3/16 tubing - we are believers

[Snowy Pass Maple]

I just went to check our new 3/16 setup today - 21 taps were overflowing my 55 gallon drum far before I would have ever expected. This is really amazing stuff and we will surely use a lot more next year.

We posted a handful of photos on our facebook page including our maxed out vacuum gauge and a few descriptions.

My next thought is that this method, combined with a battery-operated diaphragm pump is the best of both worlds for remote locations using 20-100 taps - use the battery-driven pump to get the flow started in slow periods, and then let natural vacuum keep it rolling and preserve the battery.

[huntingken111]

That is awesome thought of trying it next year. Do you have alot of slope to the 3/16 line

[Randy Brutkoski]

I know a guy near me that had 21 inches on a run last week using 3/16.

[Snowy Pass Maple]

That is awesome thought of trying it next year. Do you have alot of slope to the 3/16 line

I wouldn't say it's exceptionally steep - this is why we made sure to make the final tubing run after the last tap long enough (around 250 feet) that it could accumulate a good vertical drop over the run. I need to go up with my altimeter to get a little better measurement of the system.

One thing I'm wondering is just how long a run the 3/16" could handle. For example, we could run this a 1/4 mile and come all the way down the hill to a creek and pick up right there.

And a nice bonus with this setup is that the tubing costs a little less than 5/16" and uses less plastic - thus less waste at end of life!

[Clinkis]

So what is the advantage of 3/16 over 5/16? Better vacume? The results speak for themselves but just curoious why.

[Snowy Pass Maple]

Checked again this morning - 34 degrees, still flowing, and vac. gauge pegged at 29.9 inches of vacuum!

[Gary R]

Mine ran about 27" last year. This year I haven't kept up on leaks an I'm still at 25". The advantages are that this vacuum level is at the tap hole. Normal vacuum system has best vacuum at the pump. The disadvantages are that you need slope and a leak will really slow the flow where as a pump can overcome some of that.

[BlueberryHill]

I have 30 taps at my brothers house on 3/16. 2 lines. 1 with 12 and 1 with 18. Feeding a 55 gallon drum. I emptied his drum last night at 8:00 and he just sent me a text this morning saying that the drum is already half full. I am very impressed with this setup. I have almost 90 on buckets at my house and he gets about the same amount of sap that I do with just those 30. Man, I wish I had a hill like he does! I also wish he had more maples on his hill. I could probably get 5 more taps if we really stretched it out, but thats it.

One line had 26" of vac last night and the other one was at 8". I actually think I might just have a gauge issue on the 2nd one because I have spent a lot of time looking for leaks and have not found anything wrong. Both lines seem to be moving at the same rate where they feed the drum too. Anyway... 3/16 gravity is where it is at!!

[Ittiz]

Checked again this morning - 34 degrees, still flowing, and vac. gauge pegged at 29.9 inches of vacuum!

What pump are you using? Usually only the automotive AC draining pumps are rated for that. Also are you sure your gauge is calibrated correctly? I threw the calibration of a gauge off once when there wasn't a lot of air volume to pull and the pump tacked the gauge too quickly. I'd attach two gauges at once to cross check the value. If it is at that value be really careful it could boil the sap in the line and cause it to clog.

[Dave Lister]

That’s awesome. I’ve gotta get a vacuum gauge to see what my setup is pulling. I have 13 taps on a 1000 foot run of the 3/16 tubing with a 20 foot drop over about 75 feet at the end. It’s collecting almost as much sap as my older run with 90 taps on gravity with 5/16th to a 1 inch mainline. Definitely going to be doing a lot of work out in the woods this next season. I’m totally convinced.

[ryebrye]

I have 30 taps on 3/16. I have one line reading 28", another with 25" and another that has a leak somewhere and only gets around 18" - but I have a 30 foot drop at the end of them all. My lowest tree is on that line that has 18" at the top but it reads 22" at the tree.

I haven't overflowed a 55 gal drum yet but I may get another drum ready before it warms here based on what others are saying.

I think next year I might be able to talk to my neighbors and get a hundred or more trees - I'd run a diaphragm pump mainline with 3/16 gravity lines feeding into it if I do.

A friend has a traditional mechanical vacuum system - he's going to try setting up some 3/16 this year on it and see what levels he gets at the tap with 3/16 and a mechanical vacuum combined.

[NE PA Maple]

9307

Photo of the vac on my 3/16 line that was running yesterday. Only one of my two lines was running. The second hadn't warmed enough yet.

This line has 14 taps on it and I figure the max drop to be roughly 30 - 35 feet. (I haven't verified this yet).

Being my second year, this is the first time we have run tubing. The wife and I are amazed by how well this works. My father in-law actually stopped by just to see the sap flow one afternoon, his buckets weren't even running at the time.

It is really impressive to go to a tap on these lines and watch the difference in how it lets the sap push out of the tree vs a bucket tap.

For anyone with some elevation change and a good collection point, I would highly recommend this set-up.

[Snowy Pass Maple]

I also wish he had more maples on his hill. I could probably get 5 more taps if we really stretched it out, but that's it.


Funny you say this - I was also second-guessing this trial after realizing how much tubing I was using per tap - I think I ended up close to $5/tap since the trees are not nearly as dense as other areas we setup tubing. But those concerns were quickly put to bed when I saw that barrel filled up - I figure the return on investment is a no-brainer :-)

[Snowy Pass Maple]

What pump are you using? Usually only the automotive AC draining pumps are rated for that. Also are you sure your gauge is calibrated correctly? I threw the calibration of a gauge off once when there wasn't a lot of air volume to pull and the pump tacked the gauge too quickly. I'd attach two gauges at once to cross check the value. If it is at that value be really careful it could boil the sap in the line and cause it to clog.

What?!? You don't believe my $6 e-bay gauge? I was ready to propose maple taps to take over the turbomolecular vacuum pump market! :lol:

Seriously, yea, I'm sure there is some uncertainty with the gauge as the lines are not boiling yet... it's brand new and hasn't ever been exposed to a pump to damage it - but it's also not seen a serious calibration either. Just thought it was a great photo!

[Ittiz]

What?!? You don't believe my $6 e-bay gauge? I was ready to propose maple taps to take over the turbomolecular vacuum pump market! :lol:

Seriously, yea, I'm sure there is some uncertainty with the gauge as the lines are not boiling yet... it's brand new and hasn't ever been exposed to a pump to damage it - but it's also not seen a serious calibration either. Just thought it was a great photo!

If you bought it on ebay then you probably bought it from the same people I bought mine from. It's really easy to throw the calibration off of those gauges. The first one I bought read 5 inches when I took it out of the box and they had to send me a new one. The second one I threw the calibration way off when I tested it because I connected it pretty much directly to the pump and it just blew way past 30". I just finished re-calibrating it the other day. Which isn't easy since they aren't made to be re-calibrated.

[NE PA Maple]

93279328

Just got back in from checking my lines. Both are running today. 6 taps on one line, 14 taps on the other line. Both pulling good vac.

Still doesn't cease to amaze me. Guess I'm pretty easy to amaze LOL.

[psparr]

I bought an old automotive vac guage off ebay. New in box. Not sure how accurate it is but it holds 22" when shes running, and my barrels tell the same story.

[PACMAN]

Do they make a saddle for 1 inch mainline for 3/16 line?

[ryebrye]

Today the sun was out and I got 29.5" on one of my lines. Since the barometric pressure was 29.9" today, I was pretty pleased.

My other lines were at 28" and 25".

9337

[PACMAN]

Let me ask something? Do you think it is posable to use the reducers from 5/16 to 3/16 to hook into a sadle on a 1 inch mainline? I have 500 on line now with 5/16,but I am thinking on maybe puting on another 200 or so for next year.I will have to run another section of 1 inch main line.The slope is steap and the laterals would be 250 ft or so,with 15 to 20 taps per 3/16 line.

[WESTVIRGINIAMAPLER]

With pulling that much vac, is the sugar content lower than normal gravity?

[Snowy Pass Maple]

To answer a couple questions -

Regarding sugar content, I haven't tapped these trees before to have a reference but it was my understanding that sugar isn't affected by vacuum.

Regarding connecting these to saddle fittings - you could just use another transition fitting when you go back into the mainline with a short piece of 5/16" tube between the saddle and transition fitting. But to get the benefit of the 3/16" tubing, you'd then need many feet of rise (ideally at least 30) from the mainline connection up to your first tap. In this kind of setup, the drop of your mainline wouldn't really count towards getting vacuum.

On the ebay gauges - the one I bought read correctly out of the box, and I have not shocked it with anything, so I can't complain... Someone else suggested the auto gauges - those are probably much tougher. I think I have an old Craftsman gauge that is probably much better quality in my garage - I might try that out as well.

[ryebrye]

I don't think so, but you could use a reducer and a small section of 5/16 tubing to connect to an existing 5/16 saddle. It'd increase your cost slightly (the adapters are around $0.40) - you have to use the same 5/16 -> 3/16 adapters at the dropline anyway so if you do 3/16 you'll have plenty of the 5/16 -> 3/16 couplings (although I think it's actually technically the McMaster Carr 1/4" -> 3/16" that most people are using at the moment - though some are using the ones that D&G is reselling, not sure if they are true 5/16" -> 3/16" or not)

I bet in the next couple of years manufacturers will start to make a lot more 3/16 stuff as it catches on and gains wider use.

[sapdog]

More personal experience supporting 3/16" lines. Thanks for sharing.
my woods are on a very steep hill, and I've been slightly overloading my 5/16" lines (20-25 taps per run) to some vaccuum success (haven't measured, but it's apparent). I can't wait to try 3/16" in years to come - really seems like a natural decision for a lot of sugarmakers.
keep it flowin!

[PACMAN]

If 3/16 does create the same vacume as a pump, why wouldnt the large producers use it and not buy releasers and pumps?There must be some reason why they are not. I know I am going to try it next year on 200 taps next to my taps I already have.

[TheMapleMoose]

I brushed off the notion of 3/16 tubing at first but it is very intriguing. Are the signs for pinpointing leaks the same as we use for vacuum with a pump?

[psparr]

I brushed off the notion of 3/16 tubing at first but it is very intriguing. Are the signs for pinpointing leaks the same as we use for vacuum with a pump?

The sap will speed up, and youll notice more bubbles in the line.

[GeneralStark]

If 3/16 does create the same vacume as a pump, why wouldnt the large producers use it and not buy releasers and pumps?There must be some reason why they are not. I know I am going to try it next year on 200 taps next to my taps I already have.

There are a couple larger producers that are starting to use 3/16, and I'm sure more will. But, with 3/16, leak management is key whereas a pumped system can overcome leaks. Also, retrofitting an established system with 3/16 would be quite expensive so if you have a pumped system setup that is designed for high vac., it is not worth tearing it out and starting over with an experimental system. When you income depends on making syrup, you are not going to experiment.

The larger producers I know of that are doing this are trying it on woods that are remote and difficult to set up pumped systems. That will likely be where this will take off. I am looking at a couple leases in my area that are on good sloped land and am leaning toward trying 3/16. These would likely be in the 300-500 tap range.

[Machinist67]

140 taps March 2 on 3/16 line, 1900 gal so far, sap started 2.4 now 1.8. I am a believer! The only change next year will be to remove lateral lines. Some trees are still not giving up sap

[PACMAN]

Well,its to late this year to try.I will try some next year.If this works,I have 8000 taps in my bush and I dont have power and its to remote to get power for anything electric so I depend on gas motors.If it works as good as everyone is saying,that would save me from buying a pump and releaser.

[WESTVIRGINIAMAPLER]

Who is selling the 3/16 line and fittings for it?

[DrTimPerkins]

If 3/16 does create the same vacume as a pump, why wouldnt the large producers use it and not buy releasers and pumps?

3/16" tubing can work quite well, but like everything else, it works well in the proper application, and doesn't work so well if the proper conditions are not met. In the case of 3/16" tubing, the conditions necessary for good results are that you MUST have good slope, and you MUST maintain your system vacuum tight.

[ryebrye]

Who is selling the 3/16 line and fittings for it?

D&G have 500 ft rolls of tubing and they also sell fittings. There are also fittings available at McMaster Carr - part numbers for McMaster Carr are included in the paper by Tim Wilmott

[ryebrye]

3/16" tubing can work quite well, but like everything else, it works well in the proper application, and doesn't work so well if the proper conditions are not met. In the case of 3/16" tubing, the conditions necessary for good results are that you MUST have good slope, and you MUST maintain your system vacuum tight.

Would 3/16 tubing with a shallow drop going into a mainline under vacuum potentially yield a higher vacuum than 5/16 going into the same mainline?

[CampHamp]

Would 3/16 tubing with a shallow drop going into a mainline under vacuum potentially yield a higher vacuum than 5/16 going into the same mainline?
I think that your vacuum levels would get higher through the mainline faster because there would be less air to evacuate. However, for the vacuum effect to get up to the taps, you'd need to pull the sap column which would be more friction (and may take longer) than sending vacuum pressure over-top the liquid and by "pulling bubbles forwards". So, no I have no idea! Tim Wilmot probably knows this answer. He was working on it, I believe.

[DrTimPerkins]

Would 3/16 tubing with a shallow drop going into a mainline under vacuum potentially yield a higher vacuum than 5/16 going into the same mainline?

Possibly. That is the subject of some research this spring (assuming the sap eventually runs some). The conditions needed for an additive effect are being investigated.

[windyacres]

700 on 3/16. No sap yet in Muskoka till probably Friday. Last nite was - 14 farenheit. The cold is starting to loosen spiles, this is not good for 3/16 as it makes for leaks. this means checking 700 taps before main seAson. a lot of last years lines are under snow. I find the small lines more prone to sagging with snow ice as the are not as strong. solution - put them as high AS POSSIBLE,EVEN SHOVE THEM UP IN FALL- SAVE A PILE OF WRK COME SPRING. Still 30-34 inches snow in bush.

[ryebrye]

9498

I got just a hair under 30" this morning... And it's still holding steady.

There still isn't much of a flow - my 30 taps are doing about 1 gallon of sap per hour - but hopefully things will pick up this week.

[steve J]

I yet to get my vac gauge to read on any line but I can say its flowing fairly well on one line and moving slowly on the other while my 5/16 is doing nothing and buckets are mostly dry. Temps at night have not gone below freezing last two nights.

[Cabin]

Ok Where does this 3/16 tubing come from(leader does not seem to list it) and is the tap hole 3/16 as well??? are the 'mains' 3/16 as well?

[Maplewalnut]

9498

I got just a hair under 30" this morning... And it's still holding steady.

There still isn't much of a flow - my 30 taps are doing about 1 gallon of sap per hour - but hopefully things will pick up this week.

Are you saying you are getting 30 inches of vacuum on a 3/16 gravity line?

[ryebrye]

Are you saying you are getting 30 inches of vacuum on a 3/16 gravity line?

Well... I wouldn't say a full 30 - the gauge is just BARELY under the 30. It's probably 29.9" or so.

[ryebrye]

Ok Where does this 3/16 tubing come from(leader does not seem to list it) and is the tap hole 3/16 as well??? are the 'mains' 3/16 as well?

Dominion and Grimm. The best info on it is in Tim Wilmot paper on the pmrc website

[NE PA Maple]

I had 26 1/2" on one line and 27" on the other today. Running beautifully today:)

[Cabin]

Dominion and Grimm. The best info on it is in Tim Wilmot paper on the pmrc website

Well I guess I will have to wait for them to update their web site. Got some 3/16 clear tubing from home depot yesterday to play with tomorow. Now to figure out how to attach it to the spiles.

[steve J]

I am not sure what is going on with my gauges and I did not get to check them until 7 last night as I was boiling all afternoon. I have yet to register anything on my gauges but I can tell you that my 3/16 was running two hours before anything else and it produced about 3 times more sap per tap than gravity 5/16 or buckets. Today will be the first great day as yesterday I had strong wind most of the day

[Machinist67]

Well I guess I will have to wait for them to update their web site. Got some 3/16 clear tubing from home depot yesterday to play with tomorow. Now to figure out how to attach it to the spiles.

G&D has the tubing on their website page 37 left column look for the blue circle (NEW). http://www.dominiongrimm.ca/templates/dominiongrimm/html/catalogue/usa_en/ You will need 3/16 T and a 3/16X5/16 connectors. Then take 5/16 tubing to your spouts.

[Cabin]

G&D has the tubing on their website page 37 left column look for the blue circle (NEW). http://www.dominiongrimm.ca/templates/dominiongrimm/html/catalogue/usa_en/ You will need 3/16 T and a 3/16X5/16 connectors. Then take 5/16 tubing to your spouts.

Thank you I will keep that in mind for next year.

[Forrest hunters]

Will this system still work with minimal slope? I may be able to get 5-10 feet of vertical. I am not as much woried about max vacuum but ease of getting sap. Right now I walk all over and this would centralize a pick up point. Will it hurt flow over bags by such minimal slope? May even have to run some lower trees on a seperate line near drum just to colect easier. What about running 50-100 feet of tub around a tree near barrel just to get more volume in the line and possible create more vacuum?

[Dave Lister]

While I haven’t tried setting up the 3/16th tubing on a shallow slope like what you are describing (I will be doing it this next year on a small run though), I imagine even with a 5-10 foot drop, you will still produce some vacuum which is much better than using bags and having no vacuum. Even if the vacuum level is at a minimum, I would suggest using tubing to collect as much sap in one location, if anything just to save time spent walking through the woods on snow shoes lugging sap around.

[Goggleeye]

I too have minimal slope and was wondering how this would work. Those of you have been running 3/16, what is your syrup per tap looking like? I run all 5/16 tubing on minimal slope (10-30 taps on 5-20 feet total slope, and the past two years I have produced 1.44 qts and 1.7 qts per tap, with probably over 100 of my 460 taps come from sub 10" trees and many from the 7-8" range. Aren't those pretty good ratios? Do you think 3/16 would put me over 2 qts/tap, weather cooperating? Not that I have the evap capacity to handle more sap!

[StayinLowTech]

I put vacuum gauges on two runs of similar slope, one run of 5/16 and one of 3/16. Yesterday (not a heavy run) the 5/16 line was 3" and the 3/16 was 8" of vac. On a steep slope I often get around 25 to 26.5" vac.

[Forrest hunters]

So this could work with minimal slope and possibly out produce bags. I would just love the simplicity over lugging with the same as i get now.

[DrTimPerkins]

Will this system still work with minimal slope?

Unfortunately not with 'minimal' slope. Without decent slope, the small line results in the development of back-pressure and you'll get less sap than you would with a bag or bucket. Regular 5/16" tubing will probably do better as long as there is a minimal amount of slope. Slope is required with 3/16" tubing, although there is some ongoing research looking at having modest vacuum and various slopes in 3/16" tubing to generate high vacuum.

[BAP]

Dr Tim, has any research been done on 5/16" tubing and the natural vacuum effect like the 3/16"? I was wondering if putting more taps on a 5/16" line would get the same effect as the 3/16 with less taps. Back 30 plus years ago, we used to run lines with anywhere from 30-100+ taps, like a lot of people at that time did, and got a lot of sap of places with steep grades. I wonder if we were getting this natural vacuum effect.

[DrTimPerkins]

Dr Tim, has any research been done on 5/16" tubing and the natural vacuum effect like the 3/16"?

Yes, but a long time ago. As you recall, it takes a good number of taps to fill a 5/16" line, which is why the recommendations for tapping on sloped land with 5/16" is very different between gravity and vacuum lines (gravity lines you want many taps, vacuum lines you want far fewer taps). The 3/16" line will develop a natural vacuum with less taps.

[Forrest hunters]

DrTim,
Can you define minimal slope or what you believe to be the minimum to run this set up. I could probably get 15' from first tap to top of drum I would want to empty into. With that being said what kind of slope do I need for the trees to get there. Maybe put 10-20 taps per line. I could have runs of a couple hundred feet each.

[DrTimPerkins]

Can you define minimal slope or what you believe to be the minimum to run this set up. I could probably get 15' from first tap to top of drum I would want to empty into.

Each ft of head is a little less than 1" Hg. However keep in mind that sap in a line also contains bubbles, which do not contribute to the head. Also, this applies only to the change in elevation from the outlet (the top of the storage drum) to the tree. So if the tap in your last tree is 15' higher than your drum, you might get about 10-12" Hg, but if your last tree is only 1 ft, you'll get almost nothing there. The problem on minimal slope is that (theoretically at least) the capillarity and friction of the tubing starts to play a bigger role in the overall sum of the equation, so if you don't have enough sap weight to push the liquid out of the tubing, it will just add to the friction, and create a back-pressure which can impede sap flow. You definitely don't want to use 3/16" on flat land.

As I've said before, Tim Wilmot (UVM Maple Extension) is the expert on this and has done all of the research, so best to direct these types of questions to him. There is still more to learn.

[Jeff E]

It was mentioned that the number of taps on a line plays a big role, and is different with 5/16 and 3/16.

So for an example, does anyone now the best number of taps for a 5/16 line with 30 ft of head, and also for 3/16 line with 30' ft of head?
And is the best practice to run these directly to a tank, or could you have similar success running to a mainline?

[ryebrye]

It was mentioned that the number of taps on a line plays a big role, and is different with 5/16 and 3/16.

So for an example, does anyone now the best number of taps for a 5/16 line with 30 ft of head, and also for 3/16 line with 30' ft of head?
And is the best practice to run these directly to a tank, or could you have similar success running to a mainline?

The number of taps to get a high vacuum in 5/16 was studied, but in the study they found that 10 was not enough.

For 3/16 - as few as 4 could be enough.



For high vacuum, the minimum number of taps to place on a 3/16" line approximately 150' long is 4 or perhaps even less; the minimum number of taps on a similar 5/16" line is as yet undetermined, but is greater than 10. This assumes a good vertical drop below most of the trees.


(see http://www.uvm.edu/~pmrc/highvacuum.pdf for more details)

[pls009]

Has anyone discovered that they have ran too may taps into one run? I have great slope and am trying to get a feel for how many taps that I can put into one run. Thanks for your insight!

[Snowy Pass Maple]

Just another update on this thread - we have not had a single leak with the D&G tubing and fittings through the whole season on our small test area - anytime it flows, I see 29.9 on the gauge.

Total of 21 taps with about 500 feet of tubing on two main branches that we merged and then ran 250 feet after the merge to help ensure good vacuum to the bottom taps. We consistently saw 3x the production of 5/16 gravity taps when running, and saw many 1-2 gal/tap runs on the 3/16 taps when we only had a dribble on the 5/16.

I was a little worried with the single barb, but it worked great. We also installed them without a tubing tool - just used a hot thermos to dip the end. The D&G tubing was very pliable and easily slid on 100% and held tight. We made the transition to Leader's 5/16 max flow flex and used Leader's clear check valve taps. Overall, it was an absolute pleasure to work with as compared to the 200-some taps we put in with 30P.

We have also been a little less paranoid about maintaining perfect slope simply because the sap fills and moves so quickly - so we have not stretched it quite as hard as 30P. And given that it's a bit softer, not sure we would want to.

If we expand again next year, it will all be on 3/16" on an area with at least 100 foot drop potential.

My D&G Wish List for 2014:

1. 3/16 tubing in grey - this would be very helpful recognizing that these 3/16 applications may be particularly popular with small producers who often have to work in areas where aesthetics can make or break getting permission to setup the tubing. We have gotten many compliments on how well the Leader 30P grey blends in compared to some tubing sites that look like a trash dump in the woods.

2. 3/16 clear taps - it has to be coming... will greatly reduce cost and time!

[steve J]

I never did get any readings from vacuum gauges and I suspect I did not set them up right. What I did was use the leader end tree fitting and ran my 5/16ths around the tree with a gauges connected to it on 5/16ths as well as one tap. I did not hook on the 3/16ths until I had gone thru the fitting upon wrapping the tree. How did everyone else make this connection?

[StayinLowTech]

Not sure how you would determine that there are too many on one run, but Dr. Tim Wilmot said that he has tried up to 33 without the line being overloaded.

[bowhunter]

Colin, What kind of fittings did you use to go from the 3/16 to the 5/16 if any? I don't have more than 10-12 feet of drop to work with, but I'm still temped to try it. Did you guys try it on less than 30 feet of slope anywhere? Thanks.

[Machinist67]

try this pt# 1040-2
http://www.valueplastics.com/search/search.aspx

[ryebrye]

I've had really good results as well. My taps have been flowing without any freeze for four or five days at close to a gallon per tap per day. I'm getting roughly five times more sap on my 3/16 tubing as I am on a single tree i have on a bucket.

My gauges are almost always pegged. After a freeze/thaw the spouts will sometimes loosen ever-so-slightly and I'll be down to 29.0 - walking the line and slightly tapping all the taps to reseat them will bring me back up to 29.9

I've heard that both d&g and CDL might make 3/16 spouts (well 5/16 holes into 3/16 tubing obviously)

CDL will also make 3/16 tubing. I hope they make gray.

[steve J]

I did a small run of 3/16th that had just four trees and I am guessing my drop was between 15 and 18ft. It did not run as fast as my other lines which all had at lease 30ft but I still thought it wwas faster than 5/16ths.

[steve J]

I am going to add more 3/16 taps next year. I have the potential to extend one of my lines with about 12 taps on it to about 25 taps. Right now this line starts at the top of the steep at the edge of a shelf on the hillside. This shelf is about 75 ft wide with 5 trees on it than there is another steep rise with 8 to 9 trees and the highest tree would be in excess of 30ft above the shelf, once the sap traveled across the shelf it plunges around 50 down the next steep to the main line. The question is rather that shelf will be to big an obstacle for it to work well? any thoughts?

[ryebrye]

I am going to add more 3/16 taps next year. I have the potential to extend one of my lines with about 12 taps on it to about 25 taps. Right now this line starts at the top of the steep at the edge of a shelf on the hillside. This shelf is about 75 ft wide with 5 trees on it than there is another steep rise with 8 to 9 trees and the highest tree would be in excess of 30ft above the shelf, once the sap traveled across the shelf it plunges around 50 down the next steep to the main line. The question is rather that shelf will be to big an obstacle for it to work well? any thoughts?

If you are talking about just going down the shelf, I don't think this will be a problem. I have something similar in my setup with all of my trees on a sloped area that ends with a 30 foot drop-off. The tubing can span 75 or 100 feet without any problems - you'll want to find a way to keep it tight.

If you avoid leaks, you will get really good vacuums at the taphole with those kinds of drops.

[Snowy Pass Maple]

Colin, What kind of fittings did you use to go from the 3/16 to the 5/16 if any? I don't have more than 10-12 feet of drop to work with, but I'm still temped to try it. Did you guys try it on less than 30 feet of slope anywhere? Thanks.

We used the fittings from D&G - they are just straight transitions with single barbs on each end and a central ring/stop for the tubing between the sections. They were $0.30; tees were $0.50. Since the transition is 2x the cost of the tap, this is why getting 3/16 taps will make this approach a lot cheaper! That being said, I wouldn't try to cheap out on a fitting elsewhere unless I knew it was the exact same source - these went on easily and held really well and as so many of these threads have shown, the results have been quite variable as people figure out which parts work. I was just a really happy customer with what they supplied.

We didn't try this anywhere with lower slope - but I will certainly give it a shot next year if we setup anything with at least 10 feet drop after last tap.

I think the ultimate combo would be to combine one of these diaphragm pump setups with 3/16" tubing and enough control logic that could use the pump to get the flow started and then switch itself out of the way once the sap is running and vacuum is achieved - which would also greatly extend the operating or battery life in a remote application.

My understanding is that the only real shortcoming with 3/16" vs. traditional vacuum is that you don't get vacuum until the sap starts filling the line under gravity flow. The 3/16 would also have an advantage of a lot less volume to pump out to get the vacuum drawn initially to start things up.

At that point, it's not clear to me what else you leave on the table as compared to a high end vacuum system - but I have never worked with maple vacuum systems, so maybe I'm missing something.

[Snowy Pass Maple]

If you are talking about just going down the shelf, I don't think this will be a problem. I have something similar in my setup with all of my trees on a sloped area that ends with a 30 foot drop-off. The tubing can span 75 or 100 feet without any problems - you'll want to find a way to keep it tight.

If you avoid leaks, you will get really good vacuums at the taphole with those kinds of drops.

I'm wondering why you mention keeping it tight. Our final 250 foot run to build the vertical drop is just laying on the ground. Most is sloped, but I'm sure I have a dip here and there - I didn't worry about it as much as our 5/16 setup. My thought is that the sap loads up and moves so fast in a plug flow pushing everything through that sags may be much less of a concern than with 5/16 where they can harbor stagnant sap?

[Dave Lister]

I think the ultimate combo would be to combine one of these diaphragm pump setups with 3/16" tubing and enough control logic that could use the pump to get the flow started and then switch itself out of the way once the sap is running and vacuum is achieved - which would also greatly extend the operating or battery life in a remote application.


I was curious if “priming” the line by pouring a gallon of water into the top of the line after you put your last tap in would get everything flowing sooner?
The line is so small, it wouldn’t take a lot of water to fill the entire length of a 1000 foot long run of tubing, and then, all of the trees would immediately be on vacuum. All you would need to do is wait for the thaw and you’d be in business. With check valves, you wouldn’t even have to worry about the water going back into the tree hole.

[bowhunter]

Colin,

Thanks for the info on the fittings. I e-mailed the Shurflo tech group and it doesn't sound like their 120 volt motors will last very long....definitely not continuous service. They said they wouldn't expect a pump to last more than 3-4 months in continuous service. It didn't sound like they expected their 12 volts to do any better. I guess I'll check the Aquatec pumps again.

[Snowy Pass Maple]

I was curious if “priming” the line by pouring a gallon of water into the top of the line after you put your last tap in would get everything flowing sooner?
The line is so small, it wouldn’t take a lot of water to fill the entire length of a 1000 foot long run of tubing, and then, all of the trees would immediately be on vacuum. All you would need to do is wait for the thaw and you’d be in business. With check valves, you wouldn’t even have to worry about the water going back into the tree hole.

Interesting idea... I can't imagine why it wouldn't work. And thinking back a little more on this, I'm not even sure if this is a problem after the first run, because I often noticed a lot of sap sitting in the line when frozen, so maybe that alone is enough to get the vacuum primed again on a thaw.

[Snowy Pass Maple]

Colin,

Thanks for the info on the fittings. I e-mailed the Shurflo tech group and it doesn't sound like their 120 volt motors will last very long....definitely not continuous service. They said they wouldn't expect a pump to last more than 3-4 months in continuous service. It didn't sound like they expected their 12 volts to do any better. I guess I'll check the Aquatec pumps again.

Yea, Aquatec definitely has models rated for continuous duty. Their website has some PDF files that show this and it is based largely on temperature rise which is a function of current draw that is determined by pumphead type and pressure.

[ryebrye]

Interesting idea... I can't imagine why it wouldn't work. And thinking back a little more on this, I'm not even sure if this is a problem after the first run, because I often noticed a lot of sap sitting in the line when frozen, so maybe that alone is enough to get the vacuum primed again on a thaw.

Yes, it definitely is enough. I would check my lines after thaws and they would be back to high vacuum very shortly after the lines thawed. One of my lines has a small leak somewhere I can't hunt down - it is the only one that ever drains out completely. The other two have had a full column of sap - frozen or thawed - since mid march.