in solid.

I'd make them pay for the proper material
Or the 'other guy' will just make it from solid for less.....

dk
 
Seems like using minimum material would be most time efficient and less expensive.

Guess hollow bar has a lot of fabrication costs "baked in" as its DOM and not ERW. I haven't bought that much so I can't speak for pricing.

There's a 1-5/8" solid bar "hiding" inside there!
 
How about using a Rotobroach- type cutter in a lathe? I've not tried this but would be interested to hear from anyone who has...
 
I have no idea what your quoted price and aloted time is, but it's not the sort of job that is ideal for a lightweight engine lathe with a small spindle bore and limited horsepower....

For this type of work I used an old W&S 3A...
Drill with the turret, Allied HSS Spade drill is perfict.. Cut the OD to finish size at the same time...
Cut off..
Depending on tol, finish the ID in bored soft jaws on the engine lathe...or in the W&S before cut off...

Now if your up aginst someone with a Barfeed CNC lathe, they will finish this job before you have 5 pc done..

Good luck
 
DK
"SO... your chuck on the Cinci has 2 piece jaws and yer gonna bore soft top jaws to hold these parts......"

Yes 2 piece, no boring soft jaws. Finish size is under 2.00


2 inch what?
2" diameter stock,, 3's only good for 1.50.

The shank for that drill is most likely 1-1/4 or 1-1/2.......
A W&S without a chuck might as well be holding a boat still or a dock down at the lake.....

Yea I know, no chuck stinks. Need to get motivated and get one.
 
If you cut blanks approximately 1/2" thick, you could punch out the center on an ironworker to a little over 1" (depending on the ironworker and dies available).

Your 3-jaw could be used to do the rest of the machining.

Roger
 
To me that type of job should be from bar and comes off the machine done. Starting from little blanks is gonna quickly add up on handling time, plus you won't get as good a part anyway, maybe within tolerance, but still not as good.
 
If you cut blanks approximately 1/2" thick, you could punch out the center on an ironworker to a little over 1" (depending on the ironworker and dies available).
:eek:..LMAO.....:D
That's the best one yet!!!

Wait......maybe with a .44 mag we could 'shoot' the center out....

"To me that type of job should be from bar and comes off the machine done. Starting from little blanks is gonna quickly add up on handling time, plus you won't get as good a part anyway, maybe within tolerance, but still not as good."

Poppycock...
He's trying to do the job with what he has...
Should he go buy a new Mazak with a 2inch barfeed before he looks at this job?
Parts can be just as good with the blank and chuck method as with bar feed, but would (naturally) go faster with barfeed.
And, IF cutting the blanks on a HF 6" bandsaw.....that isn't the fastest either......but...
 








 
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