3/16 or 5/16 without mainline

[Nemo5]

Hello. I've been putting out 100 buckets every year for the last 7 years but this year I would like to also try some tubing. My plan is to run 500' of tubing and have a shurflo pump on the end for vaccum. I will have about 17 taps on this line. There is probably 15' of drop from first tap to last. I will not have 30' of drop after last tap. Would it be best to go with 3/16 or 5/16 or does it matter?

[psparr]

3/16. Any drop is good drop.

[billyinvt]

I was under the impression that with mechanical vacuum or "flat" terrain after last tap you're best sticking with 5/16 for the increased volume. Is it less cut and dry than I think it is?

[maplestudent]

it seems that with the slope you describe, you'll get some natural vacuum with 3/16" but not the full potential. However you mention using a shurflo, and therefore the "less than 30' of drop after last tap" becomes kind of irrelevant; you'll have mechanical vacuum so you won't need the natural vacuum. I'm not sure if anyone is using a shurflo with 3/16", but a lot of people have commented on using it with 5/16 and mainlines, or all 5/16.

I don't really have a straight answer for you, but I will share my experience. First I'll admit my setup is not the most efficient. I use all 5/16", no mainlines. This is due to mainly 3 things: I got several rolls fairly cheap, I didn't have the funds and/or time to set up mainlines, and I wasn't going to have the time to collect 90 buckets every day.

So I ran two main runs, with side runs of varying length & tap counts. I have short side runs with a single tap, I have short side runs with as many as 8 taps. I have a long side run (say 150') with 2 taps, and I have a long side run (probably 250') with about 15 taps. And everything in between. Basically I did what I needed to do to get everything on tubing. One main run is about 2000' total, 56 taps. The other is about 950' total, 34 taps. I hooked both runs up to one shurflo. I more than doubled the highest amount of sap I've ever collected.

One of the things I noticed was that on marginal days, such as days the temp was a few degrees above freezing and the sun was not strong or it was cloudy, I got a lot of sap where in the past, on buckets, only a few select trees would produce.

Bottom line is that for me, this is much more efficient. I'd agree that it most likely could be better, but for now, this works for me.

[Super Sapper]

The flat ground with 5/16 is for gravity systems, with the shurflo you should be good as long as you do not put too many on the 3/16 (Greater than 35).

[DaveB]

I have a very similar setup, although when you say 35' drop at the end, do you mean in elevation or 35' to the pump? In one of my setups, I have an almost "star" pattern with 5/16 tubing going out with some lines being about 500' long. There's a total of 6 lines, each with no more than 10-15 taps. They all connect to a star fitting which is at the end of 1/2" pipe that is 20' long. That pipe is connected to the Shurflo. One of the key suggestions that someone made with the Shurflo's was that they performed best they always had sap in the line and so I added the extra length to create that kind of queue.

I used to have a more traditional tubing setup with laterals feeding a 3/4" mainline but an opportunity came up last year when it was time to replace the older tubing and I just decided that this was a more time and cost effective way to go.

[Nemo5]

I will have no drop after my last tap. I think I'll go with the 5/16 and see what happens.

[Bucket Head]

I have no mechanical vacuum experience and I have a little natural vacuum experience. With that said, I can say that 3/16 performance suffers if the land (slope) is nearly flat where it approaches and/or reaches the collection point. I have a mix of 3/16 and 5/16 this year, even going back to 5/16 in one location because of the flat area prior to my barrel. We'll see if the new locations this year perform any better with 3/16. Unfortunately, all my tubing locations start out with great slope but they level out for quite a ways before my barrels.

The 3/16 must have significant drop past the last tap for the line to run well. Otherwise, the sap slows considerably in that flat area. Just food for thought when you are looking at your bushes and collection point choices.

Steve

[huxta]

this is my first year tapping and I went with 3/16. I have 4 runs down a slope. 3 have a 20+ ft slope after the last tap. 1 Has a 5 ft slope after the last tap with several taps under 20 ft. I see no difference in the flow rate between the different runs. (all runs have a 50 ft drop from top tap) Could I be losing some vacuum on the last few taps of the lower run? Sure, but I cannot see any noticeable difference in the flow. The steeper run is the one with 5 ft from last tap and runs sooner than 20+ ft from lower tap with a more gradual slope. All 4 runs at about 25-29 vacuum. Again, this is my first year tapping so I am by any means no expert. I have never used 5/16. Just giving info on my experience. And after re-reading your post, if you are using a shurflo, 5/16 may be better. From what I have read, 3/16 provides better "natural" vacuum. 5/16 may be better with mechanical vacuum.

[markcasper]

One thing in all of the 3/16 talk that I have not noticed is: When saddles came out, star fittings in the mainline basically were considered a NO-NO. Does this still apply? I have not seen any info on this. I am setting some up right now and at the end of the mainline I'm wondering if this would be considered ok once more?

[Cody]

One thing in all of the 3/16 talk that I have not noticed is: When saddles came out, star fittings in the mainline basically were considered a NO-NO. Does this still apply? I have not seen any info on this. I am setting some up right now and at the end of the mainline I'm wondering if this would be considered ok once more?I would think with vacuum being created in the lateral it wouldn't matter,but if it was a hybrid system it would.

[WESTVIRGINIAMAPLER]

When you say star fitting I assume you are referring to the 4 way or 6 way screw in NPT threaded fittings that screw into a Female threaded mainline connector. The only place I would cut mainlines is where only necessary to connect them together or where you are connecting 2 rolls together. I would rather put in 6 good saddles than one of those type fittings. If you are referring to the top of the mainline for 3/16, i always use the double forks. I have one place where I have 6 lines and probably over 100 taps coming into 2 of the double forks. There are much better ones out there than the old blue double forks. I've had issues with the 4 way and 6 way star connectors breaking in the past.

[KevinS]

The flat ground with 5/16 is for gravity systems, with the shurflo you should be good as long as you do not put too many on the 3/16 (Greater than 35).
I am completely new to tubing also. on the 3/16 are you using health tees to add a tap to the line?

[Nemo5]

Well my shurflo setup is working very well. I went with about 400 feet of 5/16 tubing and 26 drops. I was pulling about 17" of vaccum until I added a recirc/bypass line and then I was pulling 27". The only problem I am having is before dark I like to shut the pump off and fully open the recirc/bypass valve to have it bypass the pump. When I do this the 27" of vaccum sucks everything in the line way up into the line and the drops. The only thing I can think of to do is add a valve at the upper end beside the vaccum gauge so on my way to shut the pump off I could open the valve to release the vaccum then shut pump off and open recirc/bypass valve. I am wondering if after I have everything bypassed should I go back and close that vaccum release valve to keep the system closed or leave it open for the night?

[CampHamp]

Well my shurflo setup is working very well. I went with about 400 feet of 5/16 tubing and 26 drops. I was pulling about 17" of vaccum until I added a recirc/bypass line and then I was pulling 27". The only problem I am having is before dark I like to shut the pump off and fully open the recirc/bypass valve to have it bypass the pump. When I do this the 27" of vaccum sucks everything in the line way up into the line and the drops. The only thing I can think of to do is add a valve at the upper end beside the vaccum gauge so on my way to shut the pump off I could open the valve to release the vaccum then shut pump off and open recirc/bypass valve. I am wondering if after I have everything bypassed should I go back and close that vaccum release valve to keep the system closed or leave it open for the night?

Couple thoughts... you could leave the pump running until after the freeze (that's what I do) and the mainline maintains vacuum through to the defrost or you could release the pressure more slowly (open valve slightly for a couple minutes during re-compression) so it's not forcing sap up your mainline like a cannon and the air can travel over the sap.

[maple flats]

Use check valve taps next time. When everything is sucked back up, it is sending contaminated sap into the tap hole, that starts the tree's response to close that leak.

[Cedar Eater]

Use check valve taps next time. When everything is sucked back up, it is sending contaminated sap into the tap hole, that starts the tree's response to close that leak.

Are check valve spiles helpful on 3/16" natural vacuum lines? I've been wondering what happens when the lines start to freeze at night, especially for the lowest trees in the line.

[psparr]

Are check valve spiles helpful on 3/16" natural vacuum lines? I've been wondering what happens when the lines start to freeze at night, especially for the lowest trees in the line.

Not really. The line will always have vacuum on it until it freezes. So the sap isn't drawn back into the tree.

[Cedar Eater]

Not really. The line will always have vacuum on it until it freezes. So the sap isn't drawn back into the tree.

Thanks. I don't think they make check valve spiles with 3/16" barbs yet, so that spares me some conversion effort.

[Maple Hill]

Thanks. I don't think they make check valve spiles with 3/16" barbs yet, so that spares me some conversion effort.

CDL makes a t that you can use a 5/16 drop on.

[Cedar Eater]

CDL makes a t that you can use a 5/16 drop on.

I have those on one of my saplines, but the other two have 3/16 X 3/16 X 3/16.