Coping steel pipe prior to welding.

[McMXi]

I have a big welding project this spring in the form of a steel pipe "pole barn". I have lots of pipe on hand for the trusses and have two ways to go. One is to cope the pipes to fit up at the various angles required, and the other is to notch and insert plates at the joints. The Moline airport has some very nice examples of this approach (see below).

If I go with coped joints I'm thinking of using SolidWorks to model pipe that has an I.D. equivalent to the O.D. of the pipe that I'll be using. I can cut the pipe at the appropriate angle, split the pipe in the model, and then 3D print the two halves of the pipe and use it as a template to mark the pipe in preparation for cutting with plasma.

Is there a better approach to figuring out and cutting coped joints in pipe? When I worked as a welder many years ago we'd cut out a pipe until the joint looked good, wrap a piece of paper around the cut, mark the cut and then reuse the paper to mark the rest of the pipe that we needed. It was good enough at the time but there might be a better way now.

 

[North Idaho Wolfman]

I really like the way they did those trusses as they are really strong and quick to build.
Makes alignement super easy.

I'll have to dig a little deeper in my search history as I had one picked out for a drill press too.

https://www.amazon.com/Industrial-Professional-Pipe-Tube-Notcher/dp/B077WP3VLZ/ref=asc_df_B077WP3VLZ?mcid=0efb5012a62033d5b7c0cf524daf7277&hvocijid=6798602576048765530-B077WP3VLZ-&hvexpln=73&tag=hyprod-20&linkCode=df0&hvadid=721245378154&hvpos=&hvnetw=g&hvrand=6798602576048765530&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9029659&hvtargid=pla-2281435179978&psc=1

I have Annular cutters for my drill press.
Talk about drilling sweet holes fast!

other option:

 

[McMXi]

I really like the way they did those trusses as they are really strong and quick to build.
Makes alignement super easy.

I'll have to dig a little deeper in my search history as I had one picked out for a drill press too.

https://www.amazon.com/Industrial-Professional-Pipe-Tube-Notcher/dp/B077WP3VLZ/ref=asc_df_B077WP3VLZ?mcid=0efb5012a62033d5b7c0cf524daf7277&hvocijid=6798602576048765530-B077WP3VLZ-&hvexpln=73&tag=hyprod-20&linkCode=df0&hvadid=721245378154&hvpos=&hvnetw=g&hvrand=6798602576048765530&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9029659&hvtargid=pla-2281435179978&psc=1

other option:

That Centurialinc coping tool looks like it could work well for me. The only downside is the need to reset it over and over. Hmmm ... decisions, decisions.

Tube & Pipe Notching Tracers, Get the perfect notch first try! — Centurial Inc

This tool makes tube fabrication a breeze! Three steps and your done. Center the tool in the tube joint, and press the pins to fit the contour of the notch. Slide the tool over a new tube, that needs notching. Then use the marker to trace the profile. That's it! Notch the tubing and clean up the

www.centurialinc.com

 

[North Idaho Wolfman]

I edited my first post, and added a little.

 

[McMXi]

I edited my first post, and added a little.

I have a Hougen mag drill with two sets of those annular cutters and yep, they're the bees knees. I'd rather use plasma to cut the steel pipe given how long and heavy the sections are. I'm going to look at how many different coped joints I'll need to make, and will decide if one of those pin type coping tools is the way to go.

 

[Lil Foot]

My fence contractor used one of these, and then torch cut the pipe, cleaned it up with a large cone shaped grinding wheel.

https://www.amazon.com/Mercer-Industries-730020-Marking-Cutting/dp/B01NAOA9SL/ref=asc_df_B01NAOA9SL?mcid=0e66a6fc628b3f1ea68f07c951d7ef59&hvocijid=4738606864790083379-B01NAOA9SL-&hvexpln=73&tag=hyprod-20&linkCode=df0&hvadid=721245378154&hvpos=&hvnetw=g&hvrand=4738606864790083379&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9192591&hvtargid=pla-2281435178858&th=1

Whoops, we couldn't find that.

 

[North Idaho Wolfman]

Aww yes plasma, that would be much quicker.
If you could make a jig to follow that would make cuts quick and accurately.

Hey a jig like Lil foot put up might work perfectly.

 

[McMXi]

My fence contractor used one of these, and then torch cut the pipe, cleaned it up with a large cone shaped grinding wheel.

https://www.amazon.com/Mercer-Industries-730020-Marking-Cutting/dp/B01NAOA9SL/ref=asc_df_B01NAOA9SL?mcid=0e66a6fc628b3f1ea68f07c951d7ef59&hvocijid=4738606864790083379-B01NAOA9SL-&hvexpln=73&tag=hyprod-20&linkCode=df0&hvadid=721245378154&hvpos=&hvnetw=g&hvrand=4738606864790083379&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9192591&hvtargid=pla-2281435178858&th=1

https://www.grainger.com/product/1P...Sd_NLZ3qyIjgRHyBqq3dAfD2qpRPXzahoCxesQAvD_BwE

I'll have to check the angles in the trusses that I had designed, but that could be the ticket right there.

 

[Lil Foot]

My fence contractor said when he builds the gates (at his home shop) he cuts them with a plasma cutter, (no clean up with grinder needed) but at the job site he marks them with welding chalk, then torches them.
Our local ACE carries that clamshell marking jig.

 

[Runs With Scissors]

I have no experience with building stuff like that, but it seems to me that the "notch and insert" appears to be a more "user friendly" way.

Seems like it lends itself better to terms like "over a scosh". or "up a tad".

 

[McMXi]

I have no experience with building stuff like that, but it seems to me that the "notch and insert" appears to be a more "user friendly" way.

Seems like it lends itself better to terms like "over a scosh". or "up tad".

I agree and it's why I've take a lot of photos of the trusses at the airport in Moline. I've seen similar truss work at other airports. However, there's added expense and/or work making plates and cutting notches for the plates to sit in. For now I'm leaning towards what I have experience with along with my ability to use a tape measure.

Talking of trusses, back in 1992/93 when my wife and I were living in Portland, OR I worked as a certified welder for a steel erecting company. Portland was in the early stages of upgrading building standards to meet newer earthquake related standards.

Apple was expanding rapidly and had an injection molding facility that was way too small so we had the contract to add a lot of capacity. A concrete contractor poured the slab, and then poured "tilt up" panels on the pad and this is where our work began. We had to raise the concrete panels and I had to weld H-beams around the inner perimeter to steel inserts in the panels. We finished up by installing and welding the steel trusses that were made elsewhere.

Where this story gets interesting is that once the job ended I was out of work, but a couple of days later had a job at a fabrication shop that did all manner of welding projects. The new owner was an a$$ and after a few months I'd had enough. A rudder pin from a Navy destroyer kept coming in and I kept telling the owner that some Navy engineers need to come and inspect the pin as I was grinding and welding on it to rebuild the keyway. He wouldn't listen, and by the fourth time the pin came back (failed inspection), and he told me I had to work all weekend to get it done, I told him where he could stuff my job.

I got home that afternoon and there was a phone message from the steel erecting company asking me if I was available to go back to the building we'd put up for Apple since the engineers/architects hadn't accounted for the weight of the injection molds when designing the trusses. They allowed for the weight of the gantry crane, but those molds were huge and very heavy.

I spent six weeks at that building as Apple was in full production making computer monitors. A bunch of blue prints were dropped off along with a lot of steel and 7018 welding rods. I had to work four nights when working above a machine. Apple would allow me to weld above the injection molding machines but only during the night shift. They had three shifts going. That was a fun job welding in lots of plate into the web and onto the flanges of the trusses.

 

[PoTreeBoy]

I have no experience with building stuff like that, but it seems to me that the "notch and insert" appears to be a more "user friendly" way.

Seems like it lends itself better to terms like "over a scosh". or "up a tad".

I agree, the plate clip and notched tube will save time. All the welding can be done flat; welding around pipes is tough for a rookie like me. One downside is it leaves lots of open ends to attract dirt daubers, etc.

I've only 'notched' tubing by hand and for right angles, but that drill notcher and annular bits looks attractive to me. But I don't own a torch or plasma, either.

 

[North Idaho Wolfman]

What are you top and bottom cords going to be made of?

 

[Russell King]

See this video for making your own 3D printed coping guides. I think he has the software available and you can just download the files to a site for printing.

I was looking for a video where the guy draws it out on paper using some points (descriptive geometry) but he starts with the pipe in position and then wraps paper around the pipe to start the process. I will keep looking for that but the video above gets you a more durable template.

 

[McMXi]

What are you top and bottom cords going to be made of?

The entire truss will be 2" steel pipe.

 

[McMXi]

See this video for making your own 3D printed coping guides. I think he has the software available and you can just download the files to a site for printing.

I was looking for a video where the guy draws it out on paper using some points (descriptive geometry) but he starts with the pipe in position and then wraps paper around the pipe to start the process. I will keep looking for that but the video above gets you a more durable template.

Thanks very much for that. I have a Bambu Lab 3D printer at the house so could easily print up some coping guides.

 

[GreensvilleJay]

FWIW....
My 'vote' is for the KISS system, Notch and plates. EASY to fab, EASY to align, EASY to weld . It's also FAST !

 

[McMXi]

FWIW....
My 'vote' is for the KISS system, Notch and plates. EASY to fab, EASY to align, EASY to weld . It's also FAST !

The approach shown above with plates, angle and pipes is much better suited to trusses that use angle for the top and bottom cords and pipe for the webs. Since I'm using all pipe, coping the joints is the best way to go as far as I'm concerned. If I had a bunch of suitable angle laying around I would absolutely copy the design of the trusses at Moline Airport.

 

[GreensvilleJay]

FWIW The '50s Freeman loader on my #1 tractor is 2 and 3" round pipe with gussets.
The 'problem' I see with coping is you need a real good tape measure and precise cutting/welding techniques, proper cuts, welding jigs, time.
Nowadays anyone can buy the equipment,hopefully know how to use it to save time,material.
Curious, do you have to have an engineer 'sign off' on the trusses to pass local building codes ?

 

[PoTreeBoy]

The approach shown above with plates, angle and pipes is much better suited to trusses that use angle for the top and bottom cords and pipe for the webs. Since I'm using all pipe, coping the joints is the best way to go as far as I'm concerned. If I had a bunch of suitable angle laying around I would absolutely copy the design of the trusses at Moline Airport.

Welding those clips to the pipe should be straightforward, but you seem to have a lot of experience with coping so go for it.

There is another possibility, you could flatten the ends of the web members, cut them to length and angle, then weld each side to the chord. The fancy way of doing this requires a die, though.

The connection method you choose should be considered by the truss designer.