Fly Cutter....

[danielhv]

I must be doing something wrong... cause I got this one from Sears:

http://www.sears.com/shc/s/p_10153_12605_00925293000P

and it isn't working for ****! Very sloppy holes, keeps moving the cutter to a different angle no matter how tight I tighten the set screw, etc. I butchered one of my tie down spacers cause the blade moved on me and started cutting the hole too big! Also, there is no easy way to make an exact measurement of where you have it set, there are no directions that come with it (although it should be self explanatory, but I must be doing something wrong because I have seen other builders that have used the same exact one!). Is there a better one somewhere or a better way of cutting holes?? I bought a 1" hole saw, but I'm sure I'll need to cut different size holes at some point in the build, I only hope there is a better way to do it!

[LifeofReiley]

I found speed to be one of the main issues when using a fly clutter. I think the one I have came from Avery Tools, its probably 13 years old now. The other thing I've done is to always put the piece I'm cutting on a larger flat piece of wood. Clamping everything down also helps but can be time consuming.

YMMV

[bullojm1]

Daniel-

I have the same fly cutter and it works wonderful for me. First dumb question is are you using it in a drill press? Are you clamping the material you want to make the hole in down? Finally, make the drill press spin at the slowest speed possible - 300 RPM or so.

The final hole the fly cutter makes isn't the cleanest thing in the world. The fastest way to clean up and debur the hole is to use a dremel with some sanding drums.

Finally, as a safety tip with the fly cutter - don't use shop gloves with it. If your glove gets caught in the fly cutter it will take you hand with it since it is moving at a slow speed / high torque.

[danielhv]

Originally Posted by bullojm1

Daniel-

I have the same fly cutter and it works wonderful for me. First dumb question is are you using it in a drill press? Are you clamping the material you want to make the hole in down? Finally, make the drill press spin at the slowest speed possible - 300 RPM or so.

The final hole the fly cutter makes isn't the cleanest thing in the world. The fastest way to clean up and debur the hole is to use a dremel with some sanding drums.

Finally, as a safety tip with the fly cutter - don't use shop gloves with it. If your glove gets caught in the fly cutter it will take you hand with it since it is moving at a slow speed / high torque.

Yes, its on a drill press, at the lowes RPM the press will run (650rpm). Im clamping it to a piece of 2x4 thats about a foot long.

[hydroguy2]

Below is a pic of mine. not sure where or when I picked it up. But once locked down it doesn't move.



Like everyone said:
1. drill press only
2. slowest speed possible
3. clamped tight
4. easy on the pressure

also make sure your bit is in correctly. The one in your Sears photo won't work properly for ID holes. My holes needed very little work after drilling and the diameter was spot-on.

[TJoyner]

I had big time problems as well until I realized I had the blade oriented the wrong way, then it worked like a charm...

[hydroguy2]

Originally Posted by danielhv

......at the lowes RPM the press will run (650rpm). .....

that's way too fast. You'll be lucky to make that speed work.

[danielhv]

Originally Posted by hydroguy2

that's way too fast. You'll be lucky to make that speed work.

ok, so is there an alternative besides buying a new drill press??

Here is the one I'm using:

[hydroguy2]

if you've got it going as slow as possible at 650rpm, your best bet is to make nice with the local machine shop. Have him cut the few big holes you need.

I'm not certain what you are trying to cut (got the QB -7 myself). but for thinner stuff you can use a punch, like these knockout punches.

[captainron]

As others have said, it's all about speed. 250-300 RPM max! I had a bench drill press like that, but had to get a floor model to get the speed and stability needed for using a fly cutter. Maybe check the local paper or Craigslist for an inexpensive used one. Also, Greenlee chassis punches work well, but are expensive. Harbor Freight has much cheaper ones which are probably fine for the limited amount of use on aluminum that this project needs.