How would you rethread this part?

Making the insert out of stainless could present a problem. Stainless tends to gall. Maybe not so much when threading stainless to carbon steel, but still could gall. I fastened ¾” stainless nuts and bolts together just one time on a flange. Tried to unscrew, everyone of them was held fast like they had Loctite. Had to use a cut-off wheel, not fun.

And just using a tap to rethread will leave you with cross threads. And the cost of the tap!

I would just sell the one you have and buy the correct one. Especially if you say you have limited machining skills, sorry…Dave
 
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Stainless on stainless is bad news. Even if you use anti sieze it still sometimes galls and seizes. On my bass boat they used stainless bolts and brass nylock nuts. (With a 250+HP outboard no less) I have noticed when power installing stainless on stainless I almost universally get a lock up if its more than a few turns, but when tightening by hand its only 50/50.
 
If you were to just re tap it I think you would be asking for trouble . What threads you would get would be extremely weak. Let alone the stripping and cross gulling . The barrel would be ruined . That cost would really suck. I'd say machine an adapter with the I'd being the 36 tpi and the other end turned and the 28tpi . You could loctite it or pin it.
 
As always you folks amaze me with your knowledge and willingness to share. As I said in the original post, I don't think I'm ready to tackle this yet but your info was great. Think I will buy the part as a gift to son-in-law then take old part to see if I can do some of the procedures before selling the old part. I think I can at least make a short extension just to see if it will fit etc.

So thank you to all who responded. Time to go raid the piggy bank and order that part.

Do have a few questions regarding a few of the responses. For instance, what is a Dutchman repair in the machine shop world? Googled it and I get the woodworking patch and pluming patch both called Dutchman but no reference to machining. And I'm a pure Dutchman myself so I need to know this. Second, how big would you folks make the threaded insert? Is there any rule of thumb to follow, or as reasonably large as space will allow?


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A Dutchman is simply a hole drilled and reamed parallel with the axis of the inserts, but offset from center such that it is cut equally into both the insert and the parent part. Then a pin (or can be a screw/bolt if future removal is desired) is pressed or driven in. Properly done they are a light press fit and are flush to slightly below the mating surfaces, if there are any. It serves to key the components together.
 
Tony Wells said:
A Dutchman is simply a hole drilled and reamed parallel with the axis of the inserts, but offset from center such that it is cut equally into both the insert and the parent part. Then a pin (or can be a screw/bolt if future removal is desired) is pressed or driven in. Properly done they are a light press fit and are flush to slightly below the mating surfaces, if there are any. It serves to key the components together.
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Great info, I actually get it.


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