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Are standard drill bits a taboo?

Posted: Sun Jan 06, 2013 7:33 pm
by zanthal
I've consulted the wiki, and it looks like chamber and even mortise and draft hole drilling call for specialized drill bits. If I had my choice I'd probably go with Forstner bits for the mortise and bur bits for the chamber.

But right now I don't have my choice, will have to purchase those bits later.

So my question is, are standard straight steel drill bits a no-no? If so, why exactly?

It is appreciated. :)

Re: Are standard drill bits a taboo?

Posted: Sun Jan 06, 2013 8:42 pm
by Sasquatch
Twist drills will work fine in the mortise.

For the chamber.... well... have you ever looked inside a pipe? Smooth cone-ish sort of shape works good and allows some shaping on the walls of the the pipe that a big flat ended shape just won't.

Re: Are standard drill bits a taboo?

Posted: Sun Jan 06, 2013 11:21 pm
by andrew
Burs come in all sorts of shapes. Unless you buy a nice carbide one you will dull it. They are very slow cutting by reputation. I don't have one myself. Spade bits were easier and cheaper. Just shape them on a bench gringer from harbor freight.

Re: Are standard drill bits a taboo?

Posted: Mon Jan 07, 2013 11:51 am
by wmolaw
andrew wrote:Burs come in all sorts of shapes. Unless you buy a nice carbide one you will dull it. They are very slow cutting by reputation. I don't have one myself. Spade bits were easier and cheaper. Just shape them on a bench gringer from harbor freight.
:clap:

Re: Are standard drill bits a taboo?

Posted: Mon Jan 07, 2013 12:21 pm
by caskwith
A burr also doesn't have the chip clearance needed for drilling.

Re: Are standard drill bits a taboo?

Posted: Mon Jan 07, 2013 7:52 pm
by pipeguy
Burrrrrrrr its cold in New England :lol:

Re: Are standard drill bits a taboo?

Posted: Mon Jan 07, 2013 10:52 pm
by zanthal
It's cold for California about now too.

Thanks for the tips about bur bits.

Re: Are standard drill bits a taboo?

Posted: Tue Jan 08, 2013 12:48 am
by AlanP
andrew wrote:Burs come in all sorts of shapes. Unless you buy a nice carbide one you will dull it. They are very slow cutting by reputation. I don't have one myself. Spade bits were easier and cheaper. Just shape them on a bench gringer from harbor freight.

This. I'm still super green when it comes to pipe making, but making a chamber bit is really easy, and spade bits are cheap if you mess up.

Re: Are standard drill bits a taboo?

Posted: Thu Jan 10, 2013 10:31 pm
by zanthal
I'm thinking that it's better to drill the draft hole BEFORE the mortise, is there an argument either way for this?

Re: Are standard drill bits a taboo?

Posted: Thu Jan 10, 2013 11:09 pm
by Sasquatch
Occassionally it is advantageous to do this, but only occassionally. I mean, you have a pretty good ability to control where your hole is if you drill your mortise first - you can see exactly what you are doing.

IF you have an airway that is really gonna be off kilter, it can be nice to sort of chase it down and positition it by adjusting the mortise depth. But I've only done that on a half dozen pipes. It's just faster and easier to do the mortise first, tap a little pilot hole dead center, and then do whatever else needs to be done.

The disadvantage of doing the airway first is that on a pipe with only a slight bend, the mortise will tend to follow the airway hole, and that's bad.

All in all, I would do the mortise first 99% of the time.

Re: Are standard drill bits a taboo?

Posted: Fri Jan 11, 2013 12:16 am
by The Smoking Yeti
As Sas says, it does depend. I often times do an airway first, but I'm gonna rethink things and start doing mortise first again. The way I avoid the mortise following the airway is running a 5/32" pilot hole for the mortise first- I'm also shaping then drilling though, which changes things a bit.

Re: Are standard drill bits a taboo?

Posted: Fri Jan 11, 2013 2:44 am
by zanthal
you have a pretty good ability to control where your hole is if you drill your mortise first - you can see exactly what you are doing
that was how I was thinking about it.
the mortise will tend to follow the airway hole, and that's bad
Do I understand you right, that the mortise (and likewise, the draft hole of the stem) lining up parallel to the draft hole is bad? Is this because moisture will get up the stem easier while smoking?

Re: Are standard drill bits a taboo?

Posted: Fri Jan 11, 2013 2:58 am
by The Smoking Yeti
He means when you're drilling a bent pipe, your mortise is supposed to be at a different angle to the airway- if it follows the airway passage, it'll wander, and the whole mortise wont be properly aligned. It has nothing to do with moisture.

Re: Are standard drill bits a taboo?

Posted: Fri Jan 11, 2013 6:14 am
by d.huber
Sasquatch wrote:It's just faster and easier to do the mortise first, tap a little pilot hole dead center, and then do whatever else needs to be done.
Here's the key.

Re: Are standard drill bits a taboo?

Posted: Fri Jan 11, 2013 6:22 am
by caskwith
Airway first for me, I find i can't get a nice start otherwise on bent pipes.

Re: Are standard drill bits a taboo?

Posted: Fri Jan 11, 2013 1:24 pm
by taharris
caskwith wrote:Airway first for me, I find i can't get a nice start otherwise on bent pipes.
Mee too.

I get around the mortise wander issue be leaving about a half inch of scrap on the end of the shank that I trim off after the mortise is drilled, leaving a nice straight mortise.

Todd

Re: Are standard drill bits a taboo?

Posted: Fri Jan 11, 2013 2:25 pm
by wmolaw
Now I am totally confused. Not an unusual circumstance for me, however.

Re: Are standard drill bits a taboo?

Posted: Fri Jan 11, 2013 2:47 pm
by d.huber
wmolaw wrote:Now I am totally confused. Not an unusual circumstance for me, however.
There are a few methods laid out here. I think it important to choose which one works best for you.

Re: Are standard drill bits a taboo?

Posted: Fri Jan 11, 2013 3:02 pm
by caskwith
taharris wrote:
caskwith wrote:Airway first for me, I find i can't get a nice start otherwise on bent pipes.
Mee too.

I get around the mortise wander issue be leaving about a half inch of scrap on the end of the shank that I trim off after the mortise is drilled, leaving a nice straight mortise.

Todd
I use a carbide stub drill, no chance of wander with that! haha.

Re: Are standard drill bits a taboo?

Posted: Sat Jan 12, 2013 7:00 pm
by zanthal
Does anyone have experience with countersink bits for chamber drilling?

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