If you were in my shoes.. what would you do?
A shaft is needed for a machine, 1.5" dia, but with a collar at the
middle of it. The collar needs to be about 3" od and about 1/2" thick.
Access to machining equipment is limited. No mill, and an abused lathe
that is too old with only basic basic tooling. Budget being the eternal
issue, I am planning on machining the collar out of mild steel and
carefully TIG welding it into the shaft, and then re turning it to cut
away excess weld and to make sure it's not crooked as hell. Has anyone
tried this and failed because the shaft warped excessively? suggestions
please...

I would attempt to machine the shaft from larger stock, except it would
be a first lesson on super close tolerances on the 1.5" as well as the
nice finish. overall length of shaft is perhaps 12".

Thanks for the advice
- Loren

On 28 Nov 2005 20:23:43 -0800, "Loren"
wrote:

If you were in my shoes.. what would you do?
A shaft is needed for a machine, 1.5" dia, but with a collar at the
middle of it. The collar needs to be about 3" od and about 1/2" thick.
Access to machining equipment is limited. No mill, and an abused lathe
that is too old with only basic basic tooling. Budget being the eternal
issue, I am planning on machining the collar out of mild steel and
carefully TIG welding it into the shaft, and then re turning it to cut
away excess weld and to make sure it's not crooked as hell. Has anyone
tried this and failed because the shaft warped excessively? suggestions
please...

I would attempt to machine the shaft from larger stock, except it would
be a first lesson on super close tolerances on the 1.5" as well as the
nice finish. overall length of shaft is perhaps 12".

Thanks for the advice
- Loren

Perhaps you could have the proper thing machined by someone here? Id
be happy to do it as a project, if you have a decent print to work
from. Gratis, but you pay the shipping.

Depending on the loading..you could also make it a split coupler.

Gunner, California

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

A decent print I could do! Hell, I'll give it to you in Solidworks if
you desire. I appreciate the offer Gunner, thank you. How would you
feel about a short section of NF thread at the ends, stepped down to
whatever dia.. 3/4" 7/8" or 1".. would be fine. And of course two
keyways to complicate things. oh yeah, all this times 3. sigh...
yeah.. it's for a powered tubing roller and these are for the drive
shafts.

I'll go ahead with a test piece I think and by this weekend my choices
will be more clear.

Has anyone had success with a shaft weldment as an alternative to
machining from stock?

Thanks guys.
- Loren

I did something like this with a shaft that someone had put some
brazing on.

It was only 5/8" and looked a bit like a sausage.

Had to grind the two spots where the bearings were to go.

When I was done, it still looked like a sausage, but the bearings were
concentric. :-)


I don't think 1-1/2" should warp (much). Especially if you don't
put too much heat into it.

Maybe spot weld around then...

The usual approach. Try it and see.

DOC

"
....


I'll go ahead with a test piece I think and by this weekend my choices
will be more clear.

Has anyone had success with a shaft weldment as an alternative to
machining from stock?

Thanks guys.
- Loren

On 28 Nov 2005 22:52:09 -0800, "Loren"
wrote:

A decent print I could do! Hell, I'll give it to you in Solidworks if
you desire. I appreciate the offer Gunner, thank you. How would you
feel about a short section of NF thread at the ends, stepped down to
whatever dia.. 3/4" 7/8" or 1".. would be fine. And of course two
keyways to complicate things. oh yeah, all this times 3. sigh...
yeah.. it's for a powered tubing roller and these are for the drive
shafts.


Send it in any common format. Shrug..Ive got most of the tools to
decode it.

I'll go ahead with a test piece I think and by this weekend my choices
will be more clear.

Has anyone had success with a shaft weldment as an alternative to
machining from stock?

Thanks guys.
- Loren

Ive welded shafts up to length before..motor shafts up to
drivelines..and never did get them truely square, even when fixturing
in V blocks. I always got some warpage at the weldment that required
either bending/straightening to get it to run moderately true. Which
means it really depends on what speed you are going to turn it.

Ive got the HLV-H, so can do about 9x16 or so between centers. The
15x52 Clausing spit out an $80 drive belt..so its down at the moment,
until I can figure out how so scrounge up a cheap/free one.

Id be happy to do your project for you. I enjoy doing projects.

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

Loren wrote:
If you were in my shoes.. what would you do?
A shaft is needed for a machine, 1.5" dia, but with a collar at the
middle of it. ...
Thanks for the advice
- Loren

I'd look real hard at a separate collar clamped or pinned to the shaft.
If you use a taper pin it can be retightened if it works loose.

Most of the shafts on my South Bend lathe are assembled with taper
pins.

jw

Make your collar a good fit. Bevel the hole for about 1/16th at 45 degrees
approximately. Braze with a silver alloy.
The advantage of silver soldering or silver brazing is that the joint
will be very strong, temperature distortion is minimal, and you will not
need to machine off excess if you are careful. With TIg you will be putting
too much heat into the shaft risking bending.
The shaft and collar clearance can be as much as .005 I would try for
around .003 plus to allow the silver alloy to suck in. Set the shaft
vertical with a pipe sleeve on the outside to support the collar in the
correct position. Apply flux paste to the shaft and collar hole before
assembling.

Randy

"Loren" wrote in message
oups.com...
If you were in my shoes.. what would you do?
A shaft is needed for a machine, 1.5" dia, but with a collar at the
middle of it. The collar needs to be about 3" od and about 1/2" thick.
Access to machining equipment is limited. No mill, and an abused lathe
that is too old with only basic basic tooling. Budget being the eternal
issue, I am planning on machining the collar out of mild steel and
carefully TIG welding it into the shaft, and then re turning it to cut
away excess weld and to make sure it's not crooked as hell. Has anyone
tried this and failed because the shaft warped excessively? suggestions
please...

I would attempt to machine the shaft from larger stock, except it would
be a first lesson on super close tolerances on the 1.5" as well as the
nice finish. overall length of shaft is perhaps 12".

Thanks for the advice
- Loren

In article 1133238223.945886.118090
@o13g2000cwo.googlegroups.com,
says...
If you were in my shoes.. what would you do?
A shaft is needed for a machine, 1.5" dia, but with a collar at the
middle of it. The collar needs to be about 3" od and about 1/2" thick.
Access to machining equipment is limited. No mill, and an abused lathe
that is too old with only basic basic tooling. Budget being the eternal
issue, I am planning on machining the collar out of mild steel and
carefully TIG welding it into the shaft, and then re turning it to cut
away excess weld and to make sure it's not crooked as hell. Has anyone
tried this and failed because the shaft warped excessively? suggestions
please...

I would attempt to machine the shaft from larger stock, except it would
be a first lesson on super close tolerances on the 1.5" as well as the
nice finish. overall length of shaft is perhaps 12".


I'd use a clamp collar...
http://www.staffordmfg.com/

or one of these...
http://www.meibuhr.com/retainin.htm

The clamp collars are available from McMaster-Carr starting
on p. 1034

http://www.mcmaster.com/

Ned Simmons

Id be happy to do your project for you. I enjoy doing projects.

Gunner



Hey Gunner! I have a near endless supply of projects. Could I get you to do
them for me for free?

On Tue, 29 Nov 2005 14:28:58 GMT, "Dave Lyon"
wrote:



Id be happy to do your project for you. I enjoy doing projects.

Gunner



Hey Gunner! I have a near endless supply of projects. Could I get you to do
them for me for free?


Free is good. Whatcha got to trade?

G

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

According to :
Loren wrote:
If you were in my shoes.. what would you do?
A shaft is needed for a machine, 1.5" dia, but with a collar at the
middle of it. ...
Thanks for the advice
- Loren

I'd look real hard at a separate collar clamped or pinned to the shaft.
If you use a taper pin it can be retightened if it works loose.

And to add to the complexity -- you mentioned keyways in another
branch of the thread. How close do they need to come to the collar?
Given that, I would be tempted to make the shaft with a full-length
keyway, and fit the collar to it with a key to prevent rotation, a
setscrew to hold the key in firmly, and then the taper pin to lock it at
a given point along the shaft.

This way, the keyway can be cut in a single pass with a
horizontal milling cutter -- a lot less trouble than trying to make a
keyway up close to an integral collar.

Good Luck,
DoN.
--
Email: | 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 ---

what are the advantages to a taper pin as opposed to a normal pin, or a
grade 8 bolt? would the pin be behind the collar or through it?

The collar will be the platform for a roll bender die setup and it will
be subjected to a thrust load, so I was considering cutting into the
shaft to make a notch for a heavy duty clamp collar to sit in. so say,
buy a collar for 1.375" or 1.25" shaft and turn that notch into the
1.5" shaft. that baby would never move, right? The shaft could be
ordered with a keyway full length, and I could settle for tapped holes
in the ends rather than stepped down thread. Also, easy to
replace/service if it all crapped out on me..

Thanks guys
- LP

In article 1133335342.174333.5720
@g47g2000cwa.googlegroups.com,
says...
what are the advantages to a taper pin as opposed to a normal pin, or a
grade 8 bolt? would the pin be behind the collar or through it?

It's easier to get a good locational fit since you ream the
pin hole with the collar in place and the taper makes it
easy to produce an interference fit in both parts. Also
easier to assemble and disassemble than a tight fitting
straight pin since it only takes a few taps to seat or
unseat the pin.


The collar will be the platform for a roll bender die setup and it will
be subjected to a thrust load, so I was considering cutting into the
shaft to make a notch for a heavy duty clamp collar to sit in. so say,
buy a collar for 1.375" or 1.25" shaft and turn that notch into the
1.5" shaft. that baby would never move, right?

The collar mfrs publish data on the thrust required to move
the collar...
http://www.staffordmfg.com/pages/engdata_body.htm#5


The shaft could be
ordered with a keyway full length, and I could settle for tapped holes
in the ends rather than stepped down thread. Also, easy to
replace/service if it all crapped out on me..

Definitely easier if you don't require close concentricity
and the threads are somewhat smaller than the shaft. Tap
the ends and screw long alloy hex socket set screws into
the holes til they bottom out.

Ned Simmons

Wow! Thanks for that Ned. So a collar with a mere 5/16" bolt
potentially will hold 3000lbs. This is a medium duty machine so I think
that's good enough. Oh wait, what about knurling the shaft where the
collar is positioned? I would guess that it would definitely improve
the "bite"... right? it's easier than cutting into the shaft.. and in
the end.. it's better for something to give a little instead of snap
and fly I suppose.

ok, Compare a mounted roller bearing and a mounted ball bearing. The
dynamic load capacity is pretty much 2 to 1 in favor of the roller
bearing. Information from mcmaster.

I'm using flange mounted ball bearings and they have a 7200 lbs.
dynamic load capacity. there will be six total working against the same
load and this machine's tension force is by a hand operated screw
leveraged by a sliding 36" or so handle. maybe less. The double set
screw in each bearing is also somewhat needed to keep the shaft from
moving in this situation. BUT... question:

Do you think it would hinder the proper function of the ball bearing if
there were press fit bronze sleeves contacting the shaft where it
passes through the heavy plate that the bearings are attached to?? my
theory is that the bronze bearing will take some of the stress from the
load perpindicular to the shaft which is on the end, between the collar
and threaded end. flawed?

- LP

In article 1133388294.822423.141800
@g47g2000cwa.googlegroups.com,
says...
Wow! Thanks for that Ned. So a collar with a mere 5/16" bolt
potentially will hold 3000lbs. This is a medium duty machine so I think
that's good enough. Oh wait, what about knurling the shaft where the
collar is positioned? I would guess that it would definitely improve
the "bite"... right? it's easier than cutting into the shaft.. and in
the end.. it's better for something to give a little instead of snap
and fly I suppose.

ok, Compare a mounted roller bearing and a mounted ball bearing. The
dynamic load capacity is pretty much 2 to 1 in favor of the roller
bearing. Information from mcmaster.

You should be aware that those ratings are for radial
loads. Mounted ball bearings (flange & pillow blocks, etc)
are generally not recommended for axial (thrust) loads, and
the axial load rating for mounted roller bearings is
substantially less than the radial rating.


I'm using flange mounted ball bearings and they have a 7200 lbs.
dynamic load capacity. there will be six total working against the same
load and this machine's tension force is by a hand operated screw
leveraged by a sliding 36" or so handle. maybe less. The double set
screw in each bearing is also somewhat needed to keep the shaft from
moving in this situation. BUT... question:

How are you sharing the load? It's quite difficult to do
this reliably for bearings on a single shaft.


Do you think it would hinder the proper function of the ball bearing if
there were press fit bronze sleeves contacting the shaft where it
passes through the heavy plate that the bearings are attached to?? my
theory is that the bronze bearing will take some of the stress from the
load perpindicular to the shaft which is on the end, between the collar
and threaded end. flawed?

If I understand, I don't think this will help. Even if you
got the two bearings mounted such that they were load
sharing, which may or may not be possible, the load
carrying capability of a bronze bushing is insignificant
compared to that of a ball or roller bearing.

It would be easier to be helpful if you were to give more
information on what you're trying to accomplish.

Ned Simmons

You should be aware that those ratings are for radial
loads. Mounted ball bearings (flange & pillow blocks, etc)
are generally not recommended for axial (thrust) loads, and
the axial load rating for mounted roller bearings is
substantially less than the radial rating.

Thanks Ned. Yes.. the dynamic load capacity is in reference to a radial
load. I understand the difference.


How are you sharing the load? It's quite difficult to do
this reliably for bearings on a single shaft.

This is a roll bender. it has 3 shafts.. the force from the tension
screw is applied to all 3 shafts thus dividing the load.
The only thrust load will be between the threaded end and the collar as
the material in the roller deforms.


It would be easier to be helpful if you were to give more
information on what you're trying to accomplish.

Ned Simmons

Loren wrote:
snip
. it's for a powered tubing roller and these are for the drive shafts.


so.. the question is.. do you think that combining ball bearings and
bronze bearings will help each other enough to be worth the effort?

I'm only concerned about whether or not the ball bearings will hold up
because I have no convenient method for press fitting a roller bearing.
I have a drill press and a ****ty lathe and its easier to drill and tap
holes to attach flange bearings to a plate.

Also.. will knurling a shaft improve the grab of a collar?

- Loren