# Celtic knot inesrt stock drilling tip.



## jfoh (Jan 21, 2010)

Posted this on another thread but it may be missed. So sorry if you see it twice. Wish I had seen one like it earlier. It would have saved me a lot of headaches with these knot blanks. It is a way to get the stock inserts, in the blank, with almost no problems with blow outs when drilling. I pre drill the insert before I glue it in the blank. Here is what I do with brass stock. It has eliminated 99% of my blowout problems.  It will work with any type of inserts the example is just brass because the other thread was about brass.   

Did you ever think about making a jig to hold your brass and pre-drill it before you insert it in the blank? Also drill the brass with your bit before you put it in the jig. This makes the hole fairly close to the final size. The jig then holds the brass stock and lets you turn a round hole into an elongated hole.  This elongated hole is what the final blank needs.   

I took a hard maple blank. Drilled it with the same size bit the real pen blank will need. Then cut it like it was the final blank with the cut being at the exact angle the celtic knot will be cut. Drill the brass stock with the proper bit flat-wise and you have that round hole. Then set the brass in the saw slot. Center the brass stock in the jig making sure the hole is in the center. Place  one drop of CA to hold the brass in the slot if loose. Drill the blank again this time drilling the brass at the correct angle. When your take the brass back out you will have a elongated hole as the drill bit goes through the brass at the correct angle.  I cheated the other day and made my jig with three slots. I could create three brass stock inserts at a time with an elongated hole that was perfect for the celtic knot. Do just one at a time as you start out. 

Make sure you glue the stock in the final blank with the elongated hole in the right direction. I mark the top of the stock with a marker so I make sure I get the elongated hole in the right direction. I never cut all the way through the blank. Just 7/8's the way through. The slot holds the brass stock but the blank must be exactly square or the knot gets lopsided. 

Now I have two ways to drill a celtic knot blank. Like most I have cut and glued repeatedly and then try to drill the entire blank. Hard to hold your breath that long as slowly and carefully you drill a blank that you have spent ten hours working on. One slip, one misstep and you have scraps. 

You can pre-drill your brass stock as detailed above and most of the stress areas in the center of the blank will not have a solid brass mass that has to be drilled out. It will be a almost perfectly centered brass stock with a hole already where you need it. You need to drill it as normal but most of the danger areas are already drilled out as the brass stock is all got one hole in each. If you centered it properly your drilling is almost never a problem. Almost.

Now when I get real concerned I drill the final blank end to end before I start. The blank must be exactly square. Then as I cut and glue the brass stock I put a cork shim down the hole in the blank. It centers and holds the brass stock while the glue cures. It is easy to drill the cork stopper right back out and leaves no mess in the blank. Turn, cut, glue, remove the cork, chase with a drill bit  and repeat until done. Then just chase the blank hole one more time and you are ready to glue in the brass tubes.  

I know it is a lot of steps but it is simple if you just think outside of the box.


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## snyiper (Jan 22, 2010)

Those are some great Ideas, you may have saved me from inventing some new words!!!


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