# Cutting large I beam with recip saw, which blade?



## Dave in Pa (Oct 10, 2009)

Warren said:


> We added footers and will be installing steel posts. As for the scrap portion, it will be 37" long and should weigh about 150 pounds or so. I will probably use a ratchet strap to keep it in place until the cuts are completed.


Thanks! Be safe, and do it correct! Looks like ya are going in the correct direction here!


----------



## superseal (Feb 4, 2009)

My welding supplier carries super thin 4" metal blades, the name I can't remember. I do know they're Garnet colored and ridiculously thin. They slice and dice steel angle irons rather quickly and I've squirreled through many I-beams as well. 

With my gutterwork, they barely leave a bur in aluminum and they hold up surprisingly well. 

Finish up the rest of the cut using your sawzall with Milwaukee bi-metal blades. Keep them lubed with cutting oil and you'll be glad you did.


----------



## Pearce Services (Nov 21, 2005)

superseal said:


> My welding supplier carries super thin 4" metal blades, the name I can't remember. I do know they're Garnet colored and ridiculously thin. They slice and dice steel angle irons rather quickly and I've squirreled through many I-beams as well.
> 
> With my gutterwork, they barely leave a bur in aluminum and they hold up surprisingly well.
> 
> Finish up the rest of the cut using your sawzall with Milwaukee bi-metal blades. Keep them lubed with cutting oil and you'll be glad you did.


Sait?


----------



## superseal (Feb 4, 2009)

Pearce Services said:


> Sait?


You got it...1/16" thick, like these guys...worth every penny!
http://www.jimslimstools.com/Produc...igh-Speed-Cut-Off-Wheels---Type-1__23061.aspx


----------



## superseal (Feb 4, 2009)

Because they're so thin, remember to bush out the 4" grinder so you don't bust them up.


----------



## sunkist (Apr 27, 2012)

duburban said:


> lenox gold
> 
> would an oil make sense in this case?


a cutting lube is a good idea, i like a product called cut ease it a solid product in a tube used all the time machine shops


----------



## Chris Johnson (Apr 19, 2007)

No room for a torch in there?


----------



## Warren (Feb 19, 2005)

sunkist said:


> a cutting lube is a good idea, i like a product called cut ease it a solid product in a tube used all the time machine shops


I am gonna finish these cuts tomorrow. I wont be able to venture all over looking for specific cutting discs and cutting lube. Can I just use regular grease or another type of oil? 

Man, I sound like such a noob.
Worst case scenario, we will just battle through with a dozen or so sawzall blades of different varieties.


----------



## Warren (Feb 19, 2005)

Chris Johnson said:


> No room for a torch in there?


A torch would certainly work in qualified hands. I had a guy working for me for a couple of years who used to be a welder. Back then, I would have asked him about this and he may have suggested bringing in a his torch. 

I don't own one, and would not let any current employee, or myself use one.


----------



## superseal (Feb 4, 2009)

Just squirt it with WD or fluid film or what ever general lubricant you have - keep your blades cools and cut down the speed on the sawzall.

Your shoulders are gonna hurt like hell if your overhead since this ain't a fast process, but I'm sure you'll pull through.

Better yet, just have your helper do it :thumbup:


----------



## dom-mas (Nov 26, 2011)

Those zip cut blades are sold at just about any building centre I've been to


----------



## Warren (Feb 19, 2005)

superseal said:


> Just squirt it with WD or fluid film or what ever general lubricant you have - keep your blades cools and cut down the speed on the sawzall.
> 
> Your shoulders are gonna hurt like hell if your overhead since this ain't a fast process, but I'm sure you'll pull through.
> 
> Better yet, just have your helper do it :thumbup:


I am sure that this will require the "expertise" of the low guy. I am also sure that I will be doing something much more important at the exact time that the beam is being cut.:thumbsup:


----------



## mako1 (Sep 1, 2013)

illbuildit.dd said:


> Lenox has always been my favorite. I think you're gonna burn a bunch up no matter what. Sometimes those mean pruning blades cut great but dull really fast


 Always liked the Lenox blades myself.I buy them at Fastenal and get a pretty good break on quantities.


----------



## CarpenterSFO (Dec 12, 2012)

superseal said:


> Just squirt it with WD or fluid film or what ever general lubricant you have - keep your blades cools and cut down the speed on the sawzall.
> 
> Your shoulders are gonna hurt like hell if your overhead since this ain't a fast process, but I'm sure you'll pull through.
> 
> Better yet, just have your helper do it :thumbup:


I realize it won't get used in this case, but some dark cutting oil will double or triple your speed through mild steel. The sulfur and other additives make a big difference compared to plain lubricating oils.


----------



## Tinstaafl (Jan 6, 2008)

Warren said:


> A torch would certainly work in qualified hands.


That's the first thing that occurred to me when I saw the OP, but I figured you were ruling that out due to flammability concerns in this particular situation. Between labor and consumables, you're probably going to spend at least as much money and a heckuva lot more time than if you'd just had a good welder do the cuts. :sad:


----------



## tjbnwi (Feb 24, 2009)

Shaped charge;

http://en.wikipedia.org/wiki/Shaped_charge

Tom


----------



## SouthonBeach (Oct 18, 2012)

If I didn't have a torch. I would use a 4" grinder with a thin cutting blade, then finish up with the sawzall if needed.


----------



## mski (Apr 4, 2013)

Warren said:


> A torch would certainly work in qualified hands. I had a guy working for me for a couple of years who used to be a welder. Back then, I would have asked him about this and he may have suggested bringing in a his torch.
> 
> I don't own one, and would not let any current employee, or myself use one.


With your time spent cutting the beam, money in blades, disks or whatever wont it be easier hiring someone to torch it?


----------



## griz (Nov 26, 2009)

tjbnwi said:


> Shaped charge;
> 
> http://en.wikipedia.org/wiki/Shaped_charge
> 
> Tom


They're a framing crew not a SOG....:whistling


----------



## Calidecks (Nov 19, 2011)

Can you drill a series of holes first?


----------

