3/16

[Eliemma]

I was wondering if it’s ok to mix and match different brand for tubing and fittings. Also wondering if the fitting with two boards hold the tubing better then a single bard. Look to use 3/16 with the. Longest run being about 140 yards and going to end it into a collection tanks. FYI I do have good slope. Thanks

[maple flats]

As long as you have the slope, distance is no matter. I have one run that is about 1300' and about 45-50' drop in elevation, it works great. As for fittings, I have only used 2 brands so for, DSD and D&G. Both held well using either brands 3/16 tubing. I can't speak for any other brands because in the 3/16 I have no experience in any others. At this point I can say some of what I've used have 1 barb and some have 2 barbs but I don't recall which was which. Both held well in my experience. There are several other brands that may be equally good, I just don't know. In what I have I have mixed those 2 brands. At first mine were all DSD but then the local D&G dealer started carrying the 3/16 and I bought from him. On the DSD I had to order and pay shipping is my only reason for switching brands. If you ever get into a mainline set up however, I still use all DSD saddles, I have found them to be the best and I've used lots of others over the years. If your 3/16 will all run directly into a collection tank, you need no saddles.

[Rockport]

HI , was reading some and wondered if you use a mainline on 3/16. I have it both ways but am strongly thinking about on my new install of just using a manifold type setup only for my 225 or so taps. Was just wondering havent really heard of anyone just soley using a 3/16 right to the tank,,, I have found I like it because there is no doubt on what lines are running and ones that are not and also the bubbles tell a lot too../// your two cents ?

[WVKeith]

On most of my runs, I go the whole way to the tank. If you have good slope, that is the way to go.

[maple flats]

I agree, in some cases, good slope and no mechanical vacuum. I go to a mainline because I also have mechanical vacuum on my lines. Another case to use a mainline would be if the distance to the tank for a large number of 3/16 lines makes it significantly cheaper to run a main. Just remember the mainline needs slope all of the way to the tank. Also be sure to account for all costs of a mainline.
In my case the mainline and vacuum were there first so when I put in some 3/16 it made good sense and cost less to run the 3/16 into the mains.
In my case for example, the nearest 3/16 lines to the tank are about 400' away from the tank, but the far end of that hill, where the last of the group of 3/16 lines are is about 1400' from the tank. Between those 2 extremes the whole hill is all 3/16 lateral lines.

[minehart gap]

I have combined Leader, CDL and Lapierre fittings to both Leader and Lapierre tubing. Single and double barb both work well for me. I have noticed that I like some fittings better than others, an example is Lapierre Tees seem to install easier for me and (just observation) clear spiles seem to produce more sap. As far as going directly to the tank, I have one lateral that I needed as much drop as possible so I took it all the way to the tank. Others I connect to a main. I have also noticed that Leader tubing is stiffer that Lapierre and with Leader tubing, if cool when installed, it will sag when it warms up.

I did the math last year and can't quite remember but I think that I figured that you can run 3 laterals tied together for the same price as the same distance of 3/4" mainline including wire.

[Rockport]

Thanks for all the comments on the 3/16 it helps when you find out what works and what doesnt .. Now for another question, I know running 3/16 is best all in series so to speak but there is always that tree is out of place !! And i have added a parrallel just to see and it worked but I wonder how well, anybody have comments on that ?

[DrTimPerkins]

Now for another question, I know running 3/16 is best all in series so to speak but there is always that tree is out of place !! And i have added a parrallel just to see and it worked but I wonder how well, anybody have comments on that ?

You will get sap from both lines if you "Y" them in together, but not as much as you will get from having the two lines separated.

[Rockport]

Thanks Dr Tim,. some is better than none ,I guess...

[maple flats]

Is there a reason why you would not run the series lateral to include that "out of place tree" in the one line? Then you will have the best set-up. In 3/16, especially if you have good elevation drop lower in the system, every tap does not need to be at a lower elevation that the previous one. It is OK to go back up hill some to pick up another tree. You just need the total elevation drop (or in some cases even no elevation drop but on good mechanical vacuum)
My first year on 3/16 near the top of the hill I had a big limb (7-8" diameter) fall on one lateral where a valley started. The lateral reached from one side to the other with about an 8-9' sag where that limb pushed the lateral to the ground in the lowest spot. I stood and watched the sap/air/sap/air/sap march down from one side, under the limb and back up to the next tap on the other side. I think I likely watched it for 5 or more minutes.

[RileySugarbush]

A couple of observations on my 3/16 system:

I have 4 runs. Top of each run is between 40 and 60' above collection point where I have a Shurflo pump pulling about 24" hg.

On one of the runs, near the top, I have to run up and over the driveway to clear delivery trucks, so 12' or so. There is some but not a lot of additional rise on the uphill side. I still get natural vacuum there, but a little less than I would if it ran flat across the drive. The small diameter of the 3/16 allows the downstream vacuum to pull the sap up. If I was to put a vacuum gage on either side of the driveway at similar elevations I think they would read close to the same. A measure at the top would be reduced by at least the change in height, but that is recovered on the run back down.

Another run has a 100' or more of basically flat run at the bottom, that picks up a few trees. The majority of the taps are higher up. On that run, the 3/16 is a disadvantage because, being flat, it is not adding any vacuum. But it is near the bottom of the run so on a good day it has high flow from all the taps. High flow in a small line create a friction back pressure that affects all the up stream taps. This spring I will transition to 5/16 in that section.

The decreasing effectiveness of 3/16 with time is a real thing. I clean my tubing with h2o2 and rinse at the end of the season and use new spiles, and take the lines down for the season. But you can see a real difference with new tubing compared to new. Visually, the lines look perfect, but there must be a film on the inside of the lines or some sort of invisible plugging at the fittings because even the second year does not run as good as the first. I was doubtful about this and thought I could clean it good enough, but it looks like Dr. Tim is right. Dang it.

[Rockport]

I was under the impression the sap will stay in the line till the next run,not a problem if the next run is soon or temps dont go high .

[DrTimPerkins]

Thanks Dr Tim,. some is better than none ,I guess...

Yes, that is true, however you should either strive to eliminate it (if possible), or minimize it to the extent possible (basically the same thing advice as using ladders). The point of going to 3/16" is to increase sap yield, but then Y-ing lines together will reduce that yield. Seems like doing is at cross purposes to using 3/16" in the first place. I can see doing it for one tree all by itself out there, but would not consider Y-ing two lines with multiple taps on each together. If you absolutely have to, then yes...grudgingly accepted, but if there is another way...go with that.

[DrTimPerkins]

Another run has a 100' or more of basically flat run at the bottom, that picks up a few trees. The majority of the taps are higher up. On that run, the 3/16 is a disadvantage because, being flat, it is not adding any vacuum. But it is near the bottom of the run so on a good day it has high flow from all the taps. High flow in a small line create a friction back pressure that affects all the up stream taps. This spring I will transition to 5/16 in that section.

This is the correct course of action for that setting. 3/16" on flat ground creates a lot of frictional resistance, reducing vacuum (and thus yield) on trees higher up the slope.


The decreasing effectiveness of 3/16 with time is a real thing. I clean my tubing with h2o2 and rinse at the end of the season and use new spiles, and take the lines down for the season. But you can see a real difference with new tubing compared to new. Visually, the lines look perfect, but there must be a film on the inside of the lines or some sort of invisible plugging at the fittings because even the second year does not run as good as the first. I was doubtful about this and thought I could clean it good enough,...

Both PMRC and Cornell Maple will be investigating solutions to this problem in the 2019 season. Unfortunately simple spout replacement or use of CV spouts don't address this particular problem -- they weren't developed to solve the problem of plugging. As far as visual inspection...it is a very poor and inaccurate way to assess tubing cleanliness. Fresh biofilms (hydrated) just don't show up very well visually. They do when they dry out some.



...but it looks like Dr. Tim is right. Dang it.

That happens every now and then. :D

[Rockport]

Thanks, to the answers. The flat run at the end is what I have been contemplating for a while, I have about a 200 ft with a 8 ft drop and have debated on a mainline or the 3/16 with 4 runs to the tank.
Cost was a good point stated earlier but i think maybe a new mainline of 3/4 would be better.

[DrTimPerkins]

Thanks, to the answers. The flat run at the end is what I have been contemplating for a while, I have about a 200 ft with a 8 ft drop and have debated on a mainline or the 3/16 with 4 runs to the tank.
Cost was a good point stated earlier but i think maybe a new mainline of 3/4 would be better.

Think of 3/16" as a balsa car. On a nice steep track it'll do well regardless of how smooth the track is. However when it hits the bottom, if you have a rough track or wobbly wheels (lots of friction), it'll slow down fast -- that would be the case if you had 3/16" tubing on flat ground. But if you have a nice smooth surface at the bottom (5/16" tubing or a mainline), there is far less friction and it'll roll a lot further. In this example, the total distance the car can go represents your vacuum level. Having friction on the flat part of the track is BAD! The further your balsa car has to go on a flat area with high friction (3/16" tubing), the less distance it can cover (and thus the lower the vacuum level in the tubing).

[lyford]

I am making my first attempt at tubing this season and have decided to go with 3/16s hooked to a shurflo. After reading this thread I'm wondering how many seasons people get out of the 3/16 tubing before it becomes to gunked up with biofilm and needs to be replaced.

[mol1jb]

Both PMRC and Cornell Maple will be investigating solutions to this problem in the 2019 season. Unfortunately simple spout replacement or use of CV spouts don't address this particular problem -- they weren't developed to solve the problem of plugging. As far as visual inspection...it is a very poor and inaccurate way to assess tubing cleanliness. Fresh biofilms (hydrated) just don't show up very well visually.

This is interesting and I will be interested to hear the results. I wonder if the per tap recommendations per 3/16 line will be reduced in order to combat this.

[DrTimPerkins]

This is interesting and I will be interested to hear the results.

You are not alone.


I wonder if the per tap recommendations per 3/16 line will be reduced in order to combat this.

I doubt it. The problem does not seem to be related to the amount of flow through the line as much as physical blockage (flow stoppage related to plugging).

[DrTimPerkins]

I am making my first attempt at tubing this season and have decided to go with 3/16s hooked to a shurflo. After reading this thread I'm wondering how many seasons people get out of the 3/16 tubing before it becomes to gunked up with biofilm and needs to be replaced.

For sanitation purposes in 5/16" tubing, unless you're using CV spouts/adapters, then replacement of droplines every 3 yrs is recommended. Alternatively you can clean with chlorine (flushing with 5-10 min minimum contact time, followed by letting the first sap run on the ground or rinsing with water). With 3/16" lines, I would imagine the recommendation would be the same in terms of use of chlorine. Replacement methods (replacing spouts annually, use of CVs) are not adequate for 3/16" tubing to eliminate plugging. Two different problems going on in 3/16" tubing...one is sanitation-induced drop-off in yield, the other is physical plugging of lines.

[Eliemma]

I wonder if if using hydrogen peroxide instead of chlorine bleach for sanitation purposes would help with 3/16 and bio film build up I the tubing?