Tools for Coping Angle

Hello Everyone

I have been welding a little angle for various projects. Most of the pieces are relatively short and I have been making the cuts on my mill. It is a little more time consuming but, to say the least, the results are very accurate joints.

What do yall use?

Thanks

Grits

I would use either my bandsaw, iron worker, cutting torch, cut off disc in a grinder.
Material type, size and quantity would dictate which one.

Scott

Banksaw

Thanks Scott

My band saw is a horizontal model. Even thought it can be used upright, I do not find it very practical.

I have used a cutoff wheel in a grinder in thinner stuff with good results. I use a plasma cutter also. for one or two pieces, I can do it in a mill before I get the plasma set up.

Grits

Cutting torch and a side grinder.

Plain old saw does a very good job if you know how to use it.




With known tube size and joint angle, tube can be notched with great accuracy. The notch is achieved by cutting two opposing angles on one end of a piece of tube, to form a point. The cross-section of this cut will be an elliptical cut due to the shape of the tube. Changes in both of the two angled cuts must be made for the intersection angle and the size of the two tubes being joined. The only real limitation is the max angle of the chop saw.
You start with what I call the base angle. This is the angle of both cuts if the joint was 90[FONT=&quot]°[/FONT]. For an example, I am fitting two tubes together that are both 1.75", at an 90[FONT=&quot]°[/FONT] joint. The base angle or the angle of both cuts is 28[FONT=&quot]°[/FONT]. These two cuts must meet at a point, and the point must also be centered on the tube.
What if I want a 15[FONT=&quot]°[/FONT] joint with my 1.75" tube???? You must start with your base angle, witch was 28[FONT=&quot]°[/FONT] for 1.75"(remember above), and subtract 15[FONT=&quot]°[/FONT] from one cut, and add 15[FONT=&quot]°[/FONT] to the other cut to form a perfect notch. So now I must make a 13[FONT=&quot]°[/FONT] cut and an 43[FONT=&quot]°[/FONT] cut , with the point centered on the tube. Perfect coped joint, with no grinding.
Remember your base angle will change with the tube being cut and the tube that you are fitting to.
Here are a few examples of base angles...
2.0" to 2.0" tube, base angle of 30 [FONT=&quot]°[/FONT]
1.75" to 1.75" tube, base angle of 28[FONT=&quot]°[/FONT]
1.5" to 1.5" tube, base angle of 26[FONT=&quot]°[/FONT]
1.25" to 1.25" tube, base angle of 22.5[FONT=&quot]°[/FONT]
1" to 1" tube, Base angle of 20[FONT=&quot]°[/FONT]
Now to fit different size tubes together
1.75" to 2" tube, base angle of 25[FONT=&quot]°[/FONT]
1.75" to 1.25" tube, base angle of 45[FONT=&quot]°[/FONT]
1.25" to 1.75 tube, base angle of 20[FONT=&quot]°[/FONT]
1" to 2" tube, base angle of 12[FONT=&quot]°[/FONT]


Ed

Good Work

Thanks Ed.

The cuts look good. Never thought about it that way.

Grits

a quicker way to calculate the angles for notching tubing is to go here http://snip.awardspace.com/

i have a roper and whitney contraption that shears, notches and bends angle iron.
http://roperwhitney.com/bending/2-1617.cfm

Angle Iron

Hello Everyone

I am coping angle iron; however, I want to hear your comments on tubing also. I normally notch tubing on my milling machine with a hole cutter.

I have been coping angle iron on my mill just due to convenience. It probably takes a little longer but it comes out perfect the first time.

Ecortech, What kind of a bandsaw are you using?

Grits

Bandsaw is a horizontal 7x12 bought at Princess Auto, our equivalent of your Harbour Freight. Saw is quite well built for the price, have not had any problems with it at all.

Ed

Yabut...the saw in the pic is mine...lol! Good to see someone using the "101 Tube notching" thread (From HSM).
That saw is a Busy Bee (yes Don..I know) 4X6 swivel head saw. Handiest contraption there is for this kind of work.
For right angles like that I use my ironworker/pipe notcher now. Unreal quick!
Russ

Surprised, nobody's mentioned or thrown a 'port-a-band' into the mix.

On some projects I would be a bit handicapped/hindered without the use of a
Milwaukee deep-cut bandsaw.

coping

I used to use a hole saw but found that a jig on my rotary table works better. The rotary table gives me a tight fit which comes in handy when I am welding stainless steel.

rusty ripple said:

a quicker way to calculate the angles for notching tubing is to go here http://snip.awardspace.com/

Click to expand...

Awesome link, Thanks rusty.

I made a vise to attach to a lathe to notch tubing when I need to do it with an end mill - more rigid than a Bridgeport. I also made one to clamp in a mill vise when I has to be done on a bridgeport. I can take photos if you need to see.

Mud said:

Awesome link, Thanks rusty.

I made a vise to attach to a lathe to notch tubing when I need to do it with an end mill - more rigid than a Bridgeport. I also made one to clamp in a mill vise when I has to be done on a bridgeport. I can take photos if you need to see.

Click to expand...

Wouldn't mind seeing pics of both.

I nearly always use a bandsaw for coping angle. If I have more than an inch or so of tab to cut off after making a cross or angled cut with the bandsaw, I often use the plasma cutter followed with a quick cleanup grind with an angle grinder.

If you have to cope an angle at say 35°30' (35.5 degrees) then it would take a very long time on a mill. I use the protractor head on my combination square and, in a good light and wearing 2X lenses, carefully set the head angle. Then I use the combo square to set the fixed jaw on the cutoff bandsaw. I get good angular accuracy that way. I use a gentle downfeed and watch like a hawk for any sign of the saw cut going off square.

Grant

Torker sorry I couldn't remember where I had got that info from, my saw is the same god awful yellow, but 7x12. I have so many pics saved on my computer just assumed because of the color, it was a pic of my saw, but you are right they are both your pics and the info was originally posted by you on HSM. I had been shown how to do this many years ago by an oldtimer who has now left us, it is my preferred way to miter tube. Your write up is the very good easy to understand, most people I try to explain this to just look at me like I'm on another planet, good job. When I show them your write up the lights come back on.

Ed

Grits, if you are just coping angle iron, then the fits generally do not need to be so precise unless you are TIG welding angle iron??? Anyway, the really fast way is the ironworker shear - you can set most any angle with an angle finder, if you don't have one then the old abrasive chop saw works really well, fast, easy, accurate enough.

Coping tubing is another story. I have and still use all of the following:
Abrasive saw, mill with a hole saw, vertical band saw, horizontal band saw, Burr King belt sander, lathe with a milling cutter in the spindle and tube on the toolpost. I do not have a mechanical notching tool (the shear type that clips off a nice little cope of one side of the tube), but have used one...works well for 90 degree copes of the size tool you have. I do not have one of the belt sander copers, nor do I ever want to use one...I'm sure I'll have to buy one immediately! There are advantages to each, and some times it is best to use a combination of a couple of methods...for example a long cope. If one tube is intersecting another at a 30 degree angle, the cope is pretty long. I would start with the chop saw to remove a big chunk of the material as it is really fast, then probably to the lathe with a long roughing end mill in the spindle, dial in the angle and clean up the cope, check fit, recut if necessary. The advantage of the milling cutter (or the belt sander coper) is the ability to rotate the tube slightly to get the rotation correct...you just cannot do it with a hole saw if needing to remove only a slight amount of material. The band saws work well too, but the horizontal is really only good if you are not in too big of a hurry, but it is pretty burr free.

As is typical, you will find the best method through some experience and the toys you have at hand.

Steve

Thanks Steve

I am, for the most part, a hobbyist. Normally, I may have to cope three or four pieces of angle. I have been using my BP because it is there and set up is minimal with a DRO. The results are usually prefect. I have a couple of projects on the horizon that will involve coping quite a few long pieces of 2"x1/4" angle. A vertical band-saw would be an easy solution as would a Porta Band.

Thanks again for all your comments.

Grits

I just finished making a tubing notcher using a end mill. Just machined an arbor thats 1.25 and if i need a smaler end mill i made bushings. I found a cheep 90 degree gear reduction and motor last year at metal meet. Works great very similer to the one mitler brothers sell for $3000. I need to take a pic and maby post later

Great info from everybody more then one way to skin a cat

Jason