Help with hole on top of mast

I'm building a Skerry with a balanced lug rig. The directions call for a one-inch hole at the top of the mast, rounded over to help keep the line that goes through it from binding. What type of bit do you recommend for drilling the hole, and what kind of tool for rounding it over? I bought a 1/2" roundover bit for the mast itself, but I'm worried about split-out at the top of the mast. The hole is only supposed to be one inch from the top.  Thanks!


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RE: Help with hole on top of mast

Hi, Potbelly Slim,

I suppose there are reasons NOT to do what I did but I had the same worries about drilling a big hole in the top of the mast--especially since I had planed the mast down to about an inch square at the upper end in the first place. So I drilled a 3/8" hole, fed a 1/4" line through that, and lashed a small block up there. I run the halyard through the block and I really like how easily the sail is raised/lowered. No issues with twisting or anything as the block is lashed tight to the mast. Just a thought. 

Barbara

RE: Help with hole on top of mast

   Thanks, Barbara. Does your solution allow the yard to be pulled all the way up?

RE: Help with hole on top of mast

   I went ahead and got a good wood bit and drilled the hole.  I did have some tear out because I was doing it freehand without backing material.  If I were to do it again, I'd clamp it between scrap boards and use a press if I had one.  I rounded it over with a round rasp, sandpaper and elbow grease.  I coated several times w/ epoxy and a little fumed silica to fill the ragged places in the grain and resanded it before varnishing the whole mast.  Works ok for me. 

RE: Help with hole on top of mast

   It turns out that the hardware store doesn't have regular bits larger than 3/4". So I'm guessing that leaves a Forstner bit  an auger bit. Anyone?

RE: Help with hole on top of mast

I spent a lot of time in the moaning chair about that 1" hole for the 1/4" halyard of our lug rigged PMD.  I was mighty reluctant to deviate from the directions, but it looked like a mighty big hole and not a lot of room for error.  In the end, I figured I could always make a hole bigger, so I drilled a 1/2" hole, well rounded out.  With lots of sanding and working with round files, then multiple coats of epoxy, and then urethane varnish over that, the line runs through it just fine, with no tendency to bind going up or down.

.....Michael

RE: Help with hole on top of mast

   I keep belt sander belts when they wear out and rip them into various sizes, for this like a half inch or so, and after drilling the hole, run it in and out wo it rounds both sides at the same time..guarantees no split out in that narrow area.

I have a bunch of pics if you are interested in how I rigged it.  Here's one:  I turned the mast 1/4 turn and ran the lazy jack lift line thru the mast and added a cheek block for the halyard...both have very low working resistance so when I pop the halyard both fall quickly and evenly.

Curt

 

 

RE: Help with hole on top of mast

 For a hole larger than 3/4 and going to a regular hardware store, you need a spade bit.  They work well for things like this.  Avoid the new Irwins that have a screw tip, better left to construction.  The standard point works great.  Drill from one side, by hand is fine, just until the tip pokes through.  Then use that to start again from the other side.  Perfectly clean hole both sides.  They essentially scrape rather than cut and a good sharp new one leaves a nice burnished surface inside the hole.  

They come in lots of sizes over 3/4, 1" is easy to find, but you can find sets that increment by 1/16ths over 1".  DO NOT try enlarging a hole with one of these.  

Round over CAREFULLY with that router bit, or more safely by hand.  I use VERY nice hand made rasps, think pattern makers rasps from days of yore, but sandpaper will do fine.  Careful chiseling will reduce the amount of wood you have to move as well.  Chisel an even bevel the best you can, then round that over.  Should come very even done this way.  A coarse half round sharp metal file will do nicely as well.  Keep a card file handy and clean the file often (simple wire brush will suffice).  Remember, files cut on the push stroke only, it matters.

Mike

 

 

RE: Help with hole on top of mast

   Yes, Potbelly Slim, the yard does sit an inch lower than it would otherwise but I'm not too exercised about that, myself. BTW, I did what Curt mentioned--used a narrow strip from an old belt sander to smooth the interior and round over the edges of the hole (rather than a bit). My solution to hole-drilling anxiety may not be super-optimal but it worked for me. Let us know how you fare!

Barbara

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