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Donald
 
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Default first milling project questions

I always try to use standard off the shelve parts. A 3/16" x 1" dowel pin is
only is only $6.84/100 from Enco and a .001U/S reamer $4.75. I don't
think an extra 1/64 is going to make a difference in your design.
Don Warner
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"awh" wrote in message
k.net...
I am a new owner of a small metal lathe and milling machine. My first
milling project will be some half inch hinges for a Christmas present.

Materials will be brass for the hinge and drill rod for the pin. I am
reverse engineering a hinge that has a 5/64 inch diameter pin.

My third edition American Machinists Handbook states that for a press fit
the pin should be 0.0075 to 0.001 inch larger than the hole. For a

running
fit the hole needs to be 0.0005 to 0.001 inch larger than the pin.

I plan on using an arbor press to install the pin in the hinge.

By going with wire gage drill rod and chucking reamers I have settled on

the
following:

The hinge pin would be #46 drill rod, 0.079 in. diameter.
The press fit hole will be either a 5/64 bit (0.0781) or a #47 ream
(0.0785).
The loose fit hole will be a #46 ream (0.0810) sizing a hole left by a
5/64th bit.

(dimensions taken from travers catalog)

Here are my questions:

1. Which is easier to work with, Oil or Water Hardened drill rod?

2. Will I be able to use a cutoff tool on my lathe to cut the pins to
length?

3. Are my choices for drill/ream/rod sane?

4. Is there something obvious I should know before starting on this?

Thanks for your help.