welding C45 (1045) steel ; how to TIG ?

[p***@hotmail.com]

(did a quick google on the subject but found little so I ask here)

For a project I need to weld a C45 (1045 steel, 0.45% carbon) on a C45
shaft; see picture below:

http://www.anotherpower.com/gallery/dinges/rotor_C45_and_shaft_2

(the large part will have a hole in it and be shoved over the shaft. I
intend to fix with either Loctite 638 or epoxy (West Systems/Gougeon
Brothers). According to my calculations I should have plenty of safety
rating (9x), but I wonder whether a weld wouldn't be better/easier.

Being C45 it contains more than 0.3% carbon and is thus hard to weld.
Could anyone tell me the proper procedure ? Preferably TIG as that is
my preferred process.

I assume a pre-heat will be necessary ? To what temperature ? What
filler ? What are the 'snags' to keep in mind when welding ? Or should
I just forget about welding it ?

Looking for any advice from those who have actually experience welding
this kind of material.

Regards,

Peter Dingemans.

[Ernie Leimkuhler]

Post by p***@hotmail.com
(did a quick google on the subject but found little so I ask here)
For a project I need to weld a C45 (1045 steel, 0.45% carbon) on a C45
http://www.anotherpower.com/gallery/dinges/rotor_C45_and_shaft_2
(the large part will have a hole in it and be shoved over the shaft. I
intend to fix with either Loctite 638 or epoxy (West Systems/Gougeon
Brothers). According to my calculations I should have plenty of safety
rating (9x), but I wonder whether a weld wouldn't be better/easier.
Being C45 it contains more than 0.3% carbon and is thus hard to weld.
Could anyone tell me the proper procedure ? Preferably TIG as that is
my preferred process.
I assume a pre-heat will be necessary ? To what temperature ? What
filler ? What are the 'snags' to keep in mind when welding ? Or should
I just forget about welding it ?
Looking for any advice from those who have actually experience welding
this kind of material.
Regards,
Peter Dingemans.

Welding is possible, but you will have to be very careful to avoid
warping the shaft.

Preheat would be around 600degF on both parts.
TIG filler would be ER80S-D2.

You can buy the TIG filler at Tigdepot.

http://www.tigdepot.net/products2.php?categoryID=38


It would be best if you could get the whole assembly rotating while you
weld.

After welding, bury the whole thing in powdered lime, or wrap up in rock
wool insulation and a welding blanket.
Powdered lime works better and is dirt cheap.
The idea is to have it cool down very slowly.

I am surprised you aren't doing an interference fit.
Machine the 2 parts so you have a hole about 0.002" - 0.004" too small
for the shaft, then heat the piece with the hole and freeze the shaft.
Assemble and then let them reach room temp together.

[b***@gmail.com]

Post by p***@hotmail.com
(did a quick google on the subject but found little so I ask here)
For a project I need to weld a C45 (1045 steel, 0.45% carbon) on a C45
http://www.anotherpower.com/gallery/dinges/rotor_C45_and_shaft_2
(the large part will have a hole in it and be shoved over the shaft. I
intend to fix with either Loctite 638 or epoxy (West Systems/Gougeon
Brothers). According to my calculations I should have plenty of safety
rating (9x), but I wonder whether a weld wouldn't be better/easier.
Being C45 it contains more than 0.3% carbon and is thus hard to weld.
Could anyone tell me the proper procedure ? Preferably TIG as that is
my preferred process.
I assume a pre-heat will be necessary ? To what temperature ? What
filler ? What are the 'snags' to keep in mind when welding ? Or should
I just forget about welding it ?
Looking for any advice from those who have actually experience welding
this kind of material.
Regards,
Peter D

I'm not going to solve your welding problems but if, as it appears,
the smaller diameter shaft goes completely through the larger diameter
drum and they have been machined to size, as it appears, I believe it
might be better if you cut a keyway in the cylinder and key seats in
the shaft and then glue or set screws to tighten things up. I say this
because, if they are to finished size and you attempt to weld the
shaft into the drum there is a very good chance that some warpage will
occur which, if the parts are already to size you will be unable to
correct accurately.

I am assuming that this is probably a wind generator and may be
rotating at fairly high speeds.






Bruce in Bangkok
(brucepaigeATgmailDOTcom)

[p***@hotmail.com]

Thanks Ernie and Bruce.

I had considered doing a thermal crimp too (interference fit), but my
machining abilities are not up to standard for that. I agree it would
be the best solution. The epoxy should work too, in this case, where
only 0.6% of its rated strength is actually needed.

Was thinking about using epoxy and perhaps add a weld. However,
considering the strength of the epoxy, the hard-to-weld
characteristics of C45, pre-heating needed, slow cooling and possible
warping of the shaft, I think I won't weld.

Bruce, this particulator motorconversion (generator) will be used on a
diesel motor, as a genset, but the next one (possibly a 5-7.5 kW) is
going to fly.

Thanks for your replies. I hadn't noticed what happened to this group
till after I posted my question. What a shame. I've been reading it
for a few years now, on and off. Last time I did was a few months ago.
A shame to see a group like this with a few good contributors go down
the drain.

Things have changed since I first got on Usenet in 1996...

[b***@gmail.com]

Post by p***@hotmail.com
Thanks Ernie and Bruce.
Bruce, this particulator motorconversion (generator) will be used on a
diesel motor, as a genset, but the next one (possibly a 5-7.5 kW) is
going to fly.

From your description it appears that you are building something
similar to the permanent magnet motors, only in reverse. What is the
advantage to this other then size? It would seem to me that without
control of the variable magnetism in the rotor output will be directly
proportional to rotational speed. Or do I have it wrong?

I am interested as I spend a lot of my time on a boat and a small,
light, high output gen-set would be a great idea.

Someone is trying out some sort of attack on the site. If your
newsgroup reader has the filters just run the filter on "message not
available" after the downloading is complete. That seems to work for
me.



Bruce in Bangkok
(brucepaigeATgmailDOTcom)