Pictures of My Homemade Porty III

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YUKON 659

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I just wanted to post a couple of pictures of a Port A Wrap I started today. I will get the welding done tomorrow and post a finished picture. I made the tube out of 1 3/4", 1/4" wall stainless steel tubing. The rest of it is made from 1/2" stainless. The only dimension that I knew for sure was the small porty had a 1 1/2" diameter tube and the large one was 2"...I made mine in between!!! Can anyone tell me what diameter the "cleats" are on a factory Porty? I should be close.

Jeff
 
I remember seeing a home made Port a Wrap II at a safety seminar..it came in two pieces, as it failed under load at or near a weld.

Sorry to p1ss on your chips, but a home made lowering device - especially if it involves home welding - is not a good idea. Those components look great, but the welding will probably let it down. Even if that's A1, and you've not trapped slag in there somewhere, the process will weaken the parent metal, unless you can compensate with many hours of strictly controlled heat treatment.

You will never know what it's true safe working load is - you may find it's breaking load!! - so how can you ever trust it?
 
I agree with Acer up to a point.
The flip side is that someone had to weld the first prototype other wise we would never have "it" in the first place.
My big concern with fabricating my own stuff is the time and money and energy it takes.
When you are copying a proven design the payback is even less.
If you figure your time alone, not including the cost of materials, costs of fabrication, costs of designing, in makng your home made porty I think you will find it is a losing idea.
But hey maybe the next thing you make will be what everybody will want next year. Look at Greg Goods device. That device is so far ahead of the competion I am always puzzeled why anybody would buy anything else. but then again folks still buy polyester leisure suits...
Frans
 
Or climb on Arborplex.

Flinch factor is the problem with the GRCS. It takes practical app for most people to be won over.

Look at Dan Murphy, he's sold on it, but still has not bought ;)

I bought mine after working with a guy with one, and whishing I had one with other companies.
 
Originally posted by Frans

My big concern with fabricating my own stuff is the time and money and energy it takes.

When you are copying a proven design the payback is even less.

If you figure your time alone, not including the cost of materials, costs of fabrication, costs of designing, in makng your home made porty I think you will find it is a losing idea.


For me, metal fabrication is a very satisfying hobby. The most useful item is the log dolly ( looks somewhat like the one in the Sherrill catalog ) that I am working on!
 
Originally posted by rich hoffman
The most useful item is the log dolly ( looks somewhat like the one in the Sherrill catalog ) that I am working on!

This is a different case..in fact I'm thinking of making something similar myself. You won't know how strong it is until it breaks in service, but what happens then? The log might fall 6" to 1' to the ground, and you'll have to spend the rest of the day carrying out the logs the hard way. With home made rigging devices, of which you probably won't know the true strength, or a truly safe load to take it up to, the consequences of a failure under load are pretty serious. I wouldn't trust home welding in that situation, unless you can put it through the correct heat treatment afterwards.

My 2p
 
Acer and others, I understand your concern about the issue of the homemade porty being safe. It is also a concern of mine. I have been a toolmaker for 23yrs. working and building products out of metal throughout this time. I do agree with you the weld will probably break before the stainless gives out but I would dare say that the weld on this port a wrap is better and stronger than any "production" weld job on a factory bought one. It was done by our toolroom welder, not me. I also talked with a guy who does testing on material to see why or if it will fail when used in a production atmosphere and he seemed very confident with the design and weld job. The tensile strenghth of 1/2 inch stainless steel, even after a "worse case" heating, bending and welding job is still 98,000 lbs. of tensile strenghth. I will use this port a wrap.....I will also be very carefull not to overload it. I don't see any reason why this device will not be able to handle at least 1,000 lbs.

Jeff

P.S. I will post finished pictures later...its done I just haven't had time to take pictures yet.
 
SIZE MATTERS , is everyone so bent on being the "one " they have to come up with stupid reditions of every thing , what's next the figure 7 belay device , in the words of Penn & teller , "That's Bull???? !"
 
Jeff,

You've obviously done your homework. I've seen things that people have cobbled together in the back garden out of scrap metal with their hobby MIG set - those are the sort of things I wouldn't trust under load.

The design will work well - I bought one from sherrill's when I visited a friend in MT, and it's quick and easy to set up. I can't fault it.
 
What is better then a figure 8? everything else. The GRCS is the best thing available except for a crain.\
Too much rope on rope friction on an 8, it is only a step above a munter or 3 wraps on the tree. Infact for most things, anything is better then 3wraps. All 3wraps is good for is a good laugh.
 
I made all three of the port-a-wraps I have used. I would rope out pine and oak blocks that were 1 ½’ x 8’ using ¾” double braid with no problem. I used two of them at one time to lay 60’ pine stubs down when a client wanted 20’ lengths. I had to lay them down that long because 20’ logs could not be dropped out. I trust my welding but then I have been doing it since I was 12. Not sure I would want to try to make one like the new design though. It does not seem to be a lot of area for the weld. I do plan on ordering one from Sherrill.
 
Originally posted by Tim Gardner
I trust my welding but then I have been doing it since I was 12.

The failed port a wrap I saw had been welded badly. But even if your welding is good, a home welder cannot avoid the effect of the heat affected zone. As the work cools down in air, the mechanical properties of the parent metal change, and this often leaves a brittle zone close to the weld. So even if your weld is spot on, you may have weakened the parent metal..that's why in manufacturing companies, fabrications will go through a heat treatment process to anneal the work and eliminate stresses due to welding, followed by controlled cooling to give the desired physical properties, something that could only be done in a kiln with temperature control.

If you know what you're doing, and are allowing for all this, then fine. If you're not sure, then don't put home made items in safety critical situations.
 
Norm and Scot would just shake their heads and say "don't try to seu me when it breaks. ( that actualy happend to Scott, they got the papers and he had his lawyers get the device to look at it, It was not his design and it was modified, poorly.)

They did not patent it because they did not want the headaches.

On that line, Denny Morehouse says he kcicks himself for not getting a patent on the first figure 8.
 
speaking of making your own tools.
I have been wanting a metal stake side wagon to haul brush loads from the backyard to the chipper.
NorthernTool.com has a few ready made but no brakes.
I used one made by Don Blair but he does'nt make them anymore.
It was real slick you could rotate the pull handle and dump the load.
I hauled massive loads of brush with the thing.
You could stack loads of branches 10'-15' long with the ends dragging and just fly out of the yard with them. It had a brake so It would'nt walk away while you were loading it. And it had metal rods as the stakes so you would thread the stakes down through the load and into the stake holes.
worked real good
 
My choice would be stainless steel....it's stronger and if it's 300 series it will not rust. Stainless is a little harder to machine but overall it's a much better choice. Unfortunatley it's a little heavier and also more expensive.

Acer, when you refer to eliminating stress in kiln to relieve stress, the process is actually refered to as stress relieving. Anealling is a process to draw back the hardness after a hardening process. When stainless is welded there is no hardening taking place...and as far as the stress it would be very minimal. If you were to weld some type of air hardening tool steel (A-2, A-8, D-2 etc.) there would be a little hardening around the weld and yes it would be a good idea to fully anneal the piece.

Jeff
 
Has anyone tried using 303 stainless? It machines and welds nicer than 302 or 304. If you wanted to get real fancy, you could use some 304V, but that's pretty expensive in comparison.
 

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