Dissimilar Metals

[pockets]

Can cast iron be successfully brazed, silver soldered or? to steel?

[mark rusche]

<font face="Verdana, Arial" size="2">Originally posted by pockets:
Can cast iron be successfully brazed, silver soldered or? to steel?</font>
Yes, you may braze or silver solder cast iron to steel but how about stick welding it (if it is large enough )with a nickel electrode (if you need to machine it ) or Super Gold if you don't need to machine it .There's a good chance it'll work unless it's something like a burned out exhaust manifold or a very poor casting .

[GWRdriver]

I'm very good at silver soldering copper-based metals but I've never had any luck at all getting sound joints with iron and steel. I don't swap solders or fluxes when attempting that but with what I use (Harris Safety-Silv 45 & white flux) I'm not supposed to have to. Still it just never seems to work for me and I avoid it, except for soldering bandsaw blades, and then I seem to have pretty good results.

[pockets]

Okay, gang, here's the scenario: Baldwin WWI gas mechanical trench engine, in 3.75" scale. I want to use high angle mis-alignment ball bearings like you find in pillow blocks. If you have ever seen the socket that the bearing occupies, in the pillow block, you realize that it's a fancy piece of machine work. We're talking a custom form tool and everything.

Plan B: Machine away all of the pillow block, except a .125 wall around the socket, and either braze, solder or shrink it into the journal block.

Comments? What am I missing (be kind)?

[GWRdriver]

Pocket,
I kind of like Plan B . . . except use Loctite. Keep it clean and it won't go anywhere. But it does make me wonder, if you can't get that kind of bearings alone and dispense with cutting away the pillow block.

[pockets]

The bearings are available separately, but they require that fancy socket to function properly.

Hadn't thought about the Loctite. Hmmm...

[mark rusche]

How about a 3or 4 bolt flange block ?

[pockets]

Mark, they are physically too large. This is an outside frame locomotive and there is no way to hide it.

Thanks
Greg

[Fred Rosse]

If you have ever seen the socket that the bearing occupies, in the pillow block, you realize that it's a fancy piece of machine work. We're talking a custom form tool and everything.

Plan B: Machine away all of the pillow block, except a .125 wall around the socket, and either braze, solder or shrink it into the journal block.

Comments? What am I missing (be kind)?[/B][/QUOTE]


If you get a standard spherical roller bearing, you will not have to go through this. This is a standard item, more expensive than ball bearings, but much better, and can take the mis-allignment.

[Unka Jesse]

<font face="Verdana, Arial" size="2">Originally posted by GWRdriver:
Pocket,
I kind of like Plan B . . . except use Loctite. Keep it clean and it won't go anywhere. But it does make me wonder, if you can't get that kind of bearings alone and dispense with cutting away the pillow block.</font>

Harry, Greg, It seems that I have seen bearings like are needed in this application and yet, I don't see how, because there must be a pair of opposing cut-away spots to allow the bearing to be inserted into the special extra outer mounting ring by twisting it in place. Howsomever, I have several bearing catalogs down in my basement library and will dutifully check to see if such a critter does indeed exist.

Harry, I am in complete accord with your idea of using Locktite® to mount that outer sleeve (or whatever you might call it. It must be a slip fit, maybe as much as .001" loose in the bearing housing or else it might not allow entry and/or free movement of the spherical bearing race. Locktite® will not distort the sleeve as would heating for silver solder.

There are "Spherical Roller Bearings" made by Linkbelt® and others, but I doubt that Greg could find one small enough for his purposes. These types actually have barrel shaped rollers running in a sphericaly ground outer race. Capable of extremely heavy loads, but again, probably only made in too large of sizes.

Unka Jesse

[Unka Jesse]

<font face="Verdana, Arial" size="2"> If you get a standard spherical roller bearing, you will not have to go through this. This is a standard item, more expensive than ball bearings, but much better, and can take the mis-allignment.[/B]</font>

Oops, this is the type bearing I describe in my reply to Greg and Harry, but I didn't see that you had already mentioned the possibility of using them. They may not be available in the small size that Greg needs.I shall check to see how small they are available.

Unka Jesse

[Unka Jesse]

Hokay, I just went to my Fafnir® catalogue and the bearings Greg needs are called "External Self-Aligining Bearings" and are available down to 10mm bore size. The 10mm bore has an OD of 33mm with larger sizes having similar size differences. Couldn't locate my spherical roller bearing catalogue.

Pockets, I have a nice picture of the bearing mentioned above I just scanned from the Fafnir catalogue, but I don't lnow how to post it, so will send it to you direct. Any way to post photos here?

Unka Jesse

[This message has been edited by Unka Jesse (edited 10-12-2005).]

[pockets]

Hey, Jesse, glad you found your way over.

I got the picture and replied direct. It looks like what I'm needing. I'll chase down one of those Fafnir books. My Boston Gear bearing catalog wasn't much help, this time.

The picture doesn't show a set screw collar, so I'm guessing that the bearing is a press fit on the axle.

Thanks to all of you guys. I have learned something from each of you.

Regards,
Greg B.

[Unka Jesse]

Greg, I will have to check on the mounting on those bearings, but it may be possible that they use an eccentric locking collar like a lot of Fafnir's RAK series pillow blocks use. Cataloge in basement again, so you gonna have to wait. If it is a press on bearing, then Locktite® would be the way to mount it. There is a thin flowing "wicking" type Locktite that will sneak into a bearlin fit as long as it is not actually a mechanically perfect interstice.

Unka Jesse

[pockets]

Okay, Jesse. Thanks. I don't know how you can stand up straight....You're always bending over backwards to help people.

Best regards,
Greg B.

[fred v]

Pockets, i'm using conveyor take up bearings for my drivers and lead trucks. they already have a 1/2" groove to fit the pedistals.
fred v

<font face="Verdana, Arial" size="2">Originally posted by pockets:
[B]Okay, gang, here's the scenario: Baldwin WWI gas mechanical trench engine, in 3.75" scale. I want to use high angle mis-alignment ball bearings like you find in pillow blocks. ]</font>

[pockets]

Fred V, very interresting. Would you have a brand name, model # or pic. That could save some head scratching.

Regards,
Greg B.