# Best Cut Off Wheels And Sawzall Blades?



## E350 (Jun 1, 2015)

*Hey guys*:  I recently bought a Miller Thunderbolt XL stick machine to do some reconfiguration of the hitch coupler on my 1950's Dodge 1/2" ton utility trailer.  I am lowering the A-frame for better alignment with the tow vehicle, cutting/grinding off the bale-type hitch ball coupler (which friggin' popped off going over a speed bump recently), adding a 1/4" thick 3" box stinger between the A-frame which will extend about a foot longer than the A-frame to make the tongue longer for less jack-knifing when backing up, and installing a Bullydog ball hitch coupler.  (The stinger will be welded between the existing 3" angle and welded into the trailer frame under the bed at the other end.)

The existing A-frame is 1/4" thick 3" angle which is lap welded top and bottom onto the 1/4" thick 6"x 2" box trailer frame (the original frame was 6" x 2" "C" channel, but it is boxed where the A-frame connects).

I started grindin the weld beads flat and then running a 3/64" thin 4.5" diam. H.F. cutoff wheel between the 1/4" thick 3" angle and the 1/4" thick 6" x 2" box.  It is working good, but the 4.5" cutoff wheel can only go about 1.25" deep.  I then used a "metal" blade on my Porter Cable Tiger saw in the groove which I had made with the cutoff wheel but it really couldn't cut much, probably because it is not the right blade, if there is a right blade.

So my questions are:

1.  Are there better cutoff wheels that I should try?

2.  Are there steel blades which will work in a Sawzall type reciprocating saw?

3.  Is there another technique I should consider for separating these components?

And yes, I have a bunch of scrap metal to run pads of beads before I ever put an arc to the trailer.

I was going to use 6010-5P+ or 7018 rod for this.  But if you guys also want to make some suggestions for rod, I would appreciate it.  But first things first, I've got to separate the A-Frame from the trailer...

BTW, I have a Millermatic 350P which I weld somewhat ok with (although I often grind off my welds and redo them) so I am not a total newbie.


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## Silverbullet (Jun 1, 2015)

I have tried the saws all blades from Walmart I think B&d makes them the teeth look kinda gray and flat but they really cut well and take a bit of punishment too. They have a couple lengths offered. Not costly but cuts rings around my other metal cutting blades. Abrasive cut off blades can be had in many sizes just need the right arbor on what your using. I've been using the 4 1/2" ones from hf if you don't jam them or get the caught up they hold up pretty good , I've used others and had no better luck. Porta bands work if you can get them where you want to cut . For welding my favorite rod is the 7018 , the seem to work for my machine and a little rust don't slow them down for penetration . I can lay some pretty welds with them . Seems the 6010s are a little fickle getting them to start. But it's up to you try both see what works well for you. Try to make sure you get good penetration in the metals don't want them to pull apart on a trailer.


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## brino (Jun 1, 2015)

Silverbullet said:


> Abrasive cut off blades can be had in many sizes just need the right arbor on what your using



The usual problem is the metal shield around the abrasive wheel won't allow a larger diameter wheel. I do NOT recommend running without the shield; you want it there if (when?) one of the wheels disintegrates at speed! And it's usually too easy to twist the wheel in the groove when cutting by hand.

I have however extended the shield on one 4-1/2 inch grinder to allow 5 inch wheels after I got a bunch of them at a good price.

Perhaps you can use this project to justify a nice 7 inch grinder. 

-brino


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## turnitupper (Jun 1, 2015)

Get yourself a cheap 9 inch angle grinder, preferably one with a soft start, for the cutting. A lot of people think a 9 inch is dangerous and they are if they are used incorrectly but they will remove crappy welds in 1/4 the time it takes a 41/2 grinder. Just take care and USE the handle supplied.
John.


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## JimDawson (Jun 1, 2015)

Maybe I'm not understanding the problem.  I normally just cut the weld beads then smack the part that I want to remove with a big hammer to remove it.  But maybe you can't get to all of the beads with the grinder.

Milwaukee makes bi-metal metal cutting blades for the SawzAll.  They work pretty good.  A hot wrench (cutting torch) would probably be my choice for this project.


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## E350 (Jun 1, 2015)

*JimDawson*:  Yep, about two inch of the top weld bead is under the bed, which I would prefer not to raise if I can avoid it.  I am rewelding the A-frame 3" lower, so access won't be an issue on the reweld,  but access is a problem on the removal.


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## JimDawson (Jun 1, 2015)

If I understand correctly, maybe you could just cut the 3 inch angle off flush with the bed, then just weld the new pieces under the A-frame as planned.  It doesn't seem that the angle would be in the way of the new pieces.


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## markknx (Jun 1, 2015)

Got a picture that would help us help you. as Jim said millwakee makes a good blade lenox, dewalt are all good get a few if you are working in the kind of space it seems like you will need them.
Mark


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## E350 (Jun 1, 2015)

Here are some pictures.  A Makita 9 inch angle grinder with a 9 inch cut off wheel would be quite helpful if wheel is just a thin as the 4.5 inch wheels.
But if a reciprocating sawzall blade would cut the welds, that would allow me to cut the bead under the bed without having to raise the bed to do it from the top.
Hmmm...  Looking at the pictures, I guess the top weld would actually be considered a "butt" joint?  While the bottom weld would be considered a "lap" joint.


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## markknx (Jun 1, 2015)

how far under the bed does that top weld go? if not to far grind as much as you can cut the bottom weld and try driving a wedge in between the frame and hitch. Good chance that weld will pop.
Mark


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## E350 (Jun 1, 2015)

I went to Lennox website and this 210617614GR  LENOX Gold® POWER ARC CURVED EXTREME METAL CUTTING RECIPROCATING SAW BLADE might be the way to go:

http://www.lenoxtools.com/pages/pow...reciprocating-saw-blades.aspx#ltImg[mixed]/2/

Interesting automated side by side comparison with a Milwaukee which did 13 cuts in ASTM A36 mild steel plate and the Lenox which did 68.

Only one amazon review by R. Yee:

"Best blade I found to cut metal with saw saws (sawzall?) use cutting oil and go easy this blade will last longer."

http://www.amazon.com/21067614GR-Reciprocating-Medium-Cutting-6-inch/dp/B0009MZJ6O/ref=sr_1_2?s=hi&ie=UTF8&qid=1433211558&sr=1-2&keywords=LENOX+Gold®+POWER+ARC+CURVED+21067614GR

If I buy the blade and use it, I will report back.  But after looking at my pictures (uploading them made me look at the project order a little differently) the current height of the A-frame is perfect for sitting on a stool and grinding off the existing hitch coupler.  So I think I will leave the A-frame to trailer welds in place now, grind off the hitch coupler, and then see if with the angle iron free from the hitch coupler if I can just break the remaining welds loose with a wedge and sledge as Mark suggested.  Thanks guys, I will report back how it goes.


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## EmilioG (Jun 1, 2015)

AFA Cutoff wheels, 3m Cubitron III is best hands down. The best grinding wheels also, Cubitron 3  3m,


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## E350 (Jun 1, 2015)

3/64"  =  0.046875"
Cubitron II 4.5" diam. are 0.125" = 1/8"  (Couldn't find Cubitron III on the 3M website...)

At 3/64", the H.F. are thinner. So if I protective gear up, discard them immediately if I drop the grinder, I will probably continue to use them unless I can find an equally thin wheel.  Here's my 3M grinding helmet:





I am wondering if there is a leather jacket with good front neck protection?


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## markknx (Jun 2, 2015)

Most leather welding jackets should go high enough that the shield and jacket will over lap
Mark


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## Terrywerm (Jun 2, 2015)

I've used a variety of reciprocating saw blades and have had good luck with the Milwaukee and Dewalt blades, haven't had the chance to try any Lenox blades yet. My Sawzall used to cut ALL of my metal stock before I got my power hacksaw.


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## charlie4128 (Jun 3, 2015)

For sawzall blades I have used Lenox for many years they are are not cheap but cut straight and last the longest as long as you let them cut and don't lean on them to hard 
For cut off wheels had best luck with Norton wheels they last a good while thought not cheap and may not be available locally http://www.grainger.com/product/NOR.../rp/s/is/image/Grainger/33N521_AS01?$smthumb$
they work well and not that thick


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