Drilling Your Own Flatwork: Bits?!

[verhoevenc]

Just curious as to where folks are getting the bits they're using to drill their flatwork, as the standard radii for rod magnets doesn't seem to match any standard bits? (Specifically the .195" ones is what's currently on my mind).
Chris

[Bruce Johnson]

Are you familiar with the standard "number" size drill bits? They are the standard US/English series of smaller drill sizes used in metalworking/machine shops. The largest is #1 (0.2280") and they go down to #80 (0.0135"). They're available through any machinery or tool supplier. Anyway, a #10 drill is 0.1935" and a #9 drill is 0.1960". Take your pick. Because the flatwork will probably spring back a little bit, the #9 drill will probably give you a sliding fit, while the #10 will give you a friction fit on a 0.1950" magnet. But, you'll have to try it and see.

[verhoevenc]

Never really used 'um (although I know they're out there) so it didn't even occur to me to check there. Great idea! Thanks!
Chris

[copperheadroads]

One if these charts come in handy sometimes
Number & Letter Drill Sizes With Metric Alternatives

[David King]

A 5 mm drill is right there as well.

[David Schwab]

I just picked up a 115 piece drill index. They are very handy to have. I was always looking for that perfect size bit for a job.

[Chris Turner]

Not to hijack the thread, but this is sorta related...

What is everyone using for flatwork material? I find that although I can use my mini table top saw on the black stuff you can get from StewMac, it seems like there should be an easier way to cut and shape the stuff. I'm gravitating toward perfboard, but is there anything else out there that's sturdy enough but is also easy to cut and shape with something like an Exacto knife?

[copperheadroads]

Forbon works for me , there must be something that easier to work with

[David King]

I've tried other materials but forbon is pretty much the easiest for it's stiffness. I use a thin kerf bandsaw blade to cut it and that's a fast and clean and accurate way to go, much better and safer than a table saw in my opinion.

[copperheadroads]

I use a bandsaw for cutting it & that works great , I dislike the way it sands ,when doing the round ends it kind of mushrooms ,I'm thinking about making a few templates & use the router

[verhoevenc]

I'm glad someone brought this up cuase I was thinking about using some wood flatwork (something high figured and flashy) but then saw a comment in another thread about a strat pickup having somewhere around 990lbs of pressure with all the windings on it. I'm thinking that the wood idea may not work as well as I was thinking it might? Anyone tried it?
Chris

[Joe Gwinn]

The 990 pounds (or so) is correct, if and only if the bobbin is more rigid than copper wire. But Forbon and wood are far less stiff than copper wire, so what happens in practice is that the bobbin crushes slightly (invisible to the eye), relieving the pressure.

[SonnyW]

I'm glad someone brought this up cuase I was thinking about using some wood flatwork (something high figured and flashy) but then saw a comment in another thread about a strat pickup having somewhere around 990lbs of pressure with all the windings on it. I'm thinking that the wood idea may not work as well as I was thinking it might? Anyone tried it?
Chris

Hi Chris, I'm the one that posted about the 990 pounds, but I later found out my calculations were wrong because I neglected friction. That made the model I was using to calculate with come out way too high. It isn't like a block and tackle after all. There is still a lot of pressure on the magnets, I've observed that pressure, but it isn't as much as I thought when I posted my calculation. I put a retraction on the original thread. I've seen some nice bobbins made from figured wood. I made a set once with model aircraft plywood, but I ended up not using them because I couldn't get the fit right on the magnet holes.

[David King]

Wood along the grain probably has a much higher compressive strength than forbon anyway so nothing to worry about there. I've used wenge and rosewood. clearly Basswood should be the next species to try...

[David Schwab]

I used wood for flatwork for a while, but had issues with it splitting at the ends. But that's because I had a slot for a blade. It was laser cut hickory.