Steel recomendations for bandsaw axle
andy
I am trying to repair a vertical woodcutting bandsaw. It is a
Crescent/Delta 20" made in "back in the day"
When I bought it, the upper wheel axle or shaft was scored from a
locked-up bearing. I repaired it by tig brazing and used the saw for
a few years. Just recently, the whole shaft broke. A replacement
shaft is not availble, so I was planning to make a replacement. I
have acess to a lathe, but no heat treating or grinding equipment.
The following links are from my first repair.The shaft is 1" in
diameter at it's largest and about 9.5" long.
http://metalworking.com/Dropbox/saw_shaft_repair.txt
http://metalworking.com/Dropbox/saw_shaft_repair_001.jpg
http://metalworking.com/Dropbox/saw_shaft_repair_002.jpg
http://metalworking.com/Dropbox/saw_shaft_repair_003.jpg
http://metalworking.com/Dropbox/saw_shaft_repair_005.jpg
http://metalworking.com/Dropbox/saw_shaft_repair_007.jpg
I hope to buy a chunk of steel from McMaster-Carr and have at it.
They sell a dizzying array of steel alloys, and I dont' know which to
choose.
Can anyone recommend a type of steel? Can I just machine a shaft and
not harden it? Any and all advice appretiated.
Thanks,
Andy
Lynn, MA
Jim Wilkins
> Hi folks.
> I am trying to repair a vertical woodcutting bandsaw. It is a
> Crescent/Delta 20" made in "back in the day"
> Can anyone recommend a type of steel? Can I just machine a shaft and
> not harden it? Any and all advice appretiated.
> Lynn, MA
That's how I fixed a 10" Delta, drill rod and new bronze bushings.
jsw
Ed Huntress
"andy" <ah...@lynnwatersewer.org> wrote in message
news:e83c2923-fa66-49e3...@e37g2000yqn.googlegroups.com...
4140 would be a good choice. Normalized, it's machineable, if not quickly
machineable, and has a yield of around 95 kips. You can more than double
that in the oil-quenched condition, but single-point turning anything above
about Rc 40 requires some good technique.
Chances are that the normalized condition will do it for you, but if M-C has
some medium-tempered steel, you might try that if you have a rigid lathe and
some carbide tools. Just take it slow.
Here are properties of various 4000-series alloys. Those are good choices
for all but the most extreme applications. Good luck.
http://www.matweb.com/Search/MaterialGroupSearch.aspx?GroupID=230
--
Ed Huntress
Ned Simmons
I'd use "Stressproof," which is a tradename for AISI 1144. See the
bottom of McMaster p.3605. You'll have to start with an oversize piece
if the 1" dimension needs to be close to 1.000.
My second choice would be 1045 TGP (turned, ground & polished), but
only if starting with an accurate OD is a help. McM p.3601
If you want something even stronger, you could use 4140 pre-hard, but
at the expense of stability and machinability. McM p.3609
--
Ned Simmons
Joseph Gwinn
<e83c2923-fa66-49e3...@e37g2000yqn.googlegroups.com>,
andy <ah...@lynnwatersewer.org> wrote:
Was the shaft ever hard? Try filing the end remote from the TIG brazing.
There is a good chance that the shaft is ordinary mild steel, as Delta
was making these by the million for small dollars. If mild steel, a
leaded steel (like 12L14) would work dandy.
Touch the old shaft to a grinder and look at the sparks. This will tell
you if the shaft is alloy steel.
Joe Gwinn
Snag
> Ed Huntress
I used normalized 4140 for swingarm bushings for my motorcycle . Slow speeds
, light cuts , and normal feed rates . Dwell in one spot too long and you'll
be grinding the hardened layer off you just created . I used very sharp
M35/M42 in a lantern toolpost on an old Logan . Finishes beautifully ...
--
Snag
"90 FLHTCU "Strider"
'39 WLDD "PopCycle"
BS 132/SENS/DOF
Jim Wilkins
> ...
> There is a good chance that the shaft is ordinary mild steel, as Delta
> was making these by the million for small dollars. If mild steel, a
> leaded steel (like 12L14) would work dandy.
>
> Touch the old shaft to a grinder and look at the sparks. This will tell
> you if the shaft is alloy steel.
>
> Joe Gwinn
The original shaft from my 10" Delta files and sparks like mild steel,
and the pulley setscrew dug deeply into it. The end shows that it was
cut to length with a bandsaw.
You could make it from solid drill rod the size of the bearings and
sleeve the pulley bore on the large end. I found out the hard way that
drill rod needs annealing after a TIG weld.
jsw
Ed Huntress
"Snag" <snag...@comcast.net> wrote in message
news:n_9%m.1721$Sk4...@newsfe10.iad...
Yup, that's been my experience with it, too. I use it because I happen to
have a couple of bars of normalized 4140 that were given to me, and I've
used it for a number of little shaft jobs, turning it with what is probably
M2 -- my ancient stash of Crucible Rex (no number) -- on a 64-year-old South
Bend 10L, with a rocker (lantern) toolpost. It cuts nicely.
I've also machined pre-hardened 4140, but that was on an old Reed-Prentice
lathe with carbide cutters. My SB and I don't do very well on steel harder
than Rc 40 or so. I've managed it a couple of times, but not reliably.
Anyway, that's a pretty strong steel, and it makes a good high-end solution.
Others have recommended Stressproof, which is extra-hard-drawn 1144 with a
stress relief heat treatment. It has about the same yield (around 100 kips)
as normalized 4140 but only about half the elongation. Better elongation is
the primary advantage of 4000 Series over other carbon steels, but it
shouldn't make any difference in this application, because if it takes a
permanent bend, you're screwed anyway. <g>
I'd use whichever of the two is more readily available.
--
Ed Huntress
Joseph Gwinn
<8886c4e0-9a4a-4348...@k17g2000yqh.googlegroups.com>,
Jim Wilkins <kb1...@gmail.com> wrote:
> On Dec 31, 5:49�pm, Joseph Gwinn <joegw...@comcast.net> wrote:
> > ...
> > There is a good chance that the shaft is ordinary mild steel, as Delta
> > was making these by the million for small dollars. �If mild steel, a
> > leaded steel (like 12L14) would work dandy. �
> >
> > Touch the old shaft to a grinder and look at the sparks. �This will tell
> > you if the shaft is alloy steel.
> >
> > Joe Gwinn
>
> The original shaft from my 10" Delta files and sparks like mild steel,
> and the pulley setscrew dug deeply into it. The end shows that it was
> cut to length with a bandsaw.
Bingo. I suspected as much. It's cheaper for Delta to make this part
big enough that ordinary steel is good enough, so that's what they did.
> You could make it from solid drill rod the size of the bearings and
> sleeve the pulley bore on the large end. I found out the hard way that
> drill rod needs annealing after a TIG weld.
There are lots of alloys used to make drill rod, and some are air
hardening.
I would just make the new axle from 12L14 (which is a bit stronger than
ordinary mild steel like 1018), and put the money and effort into good
bearings and accurate fitting to the shaft, so no repeat drama.
Joe Gwinn
Snag
>> speeds , light cuts , and normal feed rates . Dwell in one spot too
>> long and you'll be grinding the hardened layer off you just created
>> . I used very sharp M35/M42 in a lantern toolpost on an old Logan .
>> Finishes beautifully ...
>>
>> --
>> Snag
>
> Yup, that's been my experience with it, too. I use it because I
> happen to have a couple of bars of normalized 4140 that were given to
> me, and I've used it for a number of little shaft jobs, turning it
> with what is probably M2 -- my ancient stash of Crucible Rex (no
> number) -- on a 64-year-old South Bend 10L, with a rocker (lantern)
> Ed Huntress
Cabinet shop I useta work at got a new CNC router (4'X12' bed) . I ended
up with three pieces of (pretty sure) 4140 that were 2 3/8 to 3 1/4 dia and
6 ft long ... They were part of the shipping bracing ... this stuff throws a
spark identical to known 4140 , and hardens exactly like it . I've used
about 2 feet ...also got some 3/8" plate brackets an' stuff , same material
.
And about 20 feet of 1 1/4 rebar ... hey , ya gonna throw that old chunk
of metal away ? Well , throw it MY way !
Wes
>Yup, that's been my experience with it, too. I use it because I happen to
>have a couple of bars of normalized 4140 that were given to me, and I've
>used it for a number of little shaft jobs, turning it with what is probably
>M2 -- my ancient stash of Crucible Rex (no number) -- on a 64-year-old South
>Bend 10L, with a rocker (lantern) toolpost. It cuts nicely.
Is 41L40 much different that 4140? Reason I asked, is I ordered a piece of that to make
something and got impatient when I saw it wasn't going to make it to me until 1/4/2010. I
really hate turning 1.25" dia stock into 9/16" dia stock but I didn't feel like waiting.
12L14 is a joy btw.
Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller
Ed Huntress
"Wes" <clu...@lycos.com> wrote in message
news:y7b%m.292775$mn3....@en-nntp-03.dc1.easynews.com...
> "Ed Huntress" <hunt...@optonline.net> wrote:
>
>>Yup, that's been my experience with it, too. I use it because I happen to
>>have a couple of bars of normalized 4140 that were given to me, and I've
>>used it for a number of little shaft jobs, turning it with what is
>>probably
>>M2 -- my ancient stash of Crucible Rex (no number) -- on a 64-year-old
>>South
>>Bend 10L, with a rocker (lantern) toolpost. It cuts nicely.
>
>
> Is 41L40 much different that 4140? Reason I asked, is I ordered a piece
> of that to make
> something and got impatient when I saw it wasn't going to make it to me
> until 1/4/2010. I
> really hate turning 1.25" dia stock into 9/16" dia stock but I didn't feel
> like waiting.
> 12L14 is a joy btw.
>
> Wes
'Don't know about it, Wes, and I've never machined it. If it's as
advertised, it must be something like 12L14 is to 1214.
If you try it, please let us know how it is.
--
Ed Huntress
Jim Wilkins
> ...
> I would just make the new axle from 12L14 (which is a bit stronger than
> ordinary mild steel like 1018), and put the money and effort into good
> bearings and accurate fitting to the shaft, so no repeat drama.
>
> Joe Gwinn
I forgot to mention that part. Oilite bronze bushings compress when
pressed in and probably will have to be reamed to fit. IIRC I pulled
the reamer through, with centering shims (tape?) around the shank, so
the two holes would line up.
Reamers don't always cut well backwards. The 5/8" one I used had been
ground on the shank with a round-edged wheel that left enough of an
angle on the back end of the flutes to self-center. I have others that
are almost square there and make a mess backwards.
jsw
Wes
>'Don't know about it, Wes, and I've never machined it. If it's as
>advertised, it must be something like 12L14 is to 1214.
>
>If you try it, please let us know how it is.
I'll thread another tool post stud for grins after I get it. Will post a followup.
andy
(stress proof) 1.25" diameter. 1" would have been nicer, but I assume
tolerance= -0.006 means the piece is smaller than what I need. I
checked out all the other steels recommended and "fair machinability"
scares me. This shaft has three diameters, and is threaded in two
spots. Did I mention that i am a wood guy? I really like this saw
however, and will give it my best shot to get it running again.
I took the old shaft to the grinder, and the sparks were more
"fireworky" than a piece of steel pipe. I assume this means it is an
alloy steel of some type. A file cuts into it easily, so it is not
hardened.
Luckilly there was not a lot of drama when the shaft broke. The blade
fell off the machine while cutting, and when I tried to re-mount it,
the upper wheel broke free.
I will take some photos and post my replacement shaft.
Thanks and happy new year!
Andy
Ed Huntress
The 4140 is a useful material to have around, and it's especially good for
transportation machines, like your motorcycles. The extra elongation makes
it safer in applications where it might be loaded to failure, as in a crash.
You can get equal strength in plain carbon steels but not the elongation,
which is another way of saying it has good ductility.
Even though it has only 40 points of carbon, it will harden and strengthen
as if it had a lot more. That's the result of the chromium in the alloy.
--
Ed Huntress
Joseph Gwinn
<3ee2bfa1-b751-4085...@m16g2000yqc.googlegroups.com>,
Jim Wilkins <kb1...@gmail.com> wrote:
> On Dec 31, 6:43�pm, Joseph Gwinn <joegw...@comcast.net> wrote:
> > ...
>
> > I would just make the new axle from 12L14 (which is a bit stronger than
> > ordinary mild steel like 1018), and put the money and effort into good
> > bearings and accurate fitting to the shaft, so no repeat drama.
> >
> > Joe Gwinn
>
> I forgot to mention that part. Oilite bronze bushings compress when
> pressed in and probably will have to be reamed to fit. IIRC I pulled
> the reamer through, with centering shims (tape?) around the shank, so
> the two holes would line up.
I don't visualize what you need to do. Nor did I realize that the
bearing is oilite. Or was it solid bronze or babbit metal? These are
stronger than oilite.
> Reamers don't always cut well backwards. The 5/8" one I used had been
> ground on the shank with a round-edged wheel that left enough of an
> angle on the back end of the flutes to self-center. I have others that
> are almost square there and make a mess backwards.
I would think one would be using a hand reamer. The adjustable ones
would allow one to creep up on the dimension. I recall from old books
that people used a reamer with a long shaft at one end and a T-handle at
the other, plus a bushing that went into the other bearing and accepted
the long shaft, ensuring that the two bearings were lined up correctly
after reaming to size.
While I have not seen such a reamer in present-day catalogs, I haven't
looked either.
Joe Gwinn
Ed Huntress
> Thanks all for the responses. Quick too! I ordered up a piece of 1144
> (stress proof) 1.25" diameter.
Ok, if it's Stressproof(tm), and not just normalized 1144. Stressproof has a
yield strength of around 100 kips (thousands of pounds per square inch).
Ordinary normalized 1144 yields at 58 kips.
That probably will do the job, but if it isn't Stressproof, it's not what
you may think you're ordering.
> 1" would have been nicer, but I assume
> tolerance= -0.006 means the piece is smaller than what I need. I
> checked out all the other steels recommended and "fair machinability"
> scares me. This shaft has three diameters, and is threaded in two
> spots. Did I mention that i am a wood guy? I really like this saw
> however, and will give it my best shot to get it running again.
>
> I took the old shaft to the grinder, and the sparks were more
> "fireworky" than a piece of steel pipe. I assume this means it is an
> alloy steel of some type. A file cuts into it easily, so it is not
> hardened.
More sparks generally mean more carbon. Alloys, in general, make fatter,
less-sharp sparks.
Although some folks here will disagree, my guess, based on some materials
experience, is that the original is a piece of cold-rolled, medium carbon
steel. The most likely grade is 1040. That's a very common steel for
mass-produced parts that have to withstand a medium load. It's probably the
most common steel used for machinery parts, and it's even used for things
that we think are very demanding, like the shafts on McPherson struts.
As a rule I go upscale from what I think the original is, if I'm machining a
replacement part for something. 1020 may do the job but I'm not going to
machine a part twice to find out, when I could have used stronger steel and
done the job once.
>
> Luckilly there was not a lot of drama when the shaft broke. The blade
> fell off the machine while cutting, and when I tried to re-mount it,
> the upper wheel broke free.
>
> I will take some photos and post my replacement shaft.
>
> Thanks and happy new year!
>
> Andy
Happy New Year to you, too, Andy. And good luck making the part!
--
Ed Huntress
Jim Wilkins
> Jim Wilkins <kb1...@gmail.com> wrote:
> ...
> I would think one would be using a hand reamer. The adjustable ones
> would allow one to creep up on the dimension. I recall from old books
> that people used a reamer with a long shaft at one end and a T-handle at
> the other, plus a bushing that went into the other bearing and accepted
> the long shaft, ensuring that the two bearings were lined up correctly
> after reaming to size.
>
> While I have not seen such a reamer in present-day catalogs, I haven't
> looked either.
>
> Joe Gwinn
This is a machine reamer with a setscrew flat on the shank. I turned
it by hand with a Crescent wrench. It was second hand and may have
been modified to go on a turret lathe. It wasn't meant for the use you
described but it worked.
The shaft could be turned to fit after reaming, or even turned small
to the unreamed size. It's much easier to fine tune the shaft diameter
with a lathe than the hole size with a reamer. I assume the bandsaw
has pressed-in bronze bushings like mine since the shaft looked
similar.
jsw
Joseph Gwinn
<f9dd037c-3fe4-4d2b...@u41g2000yqe.googlegroups.com>,
Jim Wilkins <kb1...@gmail.com> wrote:
> On Dec 31, 9:12�pm, Joseph Gwinn <joegw...@comcast.net> wrote:
> > �Jim Wilkins <kb1...@gmail.com> wrote:
> > ...
> > I would think one would be using a hand reamer. �The adjustable ones
> > would allow one to creep up on the dimension. �I recall from old books
> > that people used a reamer with a long shaft at one end and a T-handle at
> > the other, plus a bushing that went into the other bearing and accepted
> > the long shaft, ensuring that the two bearings were lined up correctly
> > after reaming to size.
> >
> > While I have not seen such a reamer in present-day catalogs, I haven't
> > looked either.
> >
> > Joe Gwinn
>
> This is a machine reamer with a setscrew flat on the shank. I turned
> it by hand with a Crescent wrench. It was second hand and may have
> been modified to go on a turret lathe. It wasn't meant for the use you
> described but it worked.
If I picture this, you used the long straight shank of the reamer (plus
a bushing?) as the pilot shaft in the other bearing to ensure that
bearing being reamed lines up with pilot-shaft bearing?
> The shaft could be turned to fit after reaming, or even turned small
> to the unreamed size. It's much easier to fine tune the shaft diameter
> with a lathe than the hole size with a reamer. I assume the bandsaw
> has pressed-in bronze bushings like mine since the shaft looked
> similar.
That was the implication, and the pictures of the upper axle tend to
support this. Too old to be built with ball bearings.
Joe Gwinn
Ned Simmons
<joeg...@comcast.net> wrote:
>
>That was the implication, and the pictures of the upper axle tend to
>support this. Too old to be built with ball bearings.
The ball bearings and locknuts are shown in the first photo, but the
appearance of the bearing housing does suggest that the saw was
originally designed with babbitt or bronze bearings. I had a 36"
Crescent saw that I bought at an auction of a furniture factory in VT
in 1980 or so. I was surprised when I removed the wheels to move the
saw that it had needle bearings where I expected to find babbitt, so I
don't think it was unusual for a mfr to make this sort of change while
continuing to reuse the old castings.
This is the same Crescent saw that I had, but it's old enough that it
has babbitt bearings.
http://wiki.owwm.com/Default.aspx?Page=CrescentBandSawRestoration1&AspxAutoDetectCookieSupport=1
--
Ned Simmons
Jim Wilkins
> Jim Wilkins <kb1...@gmail.com> wrote:
>...
> a bushing?) as the pilot shaft in the other bearing to ensure that
> bearing being reamed lines up with pilot-shaft bearing?
> Joe Gwinn
Yes. I fixed the bandsaw about 20 years ago and don't remember it as
well as the brass bearings on my front end loader, so I may be mixing
the two jobs.
The 'bushing' on the reamer shank was probably a thick layer of
aluminum auto body tape.
Some reamers work better than others backwards. They are ground with a
bevel on the normal leading end and may have a short, imperceptible
taper on the cutting edges. Without these they can chatter or not cut
concentric with the drilled hole. I have a tool and cutter grinding
setup that can bevel them to cut backwards. Presumably few others do
and I don't know a good way to grind a reamer by hand. Lautard(?)
mentioned a honing fixture for them but it doesn't control diameter.
You can make a D bit that serves as a reamer with simple equipment,
possibly only a bench grinder. If you make it on the end of drill rod
you can use the rod as the pilot. I think you would have to press in
only one bearing first and bush the drill rod to the other opening.
After reaming the first bearing you could use it to guide the rod for
reaming the second.
I'm using my HDTV as the laptop's display since it shows two full .pdf
pages at once. It's fine for reading (a download of Holtzapffel
book1), sort of awkward for typing because it's so far out of line
with the keyboard. Sorry for any missed typos.
jsw
Joseph Gwinn
Ned Simmons <ne...@nedsim.com> wrote:
Very interesting webpage. I assume that the "Georgia Agrirama" is a
museum.
Joe Gwinn
john
41L40 has lead in it to make machining easier. It is not recommended to
weld because of the lead. 4140 can be easy or hard to cut depending on
the sulfur content. I think the max allowable sulfur is .2% The more
sulfur the harder it is to weld it, but the easier it is to machine it.
If you get a piece with no sulfur in it machining will be miserable.
John
john
sparks were more numerous than the steel pipe but of the same general
color and shape, you probably had a shaft of 1045 steel. Alloy steel
usually sparks less than mild steel. Try grinding the end of an old
file and see the sparks. The file is usually 1090 steel, the xx90
indicating 90 points of carbon.
John
Ed Huntress
"john" <amd...@intergrafix.net> wrote in message
news:9Oednafvo7PGkubW...@giganews.com...
Huh. It's interesting that a strict alloy like 4140 would allow enough
difference in sulfur to have much effect on machineability. It's not
something I have a lot of experience with, and most that I've turned
probably all came from the same batch.
--
Ed Huntress
Wes
I think I'm going to turn it into bolts for my RGG gatling gun. I turned some 1144 today
at work. That was pretty nice to work with.
Not sure how this thread got brought back to life.
Ed Huntress
Now, what in the HELL are you going to do with a Gatling gun? Are you doing
Civil War re-enactments, or are you joining the Michigan Militia? <g>
>
> Not sure how this thread got brought back to life.
Somebody just checks in every once in a while, probably.
--
Ed Huntress
John
I learned about the sulfur from hard experience. I was running a job
making pins from 4140 and the job was going good. I would make about 500
at a run. Well one run was giving me a lot of grief. busting inserts,
not holding size, and a bunch of other problems. I tested the hardness
and checked the certs. I had the metal assayed and it agreed with the
certs papers. The only thing different in this batch of material was
that it had absolutely no sulfur content in it. ( it came from Romania)
I guess the sulfur gives the necessary lubrication to make cutting it
easy.
John
Ed Huntress
"John" <amd...@intergrafix.net> wrote in message
news:RpWdnQQRtv2g2ebW...@giganews.com...
Yes, and it doesn't take much sulfur. There are two ways to introduce it
into a steel alloy, and one method, called "microalloying," produces a big
gain in machineability with small amounts of sulfur. But it doesn't just
happen by dumping in some sulfur. I don't remember what the microalloying is
all about, but it requires a specific process.
Lead and bismuth are other elements added to improve machineability. And
some screw-machine stock, made for applications where lead and sulfur can't
be tolerated, gets a machineability boost from the addition of calcium. In
the late '70s, calcium-containing alloys became popular for making a lot of
automobile parts.
--
Ed Huntress
John
It was me not paying attention to the dates of the last post. The
bandsaw axle sort of got my attention. I bought a DoAll model C-80 out
of the scrap yard for 400 bucks a while ago and had to make new spindles
for it. The bearings had spun on the axles and they had to be replaced
as well as the bearings. The metal I used was from some of the scrap
of the pins I made of the 4140. I still have a barrel full of the out
of tol. pins accumulated over the years. I just used another piece today
to make up a lathe chuck wrench. By the way to get a good finish on the
metal you have to take at least ten thou. per side and turn at least 300
ft/min.
John
John
Ed Huntress
Is that the 4140 without sulfur? It's been so long since I've turned that
alloy that I can hardly remember it.
--
Ed Huntress
DoN. Nichols
>
> "john" <amd...@intergrafix.net> wrote in message
> news:9Oednafvo7PGkubW...@giganews.com...
[ ... ]
>> 41L40 has lead in it to make machining easier. It is not recommended to
>> weld because of the lead. 4140 can be easy or hard to cut depending on
>> the sulfur content. I think the max allowable sulfur is .2% The more
>> sulfur the harder it is to weld it, but the easier it is to machine it. If
>> you get a piece with no sulfur in it machining will be miserable.
>>
>> John
>
> Huh. It's interesting that a strict alloy like 4140 would allow enough
> difference in sulfur to have much effect on machineability. It's not
> something I have a lot of experience with, and most that I've turned
> probably all came from the same batch.
According to my copy of the Jorgensen steels catalog:
steel In Percent
------------------------------
4140 C 0.38/0.43
Mn 0.75/1.00
P 0.035 Max
S 0.040 Max
Si 0.20/0.35
Cr 0.80/1.10
Mo 0.15/0.25
With the following note:
The analyses of the leaded grades are the same as above with the
addition 0f 0.15/0.35 Lead (Pb)
For welding they say in part:
"Difficult to weld, but can be welded by any of the common
welding processeds providing section is preheated, and stress
relieved after welding."
along with some other comments.
Machinability (for 41L42) is about 75% of 1212, and 66% for
4142. Approximately 130 SFM for the 41L42.
Personally, assuming that the bandsaw axle runs in ball
bearings, I would use whatever steel you can easily machine. No need to
go for 4140 for that.
Enjoy,
DoN.
--
Email: <dnic...@d-and-d.com> | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---
John
>>
>> It was me not paying attention to the dates of the last post. The bandsaw
>> axle sort of got my attention. I bought a DoAll model C-80 out of the
>> scrap yard for 400 bucks a while ago and had to make new spindles for it.
>> The bearings had spun on the axles and they had to be replaced as well as
>> the bearings. The metal I used was from some of the scrap of the pins I
>> made of the 4140. I still have a barrel full of the out of tol. pins
>> accumulated over the years. I just used another piece today to make up a
>> lathe chuck wrench. By the way to get a good finish on the metal you have
>> to take at least ten thou. per side and turn at least 300 ft/min.
>>
>>
>> John
>
> Is that the 4140 without sulfur? It's been so long since I've turned that
> alloy that I can hardly remember it.
>
I switched suppliers after that bad batch and had no more problems with
cutting the metal. We had to supply certifications so I kept an eye on
the sulfur content and made sure it was always on the high end of the
limits. It ran on the high end of the permitted amounts, I only machined
it and didn't weld on it. I think the percentage ran about .18 At that
percentage it would run well at those speeds. The part we ran required
holding +/- .0005 in. on 6 inch turn and once the machine stabilized it
ran all day with almost no scrap. The only problem was the air chuck
would sometimes not hold the piece properly and it would slip if we had
the feed or rpm running too high. I made thousands of those parts.
Ed Huntress
Machining a lot of metal in batch- or continuous production really gives one
a feel for subtleties that we don't usually pick up in ordinary hobby
machining. If you made thousands, you must really know the material.
Note what Don reported about the standard for sulfur content in 4140 --
0.040% maximum. Another thing that shows up is slight "modifications" to
standard alloy specifications, sometimes done for a good reason. You may
have run into one of those circumstances. I've heard of 4000-series alloys
that contained more chromium and less carbon than the specs require, for the
purpose of meeting the elongation specification, which apparently is not
easy.
But, like most technical things about materials, I haven't spoken to
metallurgical engineers for decades. It used to be a major part of my job.
--
Ed Huntress
Wes
>> I think I'm going to turn it into bolts for my RGG gatling gun. I turned
>> some 1144 today
>> at work. That was pretty nice to work with.
>
>Now, what in the HELL are you going to do with a Gatling gun? Are you doing
>Civil War re-enactments, or are you joining the Michigan Militia? <g>
It is only a .22 . Maybe mount motors and a search/acquisition radar and it could be a
Phalanx Close-In Weapons System (CIWS) for Michigan Mosquitoes. Caliber might be a bit
small though. ;)
Wes
Ed Huntress
I'll bet you're going to be hell on rabbits. They'll be pre-tenderized. <g>
--
Ed Huntress
Wes
>I'll bet you're going to be hell on rabbits. They'll be pre-tenderized. <g>
The sad thing is, rabbits are not very plentiful where I live. We have too many coyotes
now. I wish I had the patience for hunting coyote.
Wes