IR air saw blade options for thicker steel?

[Greg72]

Just picked up an IR air saw (model 429 IIRC). It came with a small assortment of 24tpi and 36tpi blades.

Those seem to be fine for thin, clean sheetmetal cuts but I was wondering if there is a coarser blade that might allow me to cut 1/8" or larger steel plate. I've searched a bit online, but 24tpi seems to be the coarsest blade they make.

Depending on how well it worked it could cut brackets much closer to the final dimensions I need and spend less time doing all the finish work on the 20" grinding disc. Free handing cuts with the plasma cutter leaves a substantial amount of extra material that needs cleaning up.

Just brainstorming to come up with a faster way to get my parts built.



-G

 

[4X4HIGH]

Might want to see if it uses the same blades as a jigsaw because I know you can get alot of different TPI blades for those but to be honest those air saws aren't meant for cutting thicker stuff like you're wanting to do they're meant for shett metal.

 

[Greg72]

Yeah it uses a 1/2" blade that tapers down to maybe 1/4" in the cutting area so that it can make sharp turns. I can find quite a few blades that are 1/2" thick along their entire dimension with very low tooth counts which would be good for cutting metal, but wouldn't turn very well.

I think I came across a 14/18 tooth blade by IR that might work, but it's not rated for non-ferrous metals so it might end up dull in a real hurry.

I will get plenty of use out of the new saw for sheetmetal work, but if there was a way to do thick cuts too I'd be able to make use of it right away. As you can probably tell I'm getting really fired up about the steady forward progress of my build lately, so I want to find ways to make the most out of my shop time.


-G

 

[blazinzuk]

I have used those plenty. Cheap ones and good ones. Not built for thicker steel. At all. I tried several different blades in mine.

Worked better when I cut stuff with my jig saw

I though have taken to cutting some fancier brackets out with a jig saw shaping them and that to guide the plasma cutter. Some its just not worth the time though because of the fact that you have to undersize the bracket

 

[rdn2blazer]

When you band saw cut are you cutting right on the line? You shouldn't have to disc grind much at all, just clean up the saw cut finish with a light disc grind to remove, debur the edges and your done. You did say plasma cut though so that takes more time and work to clean up. WHat grit discs are you using? I use mainly 36 grit, those cut FAST! Watch your fingers with a new disc! My 20" with a new disc in the only machine tool that actually makes me REALLY be extra careful when using. I'm always careful, but a new 36 grit disc is a flesh remover in a hurry.

 

[Greg72]

Rob,

Was your question for me?

I use the 36-grit that you recommended way back when. It does move metal, but when I'm working on a 1/4" thick plate with a long straight section against the disc, it really slows things down considerably. Sometimes I'll angle the part and cut a strong bevel into the top and bottom edge to get me closer to the target line...then I lay the part flat and work it again. That helps reduce the amount of material that needs to be moved (basically only the center 1/3 remains to be moved to the final dimension).

The plasma is great when I have a straightedge cut. I can get really close to the final dimension, but as you probably know the plasma always cuts with a slight angle through the steel, so you need to stay a little off the line if you want the finished part to have a perfect 90* edge. And of course on curved parts that I'm free handing, I keep really far off the line so I don't accidentally twitch and booger up the edge. I use silver Sharpie markers when I'm marking for plasma cuts, but even that isn't always easy to see with my shades on. Maybe there's a better option that has stronger visual contrast.

Ultimately, I should just drop the $5K on a beautiful Torchmate CNC 4x2 plasma table and really increase my production speed....


-G

 

[rdn2blazer]

Rob,

Was your question for me?

I use the 36-grit that you recommended way back when. It does move metal, but when I'm working on a 1/4" thick plate with a long straight section against the disc, it really slows things down considerably. Sometimes I'll angle the part and cut a strong bevel into the top and bottom edge to get me closer to the target line...then I lay the part flat and work it again. That helps reduce the amount of material that needs to be moved (basically only the center 1/3 remains to be moved to the final dimension).

The plasma is great when I have a straightedge cut. I can get really close to the final dimension, but as you probably know the plasma always cuts with a slight angle through the steel, so you need to stay a little off the line if you want the finished part to have a perfect 90* edge. And of course on curved parts that I'm free handing, I keep really far off the line so I don't accidentally twitch and booger up the edge. I use silver Sharpie markers when I'm marking for plasma cuts, but even that isn't always easy to see with my shades on. Maybe there's a better option that has stronger visual contrast.

Ultimately, I should just drop the $5K on a beautiful Torchmate CNC 4x2 plasma table and really increase my production speed....


-G

Yes my Q was ment for you Greg. I don't have a plasma, want one but don't have one yet. I forgot about them angle cutting slightly through material. I guess I'm just so used to using a vertical band saw and cutting right on the line or outside the line but right against it, it taked nothing to grind to clean up the saw tooth cut finish. Band saws are easier to follow a straight or curved line then free hand plasma cutting I would assume. Do you have a band saw? It may be "slower" then cutting with a plasma, but if the detail prep is faster it's a wash in the end. Pros for the band saw are no hot sparks to catch something on fire and ALOT less post prep.

 

[Greg72]

I'd love a band saw,, but the cheap ones are for wood cutting not steel. Every time I tried to find one for steel the prices seemed to be about 5x higher....

I did score a sweet deal on that Apex grinder, so if you want to throw me some brands / models to search for on Craigslist, I'd consider adding one to the stable. Space is getting a bit tight, but I could probably make it fit somehow.


-G

 

[rdn2blazer]

This little POS cuts steel all day long for me. It's a crappy...probably HF band saw but I use good blades. It's has it's capacity limitation but it's dirt cheap and everyone who has them loves them cause if they break you scrap it and go buy another one. Everyone says they beat the snot out of theirs, me included and it keeps on running though. Just a thought. I would LOVE a bigger vertical band saw and I WILL have one someday, but for now this does the job. Hell it's even got a seat to sit down on when you cut stuff

 

[4X4HIGH]

Hell it's even got a seat to sit down on when you cut stuff

HaHa Rob, I used to have one of those and I also sat on it while I was cutting material. I gave that saw to Greg but apparently he got rid of it.

 

[blazinzuk]

I have one of those little band saws too.

They work alright.

And Greg yes probably should just invest in a torchmate!

They sell the small 2x4 one for not a bad price only like 4k if I remember