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L4 into trees
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I'm just wondering if anyone has any experience notching tubing with a plasma cutter? Is it feasible? Is the quality as good as with a hole saw notcher? Any tricks or techniques? Jigs? Thanks.
 

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If you have the $ to buy a plasma cutter, buy a notcher from Harbor Freight. They're pretty cheap.

Problem with the plasms is you'll still have more work getting the joint perfect than with a hole saw unit.

http://da.harborfreight.com/cpisearch/web/search.do?keyword=tubing+notcher&Submit=Go

There are more expensive units out there, but if you're making a few cages, that might be the ticket.

We have one and it works great.

John
 

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slow is slow....
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I've seen guys notch with a crop saw really well....but plasma cutter? You'd be better off having beavers gnaw on the end of the tubes!

Andrew
 

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I agree that doing a standard fishmouth with a plasma cutter is pretty questionable, but it can be handy for fitting a tube into another multi-tube joint (particularly when it involves angles that you can't approach with an "ol-joint-jigger"-style notcher). You can use a contour fitting tool (like these: http://www.pipemastertools.com/ ) to get the pattern, and make the initial cut with a plasma cutter - but I find that there's still a good amount of grinding necessary afterwards.

I did witness a nice CNC plasma tubing notcher setup at a sport aircraft facility in northern Colorado once - the machine simply rotated the tube, and moved a plasma cutting torch (held above the tube in a bracket) longitudinally along the axis of the tube. Seemed to work pretty well.

--
Kevin Wenzel
[email protected]
 

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don't cut
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Phlyan Pan said:
I'm just wondering if anyone has any experience notching tubing with a plasma cutter? Is it feasible? Is the quality as good as with a hole saw notcher? Any tricks or techniques? Jigs? Thanks.

If you have a good plasma cutter, and it's perfectly setup for the specific material, and you are an experienced operator, then I guess a plasma cutter would work. In reality, they usually don't make cuts that are of sufficient quality to finish weld without some grinding or smoothing. I've seen the professional CNC setups do a good job, but that requires a ton of setup, and the quality of the machines is usually far about the standard found in a garage shop.

A better way is to use a "joint jigger" style hole saw tool. Good ones cost about $150, and work well. We tried a Harbor Freight one this summer and it lasted about 3/4 of a roll cage before it started to fall apart. Maybe okay if you never do one again, but I prefer to spend more and have decent tool than to waste time screwing around with a POS.

I've also done shallow angle cuts with a sawzall or cut-off wheel, and then a bench grinder. Sometimes I'll take a dressing tool and round the wheel on the grinder in order to better form radiuses on the tube. This makes the wheel useless for anything else, but their cheap. I'll warn you though (and this goes back to your question about the plasma cutter), any time I try to "freehand" a cut like this, I spend 3x the time making the joint, vs. using the jigger. Sometimes it's inevitable, but I wouldn't want to do an entire car this way.

DEM
 

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Loose nut behind the wheel
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I have a bender and notcher from Pro Tools. I have had them both over ten years. The models have been updated and improved.

http://www.pro-tools.com/index.html

I have been very happy with both items I have.
 

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I've rough cut with plasma and then went on to finish up with either a bench grinder or a 4 1/2" grinder.

Patience is really the key to any method you use.(although if you do use a notcher, a good bimetal holesaw, a rigid setup, and a drill that you can actually run at the correct speed are fairly important)

I think there is a dos or windows program called "miter.exe" which allows a person to print out a template on paper that wraps around the tube. It's popular with bicycle building people. The downside is that you actually have to know what angle you want to cut beforehand....
 

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Use a proper tool. If you want to use a Plasma cutter, you may as well use a oxy/acetylene torch--way too much "clean-up" for either.
 

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If I had unlimited funds I would invest in this:

http://www.mittlerbros.com/Tube_Notcher_Ultimate.htm

I find making a smooth and consistent cut with hand-held plasma difficult enough in a straight line on a flat surface. I can only imagine how pathetic it would look trying to circumnavigate a tube! But for door "X"'s where the tubes join I would probably use it....in the past its been the chop-saw and grinder technique and it takes forever.
 

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I've used a plasma cutter in the past on a tough notch but the clean up isn't worth it. You have to grind it anyway to get rid of the plasma cut anyway as the plasma edge affects the weld quality.

On a tough cope, use a toilet paper roll to get the fit close, cut it with a sawzall then slowly grind to fit. I usually use a short section before grinding on the final tube.

There's a great tutorial over on the Pirate 4x4 on the chop saw method. Works well, but not as good as a quality notcher. I bought a JMR unit about 8 or 9 cages ago and haven't looked back!
 

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Making some fence panels out of 16 gauge (0.065") or 15 gauge (0.072") 1-5/8" steel tubing. There will be need to make about 1,100 90º joints. let say a tubing notcher, but it could be very time consuming and could get expensive buying holesaw bits.
 

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Does he understand what issues he's seeing?

Air pressure and flow, travel speed, and distance between the tip and work piece all factor in.

On thinner sheet dragged cuts on mine are really very good if I don't cock up and go too fast.
 

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Making some fence panels out of 16 gauge (0.065") or 15 gauge (0.072") 1-5/8" steel tubing. There will be need to make about 1,100 90º joints. let say a tubing notcher, but it could be very time consuming and could get expensive buying holesaw bits.

How did you end up doing these?

I would have used a holesaw on a good arbor in a mill with a quickvise and depth stop.
 
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