Drilling for thread grafts? Prevent wood burn?

[Scrogdor]

Kind of a novice when it comes to thread grafting. I had a dremel with a drill bit attachment, but the hole started smoking so I stopped. What is the correct rotations per second and type of drill bit to use to prevent friction smoke?

 

[TomB]

Use a proper wood drill bit, at the slowest speed possible. Start the hole from the side where the whip will exit.

 

[Scrogdor]

Use a proper wood drill bit, at the slowest speed possible. Start the hole from the side where the whip will exit.

12 Inch Brad Point Drill Bits for Wood (Pack of 10) https://www.amazon.com/dp/B0889GX44G/ref=cm_sw_r_cp_api_i_YTW74Y2ZA8PNYBZ2TAM8?_encoding=UTF8&psc=1

 

[Dav4]

Agree with @TomB about using a proper drill bit. A good drill bit will almost pull itself through the wood. If the trunk or branch is thick, the bit will load up with wood and you'll need to back out periodically to free the bit from collected saw dust or else it won't cut well. Slow and steady, let the tool do the work without pushing too hard will get it done right.

The bits you have should do the trick though I've never seen a drill bit tip like that... what are you drilling through and when does it smoke?

 

[Scrogdor]

Agree with @TomB about using a proper drill bit. A good drill bit will almost pull itself through the wood. If the trunk or branch is thick, the bit will load up with wood and you'll need to back out periodically to free the bit from collected saw dust or else it won't cut well. Slow and steady, let the tool do the work without pushing too hard will get it done right.

The bits you have should do the trick though I've never seen a drill bit tip like that... what are you drilling through and when does it smoke?

Trident maple, it smokes about half way through.

 

[Dav4]

Trident maple, it smokes about half way through.

So, the bit cuts well until half way through... Are you periodically backing out to free the cutting edges of the drill bit from debris?

 

[19Mateo83]

Coming from a carpenter, those Brad point bits should do the trick. Clearing the shavings periodically is a must with those, the slower you can drill the better.

 

[Scrogdor]

I wasn’t clearing the saw dust out. Also ordered some of those bits which will be here tomorrow.

 

[misfit11]

Good call on getting new bits. They should be sharp enough to go through easily. Drilling on live wood is definitely different than on on 2X4 or something.

 

[misfit11]

When you insert the branch, put it in as far as possible so it's nice and snug. Apply cut paste at both sides of the grafts.

 

[Scrogdor]

When you insert the branch, put it in as far as possible so it's nice and snug. Apply cut paste at both sides of the grafts.

I don’t have to expose the cambium correct? From what I’ve seen on YouTube it should just grow into the branch?

 

[Dav4]

I don’t have to expose the cambium correct? From what I’ve seen on YouTube it should just grow into the branch?

No, but using a matchstick to wedge the graft to the top of the hole on the exit side will help the graft take.

 

[misfit11]

No, but using a matchstick to wedge the graft to the top of the hole on the exit side will help the graft take.

Never heard of this trick. I'll have to try it.

 

[River's Edge]

Kind of a novice when it comes to thread grafting. I had a dremel with a drill bit attachment, but the hole started smoking so I stopped. What is the correct rotations per second and type of drill bit to use to prevent friction smoke?

I do a lot of thread grafting in older material. have not found the speed of the drill bit to be a problem. it did take some time to find longer bits and smaller diameter bits to fit the drill. Not expensive though because they are easily found in second hand stores for some reason. Big advantage to the older style is the length of the drill bit and control over the speed. Allows one to carefully execute entrance and exit. I advise starting from the exit and proceed to the entrance. Also plan the angle and the direction of the exit for the design ahead of time. With planning the entrance hole can easily be on a different plane and not exactly opposite.
I often drill two sizes for lengthier thread grafts to accommodate the thinner apical end and the thicker portion further back. Much better results if a smaller exit hole to match the exiting portion of the scion very closely in the beginning of the grafting process.

 

[19Mateo83]

I do a lot of thread grafting in older material. have not found the speed of the drill bit to be a problem. it did take some time to find longer bits and smaller diameter bits to fit the drill. Not expensive though because they are easily found in second hand stores for some reason. Big advantage to the older style is the length of the drill bit and control over the speed. Allows one to carefully execute entrance and exit. I advise starting from the exit and proceed to the entrance. Also plan the angle and the direction of the exit for the design ahead of time. With planning the entrance hole can easily be on a different plane and not exactly opposite.
I often drill two sizes for lengthier thread grafts to accommodate the thinner apical end and the thicker portion further back. Much better results if a smaller exit hole to match the exiting portion of the scion very closely in the beginning of the grafting process.

Damn I wish I could find old school brace drills at thrift stores!

 

[River's Edge]

Damn I wish I could find old school brace drills at thrift stores!

They are usually lying on the bottom of the older tool box's under the wrench's and screw drivers. Occasionally someone has grouped them together in a bin and is charging $1or$2 each for them. Flea markets are another good source for older used tools. Keep in mind that often a thrift store will disguise itself as an " Antique Store" and vice versa. Basically there is limited demand for Armstrong tools so they should be cheap. I have picked them up ll over Canada and the western USA. Best locales seem to be around "retirement communities" for some reason. Places where older people move and then have to downsize.

 

[Scrogdor]

Alright! So I got the hole through and managed to get the whip through. I may….. have cracked the whip while securing it with wire though . Was definitely more difficult then it looks in the videos.

I need to rethink my order of operations. There was just enough space to have a bud on each side, but made it difficult to get them both so one wasn’t being pulled inside the tree. I’ll know pretty quick If the other half dies

 

[BonjourBonsai]

have cracked the whip

Don't let Devo know!

 

[River's Edge]

Alright! So I got the hole through and managed to get the whip through. I may….. have cracked the whip while securing it with wire though . Was definitely more difficult then it looks in the videos.

I need to rethink my order of operations. There was just enough space to have a bud on each side, but made it difficult to get them both so one wasn’t being pulled inside the tree. I’ll know pretty quick If the other half dies

Never followed a video but it helps if you wrapped the buds and scion before pulling through the hole. that way the wrap takes the rub and the buds remain unharmed. Grafting tape works well for this, If you cracked the thread graft the odds are not good. The difficulty increases if one drills a smaller hole than needed to fit comfortably. The key is to stage the hole to take the small portion and then as the branch diameter increases it tightens up as it is pulled through. The diameter change may be small but it is real and can be measured ahead of time.
ns

 

[Emanon]

Coming from a carpenter, those Brad point bits should do the trick. Clearing the shavings periodically is a must with those, the slower you can drill the better.

Would a brad point bit be better than an auger? Maybe that's because it might be easier with the brad to keep the diameter of the hole small enough for the whip (smallest auger I have seen is 1/4")? But an auger would help keep debris clear.