Making Perfect Pipe Saddle Cuts With a Bandsaw or Chopsaw

Intro: Making Perfect Pipe Saddle Cuts With a Bandsaw or Chopsaw

True "experts" of a trade know those little "simple tricks" that make a job much easier. This is one of those tricks that makes working with pipe MUCH easier. I learned this wonderful way of making saddle cuts years ago, but only recently learned very few people know about this. So, I thought I would share. I know the first time it was shown to me, I said "That's amazing!" I can only hope your feel the same!
All you need to make wonderful looking and fitting saddle cuts is a bandsaw or chop saw.

I've made a video for this, and it's the last step. I think it's a bit easier to understand than photos. 

STEP 1: Setting Up for the Cut

I'm gonna show all this being done on a bandsaw, only because it is much easier to photograph.  A chop saw or  cold cut saw  works just as well.
First, set the saw to 35 degrees.  This does not have to be exact.  33 to 37 degrees should work, it will just change how much is cut off.
Get some scrap pipe, and set the pipe in the saw.  Then adjust the length to be cut off.  The cut will NOT be made in the center of the pipe, in this example, the blade is about 3/16 of an inch from center.   One could use math to figure out the offset, but it doesn't take too many cuts to begin understanding how cutting off more or less of the pipe affects the saddle.    But for now, don't worry about where you make the cut. 
Once the pipe is tight in the vise, I use a C-clamp as a stop.  When the pipe is turned half a rotation, the clamp will ensure the same length of cut is being made.   On every chop saw I've used, it's impossible to use a C-clamp, so I use a sliding square, and measure in from the end of the vise.  However, when the pipe is turned,  the square will be in the cut.  If precision is not needed, just eyeball across the end of the pipe to the end of the straight edge.  Or, lay a strap iron across the end of the pipe.  A bit more complicated and time consuming...

STEP 2: Turn and Cut Again

Now, rotate the pipe half a turn, and cut again.  With 35 degree cuts, there should be a "flat spot" between the two cuts, not a point.  The width of the flat spot depends on the angle of cut, and the size of the pipe.

STEP 3: A Saddle, and Two Vicious Pieces

After the second cut is done, that's it!  You will have a wonderful saddle cut, and two vicious pieces of metal.  I say that because these cut offs will go right through a shoe, or tire, air hose, extension cord....basically anything you don't want them ruining. Make sure they get put in the scrap barrel immediately!

If one cuts too MUCH off the pipe, (end up with a bigger scrap piece) the result is a "pointy" cut.  This point will hit the pipe being saddled, and create a gap.  If it's not too bad, a quick touch up with a grinder will correct it.

If one cuts too LITTLE off the pipe, (small scrap), the result is a wide flat spot that does not touch the saddled pipe.  Sometimes this is acceptable, depending on the welding process, and use of the pipe.

But, what if the pipe is NOT of the same diameter?  Well, on to the next step!

STEP 4: Larger Pipe Saddled to Smaller Pipe

35 degrees work great for pipe of the same diameter, but saddles are often done on various size pipe.

If the pipe being cut fits over the pipe being saddled, then set the saw to 45 degrees.
Set the blade to cut on the center of the pipe.
Turn, and cut again, just like before, except the pipe will be pointed.
It will fit right around the smaller pipe!

I've showed you the basics, but this idea can be expanded upon. This works for non 90 degree saddles, too. Cut one side 30 degrees and the other 45 degrees, and see how it saddles.

STEP 5: The Video for Making Saddle Cuts

Sometimes, a video is the easiest way to explain things.  So, I made a video!  

Comments

[beth15]

i need to fit two piece of 8" pipe together at a 45 degree. forming a lowercase y. any suggestions?

[countryoldmate]

Can you provide the brand and product name of your protractor templater?

[Metalworker extraordinaire]

it's a great way to join metal tube, I have been doing it this way for years. I've got a chart giving joints between many different size tubes, it's so simple

[nlstockstill]

You wouldn’t happen to be able to share such a chart would you?

[lindekugeljustin]

Did i miss the quick and simple step?"

[Christianv108]

My workrest has a rib under also, so I get a chunk of short 2x4 which is taller than the underside of the rest which allows me to position my C-clamp farther out.

[Christianv108]

The tip for doing the reverse end using a chunk of angle and chalk is very useful. Thanks.

[ForgetMyProfile]

Cant tell you how many hours I've spent trying to drill a hole in the mating pipe and cutting it in half.

or taking a grinder and making a perfect (ha ha) half-round to articulate with the other pipe.

One question . . . do you personally use the saw to back bevel the pipes when you cut the angles, therefore making the cuts sharper on the exterior, narrower on the inside to them fit even better?

Really GREAT IDEA. Thanks,

Robb
Grand Rapids, Michigan

[Metalworker extraordinaire]

use a grinder to do thar

[samson3000]

I'm not completely sure I understand your question.  Just 2 cuts are made, and if the angles are correct, the fit will be correct as well.     Does that help answer your question?

[ForgetMyProfile]

No,  you didn't answer my question. Probably poorly framed on my part.

It looks like you have made your cuts at   90 degree angle to the pipe. I would think that if you set the saw angle so that the the angles were "undercut" meaning that there ends up being a bevel on the pipe cuts, you would have an even tighter joint at the connection.

If I could, I'd send you a sketch to show you what I mean. Maybe this  crazy drawing will help  ;


                                        outside of pipe
PIPE  cut  on an angle  _ /                                  rather than  |_
                                        Inside of pipe

Why am I asking this? Cause I'm a lousy welder with a cheap as heck rig. I need all the advantages I can get.

Robb, Michigan

[tmedlin]

You don't want a perfectly angled fit up on the pipes. You should cut it at 90 degrees and the bevel that is left allows penetration for the weld. It creates a natural bevel; otherwise there would be less penetration.
Tim

[samson3000]

I spent some time messing with this over the weekend, and couldn't come up with a way to create a beveled cut.  All the ways I tried only made for dreadful fitting saddles.  If you figure out how to set up the saw to do such, let me know, as there are times when it would be useful. 

[Goedjn]

I don't think you can do it with a bandsaw. The other side of the pipe would
get in the way.

[stitch 2 u]

looks like a pretty tight saddle will it work for a 14" trunk and 8" branch

[Metalworker extraordinaire]

yep

[Poppy_Ann]

i make many saddle cuts in aluminium tube up to 3 inch and i  just usa a hole cutter/saw.
the easy way is to set the drill in the center of the hole saw just before the end of the tube then cut through the hole saw neads to be the same size as the tube you want to conect to not the size of the tube you are cutting ie if you are wanting to join a 1 inch tube to a 2 inch tube then use a 2 inch hole sawthat way you get perfect jointsif you want to have the joint at an angle then just drill through at the required angle. very easy to do.

[richardde]

A hole saw would work good on Aluminium since it is soft and easy to cut, you wouldn't want to use a chop saw on aluminium.

[Poppy_Ann]

Yes I was making new rails for my sail boat out of aluminium and due to the wind blowing away the gas for the MIG set I wanted the best fit available to reduce the amount of welding to fill the gaps i first tried to use a grinder to shape the cut out but was always getting to many gaps to try and fill in but then had the brainwave of using a hole saw which worked out great it cut the time of creating a connection from around 30 minutes to just 2 or 3 and the result was so much better than before i went back and replaced all the ones I had done by just cutting out a 90 degree cut and grinding to (semi) fit, if you are working on steel then just get a HSS hole cutter if you want the best fit do not try and use the cheap type of hole saw that has lots of different blades that fit into grooves and are held in by a screw they are only good for soft wood and only a couple of cuts at that.

Regards Poppy Ann.

[gkendall]

Just made my upcoming projects a little easier. .got any tips for coping small pipe to larger pipe...say 4" to 6"