hey guys welcome back to all comm so today I have John Thompson with fir'd here with
me in a previous video we did a we did some weld discontinuities how to avoid them but
if you've been welding in the field or in the shop for any amount of time you know that it's
inevitable you're going to end up with a well of discontinuity so we went ahead and replicated
that I put a root in here with some intentional lack of fusion and I want to talk about talk to
John about some of the ways I can get rid of this so then get back on track put that well back in
and keep going obviously I can't just Waldo ver that because the lack of fusions there I'm just
gonna cover it up if I continue to well so what I have to do is remove that section of weld and
just do a tie in and and fill that pass in so John throughout my experience most the job sites I've
been on I've only had access to these three wheels so I have a quarter inch hardrock azarkh wheel and
a cut-off wheel over the years I've learned that it is not appropriate to use a quarter inch hard
rock that you know especially since I started talking to folks in the abrasive industry now
supposed to use a quarter inch hard rock on here desert wheels out of the question because I can't
get access it's not I don't have any abrasive material on the outside of this wheel and the o45
cutoff wheel like it you know it's like digging a big hole of the teaspoon so that leaves me with
the quarter inch hard rock and this is typically what I've seen a lot of people use and you end up
and deteriorate that edge because that's not the purpose of this wheel so tell me why I can't use
this in this situation and then tell me what you would come up with there would be the appropriate
abrasive for this of thing you know the viewers at home don't know exactly what they're what they
should be using you have to make the adjustment on the way the wheels designed realistically the
cutoff wheel is designed to cut but it's so thin especially on a 45 cutoff wheel that as you said
you can't get enough profile to get it away you'll make a bunch of little cuts but it won't really
work for you obviously the segmented flat disc or you call it desert wheel nothing wrong with
that but that's really designed to run flat it's there's really nothing on the side right to where
it things out so in reality it won't let you get in to where you want to be able to go but here's
the difference it comes this is a grinding wheel right all right however most of the time what
you're using it for is you're using it to take off some scale and you're using it to prep the
plates by pushing this product you're using it to prep the paint's they're plates to put the bevel
on that you want and that's what it's designed to do this wheel is designed to work between fifteen
and thirty degrees so when you're pushing this into place your body naturally will put it that
way so it's reinforced at the top the middle and the bottom so that the wheel itself will give you
excellent wear life and allows you to give you very aggressive and safe wheel to use but it's
reinforced in the middle as well as the top and the bottom when you try to go on edge with this
what happens is now you start to fight it and the wheel itself can break down but you need to
grind so we've got to give you a grinding wheel not a cut-off wheel not a flap disc not a thick
grinding wheel we have to give you a wheel it's designed to grind on edge and this is where the
eighth inch wheel is designed to be able to do this is reinforced on the outsides you can see
a reinforcement layer right here it's also reinforced here and this grant is packed so
that is designed to come in it's thicker than the cutoff wheel so it tends to take a wider so
it will bury itself in real deep it tends to take a wider net wider birthing area in there exactly
the other aspect behind it is that it's intended to grind on edge so to come in it'll fit in to
where you want to be now this is pretty wide and that's where a lot of guys too will turn around
and say well I need the wide wheel because I got a lot of well I've got to get out that's what your
arms are for in reality what your arms are for is to take this wheel turn the grinder a little
bit so that you're actually riding on the bevel just outside of the bevel and scoop this out now
instead of just the whip thickness of the wheel because you've got to turned you'll actually wind
up with a wider face in this case you're gonna pull because you want the control if you push
you're gonna keep falling into here so you don't push it like you did with your quarter inch wheel
you pull it so you take the crown off of the bad spot then a little farther down pretty soon you
get it all even open it up a little bit and now you've got a nice shallow bed to lay in your other
whales go ahead and hook it up to the hook it over to the grinder we'll go ahead and clean it
out okay so right up here head like a high spot so I went ahead just took care of that while I was in
here but the left-hand side of the weld was tied in good to the left side of the plate left me an
opening on the right hand so I couldn't get access with that welding rod so like John was saying even
though this is an eighth inch wheel it's designed to run on the edge of that wheel I can turn it to
the side and kind of open up and give myself a little bit wider of an area versus trying to
use a quarter inch wheel that's not made for this and just force it in there to get that profile so
I was able to get in there clean everything back down to the backing strip and I'll just go ahead
and do a restart and then I'll do a termination up here okay so we went ahead made the repair
got rid of that lack of fusion on the sides there I'm just about brought up to where where I was on
my initial route pass so now I can go ahead and do my intermediate fills and then the I can go
ahead and cap it right after that so pretty much that's how you would repair that you want to cut
out that old well the bad weld gained access to it put you another pass in there so you tie back
into the backing strip get all three pieces the left side right side left side right side
and the backing strip all tied back in again then just go ahead run your intermediates or your fill
passes and then you should set yourself up for a cap since we're talking about abrasives you just
want to make sure you're using the right product if you use that quarter inch wheel on the edge
which is not designed for you're gonna end up with problems at that point it could split and corrects
s vibrations thrown the wheel off balance so you don't want to do that use the appropriate wheel
for the task at hand if you don't have the right stuff go get it all right I know what you're gonna
say I got this big old crater right here but I'm not worried about that because when I come back
through here and run my intermediate or my fill passes all that's gonna get covered up it's gonna
blend in smooth I'm gonna tie in there I'll have enough penetration to get in there and dig all
that stuff out and put to good welds right over top of it and then I'll be ready for a cap so I
don't have to worry about this because I hate saying it's gonna get covered up but it's this
this whole area right here is gonna disappear if that was porosity lack of fusion swag inclusion I
would not leave that here but because it's just a crater for a tie-in I'm not worried about it
once I put those fill passes in there it's all gonna melt in alright next up we have a filler
weld it's another common joint everybody should be used to we went ahead and did about 3/4 of
the weld correct meaning 50% of the weld is tied on on either side of the plate and then the last
side I went ahead and put in unequal leg lengths so I just picked that working GLE up a little bit
higher than I needed to and have more of the the weld on the horizontal plate than I do on
the vertical John I want to cut that last probably 25% of that weld out or 35% of that weld out so I
can do a tie-in do a restart and a tie-in and finish that back off to where I have an equal
bead throughout the whole piece what would be the best abrasive that we have here to get rid
of that or again you've got a control oh you're gonna be taking material mmm so in essence you're
still going to be using an edge grinding wheel because if you come in and such with a cut-off
wheel again that you've got it's just too thin right you're gonna wind up undercutting you're
gonna wind up with taking but to your parent material that you don't want to take if you come
with the segmented flap disc or their zerk wheel what you're going to wind up really succeeding
in doing is you'll be able to knock this down and get it flush but you'll have a lot of over grind
in the area you're gonna have a lot of other issues is such cosmetically to work with you
and this is still not intended for you to come in on edge because you're still positioning yourself
where what you really want to do is you don't have enough here to be able to use the wheel you if it
was all you add in a box you could come at the top [ __ ] it and and push your way through and
work with it the problem again that you're going to run into though is the edge of the
wheel is going to be doing possibly some undercut coming back in with this eighth inch wheel which
you're going to have is you're going to have the advantage of being able to come through here and
you're gonna be able to literally come at an angle and use it that you clear the clamping
nut and clear the way and you're gonna be able to just scoop that out of there could be able to pull
it through because remember you push this so you can control it that way it's good give it a shot
you've got the rotation of the wheel and you're using the edge of the wheel you'll notice that
this because it's designed to be ground on the edge you'll notice it's not beveling it like
you would with a quarter inch wheel so you're not winding up with this feathered edge up at the top
this is still keeping its shape so coming down here and coming into that well the way you did
you're taking the convex part of the well and you're turning it flat again you're getting it
out so that materials in also by staying with the weld area that's it you're parallel outline that
you've created cosmetically does not exceed the original line that you clean the scale off with
so you're taking this wheel you're using the edge you took the convex part of it took the crown off
and started to make it concave and then started to just scoop it out you also didn't undercut if
you look at both the top and the bottom you have control here that you don't undercut and that's
usually a big problem because now all you're gonna do is weak in that upper area when you go
to weld in anyway that's why you have control with a wheel design for edge grinding as you'll notice
that you did not go past your original clean area which means after you've welded cosmetically that
whole lines gonna look the same and that's why you want to use a wheel that you can use that much of
the edge for okay so I went ahead and dish this out right back into this area this is probably
about where I made the transition earlier to get that to get that unequal leg length so I took it
back just a little bit further I got a nice little dish in here kind of like a I would want a crater
when I do my tie ends that way you know I don't get any cold lap in there so I went ahead dish
that out so I've got this area I'm gonna start the electrode right about here tie back into
here wants the puddle washes over where I left that grinding area I'll continue on and complete
the joint okay so you can see I got the tie in right here everything else went pretty smooth
it's nice having the right tools to work with having the right disks a your disposal I've used
other wheels too to cut welds out before and you end up making a lot more problems than you need
to deal with so just by switching out and using the appropriate disk you know something you can
actually grind on the edge with you're not only gonna prolong the life of your abrasives but you
know you're gonna get better results with your welding as well alright so we've talked about
well repair it a little bit you know getting into the different types of wheels but let's talk about
change gears a little bit and let's talk about base metal preparation so I'm out in the field
I don't have access to a plasma cutter or oxyfuel torch I have to put a bevel on a piece of plate I
have to take off the mill scale what would be the best products or you know the type of abrasive to
use for this application okay well now you've got actually two different challenges challenge
number one is mill scale itself mm-hmm mill scale there's a 100 percent adhesion mill scale actually
comes up when they have the billet material and when it hits oxygen is when it forms the
scale so it is in every nook and cranny on this whole surface you know a lot of people will come
in and stuff and say well if I can wear off the mill scale and you'll see it sometimes when you
first grind on it you get it like a shiny black and then right on you break through and it gets
shiny silver and then you break through again and break through again what you're literally
doing is you're literally trying to buff your way through with that the challenge you run into
with that is that it takes forever so you're also trying to bevel the plate now the nice
thing about beveling a plate or taking off even some plasma draws is that you can you can take
material because you're trying to set up stock and so on a plate like this for instance we're going
to go back to the quarter inch to press Center grammo realistically what you've got is you've
got a a conglomeration of grain that's pointed in all different directions it's not oriented in
one direction like what you have when you have a cold abrasive material we had had an earlier
video you know almost a year and a half ago about coming in and showing taking-off mill scale with
the epitome of the disc and that's getting a grinding wheel quarter inch made for concrete
because what that contains is silicon carbide instead of the impact grain of coming down at
aluminum oxide or zirconia or even ceramic which you do is it picks it off it literally
comes in one or two passes all that mill scale really moved and if you want to bevel you've got
a quarter inch grinding wheel it's it's it's designed especially for taking the top of the
material but if you want a bevel with it you can bevel it let's go ahead get it to it okay so what
I'm gonna do is I'm going to take off about one inch of this mill scale using that quarter inch
hard rock on both sides and then I'm going to use the Younger switch over to that the zerk wheel the
40 grit and I'm gonna try to put a thirty seven and a half degree bevel on there and we'll just
go ahead and double-check it with the protractor alright so as you can see with that quarter inch
wheel I used to push technique to get everything off all that mill scales off on both sides I'm now
going to use the desert wheel and I'm gonna do a pull technique and try to get to that thirty
seven and a half degree bevel there you go not too bad a little bit more and you know I think we're
within a half a degree or so alright guys hope you're able to learn some additional information
about abrasives I know John's taught me a lot today there's a bunch of things that I didn't
know that uh thanks for taking the time to shed some light on this stuff I mean I know welding
abrasives are you know whatever is on the grinder I'm gonna use to the best of my ability and try to
get what I can out of it so hope you guys enjoyed the video learned some stuff about doing some wild
repairs as well as bevel in your own plates at home we want to thank John for coming out here
giving us all this great information go ahead drop something in the comments down below make
sure you like and subscribe to the channel until next time make it well better than your last