fixing keel plate

[jerome]

İ will need to fix the keel plate soon and İ have decided to do what Ben did, wich is pretty much the İkea method. İ think Josh did the same.
That is:
-drill 2 longitundinal, 20 cms (+-8inches) long holes. First hole at about 20% aft leading edge, second at about 35% forward of trailing edge. İnsert long stainles steel bolts
-those holes will be overdrilled, filled with epoxi silica, then redrilled to proper size
- drill 2 perpendicular holes through the side of the keel in order to fit nuts and washers on the ss rods.
-bolt the plate tight
-fill perpendicular holes (side holes with nuts and washers) with epoxy putty.

My only concern is about drilling the long 8 inches long holes. The only tool İ have is a hand drill. Any suggestion for an easy jig to make sure holes are nicely drilled ? İ would hate to mess that up and see my drill bit surfacing through the sides...!

[jerome]

İ found Chad's jig....İ knew İ had seen it somewhere !
http://2.bp.blogspot.com/_5HeG270aMbM/S ... GP1663.JPG

Chad, how stable that was ? This is actually more a guide than an actual jig, right ? İ mean the tool is not held into position. There is just a hole to guide the driller's bit but it wont avoid the bit from wobbling if you are not firmly holding the drill. İ guess you just need to concentrate on aiming right on target and maintaining the drill bit in the center of the jig hole.

Has anyone else tried another solution ?

[Chad]

Using that jig:
Buy an extra long drill bit- something over a foot long. Doesn't need to be your finished hole diameter, but at least 1/4" / 6mm or so, preferably 3/8" / 9mm.
Use the jig tight to the end of the foil to start your holes in the end of the foil. Use the long bit for the holes in the template, and these starter holes. 1/2" deep is plenty.
Move the jig further out and clamp it as shown in the pic you found above, checking with straight edges that it aligns nicely.
Using your long drill bit, drill through the template's guide holes, into the starter holes in the end of the foil, and as deep as you need to go. Use your drill's full RPM, drill slowly, and pull out frequently to clear the chips from the drill- all steps to minimize any tendency of the drill bit to wander as it encounters grain features in the wood.
Remove the jig, re-insert the drill bit into each hole, and use a straight edge to extend the visible portion of the drill bit and draw a line on the foil representing the center of the holes. Now you know where to drill the cross-holes to accurately intercept the bolt holes.
Drill the bolt holes at least 1/16" / 2mm bigger than your bolt diameters. I would NOT recommend filling these holes with epoxy with the idea of re-drilling them to size- no drill bit/jig will do that accurately enough. Much better to cast the bolts in the epoxy. Use a sharp drill to cut these holes, and cut them quickly with as little hole burnishing as possible- you want the hole sides to be rough and not polished at all before placing the epoxy.

Also, do not cut square corners at your cross-holes, no matter how tempting it is to give your washers a flat seat to bear against. Better to build up a seat of epoxy inside the hole than to create such a stress-riser. Make the cross-holes as small as you can. At 8" of hole depth, they can easily be omitted if you cast the bolt in epoxy over this length, but I understand that it gives folks an intuitive sense of security to know there is a mechanical connection holding the keel on, rather than "just glue". Which is fine...

[M&S]

I will agree with everything Chad has posted here. Especially the bit about not trusting the 8" long overbored holes with thickened Epoxy slurry holding the keel bolts in place. But it works

[bendoo]

as far as drilling the holes straight, I just eye-balled it.
lay the keel down horizontally onthe bench or the ground, but w/ the trailing edge or leading edge pointed straight up in the air.
hang a light directly above the centerline of the foil and just off the end.
place the drill bit tip on the centerline and make sure the shadow runs straight down the center of the top of the keel.
get your eyeball over the bit...as long as you can't see the shadow, and that shadow continues to remain on the centerline, you are drilling straight into the foil. also keep an eye on your horizontal orientation.
easy-sleazy baby!
bd

[Shazza 273]

What, none of you like my full length 12mm galvanised threaded rod to bolt the top plate to the bulb ?

[jerome]

Chad,
great technical advices. Really helps to understand how to efficiently use the jig. And also thanks for the details of avoiding the squared angles or re-drilling into hardened epoxi

Ben, loved your technique ! But one needs balls to drill those holes without any guide ! İ dont think İ have that much confidence in my drilling abilities.

Josh, my forever supporter and motivator ! My keel and bulb were already built before you disclosed your method of threaded rod from top to bottom. İf İ had to do it all over again, i would do it like you. İt is certainly the strongest method. No way the bulb nor the plate can fail.

Just as a last note, İ have hanged my keel from the ceiling to fair and finish it. And that baby is heavy because my keel is made of oak, probably close to 205lbs (yes İ know it is out of class limits). İn order to hang it, İ just screwed an inox handle İ had leftover on the top face of the keel with two 8cms wood screw. Normal usual wood scres. İ lifted very carefully and those little screws did a great job of holding those 200 lbs !
So i can indeed imagine that two, 8 inches long , 9mm diameter, stainless steel bolts embebbed in a resin silica putty will hold the top plate in place no matter what ! Maybe İ will forget about the counter holes afterall.....

Thanks guys.

[jerome]

Has anyone used QZ 5111 from Huntsman as a release agent ? http://www.johnburn.co.uk/docs/COSHH/QZ%205111.pdf. That is the only thing İ found in Turkey. İt seems to be some kind of wax in a solvent solution.
İ intend to use it on all my bolts holding the keel plate, the compression post and the mast foot.

[Chad]

That looks fine. Other stuff that works is cooking spray (like "Pam"), or teflon dry-lubes such as "McLube" or any of the generic versions from car parts stores and such.

[jerome]

Just wanted to inform you guys that although İ still did not fix my keel plate, İ used the release agent and the burried nut technique on my compression post base reinforcement and it worked like a miracle.
İ drilled oversized hole on the piece of hard wood İ had installed, filled it with fresh epoxy/silica, dig the bolt and nut inside and let it dried (Of course the bolt had been previously covered with the nice waxy release agent İ got). Then i just unscrew the bolt using a bit of elbow grease for the first spin.
As a result i had very tight, nice, threaded hole with a strong nut inserted deep inside. Placed the compression post and just bolted it down.İt looks really solid.

İ also pretty much did the same with the mast foot base and İ am happy. With a bit of Silika sealant, no water should come through whatsoever.

[Kevin]

I had a similar experience when I fixed my keel plate. Nice big hole, left it rough, worked in the epoxy which was not too thick. It's rock solid.

Keep up the good work. Kevin.

[jerome]

Thanks Kevin,

İ did fix my keel plate during the weekend and İ used all the best practices described by all of you. İ was a bit scared of the drilling part but it went great and İ will update my blog with some pictures on how İ did it. İ practiced a lot on left over wood İ had , was too lazy to build a jig like Chad and went for something like the "Shadow technique" used by Ben..... The holes came out perfect.
Then İ inserted two 12mm rods, 20 cm deep , into epoxy/silica filled 16mm holes, and it does seem really solid indeed !
You also mentionned something very important in your last post about the expoxy not being too thick. İf it is too thick, it will not fill the whole length of the hole properly.