Sap ladder question

[boondocker]

What is the recommended inches of vacuum for a sap ladder? Looking at lifting about 6 to 8 feet. Thanks in advance.

[maple flats]

15" will work, 25 works better. Last year I started adding a little micro leak about 30' ahead of each sap ladder. To do it, I just add a saddle (the DSD ones) a length of lateral tubing and a tiny needle valve. Then I adjust it to barely let a little air in. That works extremely well. If you don't keep a good tight system the needle valve is not needed. In my sugarhouse woods I have 5 such micro leaks and according to my vacuum gauges I lose less than 1/2" of vacuum, maybe only 1/4" but the gauges are not calibrated that small. I run about 24.5" vacuum. Before adding the micro leaks I had 25" at the releaser but the sap ladders worked so poorly that the vacuum dropped to under 20" at the end of the mains. I have 3 sap ladders on one main and 2 on another.

[pls009]

Is it best to put the needle valve on the vacuum pump side of the ladder or just past the ladder? I thought past the ladder would be best so that the leak would give the ladder some air but maybe I'm wrong - thanks

[OGDENS SUGAR BUSH]

Is it best to put the needle valve on the vacuum pump side of the ladder or just past the ladder? I thought past the ladder would be best so that the leak would give the ladder some air but maybe I'm wrong - thanks

thats where it belongs, so it helps lift the sap

[maple flats]

Yes, the slight amount of air gives the sap a lift. Just be sure you can adjust it to a tiny leak.

[BreezyHill]

1/8" Needle valves work best for the micro leak(injector) for me over the years. You want the injector to be where you can see the ladder's increase in flow rate from the injector. I like 50' incase there is a plug on the ladder and then the bubbles will slide the sap to the ladder.

Your pump is pulling all the air from the system that it can; so when you inject a bubble of air it rushes toward the pump. When it hits the ladder it speeds up the riser(s) forcing the sap up the riser.

If your system has enough gases and micro leaks already you may not need to inject anything.

to go up 6-8' you can do that with only 12" of vac very well. But as Flats stated the more vac you have the better and fast you will get the sap and the ladder to flow.

Adjust the injector during peak flow and let her be the rest of the season unless you have an issue like pooling at the base of the ladder...increase the injector, bubbles flowing up the injector and very little sap...decrease the injector.

My tallest ladder is 18' on 28+ of vac. She will run well on just 24" but at 28" she screams.

Good Luck!

[maple flats]

My tallest ladder is 13-14' and it does very well on 24-25". The needle idea I got from BreezyHill. It helped greatly and I now get just 2-3" vacuum loss between the pump and the end of the mains and each has 2 or 3 ladders and some needed a needle valve for each ladder, one works fine with just a needle valve out past the farthest ladder.

[BreezyHill]

Dave, can you tell me the slope to your ladders?

I run mine at 2%. This seems to get the sap and the air to the next ladder fairly evenly spread out. I do have to use an additional injector to compensate for additional taps added to the mains.

What size risers are you using? I am hoping to be able to change all the ladders but a few that are only upto 50 taps over to 1/2" risers this summer. Bones healed well it is the connective tissue and the head that is keeping me out of the game for this season. But you info will help me to keep the ladder program moving forward.

I have a line that is at 1" slope and I am contemplating adding two ladders so I can get to 2% slope and jump the trails they block in the bush during sap season.

We are planning to be giving sleigh rides with a team in a couple of years

Thanks
Ben

[Ontario Ian]

Glad to hear your on the mend breezy. I'd love to get down to your place and see how you do that big lift one of these days

[VT_K9]

I put my second true ladder in this year...it's only 2 feet tall, but it was needed when I made an adjustment to the mainline to improve slope for the rest of the sugarbush. The first ladder we put in last year was about 8 feet tall. It uses one set (2) six star adapters. It has about 25 taps on it. It seems to work well. The 2' ladder also has one set (2) of six star adapters. This one has about 40 taps on it and works well. I don't have an injector on either one, maybe that can improve flow. I'll have to look into this to see if it will help. Both ladders show sap movement as low at 12" of vacuum.

The other 3 "ladders" are sap tubing which wraps around a tree (to keep the systems tight) and rises about 12'. These "ladders" are on a different run to the releaser and don't show good flow until about 22" of vacuum.

Mike

[Urban Sugarmaker]

I just installed a 40" sap ladder with 6-way stars. I'm using a Shurflo 4048 and there's about 40 taps on 3/4" main going to the ladder. It's working but sap pools and fills the main about a foot or two before the lower star. This happens because the ladder lines fill solidly and work their way to the top star. Once the pump pulls the pooled sap through, the air behind it rushes up through the ladder, the lines clear, then the cycle repeats.

So I could try the needle valve micro-leak trick, or what about adding a saddle on each main and running a length of 5/16" from the higher to the lower line? This way the pump can suck air from line to line regardless of the pooled sap near the ladder.

Which would you try first? Would an air transfer line be better with 5/16 or 3/4 main?

[maple flats]

Air is not likely to help on a Shurflo pump. Change the design so that pump can push the sap to lift it, or be satisfied the way it is working.