Looking for a shot fan clutch...

[ironworker40]

Well, you either know a lot more than me about fab work or less.... not sure which.

My immediate concerns with that are the difficultly of making a good solid consistent weld on the wall of a small pocket like that, possible warping due to uneven heating, loss of hardness in bearing seats if they are hardened and finally the difficulty of machining the welded material. In contrast making an insert is a simple straightforward operation, as is a simple boring operation on the fan clutch. There's some risk of thermal damage brazing but it would be a lower temp more controllable even heating so less likely to cause problems. Also, if you machine down an old fan clutch so make the insert you don't need to deal with internal thread cutting and the machining operations reduce to simple boring and turning.

Please post a pic of the shaft after you take it apart because I have a picture in my head of what I think It looks like but I need to see it.
It can be tig welded with minimal heat. That would be the way I would do it.

 

[ironworker40]

Here is an example of a tig weld I did last week. This is a 1968 original Harley Davidson gas tank.It was leaking just under the stud that was welded at the factory, You can see some of the crack. So this is the first pass. I welded multiple passes up to the stud. Now this is the back side of the tank thats why the paint isn't buffed and shinny, but notice that the heat only radiates out a 3/8 of an inch or so were the paint burned off. When this was done the paint on the top and front was still perfect.

 

[jaluhn83]

Shaft is buried in a box at the moment - it's similar to the stock fan clutch shaft - female 1-1/4" thread about 1" deep. The TIG setup I have would be very difficult to get in far enough to weld especially at the bottom unless you stuck the electrode out a fair bit beyond the cup and relied on the gas filling the entire pocket which might work, but would it would still be difficult to access and get a good weld.

Even with TIG you still have a hard weld bead that's not going to be fun to machine.

I don't doubt that you *could* do it that way if you really wanted to.... what I don't see is why that would be preferable to using an insert. Insert just seems much easier and less complicated to me.

 

[jaluhn83]

Insert would be easier to cut threads in too - is you're using a lathe then it means you're not cutting into a blind pocket (assuming a tubular insert), and you could even tap it assuming you could find the right tap. Weld and then thread mean a fair amount of boring into a blind hole in hard rough metal (not going to be easy on the cutters or lathe) and then threading in the same blind hole with hard steel....

 

[typ4]

IH water pump and ford bolt to the engine exactly the same, I just put ford pump on one of the s1600 uhaul engines a couple weeks ago.