Thread: Colorbond and Irwin Metal Saw Blade

Yes, take it back. Must be something wrong with it. Colourbond is just corrogated iron with paint on it. Nothing like as tough as stainless. But why didn't you use an angle grinder with a metal cutting disc ? ($1.50 at Bunnies).

Dean

There is a thread on here regarding tearing colorbond iron across it and it does work. When you cut iron with saws or cutting discs you set it up to rust. This is a notice that the manufacturers usually supply with the iron. Sounds like your Irwin purchase was indeed faulty and perhaps returning will be in order.

Regards Mike

Thanks. Well I have this cold cut Ozito metal cutting saw you see so it is much quicker and easier to use than a grinder. Gives nice straight cut too.
But yes I will take this back and get a refund. The manufacturer does not recommend use of grinder but saws circular saw with metal blade is ok to use. I did read all the other threads about it here but nothing specific to say that colorbond will chew up a metal circular saw blade after just a few cuts.

Back to bunnies I go. They will probably want to give me a new blade, but I'll insist on a refund because I think the new blade will just do exactly the same! Might try and get a nibbler as a replacement instead. I should add that I have finished the cutting with the blade (only 5 sheets) but I should certainly expect the blade to last a heck of a lot longer than that for $90!

The only thing I can think of is, does the recommended blade speed match then saw speed?
I would take it back regardless of this anyway, I think they will give you a refund.
Nibblers are very slow and spit little shavings everywhere, so you have been warned,lol

As for using a grinder with a cutting it will burn away any of the sheets protection in that area and let it start rusting, that is why they brought out these type of saws.
I have used them myself over the years, but it is not recommended by the manufacturers and can void any warranty.

Dave

Originally Posted by Dave J

The only thing I can think of is, does the recommended blade speed match then saw speed?
I would take it back regardless of this anyway, I think they will give you a refund.
Nibblers are very slow and spit little shavings everywhere, so you have been warned,lol

As for using a grinder with a cutting it will burn away any of the sheets protection in that area and let it start rusting, that is why they brought out these type of saws.
I have used them myself over the years, but it is not recommended by the manufacturers and can void any warranty.

Dave

Hey Dave. Saw blade rated to 4500 RPM max, saw spins blades at 3500 max so well within spec there. Yeah the nibbler I will think again about. This was the other option if for some reason they wouldn't refund me in full. Thanks for all replies. The damage looks like the blade has been htting concrete or something very hard, but I checked the saw for marks inside and out and nothing, and I certainly did not run it into anything but the roof sheeting.

I'm with what Dave says about most nibbles. Slow and a half moon shavings that are about 1mm wide in the middle and taper to nothing either end. You'll spend longer cleaning them up than cutting.

The biggest problem with grinding colorbond(or zinclume) it the grinding dust. When it gets on colorbond is sticks to the paint then rusts leaving rust lines that look bad but dont do much damage. If it gets on zincalume, as there is so little zinc it is quickly used up and the sheet will start to rust. This applies to swarf from drilling as well.
I've found you can cut colorbond in a stack with a grinder, but you have to wash each sheet well afterwards.

Stuart

When we built our house I worked with the roof plumber (can't be trusted to your own in Vic, but that's another story)

He cut the sheets by hand with a tin snip.

I suggested we use my air shear, like this one

BRAND NEW Metal Shear with Pistol Grip -Air Shears Tool (eBay item 200565931900 end time 15-Feb-11 15:57:02 AEDST) : Home

He was most impressed.

It does a great job, not too noisy, nice clean and straight cuts.

Originally Posted by Big Shed

When we built our house I worked with the roof plumber (can't be trusted to your own in Vic, but that's another story)

He cut the sheets by hand with a tin snip.

I suggested we use my air shear, like this one

BRAND NEW Metal Shear with Pistol Grip -Air Shears Tool (eBay item 200565931900 end time 15-Feb-11 15:57:02 AEDST) : Home

He was most impressed.

It does a great job, not too noisy, nice clean and straight cuts.

I have some air shears but they dont go over the ridges at all easily

I had the missus go to Bunnings just before with the blade. They got the tool guy over apparently and he said he had not seen anything like that. He looked at it and found the "Made in China" mark and gave us a full refund. I think they also realised a $90 small metal cutting cutting circular saw blade shouldn't shed half its teeth in 5 cuts on thin steel

Congrats to Bunnings for at least acknowledging a defective product without making a big problem over it and offering a full refund.

nice to see they paid up have a look at this thread for next time https://www.woodworkforums.com/f18/ti...rr-iron-32039/

I had a builder build the room on the left in the photo. My involvement with him ground to a halt when quoted me 97 bucks a square meter to supply and install the roof sheeting. I had built the room on the right a few years earlier and resheeted the old roof at the same time. I wasn't a stranger to how unappealing the job is to do, especially on your own.

I cut the hips with a pair of offset Gilbows. The valleys were cut with a thin disc in a 5 inch Makita. Every sheet I marked in place then climbed down onto the ground to cut. Cleaned up all the exposed edges with a file and even dressed the ridge capping down into the corrugations.

I shied away from the saw because I thought that the pushing the saw across the sheets covered in swarf would stuff the zincalume up. (does it?)

A pair of air shears would have made a prick of a job a bit more tolerable.

Anything would be easier than the way I did it.

67 bucks with free postage!
I'll be stuffed. I would have paid more for the Gilbows .