Fishmouth, AKA saddle for joining pipe by welding

The store bought hinged metal dohickeys for marking a square cut or a saddle cut on the end of a pipe cost about $16-$20 for each size pipe. Around here weldors use a cutting torch to cut the shape after marking the pipe with soapstone or...

I am so poor with a torch that this is a joke for me. I have tried and for me practice does NOT make perfect, practice makes frustration as I spoil more and more material.

Some folks use a jig on their drill press with hole saws. this works really good FOR THIN WALL TUBING. Heavy wall 2 3/8 pipe takes a long time to cut with a hole saw and you don't get so many cuts per blade.

I have a hydraulic press. I flatten the ends of the heavy wall tubing and can weld the flattened end to another pipe pretty easily. The thick walled pipe tends to crack where the radius of curvature is smallest when smashing them flat but when welding the joint I just make a quick pass over the crack and there is no problem.

I use this technique for welding "H" braces and corner fixtures for fences. Most of the stress on the joints is either compression or tension without much torsion or bending so the fact that this technique yields a weaker joint is of no concern whatsoever.

I have used this method to attach three pipes together in a compound triangle configuration with good success where a fish mouth or saddle would not have worked. Maybe one day someone will show me how to use a torch to cut a decent saddle. Until that skill is mastered, smashing the ends flat is working just fine.

I built a "gate brace" (see attachment). The gate brace as built is the "not darkened in) pipe. Wire tension of 5 strands of barbed wire puling in opposite directions bowed the vertical pipes. they are set in concrete and are burried over 3 ft in ground.

I pulled them back in shape with a "come along" and added the pipes depicted as darkened in. All joints in this fixture, original and added, are smashed pipe with no fishmouths (saddles). Looks OK works great.

I consider this technique " A Smashing Success" and if I didn't have a hydraulic press, I'd use my anvil and a sledge. My neighbor to the south has been helping me with our common fences and gates and also is no artist with a torch. He uses what he calls "gap rod" (steel scraps) to fill the ugly gaps in his saddle cuts while welding. His saddles are so poor he bought square tubing at considerable expense to build gates so he wouldn't have to cut saddles. He loves the results I got smashing the ends flat instead.

Maybe a cuting torch proof refractory material could be formed in the shape of a saddle and made to slip over the pipe to be saddle cut. Maybe then us ignorant savages could cut a decent saddle. Of course , now that asbestos is not used, what shoulld it be made of?

Hope this encourages the less skilled among us to fabricate with pipe even though they aren't an artiste with a cutting torch.

Pat

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hinged metal dohickeys for marking a square cut or a saddle cut on the end of a pipe

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Don't all welding supply houses sell those templates? I was with a neighbor once when he bought some of them. He wasn't the best I've seen with a cutting torch, but he was a darned sight better at it than I am. [img]/forums/images/icons/frown.gif[/img] He had to make some "H" braces to Corps of Engineers specs to put up some fence on Corp property that he had leased.

Bird, Yes indeady do, most welding supply vendors do sell the dohickeys. I bought one. Allows you to easily mark the perfect curve with a soapstone or new fangled "silver marker" but doesn't do squat to improve my abilitiy to cut along that PERFECT CURVE. If any thing, it increases my frustration at having spent $20 for a template that only highlights my failings.

You need a separate template for EACH pipe size. I, so far, have refused to accumulate a $100 + collection of devices to highlight my failures. Maybe it is just me but I have a REAL HARD time seing the soapstone line by the light of the torch while wearing the goggles. And even if I could see the line there is still the issue of my substandard cutting torch technique.

Pat

really no need to wear the dark goggles....all you are looking for is eye protection....clear lenses would work fine...I cut all day long with just safety glasses on....it really is pretty simple, you should be able to cut 15-20 per hour once you get set up!....

bigbukhntr, I find I need some shade for my eyes when I make a really bright glow in the process. Maybe over time through selective breeding welding families will develop a nicotating membrane that is darkened for welding.

Pat

if you really want to try something new...try the new helmets with the auto darkening lenses....it took me forever to get used to those things....I was forever flipping the hood up after I stopped welding...my welder would get such a kick out of watching me do that...then he's ask, why are you flipping the helmet up, just keep welding!...old habits are hard to breakIi guess...but now I wouldn't use the old style helmet if you paid me too... [img]/forums/images/icons/cool.gif[/img]

I have one of those by Hobart. It's auto darkening in 1/11,000th of one second and is adjustable darkness from level nine through level thirteen.

bigbukhntr, Yea verily, I have had a couple of those auto darkening helmets for several years. The first one cost plenty, the second was a gift. I have seen them in catalogs as low as $79. MIne have adjustable shade (9-13) and adjustable delay on the reverting to clear. I put the one I use on top of my roll around tool box and it became invisible. I looked for it a couple times and even had a friend look for it. Couldn't find it so I had to use the hand held thing that came with my Lincoln wire feed (MIG) then a few days later it became visible again and I got to use it again. Strange how things that would otherwise be in plain sight turn invisible for days at a time.

My training/habits are different. When welding at my neighbors with his "old fashioned" helmet with it flipped up I struck an arc and flashed myself a tad. I was so used to being able to see when not welding and not having to do anyting for eye protection before starting an arc that I just made an oops.

BUT YES YES YES the auto dakening with the larger size windows (to accomodate bifocal wearers) are WONDERFUL! A repetitive problem that I have is my breathing fogs the inside of the view port a lot and realy interferes with my vision. I actually hold my breath to weld under these conditions. I was thinking I might mount a fan like the solar powered ones on the pith helmets to try to keep it clear.

Pat