Hi Barry;

    First of, my batch was made in a high speed CNC Lathe, and believe

it or

not it was cheaper and faster to turn them out of SOLID round stock

instead of

aluminum tubing.........A length of material (12 ft. long) is fed

through the

spindle and all the turning, grooving and boring operations are

performed with

the last one being the parting (cutting of the part from the al. bar),

so when

the part is mandrel caught, (catched), it's completely

finished....."Piece-O-

Cake" :)

You can do the same thing in an manual lathe, just takes a little longer

:) If

your lathe is not big enough to feed the bar thru the Spindle, cut

lengths of

material which is determined by how far the stock will go into the chuck

(3jaw)

and add 2 inches from the jaws, this means there will be 2 inches

sticking out

from the chuck's jaws.......Face off the stock, center drill, step rough

drill

the bore, do not finish bore. Move on to the outside turnings, grooving,
vebeling etc. to finish sizes. Go back to the bore and using a single

point

boring bar bore to finished size. You can now part the piece by using a

parting

tool, make sure you leave the piece about 1/32 oversize. Next UN-chuck

and pull

the stock out and repeat operations.....If you have, and know how to use

a 4

pos tool turret, and took note of your dial numbers, you wouldn't have

to break

up your set-ups and can repeat this over and over again with no problems

at

all. For facing the parts afterwards, the best thing is to use a collet,

if you

don't, the best next thing I find is to remove the hardened jaws from

the chuck

(I would imagine they are removable for reversing purposes), and mill,

drill to

mount aluminum rectangular blocks in their place, face-off and bore out

a hole

same as the O.D. of the part you want to chuck for facing........This is

a

great project for anybody who want's to learn machining skills.
As a rule, in most machined jobs, fixtures should be avoided as they

actually

take longer to do than the actual parts, even if you're planning to do

hundreds

since you can get a CNC shop to make them for you cheaper.......RIGHT,

Jerry? :)

                                    If I can be of further help, let me

know.

                                                   Butch

Thanks a lot, Butch.

Barry Gardner

 
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