Best Cut Off Wheels And Sawzall Blades?

[E350]

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 cutting the welds off and then running a 4.5" 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.

[Aeronca41]

I've settled on Lenox recip saw blades. Have also used Dewalt, Milwaukee, Craftsman, and a couple of no-names I picked up somewhere--I keep going back to Lenox. Their bi-metal, at 14 TPI for your 1/4" stock would be my choice. You want about 3 teeth in the material. Don't run the saw too fast, and adding some cutting oil helps--but use an OA torch to burn the oil off before welding. Where possible, I use a portable metal cutting band saw, but they're a bit bulky and have limited thickness capability--but they really cut nicely!

I'm scared of buying HF grinding and cut-off wheels. Things that spin really fast close to my body scare me, and I'd rather spend a couple of bucks on an American brand name. I buy something like Lenox, Norton, Dewalt-they could fail, of course, but they seem to be far better balanced than the Chinese stuff. Not a place to save a buck and regret it later-those pictures on the web of guys with broken wheels embedded in their faces are a good incentive to buy quality, use them carefully, and wear protective gear. Some of the guys on this forum have recommended Lehigh Valley abrasives but I haven't tried them yet.

Not sure what you mean about running pads of beads on scrap metal. As you obviously already know by choosing stick vs mig for this job, excellent penetration is key to safe welds. There are lots of guys here FAR more qualified than me to give you welding guidance, and I will leave that to them. You will need to do some bend testing on your welded scrap to be sure you have it right consistently before doing the real welds. Enjoy!

[snowbird]

Best by far cutting disks are sg elastic by pferd. if you have a fast and smooth grinder they make precise cuts in whatever you give them.

https://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CB4QFjAA&url=https%3A%2F%2Fwww.pferdusa.com%2Fproducts%2F206j%2F206J01P.html&ei=I_NsVZvhEIPlsASF4oIw&usg=AFQjCNGdC1b55y6SZhXTED4JWODrhkXd-w&sig2=4-AILvIw6PL6oM4zEgRNug&bvm=bv.94455598,d.cWc

And NO, i don't work for them

[E350]

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+21067614 GR

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.

snowbird and aeronca14: I looked at the SG-Elastic on the website you provided. 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. Thanks guys, I will report back how it goes.

[Aeronca41]

The pix of the front of your trailer takes me back to when my dad had his old Hobart in the bed of his '53 Dodge until he got his welding truck built. Nice sturdy old truck, and makes a great trailer.

Hope you do well on your project-always good to hear a guy thinking it through, then thinking some more! I really enjoy this forum because it is great just to see how people solve problems, and there is a vast amount of knowledge here free for the asking.

Snowbird, thanks for the steer on the cutting wheels-will have to try some.

[snowbird]

E350, at 3/64 these hf disks are 0.046 in thick, personnally i use pferd stainless type, 5 inch x 0.030 or 0.040 they work as a razor blade in butter on sheet metal up to 2 inch shaft

https://www.pferdusa.com/products/206f/206f05/206f050302P.html

Note: i have a dedicated 20 years old 4.5 in metabo running these 5 inch disks. it's a very smooth running grinder, turning on something that vibrates or wooble, like my cheap grinders might be impairing their performance.

[E350]

snowbird: Can you use the stainless cut off wheel for mild steel? Also the website says that the arbor is 7/8" for the 4.5 and larger wheels. Does your Metabo have an arbor that large? I have three 4.5" Makitas but their arbor is only 5/8". If they work on mild steel, I would be interested in trying those cut off wheels (they are even thinner than the H.F.s!) but I need overcome the arbor issue.

[WillieB]

snowbird: Can you use the stainless cut off wheel for mild steel? Also the website says that the arbor is 7/8" for the 4.5 and larger wheels. Does your Metabo have an arbor that large? I have three 4.5" Makitas but their arbor is only 5/8". If they work on mild steel, I would be interested in trying those cut off wheels (they are even thinner than the H.F.s!) but I need overcome the arbor issue.

Depending on when you bought it, the grinder will have come with an adapter for 7/8" wheels. If not, Home Depot and a thousand other sources can provide them. By the way, I need one for 1" center hole. Anybody know where I can buy one?

[Cgotto6]

+1 sg elastic is hands down the best for abrasives. Only thing I run for my 14" chop, grinders and cut offs and multi flaps.

[E350]

I am a bonehead. I was standing looking at the Makita grinders this morning including the ones that I own, and yes the locknut and inner flange are designed for 7/8" arbor wheels.

I will try the cut off wheels that you guys suggested.

[snowbird]

Depending on when you bought it, the grinder will have come with an adapter for 7/8" wheels. If not, Home Depot and a thousand other sources can provide them. By the way, I need one for 1" center hole. Anybody know where I can buy one?

Are you on the way to re-purpose worn 12-14 inch cut off wheels? rated for 1440 rpm on your 10,000 + rpm grinder ?

they don't offer very good performance if that was your intention, the more you go toward the center, the less abrasive is present and more fibre and adhesive, they sure can burn a 5 inch makita very rapidly...yeah been there and own the t-shirt too. i made my busching from mechanical tubing 5/8 id x 1.00 od and try to avoid doing it ...getting older and less daring