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Availbale Products, Material- and Service suppliers => Do It Yourself => Topic started by: PaulLowrance on February 18, 2009, 08:14:06 PM

Title: How to cut steel sheet metal
Post by: PaulLowrance on February 18, 2009, 08:14:06 PM
I have a roll of steel sheet metal that's 8inches by 10feet and 28gauge. I would like to cut the sheet metal in 8inch columns. Since steel doesn't bend so easily, then how is this cut? I don't want to saw it because that will lose a lot of metal. Will any of these work -->

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92148

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=65895

So on the electric one, lets say the blade is 0.5" long. Then after it makes one cut that is 0.5" long, then how am I going to push the cutter 0.5" into the steel sheet to cut the next 0.5"?  I mean, how is that going to happen without bending the sheet? Don't I need a long cutter? Also the sheet metal has a thin coating of paint, so I don't want to damage the paint.

Thanks,
PL
Title: Re: How to cut steel sheet metal
Post by: BEP on February 18, 2009, 08:39:15 PM
The nibbler is fine for most cuts except long or straight ones. Once you are done your hand will either fall off from wear or you will look like one of those crabs with one small and one large claw  ;D
If you are worried about waste from a wide cut the nibbler isn't the one for you.

The motorized shear is a good tool but I found Harbor freight products are usually one-time use  >:(

If your metal is 28 ga. then avoid bending it during cuts. Just let it flex out of the way when you cut and just use tin snips (hand shears).

The motorized shear works the same way. As you cut, one side of the cut flexes away as the cutter travels.
For sheet metal that thickness I just use hand tools.
Title: Re: How to cut steel sheet metal
Post by: Steven Dufresne on February 18, 2009, 09:33:01 PM
I've cut 24 gauge (0.025") copper and aluminium with tin snips. If your application is high voltage than you might also want to take into consideration whether your snips have serrated (teeth, and therefore jagged cut) or non-serrated (no teeth, smooth cut) cutting edges. A jagged edge will ionize air easier. That's something I'm careful of.

Is there any bending resulting from using a nibbler? I've never heard of them before you guys mentioned them. Often I start with a nice flat piece of metal and would like to end up with a flat piece too. You don't get that with snips.
-Steve
http://rimstar.org   http://wsminfo.org
Title: Re: How to cut steel sheet metal
Post by: Dave45 on February 18, 2009, 10:13:29 PM
Take it to a sheet metal shop get them to cut it with a shear.
Title: Re: How to cut steel sheet metal
Post by: PaulLowrance on February 19, 2009, 10:08:37 AM
BEP,

What you say sounds like great and true advice, but you're one funny guy! :-) So that's how a nibbler works. I was wondering. There must be at least two cutting blades to cut a channel, which would explain how it could easily slide through the cutting.

Tin snips? That seems familiar while strolling the isles of home depot. BTW, I agree with you on most harbor freight items. Some HF things are good such as their arc welding wire. I mean, how can you go wrong with that, 10 lbs of copper coated carbon steel 35mil for $20!!



Steven Dufresne,

Thanks for the info on snips. I'll look for some with no jagged teeth.


Quote from: Dave45Take it to a sheet metal shop get them to cut it with a shear.
That would be nice, but that's more of a luxury option for a flat broke guy like myself!



PL
Title: Re: How to cut steel sheet metal
Post by: Bulbz on February 19, 2009, 10:51:41 AM
When my brother-in-law used to work as a steel fabriactor, I used to sometimes visit the factory. I noticed they used some sort of hydraulic guillotine to cut sheet metal of various thickness. Maybe there's a similar buisiness near you, that could do it. I'm not sure how much metal is lost during cutting though.
Title: Re: How to cut steel sheet metal
Post by: PaulLowrance on February 19, 2009, 03:50:53 PM
Is this it?

http://swallowfield.typepad.com/photos/uncategorized/2008/05/22/board_shears.jpg

PL
Title: Re: How to cut steel sheet metal
Post by: PaulLowrance on February 19, 2009, 05:11:17 PM
Wish I had one of these -->

http://www.youtube.com/watch?v=z1AezUhkqO0

I still don't know the difference between a nibbler and shears. Which one wastes the least amount of metal?

PL
Title: Re: How to cut steel sheet metal
Post by: PhiScience on February 19, 2009, 05:22:01 PM
Hi PL,

28-Guage that’s 0.0149”
I have installed many windows and used that same stuff for capping.
All I use is a straight edge and a razor knife.

Clamp your straight edge into position, score the metal a few times with your knife, remove the straight edge, fold your metal and it should separate very easily.
Perfect cut every time.

Wayne
Title: Re: How to cut steel sheet metal
Post by: Craigy on February 19, 2009, 06:22:28 PM
Quote from: Dave45 on February 18, 2009, 10:13:29 PM
Take it to a sheet metal shop get them to cut it with a shear.

Seems the best way to me,  and something a workshop could do in 15 mins well , rather than you spending a whole saturday doing it getting blunt snips and sore hands
Title: Re: How to cut steel sheet metal
Post by: PaulLowrance on February 19, 2009, 06:32:17 PM
Thanks Wayne. It's hard to believe that would work, but I'll give it a try.  :)

PL
Title: Re: How to cut steel sheet metal
Post by: Bulbz on February 19, 2009, 06:34:50 PM
Quote from: PaulLowrance on February 19, 2009, 03:50:53 PM
Is this it?

http://swallowfield.typepad.com/photos/uncategorized/2008/05/22/board_shears.jpg

PL


Yeah, one of them looked like that, and the other one was powered by hydraulics or something like that.
Title: Re: How to cut steel sheet metal
Post by: Bulbz on February 19, 2009, 06:47:09 PM
Quote from: PaulLowrance on February 19, 2009, 05:11:17 PM
Wish I had one of these -->

http://www.youtube.com/watch?v=z1AezUhkqO0

I want one !  ;D
Title: Re: How to cut steel sheet metal
Post by: infringer on February 20, 2009, 10:35:21 PM
Dangerous hard to get but... still possible if done properly and I am not 100% sure it would be clean but most likely there is a way to make a clean cut with thermite ...

But yes a metal shop is cheap there is a local metal shop backwoods type just about anywhere I go anyways...

The nibbler does work fairly well used it to cut out squares...

Well appears that most of the bases are already covered unless you have some wild way to super pressurize water for a water jet :P

There is many ways I could go on but the likely ways are the ways that are the cheapest ... you either buy a tool or pay just as much to have it done... 6 of one half dozen of another!

Result = money lost

Title: Re: How to cut steel sheet metal
Post by: maynard013 on February 21, 2009, 06:43:14 AM
Hello there. How about a grinder and a zip cut blade. Just a thought. Google walter zip cut blades. This way you can also de-burr the edges. Razor sharp steel isnt a good thing. Wear gloves no matter how you cut it. The best way to cut it would be a plasma cutter but $$$$
Title: Re: How to cut steel sheet metal
Post by: jadaro2600 on February 21, 2009, 02:33:11 PM
Quote from: PhiScience on February 19, 2009, 05:22:01 PM
Hi PL,

28-Guage that’s 0.0149”
I have installed many windows and used that same stuff for capping.
All I use is a straight edge and a razor knife.

Clamp your straight edge into position, score the metal a few times with your knife, remove the straight edge, fold your metal and it should separate very easily.
Perfect cut every time.

Wayne


...best advice yet.

Use a straight edge and a razor ...score multiple times, and move the score inline with the edge of the table and press down evenly across the entire length of the piece.   The score should break easily if you've pressed down evenly during the cut.  You could wind up going through a few razors for this.

-James
Title: Re: How to cut steel sheet metal
Post by: capthook on February 23, 2009, 02:51:01 AM
A jigsaw with a metal-cutting blade works well and quickly.

I recently made numerous complicated cuts out of 16 gauge, so 28 gauge would be a breeze.

Then smooth out the cuts with a hand file. (slightly raised edges)
Title: Re: How to cut steel sheet metal
Post by: PaulLowrance on February 23, 2009, 07:23:34 PM
Thanks for the replies. In this case, the bending of the steel is probably not a good idea since there's a very important thin coating of paint on the steel that cannot be damaged. Another reason is that the steel will be layered together to form a laminated transformer, so the entire piece of steel must be perfectly flat.

I'll buy the following metal shear cutter from Harbor Freight for $35 -->
http://www.overunity.com/index.php?action=post;topic=6858.10;num_replies=16

If I wasn't so broke I'd buy a good one at Home Depot, but they sell for hundreds of dollars. Anyhow, this particular shear cutter design seems to be appropriate for my application. Here's a video of the same type of shear cutter, different manufacturer -->

Skip to 1 minute & 35 seconds into the video:
http://www.youtube.com/watch?v=5cvyCZTDXqg

This type of shear cutter does not remove material, just cuts, and there's no burrs and such.

Thanks,
PL
Title: Re: How to cut steel sheet metal
Post by: infringer on February 28, 2009, 07:15:44 PM
Looks nice so do all commercials...

Attention to detail and cut shots should make you wonder though look at the shamwow commercial and excellent example when he says one shot will not cut away you will notice the amount of cola and pay attention on the rug sample....

All commercials have one goal in mind to impress you enough to buy there product...

Let me know how the product really functions when you get it!
Title: Re: How to cut steel sheet metal
Post by: PaulLowrance on March 01, 2009, 10:37:18 AM
Both Harbor Freight stores were out of them. Maybe they're popular because that shamwow guy can sure sell a product, lol.  ;D

PL