For all you guys who struggle with notch cuts......

[Yummi]

This contains a handy little tool that could be used to make notches pretty easy.  About at the :20 sec mark. 

I say every garage should have one....

#Winner!


http://www.youtube.com/watch?v=oc-QRpAQOp0&feature=related

[fabr]

+1!! Probably only costs a few bux.

[Engineer]

I will go down to harbor freight and grab one.




Actually I think these get a pretty good result at .0001 times the cost.

[fastcorvairs]

I will go down to harbor freight and grab one.




Actually I think these get a pretty good result at .0001 times the cost.

I have two of these.  One in for 1.00 inch and  one is 1.5 inc.  I'll make some one a screaming deal on them. 

[fabr]

You don't like them either,huh?

[Hammerworks]

Years ago,(about ten now)I designed(when I say designed I mean an extremely elaborate sketch) a tube notcher that would work in a similar way.Except my design used an everyday handheld plasma torch,to make it available for the home builder that already had a plasma cutter.It had two stepper motors,one to rotate the torch(instead of the tube,like in that video)and one to feed the torch in and out along the tube axis.The tube diameter was set manually by the clamp holding the torch.The device attached to the edge of a bench and the tube layed on the bench extending out into the cutting area.There was two settings on the machine ,one for mating tube diameter and one for angle of cut.This way the tube could be fixtured for length/clocking to the bench.I have a friend who owns an automation company that agreed to write the control software if I built the prototype mechanics.Well....I never did.

This idea stemed from my original idea of having a set of collars,with the notch profile on them, that fit over  the tube and guided it under a plasma while you turn the tube by hand.....nope never built that one either.

[fabr]

Interested in maybe discussing making it a reality?

[Engineer]

Cutting the notch right never seems to be my problem....

Knowing the exact length, angle and twist of the notch are the problem since you can't get the tube in place until it is notched.

You would think that the hundreds of thousands of dollars worth of software and equipment shown in the video would fix the problem but I don't think it does because unless your always landing dead tubes you still have to weld the tube underneath in many cases.

[Reidy02]

Actually Torchmate offer that sort of thing too cause I was gonna buy it when I bought my CNC table till I saw the price I must admit I'm still tempeted though...

[BDKW1]

Man Craig really makes a lot of companys look good. All the CAD work you see there is done By Craig Hall at R&I industries. They also do the laser tube notching and sheetmetal for many in the industry.
 
Some more good fab porn.....
 

 

 

 

[LiveWire]

I started playing with the two angle notches. Some people call them chop saw notches, but I have a 48"x6" belt sander that I can take them down quickly with after cutting them off straight. I wrote an Excel spreadsheet that I put on my Android smart phone. I enter the tube sizes and the intersection angle and gives me the grind angles. I want to put some calculations in it next for rotation of the tube. If you have a compound angle, you don't need a fixture to dial in both angle in because it still is a single angle to the tube, just rotated. I want to enter both angles and have it give me a single intersection angle to notch too as well as the degrees of rotation of the tube.

I have a 4 axis mini mill with stepper motors. I paid like $3500 for it. I would sell it for $2500. The steppers are not strong, but would easily move a plasma torch head around. I bought it for prototyping, but was disappointed in the feed rate I could run a 3/8" end mill through 3/16" aluminum.

[brycter]

OH MY!!!! i need to take a breath that is sweet!!

[Yummi]

I started playing with the two angle notches. Some people call them chop saw notches, but I have a 48"x6" belt sander that I can take them down quickly with after cutting them off straight. I wrote an Excel spreadsheet that I put on my Android smart phone. I enter the tube sizes and the intersection angle and gives me the grind angles. I want to put some calculations in it next for rotation of the tube. If you have a compound angle, you don't need a fixture to dial in both angle in because it still is a single angle to the tube, just rotated. I want to enter both angles and have it give me a single intersection angle to notch too as well as the degrees of rotation of the tube.

I have a 4 axis mini mill with stepper motors. I paid like $3500 for it. I would sell it for $2500. The steppers are not strong, but would easily move a plasma torch head around. I bought it for prototyping, but was disappointed in the feed rate I could run a 3/8" end mill through 3/16" aluminum.

Yea, that made sense to me. 

I have a check book for my angle / axis / stepper / notch / uh thinga magigiggy needs.   If it helps i am "disappointed in the feed rate" for the check book as well. 

[fastcorvairs]

Yea, that made sense to me. 

I have a check book for my angle / axis / stepper / notch / uh thinga magigiggy needs.   If it helps i am "disappointed in the feed rate" for the check book as well.

Yummi
Your waaaaaaaaaaaaaaay over worked.  You need to slooooooooow dowwwwwwwwwwwwwwwn and smell the flowers. 

[LiveWire]

You can make a notch by cutting two angles off the end of the tube. Take two paper towel tubes. Flatten one and cut a point with two 45 degree angle cuts, it will roughly fit to the other tube. With thin metal and not squishing the tube, it fits nearly perfect. Once you start tilting the intersection and using thicker wall tubing, it gets more complicated. The inside edge of the tubing is what hits first. If you try 45 degrees with .120 wall tubing, you find the inside at the points hit and don't let the tube go on all the way. So you have use less than 45 degrees. My spreadsheet makes all the calculations. The first time I tried it on real material, the notch fit very well. So well in fact, that I doubt I will ever use hole saws again. Just for one set of A-arms I make, I have 16 notch fixtures (4 arms -> 8 tubes -> 16 ends) that mount on the lathe quick change tool post. I will probably throw all that out and make new ones based on either the belt sander or a mini chop saw.

The short version of the feedback comment is the thing can't cut fast without bogging out. A plasma cutter is just moved. It does not require pressure like a saw or end mill.