I have two large bearing balls (I would say 2.5" diameter) that
I acquired 22 years ago from a Soviet ball bearing factory. For any
reason, I brought them here with me, and could not find any use for
them, until now. As of now, I want to use one of them on my anvil for
shaping round curved things. To that end, I would need to weld on a 1"
square rod to it, to be inserted into the anvil's hardie hole.
The question is what sort of filler rod or arc welding rod to
use. This ball will be pounded on, so the weld filler needs to be
something that would hold up well.
I suspect it will be fine. The exotic alloy content is lower as SS number
goes down, but there is still much more than xx18. Preheat and interpass
peening (air powered chipper or needle scaler) can significantly reduce
stress from cooling contraction. Try to eliminate any slag inclusion or
surface (or root) notches or undercut as these will act as stress risers and
starting points for cracking. (Research Charpy notch test or Charpy impact
Always try to 'make do' with what you have, (or can get easily or free).
All welders are good scroungers.
Good luck, YMMV
Do you know how the stainless steel alloy numbers are allocated?, I
wondered if it was a first come first served basis. I've seen people
post comments like "exotic alloy content is lower as SS number goes
down," before and countered that an alloy such as 310 has a
significantly higher chromium and nickel content than 316 for example.
Can't help you there, Iggy, but that brings up an old story.
My dad was a master mechanic at a mine. He used to bring me ball bearings
all the time, some with the outer and inner race and the brass colored
spacer that would keep all the bearings in place. A lot of them were an
inch or less. Occasionally, he'd bring me some that were bigger.
Marbles was a big thing at school. Shooting from a line at a "boulder"
(large marble). If you hit it on the fly, it was yours, or you could go
behind it and keep all the marbles everyone shot until the next guy hit it,
then he'd get to move up and keep the successive marbles. Occasionally,
when I'd get one over 1" dia., I'd tell everyone that if they hit it, they'd
get a 1" diameter one, of which I had plenty. I'd trade the big ones, but
usually for bike parts and good "stuff".
I wish I still had all those marbles. Some days it was just a drag to bring
home all the marbles or take some heavy "steelies" as we called them to
school. We had bank bags that in those days had little grommets and gold
I was a good marble player, and never suffered from a shortage of marbles.
Ahhhh. A stroll down memory lane. My dad used to bring me miles of
blasting wire, which I would make into electromagnets and small battery
powered electric motors. Those big batteries that were round and as big as
a "40" of beer. Screw on terminals.
Thanks, Dad, wherever you are.
If some charitable organization really wanted to promote interest in
engineering and technical arts they'd just buy up a bunch of bell wire
and give it to science teachers to distribute to interested kids.
Possibly along with directions for making buzzers and motors and whatnot.
To that end, I would need to weld on a 1"
If you have any large carbide drills, I would drill a hole in the
ball, turn the end of the 1" square rod so it is a light press fit,
and press the rod into the ball. Add a tack weld if you want, but it
should not be necessary.
Or anneal the ball bearing and drill with a normal HSS drill. I've done
it to a couple of ball bearings, the largest 1.5" diameter, and it
drilled like a tough steel but didn't present a problem. I heated to an
appropriate temperature and turned the furnace off to allow them to
cool. Next day the balls were drilled, then re hardened, loctited onto
some stems and polished. The use was for some metal spinning tools. The
process produced little scale build up and polishing them back to a
smooth surface was easy.
Don't over-think it. I have a series of different sized bearings from 3/8 to
3 inches welded to 12 inch pieces of 3/8 mild steel rod. I use them for
dinging sheet metal taking dents out of tubes, etc. by using them as anvils
or hammers as needed.
I TIG welded them with ER70S-2 and have never had one break.
I've made a number of texturing dies and and hardy tools using ss balls of
several sizes. I'll echo the advice of another poster "don't over think it"
. Mine have survived heavy pounding and the general abuse that comes along
with such items and have survived. As to the welding, I just grind for good
fit/prep and mig hot enough for good penitration, no pre heat, no peening,
no paint....temper as needed for use. When smithing your work piece should
be red hot (i.e. soft) so it will absorb and be shaped by the forces. This
is why you can use mild steel to make hot work tools even mild is harder
then the claylike hot steel. Longevity can be an issue but it will get the
I would third the opinion to not over think it. Just weld it with whatever
machine is currently closest to you. You are talking about a hardy tool
after all (something you plan on hitting with a sledge hammer), not some
precision jet engine part. If the weld does crack after years of use, take
another 5 minutes to re-weld it.