Drilling technique question

[Jonnyp390]

Hey y'all, is there an agreed upon best practice for drilling a tap hole?. I bought a real tapping bit last year and it seemed to do a great job, but I still wonder whether it is better to;

A) drill the hole with the bit spinning the whole time, both in and out
Or
B) drill the hole with the bit spinning on the way in, stop the bit from spinning, then pull straight out.

Last year I tried using the technique described in option B, but it seemed that some of the holes seems a little ragged and I reamed them again to make sure they were clean.

Or am I just way over thinking this because I really want to be in the woods drilling said tap holes instead of looking at forecast of -20 for the next two nights.

[Thompson's Tree Farm]

In and out with drill spinning

[jmayerl]

Drill spinning both in and out. Also 90 degrees to the tree( no upward slope)

[TerryEspo]

I am about to learn something I think.
No upward slope at all?
Not the slightest upward angle?

Thanks.

Terry

[jmayerl]

Nope none.....when sap is running the tree is under pressure (8-12 psi). Drilling at a angle only encourages a oblonge hole that will leak. Always drill at a 90!

[mapling4fun]

Last year I did option B and got the same results, holes were ragged. Going back to spinning in and out
Never heard of the 90 degree to tree. I had read to put a slight upward angle to help with flow, maybe that wasn't correct

[adk1]

I have been told for non vac a slight upward angle, with vac straight in.

[jmayerl]

I have been told for non vac a slight upward angle, with vac straight in.
Again, the sap exiting a tree under any condition with any tap is under quite a bit of pressure so no need to angle any hole as that will just lead to a oblong hole that could leak.

[maplwrks]

If you are tapping buckets, you should tap on a slight upward angle. Tapping tubimg is different, you want to drill straight in to get the roundest hole.

[NW Ohio]

The Maple Syrup Producers Manual suggests that you should "Slant taphole so the back of the taphole is slightly higher (approx. 10 degrees) to minimize sap collecting in the taphole between runs." The picture that goes with that caption shows tubing running between trees in the background and doesn't mention doing it differently for vacuum or not. I have always tipped mine slightly. My logic (which admittedly is often flawed) is that if sap sits in a flat tap hole and freezes it could expand and push the tap outward, although I don't know if that is a real concern.
I wonder if the best question might not be "which is correct?" but instead "which do you prefer?" or even "how did your grandad do it?"

[maple flats]

I'm with NW OHIO. This is the first time I ever heard that you should not slope up a little. I don't see how a sloped hole will cause a leak as long as the bit enters and leaves the hole spinning and without wobble.

[adk1]

The Maple Syrup Producers Manual suggests that you should "Slant taphole so the back of the taphole is slightly higher (approx. 10 degrees) to minimize sap collecting in the taphole between runs." The picture that goes with that caption shows tubing running between trees in the background and doesn't mention doing it differently for vacuum or not. I have always tipped mine slightly. My logic (which admittedly is often flawed) is that if sap sits in a flat tap hole and freezes it could expand and push the tap outward, although I don't know if that is a real concern.
I wonder if the best question might not be "which is correct?" but instead "which do you prefer?" or even "how did your grandad do it?" Exactly, that is where I originally heard from. I do however understand drilling straight in will provide the roundest hole or less oblonged.

[WESTMAPLES]

I drill mine full throttle in and out with a slight angle (10 degrees or so) some people over think the actual drilling of the hole, its like shooting skeet either you have good aim on the fly or you don`t . im a contractor with lots of trade hours, so its just whip it out and drill it straight in/out no oblonging then repeat one fluent motion practice on a dead tree or piece of firewood ( just not with your good tapping bit )

[Helicopter Seeds]

Still new to syrup making, but not new to math and geometry.... Straight in, wether angled up, down, sideways, will not cause an oblong hole. The 'intersecting plane' of the hole may appear oblong, but since it also interfaces with the same oblong interecting plane on the tap, it is a perfect fit.

I learned last year slight upwards, it worked, so that is what I did this year.

[jmayerl]

Just follow the science of the matter, not the old school thinking of generations past.....

[Big_Eddy]

Still new to syrup making, but not new to math and geometry.... Straight in, wether angled up, down, sideways, will not cause an oblong hole. The 'intersecting plane' of the hole may appear oblong, but since it also interfaces with the same oblong interecting plane on the tap, it is a perfect fit.

I learned last year slight upwards, it worked, so that is what I did this year.

Correct. But as a tap is tapered, the intersection with the plane is at a slightly different diameter top versus bottom. The shape of the angled plane through the round tap hole is not an exact match for the same plane angle through a tapered tap.. That said I angle upwards slightly on buckets. My thinking is that when the sap stops flowing the tap hole will drain better and therefore sap will not freeze behind the tap and push it out.

[WI Sugarpop]

If you drill an angled 5/16" hole in a piece of wood and drive a 5/16" dowel in the hole and then cut off the part of the dowel that is sticking out, and then sand it flush, the hole will be filled in solid with out a crack around it. So it would be with a tap drilled in at a slight angle.

[DrTimPerkins]

The most important technique to drilling a taphole for high yield is to first be sure that you're tapping a maple tree. :)

As for the angled or slight angle....it really doesn't matter a great deal which camp you choose to follow (for tubing). Geometrically a slight angle will not result in an oblong hole. We tap with a slight upward angle here at UVM PMRC. The main thing is to choose the right spot to tap (not near an old taphole, especially if you're on vacuum), to be steady when you drill, to use a very sharp bit, and drill with full power in and out.

[Galena]

Wow, had no idea that drilling a hole could be so complicated! I just use a brace and bit. After the spiles are pulled I keep a close eye on the holes to ensure that they're healing well. So far, so good.

[DoubleBrookMaple]

If you drill an angled 5/16" hole in a piece of wood and drive a 5/16" dowel in the hole and then cut off the part of the dowel that is sticking out, and then sand it flush, the hole will be filled in solid with out a crack around it. So it would be with a tap drilled in at a slight angle.Very good example!
I was told just yesterday to drill straight by a local pro I was chatting with. I didn't completely buy the oblong hole theory, but drilled some straight yesterday. Not necessary. The only result difference is that you have a trace longer circumference with an elongated entry. Remember, the hole is not truly elongated, only the entry pattern. I will say, the longer entry line may increase the chances of a defect, but I think insignificant. I'm going back to a slight angle down to straight, in order avoid an upward slope.

[Helicopter Seeds]

Correct. But as a tap is tapered, the intersection with the plane is at a slightly different diameter top versus bottom. The shape of the angled plane through the round tap hole is not an exact match for the same plane angle through a tapered tap.. That said I angle upwards slightly on buckets. My thinking is that when the sap stops flowing the tap hole will drain better and therefore sap will not freeze behind the tap and push it out.
Got a point there, the tap has a slight conical taper, so correct after all. The very end will be an egg shape, larger at the bottom if tap hole is slightly upward. On slight angles, cosine close to 1, this won't mean much. Also noticed that the tap cone may not be constant. Seems to have ribs that get bigger, but not as much the closed section.