How long to make this part?

[martik777]

How much time would you need to make this on a manual lathe and mill? Qty of 20
Material 416MX 1/2" round

The .317-.322 hole will need to be bored and a radius machined inside bottom.
I'm not sure what the .9 means on the left drawing view.

 

[extropic]

How much time would you need to make this? Qty of 20
Material 416MX 1/2" round

The .317-.322 hole will need to be bored and a radius machined inside bottom.
I'm not sure what the .9 means on the left drawing view.

It's not .9, it's 6° (six degrees) included angle of the taper. Turn the drawing over.

How long machining would take depends heavily on the types of equipment/tooling available.
You might want to be more specific about the intended manufacturing environment.

 

[Iceberg86300]

That's a max radius call out so technically that can be a perfectly square bottom.

But typically just choose an insert with a nose radius smaller than the max.

Agree on previous response. This will vary wildly depending on a lot of things.

Sent from my SM-N975U using Tapatalk

 

[mmcmdl]

On a cnc lathe , 10 minutes MAX . Drill and tap from one side , flip , machine c bore and turn angle. Throw in an indexing head and drill and tap 10-32s while cnc is running .

 

[Eddyde]

Yeah its hard to say how long to machine, it depends on your equipment, tooling and skill/experience level. Most of the tolerances seem pretty generous so that's in your favor. If I was figuring this for my shop, I'd allow about 12 hrs all in.

 

[markba633csi]

That's a weird way to draw the 10-32 holes- they go all the way thru correct? Wouldn't it be 2 places not 4? My mechanical drawing skill is a bit rusty
Couldn't have picked a more awkward hole size for the small end- have to bore it

 

[macardoso]

That's a weird way to draw the 10-32 holes- they go all the way thru correct? Wouldn't it be 2 places not 4? My mechanical drawing skill is a bit rusty

I would say that because the tapped holes are truncated by the center bore, it makes them QTY 4. If you want to drill and tap 2 holes and then cut the bore to save time, that's your choice, but the part ends up with 4 tapped holes either way.

 

[markba633csi]

Ah you're right- the center bore makes it 4

 

[macardoso]

I'd want to know what the tolerance on the 6 degree taper is. Hopefully not too tight.

I'd start with ground stock and use a 5C chuck on a draw tube. With ground stock (bit extra $ up front) you can save quite a bit of time on tuning the OD and holding concentricity after flipping the parts.


I'd the M10 thread first on all the parts, rough in the thru bore (97% of desired diameter), and cutoff

Then to the mill on a rotary or another fixture to hold the part horizontal to drill and tap the holes.

Finally, I'd install a depth stop in the lathe collet and finish all the tapers and finish the thru bore with a reamer. If you are careful, you can use the reamer to deburr the insider of the tapped holes. I would think you could have the compound set such that the taper could be cut and finished in a single pass with a sharp tool.

If I had to make more than 20, I might consider a custom piloted spade drill that could finish the narrow end bore to tolerance, deburr the tapped holes, and clean up the parted face in one operation.

 

[woodchucker]

Nice layout. Clear, concise, with a nice margin on min/max. I'm thinking the first couple might take you an hour or more. Once you get the hang of it, maybe 35 minutes. But I would still estimate on the high side of 1 hr per. You can use a collet, and feed bar stock in, that way you get a handle on it.