10 months ago
once to the last metalworking post confused and finding the title hard
to read. Hopefully when trolls realize its real metal working content
they can move on to other topics they will find more enjoyable.
On Topic Portion: After Jim Wilkins comment about abrasive discs I stuck
one of my little mandrels in a drill press and cranked up the RPM. The
discs were part of a batch I bought from Benchmark Abrasives. Suface
conditioning pads. Not knowing which would work best I bought a pack of
two different ones. A "red" one and a "grey" one. For some reason I
thought they were green on the website. The grey one felt way to
coarse, so I tried the red on. Working under the head of the drill
press is a little awkward, but it works ok. You are working blind
except when working on the side of the disc, but its not to bad. It
will deburr the part, and leaves a generally nicer finish than sand
paper. After just three molds (6 parts) the disc was about toasted.
Being a cheapskate I could get a little more work out of it, but that
wasn't really my goal. My goal was faster, cleaner, and more efficient
deburring. Given that it wore out so quickly it also left a lot debris
on the parts. I'll rinse them all anyway before going back on the
machines, but they do need to go back on the machines. The back side
needs customer name and catch phrase engraved yet. Still there was a
lot of red abrasive bits all over everything.
Randy and Jim both mentioned belt sanders. I prefer to call them belt
grinders, because that's the way I use them. Recently I made some
repairs on the little Harbor Freight 1x30 bench top belt grinder.
Mostly I just adjusted it and tightened up a bolt that holds the
tensions tracking assembly in place. I was not hopeful that it would
run the surface conditioning belts any better (at all) than it did the
first time I tried them, but I tried one anyway. I had gotten a couple
each of two different ones. Also from Benchmark Abrasives. I selected
the one that felt finer (grey/green this time) and left the red ones in
the drawer. It was difficult to get on. I had to wrap my arm around
the machine and pull it against my body to pull the tensioner far enough
forward to get the belt on. After turning it by hand a couple times I
plugged it in back and and turned it on. No pleasant surprises there at
all. It still would not turn the belt. Just being a little obstinate I
started spinning the large lower idler wheel by hand with a finger tip.
A little help didn't get it going, but I noticed it would turn fraction
of a rotation before stopping. I decided to manually spin it a little
faster. When I pulled my finger to safety the belt grinder kept going
and then it sped up. It wasn't as quick as normal, but within a second
or two it was turning at what visually appeared to be its normal speed.
I still was not hopeful, but I wanted to see what the conditioning belt
would do. I don't think I really ever thought about the machine again
as I deburred moderately complex edges on 7 more mold (14 more parts.)
Straight edges were easy, but walking round edges for hinge bosses
around on the belt and cleaning up inside and outside corners was pretty
easy to control. Sure it looks like it was done by hand but it looks
good. Those parts are not all covered with a large cloud of abrasive
debris. There is some I am sure, but nothing like from the little disc.
The belt looks used, but its not worn out. I am sure I could do
atleast another dozen parts with it. More since I'm a cheap skate and
I'll push it to the end. After the little belt grinder came up to speed
I don't recall it seeming to bog down one time while I was using it.
I mentioned two companies previously in this post purely for reference.
So people wouldn't find it odd if their Combat Abrasives or their Wen
belt grinder performed differently than I described. I am not endorsing
or putting down any of the companies named. Just describing how the
products I used performed.