weld grinding tips needed

[daugen]

I'm not a welder, but I can refinish pretty well, and enjoy it.
I have a decent small hand grinder, with a variety of wheels for it.
And as you can see from this "in the door" pics, boy do I have some grinding to do.

This is a pretty unusual Gravely wing mower due to the Kawasaki motor. I already own one with a Honda 340 motor
on it; the Kaw is definitely a larger engine, and no longer made. Single cylinder with pressure lube and filter. And from the looks of it, pretty tired.
But it started and ran fine, without smoke.

I have always wanted to build a custom mowing rig for my Gravely garden tractor, with one wing out one side and one out the other.
40+50+40 inches is nice, I also have a 60 mower that I don't use at the moment.
And once built, with some custom bracket fab, paint it up really nice and take it to the local Grange Fair in August. There's some pretty neat stuff
exhibited there, and while the Gravely is too new for most classes, they do have some general interest stuff brought in, whatever will please the crowd.
Kind of worried that some kid may try to take home a souvenir, like a shift knob, but oh well.

So I'd like to make this nice, but it will never be "like new" so as long as it doesn't look like Frankenstein's child, three coats of Gravely red will look just fine.
But first I have to grind away. Are there any tricks? I've done this before, know I need to do this outside, because of dust and rust flying everywhere, mask and good glasses,
but how far down do I go? The light method is just smooth off the bumps and make sure nothing is sharp. If I grind more, it will be smoother, but am I just taking
strength out of the weld? Drew

 

[kevin37b]

In the second picture you have some holes to fill . The rest of your welds look good . Just make sure you stay on the weld while grinding not the metal around it . When you get the welds pretty , Then take a flap wheel and blend it in . The holes are what really show when you paint .

 

[Shield Arc]

Looks to me like you need more fill in some areas. I always keep the grinding wheel like this picture, also keep the wheel fairly flat. Stay on the weld until the weld is the same level as the base material. Remember in most cases the weld is harder than the base material. Once the weld is ground down flat I'll use a #36-grit sanding pad, then sometimes use a #80-grit sanding pad after that. I never leave a 90-degree edge, I'll take the sanding pad and put at least a 1/16-inch wide flat spot, so the paint will stick, and not so easy to flake off.

 

[k0ua]

I don't mean to be too critical or discouraging, but some of those welds (like in the second picture) look pretty wormy. Were they 6013 with an AC machine with a long arc? when you start grinding, you are liable to expose more wormholes. Try some 7018 on a DC machine or 7018AC on an ac machine and hold a close arc to see if you can make em look a bit better. As for the grinding you have been given good advice IMHO. I like to use a flap wheel when you get the majority high spots down and blend with the flap wheel. Again this is said in the spirit of "trying to help" not "trying to be mean".

James K0UA

 

[deereman75]

If it was my project, for the flat parts, would probably use the 7 inch, with either a fiber sanding disc or a flap wheel. You would have to be real careful, and I think I would use a small grinder for corners. I think it would be easy to make a mess with the big 7, but for me atleast the speed would be worth it, as long as you don't rush, you should be fine. If you don't have a 7, forget what I said, but keep your eye out for one, used ones are cheap, and the good ones never die.

 

[Gary Fowler]

I would use a 36 grit sanding pad for the whole grind job and just smooth it up and round the edges. I wouldn't try to make it look like it wasn't welded, just knock off the humps. You may have some areas that require more weld metal. Easy enough to do if when grinding it down, if you see you have low spots, just stop weld up the low spots and continue to smooth it out.

 

[daugen]

I keep thinking about those missed spots and how I'm going to fix that.

Here's a perfect example of stuff I want to weld, wouldn't an economical stick welder
do this mower deck work ok?

 

[ghenges]

I don't mean to be too critical or discouraging, but some of those welds (like in the second picture) look pretty wormy. Were they 6013 with an AC machine with a long arc? when you start grinding, you are liable to expose more wormholes. Try some 7018 on a DC machine or 7018AC on an ac machine and hold a close arc to see if you can make em look a bit better. As for the grinding you have been given good advice IMHO. I like to use a flap wheel when you get the majority high spots down and blend with the flap wheel. Again this is said in the spirit of "trying to help" not "trying to be mean".

James K0UA

Learning to lay a smooth weld eliminates most of the need for grinding.
The 7018 rod you recommend on a DC machine is my "go to" rod for just about everything. 6013 for tacking up and for pretty down welds. 5P for root pass on very think sections. 7024 for fast fill jobs.
All the young guys around here laugh at stick welding as old school, MIG is the way to go. I tease them MIG welding is like soldering -- like ***, I prefer full penetration and substantial heat.

A fellow (Frank) that helped me get started welding had butt welded 100's of truck frames (with no reinforcement whatsoever), and claimed not one ever broke. The shop manager of one company he did welding for said; "If FranK butt welded coat hanger wire together I'd hang from a helicopter on that wire while they flew me across Lake Erie, that's how much faith I have in his skill".

The 7018 isn't the best rod for out of position welding for the occasional welder. I've always said if I can roll it around on the floor, I can make it look pretty and also sound.

My grinding tools:

• 9 inch Milwaukee bust your balls angle grinder.
• Several 4.5 - 5 inch Metabo angle grinders, grinding wheels, braided wire cup brushes, wafer wheels
• 4 inch belt sander -- 60 -80 grit, makes beautiful rounded edges.

 

[k0ua]

I keep thinking about those missed spots and how I'm going to fix that.

Here's a perfect example of stuff I want to weld, wouldn't an economical stick welder
do this mower deck work ok?

In my opinion, yes you can easily do this with a stick welder. I would use 7018 or maybe 7014 for a wider smoother looking bead. Remember 7014 usually requires more heat, and lays down faster, but produces a wider/flatter/smoother bead which may be just what you want here. I am thinking DC welder here, you did not say if you had DC capability.

James K0UA

 

[daugen]

In my opinion, yes you can easily do this with a stick welder. I would use 7018 or maybe 7014 for a wider smoother looking bead. Remember 7014 usually requires more heat, and lays down faster, but produces a wider/flatter/smoother bead which may be just what you want here. I am thinking DC welder here, you did not say if you had DC capability.

James K0UA

I have neither, I didn't do the welding, the shop did. So I need to buy a first welder, something basic to make repairs like this. And now I know the rods to use, thanks.
So what you see is what I got, and now I have to finish it. When I saw that big opening on the one side, I knew I had more welding to do. My first welding actually.
So I'm a pure newbie here, but I understand good penetration.

 

[Soundguy]

hit it with a lil angle grinder to expose any holes that need to be filled. refill then.. then grind mor ewith a angle grinder.. then hit the flap wheel.. depending on how much you want to weld and grind and work it.. you can make it anwhere from ugly but strong to perfect...

 

[Shield Arc]

I didn't do the welding, the shop did.

You mean a welding shop did that?!!!!!!!!!!!!!!!!!!:thumbdown:

 

[k0ua]

I have neither, I didn't do the welding, the shop did. So I need to buy a first welder, something basic to make repairs like this. And now I know the rods to use, thanks.
So what you see is what I got, and now I have to finish it. When I saw that big opening on the one side, I knew I had more welding to do. My first welding actually.
So I'm a pure newbie here, but I understand good penetration.

I guess I misunderstood, I thought YOU did the welding. You mean that someone else did that welding? Oh.. dear..
I would suggest you get one of the Everlast or Longevity DC stick inverter welders or try to find one of the older transformer based Miller or Lincoln or Hobart Ac/DC welders and with some practice and the proper rod, YOU can do a heck of a lot better than the "welding professional" that did that. I have a PA160 Everlast that I paid $269 for about 3 years ago, and it has served me well for repairs and fabrication. I even TIG with it after I added a scratch start TIG torch with valve, and a regulator on the argon bottle. Daugen you should get yourself a welder, learn how to weld, and never go back to where ever you got that done at...good luck.

James K0UA

 

[k0ua]

You mean a welding shop did that?!!!!!!!!!!!!!!!!!!:thumbdown:

OMG. that is what I said.. I can't believe that a welding shop "Pro" would let something like that out the door. Holy Cow. I was going easy on the wormholes and bird turds, because I though this was HIS first welding project...Man oh man..

James K0UA

 

[daugen]

in fairness to the shop, they had a budget and more of an ugly but strong spec to work with, thanks Soundguy.
They were supposed to fix the front part primarily, but knowing I don't own a welder, getting it back this way
seemed kind of strange to me. It's a long time Gravely dealer and one I like, so I cut them some slack, they do other
nice things for me. And maybe what they have just done is get me off my proverbial behind and get my
first welder. I think an AC/DC stick setup would be just fine. I have a birthday coming up, hmmmm.

So....be critical on the front welds, not the sides and rear. Course this is a strange mower and it's kinda hard to tell which end is which.

 

[daugen]

hit it with a lil angle grinder to expose any holes that need to be filled. refill then..

I was going to do that, give it a rough grind to see if anything flakes off, falls out, whatever, then
when you say "refill" you mean reweld, correct?
I could make it all look perfect with Bondo or even plastic spackling, if it were a show queen, but I want to
use the mower, if only a little.

There's a field on the farm near the lawn area that is a perfect soccer field size area,
level, and sometimes that gets mowed more like a lawn so grandkids can kick balls there. And not get too many
ticks on themselves.

When I'm done with it, it will look like new. Surface prep is so important, particularly with metal.
But once I've ground it down a final time, if there are little dimples or cosmetic imperfections, tough. It's a mower.
I'd rather spend more time on the thorough cleaning, priming, and top coats. And using lots of blue tape to keep the end
result nice.

To make my double trailing rig, I need to rework this latest mower's hitch so that it pulls from a different spot.
Likely have some welding to do there too. I'm in no rush.

 

[k0ua]

Daugen, bondo would fill imperfections in a hurry, but since it is a mower, wouldn't the vibration and impact crack the bondo and have it falling out pretty quick?

 

[Shield Arc]

I think an AC/DC stick setup would be just fine.

OK, I'm new to all this, so please forgive the newbie question, but why do you think you need AC? :confused3:

 

[daugen]

Daugen, bondo would fill imperfections in a hurry, but since it is a mower, wouldn't the vibration and impact crack the bondo and have it falling out pretty quick?

Jim, sorry, of course, I was just making a point of how to do it "the wrong way", luckily, I'm dumb, but not THAT dumb...:thumbsup:
putting any kind of filler in something that vibrates is only asking for trouble. I only mentioned that because I don't (yet) know how to weld.

 

[daugen]

why do you think you need AC?

I thought the tombstone stick welders came AC and DC was an option, albeit expensive but offering performance benefits (less splatter) in some applications.
Clearly I know only theory and I'll defer to anyone else with knowledge.