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I just started using a 7/8" tobacco chamber drill bit from PIMO and it is taking way too long. It seems to be only burning the briar even though i take it very slow. Am i doing something wrong? I prepped the hole by first drilling a 5/32" guide and i am using the slowest speed

Make sure you are drilling clockwise!

More info! Are you using a lathe or a drill press? I would suspect the culprit is too many rpms.

hahaha I am!

Drill press. I have it at 500 at the moment

the pimo tool isn't great, I would drill it atleast half way with a forstner bit when I used them

rev

ahh thats bullshit that i spent $17 on this drill bit and it wont even drill....

what are some good tobacco hole drill bits and where can i get them?

Cornelius wrote:ahh thats bullshit that i spent $17 on this drill bit and it wont even drill....

what are some good tobacco hole drill bits and where can i get them?

I bought two of them, and they worked perfectly. After that, I've been making my own, and they work well also.

Must admit, however, I have ALWAYS used a forstner bit to drill the first part just so there was no issue of wobble with the altered spade bit. Just makes sense, at least to me.

Re shaped spade drills need regular sharpening to cut well.

alrighty im figuring it out. sorry about that guys

caskwith wrote:Re shaped spade drills need regular sharpening to cut well.

Hello everyone ,
time to enter in your group,
could anyone show us how we reshape the pimo chamber drill bits?what number of sand paper we must use?In which point of the drill bit we must sand it?
Thank you

How do I sharpen a tobacco hole drill bit?

I don't know how some of the other fellows do it, but use a fine file b4 every drilling and run the file on the relief edge until it looks smooth with no knicks and then I run it flat against the cutting side to knock of any burs or jagged edge I may have caused

honestly if you have a bench grinder it is pretty easy to shape your spade bit into a good taper for a tobacco chamber, like the rest of pipe making practice makes perfect

I tried to sharpen it with a dremel but it still doesnt seem to drill. i did end up drilling about 2/3 of the chamber with a forstner bit so now there is just this really frustrating centimeter of drilling left for the chamber drill.

gahh this is very annoying....

I, too, drill most of the way with a forsner bit. The Pimo bit just scoops out the bottom. If it's common for the Pimo bits to dull quickly, I wonder if they are sometimes overheated while being reground. Overheating destroys the temper, and the metal will no longer hold an edge. It's easy to do on a grinder, but really hard to undo.

Normal spade bits are usually too hard to cut easily with a file. If you can use a file to resharpen the bit, then I'll bet it's been overheated. Only thing to do is to keep resharpening it regularly, or grind one yourself without overheating it.

I have yet to sharpen my Pimo bits, but my 3/4" bit is already seeming dull after 6 pipes or so. I think I'll try sharpening it on a whetstone before I attempt to do it on powered equipment.

if your spade bit is sharp and the steel hasn't been annealed by burning it black on a bench grinder you can drill all day without sharpening
.. unless you're hitting nails in the briar? easiest way i've found to sharpen them is light even passes on a soft wheel on bench grinder. hold it steady with both hands and make the first pass just shy of the cutting edge to get the angle right etc. there's a whole grading system for grinding wheel grit and hardness for different materials, my local hardware store had 2 kinds the general purpose one and a one that's for sharpening carbide tools which is the one i use for drill bits and chisels. use a dremel for sharpening little forstner bits or would probably work well for a spade bit if you put either the dremel or the bit in a vise so you have 2 hands to make steady passes. you'll know if its sharpened right if a test hole doesn't make any funny grooves and there's no chatter or tear out

You shouldn't have any trouble with the bit, as long as a pilot hole has been drilled. I use a normal spade bit as pilot.
Are you sure the relief is right?
When sharpening (or shaping) on a benchgrinder, make sure to have the bit moving anti-clockwise (ie have the drill in reverse) and make sure that the angle that the bit forms with the grinding wheel, is right.

ahh isnt this supposed to be easy..?
I tried sharpening, but all i hear when the bit hits the briar is a whistle and absolutely no progress has been made.

Maybe i should just buy a new bit

Literaryworkshop wrote:I, too, drill most of the way with a forsner bit. The Pimo bit just scoops out the bottom. If it's common for the Pimo bits to dull quickly, I wonder if they are sometimes overheated while being reground. Overheating destroys the temper, and the metal will no longer hold an edge. It's easy to do on a grinder, but really hard to undo.

Normal spade bits are usually too hard to cut easily with a file. If you can use a file to resharpen the bit, then I'll bet it's been overheated. Only thing to do is to keep resharpening it regularly, or grind one yourself without overheating it.

I have yet to sharpen my Pimo bits, but my 3/4" bit is already seeming dull after 6 pipes or so. I think I'll try sharpening it on a whetstone before I attempt to do it on powered equipment.

This. When I make the bits, I hold them bare handed and when it starts to get hot to the touch, I cool it down and swap sides. Also, always grind with he way the bit cuts so you don't have to do as much sharpening up afterwards. If you don't kill the heat treat on one, they are hold their sharpness pretty well.

As for the guy asking how people made them. I just went and got some spades, drew the profile on with a sharpie ground each side back and forth and cooling it with a cup of water I had nearby if it got hot Once I got down to the sharpie, I started working on just one side to get it just how I wanted, then I traced the profile of that side on a piece of paper, and made the opposite side match that profile. It took a little while, but it works.

Cornelius wrote:I just started using a 7/8" tobacco chamber drill bit from PIMO and it is taking way too long. It seems to be only burning the briar even though i take it very slow. Am i doing something wrong? I prepped the hole by first drilling a 5/32" guide and i am using the slowest speed

To start with: Have you contacted PIMO with the problem? They would probably have some ideas as to what the problem is and help you correct it. It's possible you have a faulty bit but that's not the only problem.

At least part of the issue is those bits are not designed to drill the chamber in only one step. You need to drill out most of the hole before using them. Your pilot hole is too small. Step up a few sizes until you're close to the final diameter. Use a forstner bit the same diameter as your chamber bit to drill the top portion of the chamber. They make a much smoother hole than most other bits. Use your chamber bit only for the final shaping of the bottom of the chamber.
You should also increase your speed. Slow is good for forstner bits, you want to run your spade bit faster.
It does sound unusual to me that your bit seems to be removing almost no material. Are you spinning it the right direction? A backward spinning bit would cause the problem you describe.
The last time I had a spade bit that wouldn't cut well I realized that I had ground the edges backwards on it when I "sharpened" it. It has since been re-ground into a chamber bit with the edges going in the right direction and works fine.

Hope this helps,
Rodney