Replies

1. 
   RickL | Jul 10, 2006 09:56pm | #1

   Brass as you know is very soft so harder bits isn't going to help.  Broken screw extractors are available from most woodworking supply stores an some hardware stores. The most popular design is simply a small metal tube with teeth cut into the end. The extractor is inserted into the drill and a "core sample" is taken from the wood around the screw. A wood dowel is glued into place and a new screw can then be fastened into the repair. Another option is to dig around the screw until you can grab the end with a pair of needle nosed vice grips or pliers. The remaining scar can be drilled out and a matching plug can be used to repair the defect. Use a plug cutter to cut a matching plug from a piece of scrapwood to match the grain of the wood.

   You can make your own screw extractor by taking a spring pin and grinding some teeth on the end. I usually grind the teeth so it works in the left hand direction as it will often unscrew the screw when it reaches a certain depth.

   http://www.highlandwoodworking.com/browseproducts/Set-3-Hollow-Screw-Extractors.html

1. 
   Roger | Jul 10, 2006 11:59pm | #3

   Thanks to you both.

2. 
   JohnWW | Jul 11, 2006 12:08am | #4

   RICKL,

   Great minds obviously think alike, and even use the same type size.

   John

2. 
   JohnWW | Jul 10, 2006 10:27pm | #2

   Roger,

   The screws can't be drilled out with a conventional drill, steel or carbide, the drill will always veer to the side into the softer wood. 

   You can drill several small holes around the shank of the broken screw to remove the wood around the threads and then use a needle nose pliers or needle nose small Vise Grips tool ground to a small point to grab the screw and back it out. 

   A more elegant solution is to drill the screw out with a tubular drill, which is just a miniature hole saw, that will drill out the wood around the screw.  I think someone makes these screw removers but you can take a roll pin with an inside diameter to clear the screw's shank and file a few teeth in one end to make a drill. File the teeth so the drill cuts in the direction that will back out the screw when the drill removes most of the wood surrounding it.

   John White, Shop Manager, Fine Woodworking Magazine

   
   

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   Edited 7/10/2006 5:06 pm ET by JohnWW

3. 
   Spalted | Jul 11, 2006 03:33am | #5

   I made one of these "mini hole saws" to do just this activity on our last library job (I switched from parafin to beeswax to aid the screw in...except on the first one...) I found that a 1/4 inch ID soft copper pipe was soft enough to file teeth into and to get some grab in the drill chuck but hard enough and just the right size to drill out the screw and leave a 3/8 inch hole that fits my plug cutter perfectly! I picked the 24" of copper up at lowes for about 1$ i think but i had to dig for a piece that was not bent from grabby hands.

1. 
   EdHarrow | Jul 11, 2006 04:38am | #6

   My experience, limited tho it might be - I used a roll pin of the correct ID (or as near as I could guess, and just filed a triangular notch at the end of the 'seam'.  I did only the one, and made no attempt to make it a 'directional' shape. 

   I chucked it in the drill, switched the drill to reverse, and had at the screw (very small but I can't remember the size) and it came out quite neatly.  I filled the hole with a mix of wood flour and epoxy, re-drilled it, and the screw is holding to this day.

4. 
   Jfrostjr | Jul 11, 2006 04:06pm | #7

   Before messing with "wood removal" to get at the screw I would try an EasyOut, common in metal working. It requires a relatively small hole in the screw.

   The tool itself is tapered, with reverse spiral threads. When inserted in the pilot hole the EasyOut is turned with a wrench (crescent wench or open end wrench) to back the screw out. Only if this process fails would I start butchering wood.

   Jerry

1. 
   EdHarrow | Jul 11, 2006 08:14pm | #8

   Depending upon the size of the screw - but I suspect they are considerably smaller than something like a #8, and I don't think one could get a sufficiently small Easy-out.

   Careful work with a center punch, and a LEFT-HANDED drill bit (McMaster-Carr) might work.

5. 
   mufti | Jul 11, 2006 08:32pm | #9

                I have removed broken brass screws by centre potting, drilling down with a fine bit and then step drilling with slightly larger bits to take all strength from the remains. An electrical screwdriver or Robertson driver then took out the debris. It took time but saved repairs and I do not work for a living (if you call this living). Good luck.