Mainline lag eyebolts

[TapTapTap]

Here's my 2 cents

There are 2 issues at play
1 eyebolt structural capacity
2 Embedment capacity in tree

On structural bolt capacity, the bolt has higher capacity with in-line loading which is straight down the axis of the bolt. While angled loading is okay with a reduction factor as it approaches 90 deg. Side loading away from the eye is discouraged.

On Embedment, pure tension is preferred. Angled loading is again acceptable with reductions. I think the angled loading is even more problematic since if a crack formed through the tree at the bolt then the angled loading would cause more prying on the crack and perhaps with cyclical loading when the wind blows.

[Minnesota Tapper]

Been putting up mainline wire with the j hooks. They hold very well! However I had one pull out. My fault, I had anchored it into a basswood. And I had way to much pulling on that one j hook. I'll be using only hardwood trees to anchor too from now on.
2 questions I have.

1. When I install my 1" mainline tubing can I put the finger trap tensioners on the same j hook as the wire or will that be too much pull for one hook?

2. I have a 200 foot long stretch of wire and 3/4" mainline left to put up. The only anchor tree on the top end of this line is a massive silver maple. Will the silver hold the j hook or pull out like the basswood did? Im not sure where silvers are on the range of wood hardness.

Thanks for all the help. I'm certainly learning by trial and error!

[JoeJ]

1. I put both the mainline wire and the mainline "Chinese finger" on the same J hook. I have not had any ever pull out. At this time of year,I would caution you to be careful on how tight you pull the mainline through
the tension grip. When you install the mainline, if the temperature is below 30*, be careful with how tight the line is. I replaced an old 500' 3/4" line with 1" in November a few years ago and put way too much
tension on the line and when the weather down to 0*, the line pulled apart 4" at a 1" SS Y that had double hose clamps on the Y .

2. I would anchor into the silver maple with no worry at all.

Joe

[ennismaple]

In a telephone pole they're designed to be perpendicular to the running strand or wire for strength purposes. It may be less of an issue with maple lines because the tree will grow around it.

For the start and end trees we drive the J-hooks into the the tree in line with the mainline. We crank the steel pretty tight so if it was on the side it would bend the J-hook right over. We pre-drill a 1/4" hole to get the J-hook started and then twist in until it's at the end of the threads. When we use hydro poles to get over roads we'll use a D-loop bolted through the pole.

[Kh7722]

Can i ask why use any hardware into the tree? Seems like another point of failure as well as the Mechancical ratchet tensioners. Seems like everyone i have spoken with its 50/50 on bolts and ratchets vs splice and side ties. Any discussion? Or is it a ford/chevy thing

[JoeJ]

I made the decision two years ago to use J hooks at anchor points after using end of the line wire wraps with 1/2" or 3/4" plastic tubing for 16 years. Over the years, I loosened ratchets at the end points and moved the plastic wrapped wire up or down as needed to get the end line wire out of the growing groove that the wire was in. Even though I was trying to be diligent about moving the wires every couple years, some got away from me and a few almost wrapped new wood growth completely around the plastic pipe. I then decided that using the J hooks might be better for my anchor trees than having the growth grooves. After all, I have seen spouts left in the tree overgrown with new wood, turnbuckles and cable in trees to hold large branches together covered up, and pictures of sap buckets half overgrown with wood. In all these instance, the trees were still alive.

I am pleased with the results of using the J hooks (about 40 of them) after 2 seasons. I like to run my main line straight using mostly posts and use very few tree tie backs. I use 18 gauge SS lashing wire to hang the mainline wire on the post and the same wire for tree tiebacks. If a big enough tree branch or tree comes down on the mainline, it just snaps the SS wire without damaging the pipe. I would rather have to put back up new lashing wire on four posts rather than fixing kinks or flattened mainline. At some 45* corners, I do double the lashing wire to hold the directional change tension.

Joe

[ennismaple]

Can i ask why use any hardware into the tree? Seems like another point of failure as well as the Mechancical ratchet tensioners. Seems like everyone i have spoken with its 50/50 on bolts and ratchets vs splice and side ties. Any discussion? Or is it a ford/chevy thing

My father was an electrical contractor and built power lines so we always had lots of used pole-top hardware kicking around to use in the sugar bush. We also over-built everything and used 1/4" or larger guy steel (the multi-strand stuff) and not the single strand high tensile wire. We are still using some of the same attachment points today that he put into trees 35 years ago.

If you install the hardware when the tree is not frozen you don't run the risk of splitting the tree - the damage is not much different than a taphole if you pre-drill a pilot hole. We've wrapped the mainline around the end tree and used 2x4 blocking to keep the wire out of the sapwood but over time the wood disintegrates and the tree grows so you need to re-shim the wire. Over the last 5 years we've installed some single strand #9 wire and it tends to break when a limb falls on it. We have never once had the 1/4" guy steel break.

I should also say that a lot of our mainlines are very flat - most are under 1% slope. This means we need to get them singing tight to avoid dips in the mainline. #9 high tensile wire simply can't stay tight enough over time. We also have a LOT of mainline out in the woods - somewhere above 20,000 feet - so we don't have time to mess around re-tensioning ratchets and adjusting side ties. I want to put it up once, get it straight and downhill and be done with it.

[DrTimPerkins]

Wanted to return to this recent post. We have had several different companies install tubing systems in our woods over the past 15 yrs. Several of them used anchor bolts (typically in non-crop trees), some did not. For those that did, the bolts were always installed straight in from the wire, not at a 90 deg angle. Lag bolts are designed to hold in tension (straight out), not against shear stress (from the side). Holes were predrilled, the bolt tapped in and then turned in. Occasionally we've had to back a few off a little to accommodate tree growth. We have had at least one pull out (tree rotted -- beech), with quite a bit of snap-back of the tubing system...was difficult to retension properly and get it all in the same geometry (saddles on top and in the right positions).

We just had in the past few weeks a custom 1,000+ tap installation (mainline only) commercially installed by Green Mountain Mainlines. Excellent install. Not an anchor bolt anywhere. All attachments of wire were tiebacks or supported on cedar posts and it is TIGHT.

The install itself was a bit unusual it in that it was a dual mainline system throughout, but these are not wet/dry lines. One of the lines will be used to tap ONLY red maples (~500 taps) and the other will collect sap from ONLY sugar maples (~ 500 taps). All the sap for each species will run through separate tubing, separate releasers, and separate tanks, but the vacuum pump will be the same and the trees are spread out through the entire area. This way we can quantify the sap yield, sap sugar content, sap chemistry, and timing of sap flow from the two species (including when the trees bud and the sap turns buddy). The sap will remain separate when run through an RO and then boiled in separate side-by-side evaporators before blind taste testing trials. Sap collection won't start until the 2022 season. The Principal Investigator of this work is Dr. Abby van den Berg. The work is funded by a USDA grant.

In addition, a third line was run from the shed to the sugarhouse to serve as a future pump line for that area and an adjacent area. No more trucking after that.

[sapman]

Wanted to return to this recent post. We have had several different companies install tubing systems in our woods over the past 15 yrs. Several of them used anchor bolts (typically in non-crop trees), some did not. For those that did, the bolts were always installed straight in from the wire, not at a 90 deg angle. Lag bolts are designed to hold in tension (straight out), not against shear stress (from the side). Holes were predrilled, the bolt tapped in and then turned in. Occasionally we've had to back a few off a

We just had in the past few weeks a custom 1,000+ tap installation (mainline only) commercially installed by Green Mountain Mainlines. Excellent install. Not an anchor bolt anywhere. All attachments of wire were tiebacks or supported on cedar posts and it is TIGHT.

The install itself was a bit unusual it in that it was a dual mainline system throughout, but these are not wet/dry lines. One of the lines will be used to tap ONLY red maples (~500 taps) and the other will collect sap from ONLY sugar maples (~ 500 taps). All the sap for each species will run through separate tubing, separate releasers, and separate tanks, but the vacuum pump will be the same and the trees are spread out through the entire area. This way we can quantify the sap yield, sap sugar content, sap chemistry, and timing of sap flow from the two species (including when the trees bud and the sap turns buddy). The sap will remain separate when run through an RO and then boiled in separate side-by-side evaporators before blind taste testing trials. Sap collection won't start until the 2022 season. The Principal Investigator of this work is Dr. Abby van den Berg. The work is funded by a USDA grant.

In addition, a third line was run from the shed to the sugarhouse to serve as a future pump line for that area and an adjacent area. No more trucking after that.

Dr Tim, so were the mainline ends wrapped around trees by Green Mountain?

Glad to hear about the upcoming red maple study. Too bad not starting for another year. Wish there could be a study on silvers, but I'm sure there aren't enough in your area.

[DrTimPerkins]

Dr Tim, so were the mainline ends wrapped around trees by Green Mountain?

Glad to hear about the upcoming red maple study. Too bad not starting for another year. Wish there could be a study on silvers, but I'm sure there aren't enough in your area.

I’ll get some photos to post next time I’m there (still working remotely most days).

Yes, we had originally planned to start the study in spring 2021, but circumstances slowed things down a good bit.

No silvers at UVM Proctor Maple Res Ctr other than a few hundred seedlings we’ve planted within the past 5 yrs.