drill bits sizes
Hello Kinya I have been doing some research on drill bits sizes. And I was wanting to know if this sounds right to you. So that way I can go into a normal hardware store and not have to special order stuff and wait. The reason I am doing this is because I was looking at my Dremel drill bits and the look really close.
(14145TD) #55 = 3/64 drill bit
(14144CD) #52 = 1/16 drill bit
and am pretty sure am going to have to special order the (14145T) 0-80 tap.
When tapping reedplates I dip the tap in a small jar of mineral oil. Also to help the tap keep from binding screw it in a small amount then back it out. Continue tapping the hole this way until the tap runs smoothly. Another bonus using the mineral oil is that it removes the shavings of metal from the tap. That's the reason to use a small jar. The shavings collect at the bottom of the jar. I also tap the screws holes that are in the draw plate so the run freely. The harmonica manufactuers use self tapping screws to attach the reedplates to the comb and sometimes they will bind somewhat. Use mineral oil and a tap and when you put the harp back together they'll be easy to screw in and you'l be able to control how much you tighten them.
Awesome tip Jon!
... mineral oil is good for other purposes besides treating constipation ;o)
Your Harpsmith, Kinya
Hi JF
It is sooo close, but not the same ...
For the 0-80 (#52) reed pad clearance hole, your 1/16" might be a tad too small (tight for the 0-80 machine screw), and the next fractional size bit up would be too large at 3/32". An alternative to the #52 drill bit, would be investing (lasts forever) into a set of reamers. With a downward turning motion, the sharp corners of the reamer will be able to create the desired hole size. The deeper the tool, the larger the hole.
Tip: for predictable results, scribe (Sharpie permanent marker pen) the prefered depth of the tool onto the reamer shaft.
:
This set of 6 sizes are on sale for $18.75 at http://www.micromark.com/micro-size-precision-reamers-set-of-6,6759.html
For your reed plate #54 to #55 pilot holes, the 1/16" bit will work, but be warned; the 1/16" hole might be little tight for the 0-80 tap. Use caution--forcing a tap could snap it inside the reed plate hole. Attempting to remove a broken tap from a harmonica reed plate is opposite of fun ;o(
All tools are still on sale at <www.micromark.com> Individual drill bits cost $1.65 each
Your Harpsmith, Kinya