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how do I drill out a 3 and 1/8th hole in thick wood?

Take your board, drill a pilot hole (use the same size of drill that your hole-saw uses for a pilot hole, or even one size smaller than the hole-saw for each large hole in the spot you want it, mark the board so you know the orientation, then rip your board on a bandsaw into three or four pieces, then using your hole-saw and the pilot holes you have drilled cut out the larger holes. Get the orientation of the boards right, glue the whole thing up and no one will know you ever ripped the board down to start.
 
Oh yeah, 620 RPM is still rather fast for that big a hole saw, any way you can slow that sucker down?:huh:

Also if you try my method, make the board wider too, so when you are doing the hole-saw thing, the whole hole-saw is in wood, none of it is blowing out the side of the wood, then when you are done, rip the piece of wood down to get the gap you want.

Neat idea Allen, you come up with some good ones!

BTW, I hope your finger heals fast!
 
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hard to admit, Im not a fan of the bandsaw.
I cant seem to bring myself to use it much, fearing the blade always so close to my shaky hands and poor vision.
I have a bunch of new ellis blades, just waiting to cut, but Im not sure if my comfort/fear factor will allow me to work on it.
I feel more at ease with a bit spinning than a blade slicing. Not sure why, its a mental thing.
The prototype was cut, so its no longer here, gone in the trash, but I have enough ideas to procede with glueing up walnut to make a rack or two.
I appreciate all the ideas. I will reread this thread a few times and take notes as I usually do and pull out what I feel I can do and do comfortably.
with the weather changing I need to finish off the pantry/linen cabinet, and a few other small things Im working on since I need to spray lacquer on them, and I cant keep the garage warm enough in cold weather.
 
Making large round holes for cheap clock inserts I learned a trick... A combination of Carol's idea, either to get the template hole, or for production use. This trick expands a hole 3/4 inch at a time, so for 3 1/8" start with a 2 3/8 inch Forstner bit, or do it twice after starting with a 1 5/8 inch Forstner bit.

Take a rabbeting router bit, which typically cuts a 3/8 inch rabbet based on a guide bearing. Set the depth of cut fairly deep, but be sure the rabbet guide bearing follows the bottom of the drilled hole. After you cut all the way around you have hole where the top is 3/4 inch larger than the bottom (3/8 inch on each side). Use a pattern bit (guide bearing on the top) to cut the bottom of the hole the same as the top. If you are cutting all the way through you could flip the work over and cut from the bottom with a flush trim bit (guide on the bottom rather than the top) - fine for this project but not if you are making a clock.

With a deep cut like this, you probably want to do part of the hole from the front and the rest from the back, so the pattern and trim bits are not as long, and less subject to strain and wobble.
 
Brent Dowell said:
What speed were you running that big ole forstner? It shouldn't be going that fast. It probably needs a good sharpening though.

I'd think a hole saw like Chuck used on his mugs would be a good way to go. He was drilling holes 7.5" deep.

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I don't get it, but that's nothing new. :eek:
The cutter shown is a lot less than 7.5" so it won't bottom. It will cut about a 4" deep circle around the center of the hunk of wood. How do you get that plug out? How do you finish cutting to 7.5" and then get that plug out? :huh:
 
Same as with the hole saw, but this one is a little deeper and I believe would give a finer cut.

Back it out, chisel out some of the waste, go at it again from the same side, or flip the work piece over and get it in two tries..
 
Ahh, perhaps that was the confusion. All I was posting that picture for was the hole saw, not the lathe part.
 
I didn't read all the posts.

Use a hole saw, just go the next size up from what you need.

When using said hole saw, a little trick I like to think I came up with, (pretty sure I did), is to use compressed air blowing into the cut. Either in from the side, or straight into the holes in the side of the hole saw as it spins. Cleans the debris out of the cut, and cools the saw. Works like frickin' magic. Something like this I might punch some holes all the way through with a paddle bit to let stuff fall out. That is if you are planning on doing it where you will cut into your holes after they have been drilled.

Seriously, the air thing works awesome.

Now, the hole saw is going to bottom out. Just take a spade bit and paddle out as much of the material as you can. Think about this a bit, as you want to leave as little as possible. Then just use a pair of pliers to break, rip, tear out the stuff in the middle that is now in the way.

Rinse and repeat.


(edit)- Just read through some of the posts..... Mother of god you people can make things complicated.
 
I think the forstner bit is still your best bet. nice and sharp and at slow speed as was recommended but also frequent chip clearing. I have also found running the shop vac close to the hole helps keep the bit a smidge cooler while its clearing the chips. back the bit out of the hole, clear, drill a little, back it out etc etc. 250 to 350 rpm is probably a good range of speed.
 
yeah, the forstner bit was under 30 dollars, but it will not cut through walnut with my drill press.
I tried every speed, making sure the belts are tight, light touches and then withdrawing, hard driving, nothing works.
The bit sticks.
Im going ahead and ordering a bit similar to what chuck uses to drill out the mugs.
Its a hole saw, but not so many teeth, made for hardwoods.
If that doesnt work with my drill press, Ill either have to find someone near me with a more substantial drill press, or perhaps charlies way would be most accurate.
I put the self feed bit into my drill, just to see how anyone could make a hole that size.
In sheetrock, yeah, easy, but in plywood, bit wont do it, and then again, maybe I need a real powerful drill, but my driver drives 3/8 inch lag bolts into 2x4s, so I dont think its that underpowered.
seems I get to a point, since I use 1.5 inch, 1.75 inch forstners, and go through anything, but that wide bit, just wont happen for me.
 
well, the second prototype is finished, didnt want to waste time making it out of scrap wood, so I glued some scarf joints and used some real mahogany for the post, and some spanish cedar for the base, 3 coats of waterlox original, one coat of waterlox gloss, but I need to sand down the last coat, didnt lay right, I think me leaving the window open in the room, the cold temps, the old oil, Ill sand and wipe on a coat today.
I decided to make the holes a bit larger to accomodate larger bottles, but I wont do that again, not happy with the look.
It was basically a failure, since this should be a simple build, and use a simple forstner to cut the holes, not struggle with a hole saw and then (I believe ken mentioned it first) drill through hole and flip and use hole saw on other side.
Uh uh. time consuming, and my cruddy little table top drill press is not up for the job.
I have a few designs of this simple wine rack with s shapes to mount with metal french cleat on a wall, arch shaped for floor, but until I have use of a powerful drill press that will push the forstner through, Ill will abandon this project, and move on.
 

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Like the others, I would use the hole saw. I would drill in about an inch and half, use a chisel to knock out the middle and then drill some more. Drilling that deep with a hole saw will create some problems. To keep the heat down, you need to get rid of the chips. Use the hole saw to mark out your hole size and then switch to a 1" bit and drill a couple of holes just inside so that the chips from the hole saw have someplace to go. The edge of the smaller bit should be even with center of the kerf of the hole saw. By giving the chips an exit, you won't have the heat build up.
 
Allen,
I didn't read every reply to your post, so this may have been said.... but if you're using a forstner that size, I would recommend you drill in steps....use progressively larger bits until you get to where you want to be.... to ensure you don't mis-align your cut, cut a pilot hole about 1/4 inch deep where you'll want the final cut, then start with maybe a 1 inch or so and work your way up to the 3 1/8"....
 
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