Pics Of homemade lowering device

[mic687]

My ground guy is a metal fabricator by day so he and I put this togather in his shop. No idea of the weight rating but we built it heavy. base is 8"x2.5"x
.25" channel with a pice of 3/8 wall 3.5" pipe 7.5 " long with a piece of .5"steel rod 7.75 "long for a tie off. Side plates are 8"x8"x.25 steel plate. On mine one side plate is shorter but if I did it again I would make both sides
8x8x.25. On the left plate we welded a flat bed rachet and on the right is a strap hook hole. We strap this to the tree with a 20,000lb strap. We only use
this on take downs because it will damage the tree trunk. We are working on something to use as a back cusion for pruning large limbs.

 

[tomtrees58]

oke:get a hobbs dont be cheap i have 2 of them tom trees

 

[mic687]

The one I really want is the grcs I like the Harken winch they use on it. I don't have the 2400.00 yet, that pesky insurance cost and such.

 

[treesquirrel]

That hinge is going to be your weak link IMO. You shock load that thing with a hinge pin that looks like about 5/16 inch diameter you best hope it holds and does not shear off.

Personally I'd get rid of the hinge.

Also keep in mind that in the event of an incident that results in personal injury the device that fails will be under scrutiny.

While it looks cool and is probably pretty strong I'd rather cough up some cash for a certified and thoroughly engineered and tested device. There is a palce for home grown but my .02 is that this is not one of those places.

no offense intended, please be CAREFUL!

 

[mic687]

The hinge is 9/16" rod. No offense taken we have not used this devidce on any really big loads. Although we did use it on the cottonwood I posted eariler. I understand the concern and appreciate it. My fabricator is pretty knowledgable and has not steered me wrong yet. That said I am not endorsing this device nor recommending anyone build one I was asked to post some pics and so I did. Again thankyou for the input and concern.

 

[Tree Pig]

Yeah I had mentioned it in your earlier post and thanks for posting it. Always good to see others ideas. Unit looks solid my only question is wouldnt it work better with the mounting device at the top so that all the weight and the strap would hold the working end more secure to the tree. I could be way off but it looks like all that weight would make it sag forward a little and not give you a straight shot up the tree. Either way nice piece of homemade hardware.

After another look the top eyes for a second strap to secure top?

 

[mic687]

Sthil, top eyes are for fiddle block attachment.:greenchainsaw:

 

[lees trees]

good job

I'd use it. your fab guy did a great job. since the hinge is 9/16 even a mild steel will handle most take downs.

 

[newb]

Mic, Look for some blown tire retreads that are on the side of highways all the time. If you fasten that to the back of your device it will save the bark on big trims. Pete

 

[mic687]

Pete, Thats kind of what we were thinking with the rubber backing. I will say
the tire tread had not occured to me thanks. For now we are using a Port A Wrap.
mic

 

[John Paul Sanborn]

I do not like how the flanges of the beam will contact the tree, it does not seem like there will be enough surface contact for such low friction surface.

The tube of the bollard comes out pretty far, have you done any math on the forces applied and the strength of your weld?

For moderate rigging I would have no reservations using it. It is a step up from a protawrap, since you get the sling play out of the equation. That is, it would be a lot easier to pull slack.

 

[mic687]

John, we had to do a re engineer on the device due to some slippage. This is the second generation and it works much better. We had to increase the length of the base plate. The advantage of this set up is when strapped down it is solid, when you take a wrap it gives a solid base to work from. I used this on the cottonwood I posted pics of and did the mods after the first day. After mods it has preformed great. So far I have used it on Norway pine, White pine, Ash, Maple and Red oak with no slippage. That said we are still developing this and will continue to test it in a controlled setting. I have not loaded this device super heavy most take downs I do the space constraints will not allow it. For general everyday use no extreme loads it preforms great. I only use it for take downs due to the dammage it does to the tree base

 

[treemandan]

Nice looking work but without a ratcheting bollard it really has no advantage over a Port-a-Wrap.

The rigid anchor is one difference and I think its pretty cool too. No matter what it gets put on its going to leave a mark so perhaps make a draw bar so you can fit it into a receiver tube.
Also welding a tab on the back that fits into a saw kerf isn't a bad idea. The c-channel will bite pretty good but possibly the channel should be boxed. I have something simular and if you use a fiddle you should be allright.

 

[treemandan]

I do not like how the flanges of the beam will contact the tree, it does not seem like there will be enough surface contact for such low friction surface.

The tube of the bollard comes out pretty far, have you done any math on the forces applied and the strength of your weld?

For moderate rigging I would have no reservations using it. It is a step up from a protawrap, since you get the sling play out of the equation. That is, it would be a lot easier to pull slack.

Yes, it should be boxed I think. With repetitve use the c-channel has a tendency to bend.

 

[Ax-man]

Wow, talk about a blast from the past. That looks very similar to my first homemade lowering device. Instead of the hinge for the strap I made mine with some eyes so we could fasten it with a 3/8ths Hi-test chain and used a chain binder to fasten it to tree trunk.

It was kind of a clumsy affair but it worked good at the time that I used it.

This was before Porta-Wraps made an appearance on the rigging scene. After we got Port-Wraps my homemade lowering device didn't go out much unless we had a really big tree.

Looks good to me. I was concerned about my welding also but we tested it to the limit and the darn thing held fast and secure.

I'll never forget the first time I used mine on a practice tree in front of our house. My son who was maybe 10 years old at the time was able to lower out big limbs and large chunks of wood with that device. He thought that was so cool to be able to do that by himself.

Of course me the old man was watching everything like a hawk making sure all was safe and secure from the bucket. I thought it was pretty cool myself as we made a step forward in rigging as I could see the advantage immediately using a bollard verses wrapping the rope around the main stem of the tree.

Larry

 

[crashagn]

My ground guy is a metal fabricator by day so he and I put this togather in his shop. No idea of the weight rating but we built it heavy. base is 8"x2.5"x
.25" channel with a pice of 3/8 wall 3.5" pipe 7.5 " long with a piece of .5"steel rod 7.75 "long for a tie off. Side plates are 8"x8"x.25 steel plate. On mine one side plate is shorter but if I did it again I would make both sides
8x8x.25. On the left plate we welded a flat bed rachet and on the right is a strap hook hole. We strap this to the tree with a 20,000lb strap. We only use
this on take downs because it will damage the tree trunk. We are working on something to use as a back cusion for pruning large limbs.

Picture IMG_0165.jpg In my own opinion i think it would be safe for small takedowns. Anything with alot of weight- main trunks and such i wouldnt use it. I can only imagine the repeated shock load tweakin them hinge pins and softening them up over time. I personaly would use heavier pins and also thicker plate steel for the winch and especially the right attachment point. It does look good though.

 

[plowboy]

my hats off to your groundy . most groundys I've known just lift a job the week before were they were saying would like fries with that . keep him around he thanking

 

[outofmytree]

Looks like a good 2nd generation unit mic.

I have a couple of questions and a couple of suggestions.

Can you post a picture of the hand crank/winch in its working position with a length of rope in place please. I have some thoughts about rope path but a picture would really help.

Has the manufacturer got certification for structural welding? If so then this goes toward covering your proverbials should there be a failure. If not then have another made but welded together by someone who has that certification.

I am equally concerned about the hinges. Any moving part that has lateral force applied especially a serious shock load, can potentially fail. If this is to be used only on removals then cutting a shallow kerf as you see done in GRCS demonstrations would increase the stability of the device under shock load and eliminate the need for hinges assuming they are to allow for variation in trunk diameter.

Congratulations on having the cojones to show pictures of a home made device on this forum.

 

[Ellistrees]

I think it impressive enough that I might copy it.

Got be little cheaper than the port-a-wraps.
I've often wanted to try a port-a-wraps but have really question if it is worth the extra cost.
I think if I built one like yours, it'd give me the chance to try one out, then if it was that handy, might buy a certified one.
We do mostly take downs but always seem to be working tight areas.

Have been doing about the same rigging using the large handle bars on the back of our bucket truck. I can see this being lot handier.

 

[John Paul Sanborn]

I've often wanted to try a port-a-wraps but have really question if it is worth the extra cost

Cheaper then taking a wrap on the tree? Yoobetcha!

The two biggest factors are the time saved and the known variable of applied friction, once you get to use it you have a very good idea as to how much it is going to slow down the load, vs shock-loading the whole tree.

A bollard, a name inherited from the Norman-French name Boulard still often found in Normandy, is a short wooden, iron or stone post used on a quayside for mooring ships. Mooring bollards are seldom exactly cylindrical, but typically have a larger diameter near the top to discourage mooring warps (docklines) from coming loose. Single bollards sometimes include a cross rod to allow the mooring to be bent into a figure eight.

The advantage the strap-on bollard gives is that it takes the slop inherent to using a sling with a port-a-wrap.

What makes the GRCS worth it's cost is that it adds the mechanical advantage of the winch to the system. I've had mine for over 10 years and it has paid for it'self many times over.

A bollard or porty are good for an occasional tree worker who does light rigging, but any serious arborist should have GRCS .