On Sunday, November 9, 2014 at 11:17:43 PM UTC+5:30, wrote:
As mentioned in the subject, I'm looking for steel suitable to be used to make an Olympic barbell, 2.2m long and 28mm in diameter. I'm torn between chrome-moly steel and spring steel. Again I'm not a metallurgist and know very little about these things. The bar will be at least 190000 psi tensile strength with 170000 psi yield strength. I'm also looking for decent machining characteristics so that I can put a knurl on it and cut grooves to attach sleeves.

Here are some steels I've thought about

SAE 4340 (Heat treated to the required Tensile strength)
SAE 4140
EN 47??

Thanks


I think we need to buy one branded bar and have to check chemical properties of shaft material..
As we have to do all cnc work or lathe work on Shaft like knurling,turning,grooving before heat treating
But
If we do heat treat bar can bend due to heat then after we need to remove bend on bend remove press machine
or
it take alot of time and money but if we complete this all process ..This bar ll be very easy to make in quantity.

As we know In India EN19 to EN 24 is available but its impossible to heat 7 ft shaft in oven...Oven should be very big.


For more info you can reply me.

On Tue, 30 Mar 2021 21:27:52 -0700 (PDT), Padmanabh Jadhav
wrote:

On Sunday, November 9, 2014 at 11:17:43 PM UTC+5:30, wrote:
As mentioned in the subject, I'm looking for steel suitable to be used to make an Olympic barbell, 2.2m long and 28mm in diameter. I'm torn between chrome-moly steel and spring steel. Again I'm not a metallurgist and know very little about these things. The bar will be at least 190000 psi tensile strength with 170000 psi yield strength. I'm also looking for decent machining characteristics so that I can put a knurl on it and cut grooves to attach sleeves.

Here are some steels I've thought about

SAE 4340 (Heat treated to the required Tensile strength)
SAE 4140
EN 47??

Thanks


I think we need to buy one branded bar and have to check chemical properties of shaft material..
As we have to do all cnc work or lathe work on Shaft like knurling,turning,grooving before heat treating
But
If we do heat treat bar can bend due to heat then after we need to remove bend on bend remove press machine
or
it take alot of time and money but if we complete this all process ..This bar ll be very easy to make in quantity.

As we know In India EN19 to EN 24 is available but its impossible to heat 7 ft shaft in oven...Oven should be very big.


For more info you can reply me.
My knowledge is limited to bars I have purchased at yard sales to be
used as a source of raw material. These bars seem to be made erom the
nastiest material imaginable; the best way to machine them being to
use an angle grinder!

On Thu, 01 Apr 2021 00:04:07 -0400, Gerry
wrote:

On Tue, 30 Mar 2021 21:27:52 -0700 (PDT), Padmanabh Jadhav
wrote:

On Sunday, November 9, 2014 at 11:17:43 PM UTC+5:30, wrote:
As mentioned in the subject, I'm looking for steel suitable to be used to make an Olympic barbell, 2.2m long and 28mm in diameter. I'm torn between chrome-moly steel and spring steel. Again I'm not a metallurgist and know very little about these things. The bar will be at least 190000 psi tensile strength with 170000 psi yield strength. I'm also looking for decent machining characteristics so that I can put a knurl on it and cut grooves to attach sleeves.

Here are some steels I've thought about

SAE 4340 (Heat treated to the required Tensile strength)
SAE 4140
EN 47??

Thanks


I think we need to buy one branded bar and have to check chemical properties of shaft material..
As we have to do all cnc work or lathe work on Shaft like knurling,turning,grooving before heat treating
But
If we do heat treat bar can bend due to heat then after we need to remove bend on bend remove press machine
or
it take alot of time and money but if we complete this all process ..This bar ll be very easy to make in quantity.

As we know In India EN19 to EN 24 is available but its impossible to heat 7 ft shaft in oven...Oven should be very big.


For more info you can reply me.
My knowledge is limited to bars I have purchased at yard sales to be
used as a source of raw material. These bars seem to be made erom the
nastiest material imaginable; the best way to machine them being to
use an angle grinder!

A quick look at the olympic type bars available seem to show an
olympic style bar stated to be "120,000 lbs" tensile strength. If they
actually meant 120,000 lbs/inch square then 4140 (normalized at 810
degrees C) will have a tensile strength of 147,938 psi and 4140
annealed is about 94,000 psi. So 4140 should work.

Companies sell heat treated bar stock
https://www.specialtysteel.com/alloy...-heat-treated/
for example sells 4140 hot rolled with Brinnell of 269/341BHN and a
tensile strength of 156,000 psi. Brinnell Hardness 271 = RC 28.8 and
342 = RC 26.6

--
Cheers,

John B.