I have some really small/light parts that are made from 1/2" X 1/2"
T-shaped aluminum extrusion that is only .032" thick. The parts are
only 1" long.

The parts are cut off to 1" with a saw that leaves a pretty good burr
on them. I need to remove the burrs but don't want to damage/hurt/wear
the thin .032" aluminum.

Will I be better off with a vibratory unit or just a simple tumbler
(like a rock polisher) and what sort of media should I use? About how
long can I expect the parts to run? I'll be running them in batches of
maybe 500 parts each (this number of parts will fill up about a pint
jar).

How small/cheap of tumbler or vibratory unit can I get away with and is
there a differece between the two as far as the end results are
concerned? Will a light/cheap unit be able to remove the burrs
adequately? Thanks folks.

Joe

wrote:

I have some really small/light parts that are made from 1/2" X 1/2"
T-shaped aluminum extrusion that is only .032" thick. The parts are
only 1" long.

The parts are cut off to 1" with a saw that leaves a pretty good burr
on them. I need to remove the burrs but don't want to damage/hurt/wear
the thin .032" aluminum.

Will I be better off with a vibratory unit or just a simple tumbler
(like a rock polisher) and what sort of media should I use? About how
long can I expect the parts to run? I'll be running them in batches of
maybe 500 parts each (this number of parts will fill up about a pint
jar).

How small/cheap of tumbler or vibratory unit can I get away with and is
there a differece between the two as far as the end results are
concerned? Will a light/cheap unit be able to remove the burrs
adequately? Thanks folks.

Joe



Why burrs? Of course I don't know the part but using the right blade
you should be able to cut an AL extrusion nearly if not completely
burrless. We use triple chip grind blades with negative rake running at
about 7000 rpm to burrlessly cut thin walled AL tubing.

Neither method mentioned is likely to give you good results at removing
the burrs.Burrs tend to mash down and don't want to come off before the
"good" surfaces of the part start getting eroded. Tumbling and
vibrating are better suited to breaking sharp edges.

Others might have different experiences and I don't want to start any
wars here so just take it as "opinion".

Koz

How small/cheap of tumbler or vibratory unit can I get away with and is
there a differece between the two as far as the end results are
concerned?

Got a lathe? You can improvise a tumbler/ball-mill from that, using a PET
plastic jar. You'll probably pay more for the media.

Yeah, I vibratory finish everything, and yeah, what he says, try to
avoid the burr, or you will have to tumble them to a nub

I'm seeing a date with an exacto knife

Koz wrote:


wrote:

I have some really small/light parts that are made from 1/2" X 1/2"
T-shaped aluminum extrusion that is only .032" thick. The parts are
only 1" long.

The parts are cut off to 1" with a saw that leaves a pretty good burr
on them. I need to remove the burrs but don't want to damage/hurt/wear
the thin .032" aluminum.

Will I be better off with a vibratory unit or just a simple tumbler
(like a rock polisher) and what sort of media should I use? About how
long can I expect the parts to run? I'll be running them in batches of
maybe 500 parts each (this number of parts will fill up about a pint
jar).

How small/cheap of tumbler or vibratory unit can I get away with and is
there a differece between the two as far as the end results are
concerned? Will a light/cheap unit be able to remove the burrs
adequately? Thanks folks.

Joe



Why burrs? Of course I don't know the part but using the right blade
you should be able to cut an AL extrusion nearly if not completely
burrless. We use triple chip grind blades with negative rake running at
about 7000 rpm to burrlessly cut thin walled AL tubing.

Neither method mentioned is likely to give you good results at removing
the burrs.Burrs tend to mash down and don't want to come off before the
"good" surfaces of the part start getting eroded. Tumbling and
vibrating are better suited to breaking sharp edges.

Others might have different experiences and I don't want to start any
wars here so just take it as "opinion".

Koz

What exactly are "triple chip grind blades with negative rake"? Maybe
we can improve our cut finish?

Also, I should have mentioned, part of the part has a small notch cut
into it with a router. It leaves a slight burr as well.
The burrs aren't big. Maybe like .020 proud.

Joe

negative rake = tooth leaning backwards a little rather than forwards.
Often found on laminate blades and similar at the local home center but
better to use quality blades if you are making more than a few pieces.
negative rake requires more pressure and generates a little more heat
but gives a cleaner cut on materials that tend to shatter.

triple chip is a little more difficult to describe...Most woodworking
blades are beveled alternately side to side at the top of the teeth and
some have an additional flat top "raker"to clean the gullet to a flat
bottom. Triple chip grind has a flat raker followed by another flat
tooth with the corners cut off. Sometimes there will be a third flat
topped tooth also with a slightly different pattern. The key is the
tips of the teeth are FLAT relative to the blade's circumference so they
remove cleanly without tearing side to side. Beveled teeth will cause
side thrusts which are fine for wood but lousy for metal and plastic.

Triple chip is common..look at the tooth tips at any home center and
you'll see the differences.

Probably didn't describe it well but it's 11pm and I've been workin for
14 hours now. maybe someone else can do better

Koz

wrote:

What exactly are "triple chip grind blades with negative rake"? Maybe
we can improve our cut finish?

Also, I should have mentioned, part of the part has a small notch cut
into it with a router. It leaves a slight burr as well.
The burrs aren't big. Maybe like .020 proud.

Joe