# Machining welds, lesson



## Larry$ (Apr 24, 2022)

I found a piece of 1" steel in my "inventory" pile that would just fit the project. Irregular shape so chucked in 4 jaw. I recently made two short arm chuck wrenches. Boy does that make it easier. So started turning my project of the day with a sharp HSS too. Went dull, first pass! Sharpened it did a repeat. Couldn't see anything imbedded in the part. Tried again. it was a very interrupted cut, so I hadn't wanted to use inserts. But wasn't getting anywhere with HSS. Tried the inserted tool and it cut great. I got a nice smooth finish that then showed what my problem was, weld. Very distinct change in metal. I've machined through welds before with no problem but this stuff was really hard. It did turn beautifully.


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## Flyinfool (Apr 24, 2022)

It depends on what type of weld material it is. One of the things people are doing to prevent Catalytic converter theft is to lay several beads of hardfacing weld on the pipes that will rip the teeth off of a quality BiMetal recip saw blade. Some welds can be really hard.


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## Larry$ (Apr 24, 2022)

Flyinfool said:


> to prevent Catalytic converter theft is to lay several beads of hardfacing weld on the pipes that will rip the teeth off of a quality BiMetal recip saw blade.


Good idea, been a problem around here also. I've done hard surfacing on heavy earth moving equipment, really boring work!


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## MrWhoopee (Apr 25, 2022)

Difficulty machining welds should be anticipated. It isn't always so, but more often than not. Annealing can help, sometimes.


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## Provincial (Apr 25, 2022)

The type of weld material and carbon content of the base metal can combine to make a very hard weld.  High carbon steel does this often.


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## Manual Mac (Apr 25, 2022)

I have found stick welds much easier to machine than mig welds.


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