On Tue, 31 Oct 2017 10:06:03 -0700, "Bob La Londe"
wrote:

"Larry Jaques" wrote in message
.. .

On Mon, 30 Oct 2017 14:01:19 -0700, "Bob La Londe"
wrote:

Sanding by hand is an art. Have you considered a DIY or purchased
wide drum sander?

*** It is, but I have a fair feel for the work I am doing. I'm no expert,
but I get passable results and repeat customers. I would be deathly afraid
of creating gouges or valleys with a drum sander. I sometimes use the flat
platten of a belt sander for hard parts.

I'd think the platen would be as likely to score as a drum sander.


You could build it to fit your largest mold and
then it could ostensibly handle anything that size or smaller.
https://www.pinterest.com/brad2179/d...ander/?lp=true
You could use emery instead of garnet paper.

*** Yep. That was the core of my query. Finding emery cloth paper size
sheets at fair prices. IT HOLDS UP. Some of the sources I've seen just say
coarse, medium, fine. Even though the price may be ok I have to pass on
those. I want to know the grit. Or atleast the grit I am starting with.

Often, you have to ask the mfgr, and sometimes they have to ask their
engineering dept for the micron or grit size. I use 6" x 2" diamond
hones for the most part. $30 for a once-a-lifetime purchase isn't
bad. I wonder how a DMT would work for you. Apparently, diamond
hones are used to hone aluminum bores (unlined--gasp!) in engines.


Additional question: Why do you have to wet-sand?

*** The paper doesn't clog up. I am sanding mostly aluminum. It clogs dry
paper pretty fast. Its also why I hand dress molds between tool changes. I
do not want to significantly change any dimensions. I just want to knock
off the burrs before I place the tool height setter on the mold plate.

Yes, clogging is a nasty habit of abrasive papers. I doubt that
stearates would make much difference with aluminum, but they do with
wood dust on garnet paper. Emery sounds like your winning choice.


If I
ran an ATC or even ATC spindles that used tool holders I could use a tool
height table and only have to dress the mold once at the end of the job, but
alas this is a self paying hobby that turned into a business. Every tool
pays for the next one. Decent ATC spindles cost. I'll have them sooner or
later, but for now I am still making parts.

You're going to CNC mill the surfaces? That seems a bit more serious
than a hand-sanding for burrs.

--
The Road to Success...is always under construction.
--anon