Anyone out there have a good, quick way to remove the nubs from the sprues
on castings? Right now I just try to saw it off with a hand saw as close as
I can to the piece and then use rubber wheels or files to remove anything
extra. Just wondering what you all out there use - if there is any special
tool that will do it quicker.
1 Like
We use end nippers or flush cutting wire cutters and catch the
gold dust from the rest…
Dear Jill and Richard, the only sure way I know of removing sprues
(and saving as much re-usable precious metal as possible in the
process) is to saw 'em off ‘n’ file 'em down. Regards, Rex from Oz
Hi Jill, We remove thousands of sprue nubs using a 8" expanding
lapidary drum. We can change belts quickly. We use anywhere from
80-200 carbide grit. At the bench for smaller areas we use 7/8"
carbide separating discs stacked 2 or 3 on a small mandrell with a
foredom. J.A.
I use a $79 belt/disc sander for sprue removal. One of the best
investments that I have ever made.
Bruce D. Holmgrain
e-mail: @Bruce_Holmgrain
http://www.goldwerx.nu
phone:: 703-593-4652
Anyone out there have a good, quick way to remove the nubs from the sprues on castings?
I have used a mizzy heatless wheel, a coarse file and flat sided
cutters. But a careful sawing is always the best method for me,
then a quick file I tripoli. Joy
Hey . If you are doing a production thing I found that an 8 in
expandable drum used in lapidary is great for fast cutting down of
all kinds of things in the shop it even sharpens if you take your
time and do not heat up stuff to purple (Iron). But it cuts gold
and silver sprue nubs fast and real nice but like most anything
else you must practice and do it a few times to get use to it. Also
adjust the speed of the drum to the slowest first then work up to a
faster speed that you are ok with… Try it you might like this (if
you do a lot you will like it). Oh yea! Make sure that you use a
tray to catch the filings that are created… JB…
Hi, We’ve been using a heatless mizzy, then going to Bearatex ie:
3M Scotch- Brite ,light deburring wheel. Good luck and if you find
the 3M wheel becareful it likes finger meat!! 
Matt the Cat @
C.I. A.
Great idea JB. I have also heard of this used especially for
silver which heats up fast. The real advantage to this set up is
that most Lapidary units allow for water cooling. Gold may be
another consideration, yet I don’t see why one couldn’t catch the
water and lemel in the splash pan and waterbucket below the
grinder.With this set up, you would breathe less dust.
Sounds good to me,
Don Wollwage
Hi, I think the mizzy wheel is too harsh and the silicone carbide
belts on 8" expandable rubber drums won’t get into tight areas. I
like to cut sprues off with #2 sawblade, then secure the item in my
ring clamp (whether its a ring or not) and get after it with a
white silicone softie in the flex shaft. By using the ring clamp to
hold the piece, you can run the flex shaft at high speed without
burning your fingers when the metal heats up. This method works
well for removing both the sprue nub and mold parting lines all at
once. Just be sure to keep the wheel moving at all times to avoid
giving the surface a wavy appearance. FWIW hope this helps.