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 Post subject: welds are the devil
PostPosted: Tue Dec 20, 2011 12:53 am 
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Joined: Mon Oct 17, 2011 11:50 pm
Posts: 168
Location: San Diego
I bought a older (ok .. real old) tilting vise. When I got it home I noticed that it
had so many drill holes in it .. that there was no way a set of parallels would sit
right in it.

So .. I took the mig .. and just welded a bunch of puddles into the drill holes.

I thought .. heck .. i'll just take an endmill and level the weld bumps down.

Jezzzzzz .. I never knew that welds were that hard. Its was horrible. I ended up having
to take my angle grinder with a cutoff disk .. and leveling it some what .. then
finishing it with a flycutter ( a zillion light cuts ) with a carbide cutter in it.

Oh .. and that was the first time I got to use my flycutter .. and .. its the coolest thing.


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 Post subject: Re: welds are the devil
PostPosted: Tue Dec 20, 2011 10:25 am 
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Joined: Tue Oct 13, 2009 9:56 am
Posts: 54
Location: Birmingham, Al
I hope you didn't warp it. That heat really moves metal around.


be


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 Post subject: Re: welds are the devil
PostPosted: Tue Dec 20, 2011 3:27 pm 
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Joined: Mon Oct 17, 2011 11:50 pm
Posts: 168
Location: San Diego
Yea .. it was pretty shot .. I really doubt that I would ever get it to be
considered "true and accurate".

I only got it because I want to use my tailstock sometime. and to use my tailstock
I have to make a gib/shim for it ... and to make a gib/shim .. I need to take some
bar stock and make it into a parallelogram .. and to make it into a parallelogram I have
to machine barstock at an angle ...

lol .. get the picture .. This will work fine for that and other non critical projects.

Looking back .. I do wish I would have got the tourch out and braised some puddles
on it .. would have machined a lot easier.


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 Post subject: Re: welds are the devil
PostPosted: Tue Dec 20, 2011 4:36 pm 
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Joined: Fri Dec 22, 2006 5:41 pm
Posts: 451
Location: Lewes, DE
Hi There,


mikeamick wrote:
So .. I took the mig .. and just welded a bunch of puddles into the drill holes.

I thought .. heck .. i'll just take an endmill and level the weld bumps down.

Jezzzzzz .. I never knew that welds were that hard. Its was horrible. I ended up having
to take my angle grinder with a cutoff disk .. and leveling it some what .. then
finishing it with a flycutter ( a zillion light cuts ) with a carbide cutter in it.


What was the filler material you use? Most welds in cast iron are done with
high nickel content filler if you want to machine it afterwards. Otherwise the
welds are very hard indeed. Also, the transition area is ofter still very hard
unless post welding heating is employed to prevent them.

Good Luck!
-Blue Chips-
Webb


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 Post subject: Re: welds are the devil
PostPosted: Tue Dec 20, 2011 6:31 pm 
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Joined: Mon Oct 17, 2011 11:50 pm
Posts: 168
Location: San Diego
ahhh .. I really didn't use filler per say .. I just grabed my mig and welded some puddles
using whatever wire you normally have in a mig.

Thats alright .. a project is a project .. and this one has already taught me
bunches ... at one time .. I had my machine rattling so bad .. that all the
handles unscrewed themselves and fell out .. ahahah ..

The HSS endmill was really unhappy with what I was doing to it .. .
but the carbide tip in the flycutter got a little revenge ..

I come from that Idiot school of thought to where you don't know how far you can
go .. untill you go past that point.


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 Post subject: Re: welds are the devil
PostPosted: Tue Dec 20, 2011 7:21 pm 
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Joined: Fri Dec 22, 2006 5:41 pm
Posts: 451
Location: Lewes, DE
Hi There,

mikeamick wrote:
ahhh .. I really didn't use filler per say .. I just grabed my mig and welded some puddles
using whatever wire you normally have in a mig.


You misunderstood me. I mean what type of metal was used to
fill up the holes. Plain steel is a bad choice for cast iron because
the rate of contraction of the steel, as it cools is greater than the
cast iron and cracks can develop between the cast iron and the filler
metal.

I come from a "stick welding" background and most filler metal used
in welding cast iron contains a high percentage of nickel because of
its increased ductility compared to plain steel. The rods I use are
99% nickel and are for "machinable" welds in cast iron. I've used them
to repair my compound:

Image

Image

Good Luck!
-Blue Chips-
Webb


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 Post subject: Re: welds are the devil
PostPosted: Tue Dec 20, 2011 7:25 pm 
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Joined: Tue Apr 13, 2010 7:31 pm
Posts: 68
Location: Palmer, Ma
mikeamick wrote:
I come from that Idiot school of thought to where you don't know how far you can
go .. untill you go past that point.
That's how I've justified every bolt that I've over tightened and snapped.
We must have been in the same class :lol:

Griz


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 Post subject: Re: welds are the devil
PostPosted: Tue Dec 20, 2011 9:21 pm 
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Joined: Mon Oct 17, 2011 11:50 pm
Posts: 168
Location: San Diego
lol ... I didnt use ANY metal ... I just welded the holes shut and in the indentations until
there were NO MORE holes and indentations .. just globs of weld over where they used
to be.

Ugly .. but it gave me something to flatten out.


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 Post subject: Re: welds are the devil
PostPosted: Tue Dec 20, 2011 9:46 pm 
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Joined: Sat Jan 04, 2003 10:45 pm
Posts: 309
If you did not use any metal, what did you fill the holes with? You had to use something!


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 Post subject: Re: welds are the devil
PostPosted: Tue Dec 20, 2011 10:07 pm 
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Joined: Mon Jan 06, 2003 8:39 pm
Posts: 274
Location: Roscoe, Illinois
The filler metal was whatever type of wire happens to be in his welder.
Welding iron with steel rod causes a hard 'white iron' area around the weld from the rapid uncontrolled cooling of the welded area, I think. It could be in part due to the graphite (carbon) in the iron being disolved into the weld area, causing a high carbon 'steel' transition area between the weld and the iron. Nickle won't cause the same problems with the carbon, you will still have a weak transition area between the base metal and the weld.


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 Post subject: Re: welds are the devil
PostPosted: Wed Dec 21, 2011 9:56 pm 
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Joined: Wed Mar 15, 2006 11:10 pm
Posts: 886
Location: Farmington, NM
For future reference, preheating the vise body to a nice hot temperature then a very slow cool would reduce weld hardness and warping tendencies. Normal steel MIG wire would not be a good choice, use fillers as suggested above.


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 Post subject: Re: welds are the devil
PostPosted: Sun Jan 01, 2012 2:07 am 
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Joined: Sun Jun 08, 2003 11:52 pm
Posts: 4608
Location: NW Indiana. Close to Lake Michigan S. tip
Ya, agreed here. Get better at getting information on how any job is done. Welding cast iron is easy, and not. These posters have good info and procedure.

Brass would be good unless the iron has a LOT of carbon, at which point the brass wont stick. Sometimes called dirty iron, it is actually quite good stuff, just opposite chemistries are the bug in the jar.

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Be Alert! The world needs more Lerts.


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