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Alternative to Auger for Drilling 1.25" Hole in Live Tree?

markz528

Hot Rolled
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Sep 25, 2012
Location
Cincinnati
I am trying to help a startup with some technical challenges around powering their setup and was hoping there might be a better alternative than an auger to drilling a 1.25" diameter hole 6 inches deep in healthy live trees. Requirements is it needs to be very efficient (every second counts) and it can't burn the wood.

Proof of concept is done and now building the first prototype so we still have flexibility. The holes will be drilled by a robot and the preferred robot cannot handle an auger. Will go bigger if have to, but was trying to figure out if some other cutting tool might be better suited that would potentially cut at a higher rpm. The auger cuts at 800 rpm. I know that chip evacuation might be impossible with live tree chips but I figured I would at least explore options.

For starters we are looking at making roughly 900,000 holes. They will be used to extract sap from the trees.

Anyone have any thoughts?
 
For starters we are looking at making roughly 900,000 holes. They will be used to extract sap from the trees.

Anyone have any thoughts?
Why would you not doo what all the other maple syrup producers doo ?
Or are you tapping something else ?
 
It is not maple syrup. For the process, the robot will drill the holes, insert pvc pipe pieces, inject acid, cap the pipes and harvest when ready. Right now on a much smaller scale they use an owl auger.
 
It is not maple syrup. For the process, the robot will drill the holes, insert pvc pipe pieces, inject acid, cap the pipes and harvest when ready. Right now on a much smaller scale they use an owl auger.

What species of wood ?
Have you checked with the Forrest Products lab ?
 
High-rpm spade bit, with compressed air chip removal. I imagine it will be a tree-hugging robot, so it can push fairly hard.

A robot holding a Milwaukee Hole-Hawg right-angle drill, with a Milwaukee Switchblade Self Feed Bit (or their standard self-feed) would do the job, and the robot would just need to hold the drill motor. Right-angle drill offers decent leverage, which could even be transmitted to the tree itself with the proper mechanism. Would need to 'peck' drill, since chip evacuation is not automatic like with a spade bit. Multiply by a million and spade wins out...
 
It's greenwood, so clogging the auger is an issue.

Those big bandsaws used to turn green logs into raw planks to be dried are lubricated with kerosene (usually diesel fuel).
 
I drill hundreds of holes in oak logs to inoculate them with shiitake spawn. The bit I use is a modified auger type mounted to a angle grinder (low torque, high RPM 10,000). The diameter is smaller than you need though at only 12mm, but it is effortless and incredibly fast. Essentially as soon as the tip hits the log it bottoms out. Here is what they look like. Maybe this will help? Maybe you could grind a larger bit to match?
It sounds like your robot is torque-limited in this application? Maybe a less aggressive screw tip so it doesn't pull into the wood so fast?

Here's a YouTube video to see how fast it is
New drilling solution for shiitake inoculation - YouTube


tools-mushroom-log-drill-bits-28415795953766_2000x.jpg
 
They are freshly cut limbs, drilled into the side, no different than drilling into a trunk other than his hole diameter and depth
what's your point?
watch the video

My "Point" was who would drill into, and then inject acid into a "Living Tree" ?

You quoted me, like you had an answer, which you doo not.

My "Question" to YOU about "End or Side" was for the drill bit recommendation.
Qty (2) different ways of drilling.
 
My "Point" was who would drill into, and then inject acid into a "Living Tree" ?

You quoted me, like you had an answer, which you doo not.

My "Question" to YOU about "End or Side" was for the drill bit recommendation.
Qty (2) different ways of drilling.

My first post addressed the OP question, not yours, and had no quotes in it.
You responded to my first post suggesting that drilling into oak "LOGS" is somehow different than trees. I never quoted you about your acid question. I offered a suggestion to the OP about a drill bit I use for a similar procedure.
and I did answer the side/end question
 
My first post addressed the OP question, not yours, and had no quotes in it.
You responded to my post suggesting that drilling into oak "LOGS" is somehow different than trees. I never quoted you about your acid question. I offered a suggestion to the OP about a drill bit I use for a similar procedure.

My mistake, you in fact did not quote me originally, need to use my glasses more.
 
Start with a Silver & Deming 1 1/4" bit. Re-grind it to a brad point. Torque to drive it will depend on hard you push it. You may need to peck to clear chips. It may help to reduce the OD of the drill behind the cutting edge to reduce sidewall drag.
 
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Could be that a parabolic flute drill could be custom ground to find a happy medium in terms of chip evacuation, required torque, and fast speed of drilling given whatever hp you can put into the cut. Compared to an auger bit it should last longer and be less variable in terms of stalling when the screw point hits a snag.
 
I drill hundreds of holes in oak logs to inoculate them with shiitake spawn. The bit I use is a modified auger type mounted to a angle grinder (low torque, high RPM 10,000). The diameter is smaller than you need though at only 12mm, but it is effortless and incredibly fast. Essentially as soon as the tip hits the log it bottoms out. Here is what they look like. Maybe this will help? Maybe you could grind a larger bit to match?
It sounds like your robot is torque-limited in this application? Maybe a less aggressive screw tip so it doesn't pull into the wood so fast?

Here's a YouTube video to see how fast it is
New drilling solution for shiitake inoculation - YouTube


View attachment 340898

That video is impressive!

Where do those bits come from?
 








 
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