Voids (?) found adjacent to handrail bolt holes

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Michael

Well, the first part of the project is complete.

Lionel (another co-owner) and I discussed at length the merits of drilling out the bolt holes but demurred.  Phil's suggestion on how to get the bolts reinstalled at the correct angle seemed less likely to work if we drilled the holes larger.  We feared that if we drilled out the bolt holes and filled them entirely with epoxy there would be considerable opportunity for us to reinsert the bolts askew so they didn't pick up the handrail correctly. Thinking about it now, I think we could have measured the bolt angles with a protractor and pencilled radial marks every 90 degrees around the holes to indicate centres for drilling out new holes...but that is an after thought.  There's probably some even simpler trick along the lines of the one Phil suggested but it wasn't obvious to us.

In any event, as there was no evidence of rotting of the plywood, we settled for cleaning the bolt holes with a dremel sanding wheel and then paying (to a very limited extent) the voids adjacent to the bolt holes with a fairly thick epoxy resin (West Marine resin, hardener, and 404 filler I think).  Our intention was not to fill the voids but only to seal the bolt holes off from the voids so that any water that did get into the bolt holes would not run into the voids.

As for the plywood deck core adjacent to the holes, since it seemed completely unrotten Catalina might be vindicated in its decision not to have "lined" handrail bolt holes, at least on Hali. We probably smeared a bit of epoxy resin onto the plywood core while paying the voids lower down in the holes but we really didn't make a conscious decision (although we probably should have) to "paint" the plywood core next to the bolt holes with epoxy.  Hopefully, the next 10 years will see no more rot develop there than in the first 10 years of this boat's life.

We did the epoxy work from the top of the holes.  Although the "voids" were nearer the bottom of the holes than the top, we found it was impossible to pay the voids from below without drooling epoxy into the cabin.  So we sealed the bottom of the holes with duct tape and filled from the top.  Likely, we will have to drill out the holes a bit.  None of this could be easily photographed or would be too interesting to see in photographs, so no pics.

On further thinking about the repair, I think we should have measured the bolt angles and marked the bolt centres (as mentioned above or in some other fashion) and then drilled out the holes two sizes bigger then filled the holes entirely and finished up by drilling the holes to size. Perhaps we can test that technique on the port handrail, with the stb handrail providing a control.

Unless something unusual materializes in the re-bolting process, I should think this will end my posting on this subject.  Many thanks to all of you who tried to set me straight.



Michael MacLeod, "Hali" 1997 Hull #1352, Universal M-35B engine, Vancouver, BC

Stu Jackson

Glad that worked for you.  I was thinking of you and how to line up the holes, seems that a little chalk line(s) would work on the surface to get the hole centerlines where you need them.  Just also came across this on another board:  http://www.boatus.com/boattech/casey/39.htm  Maybe helpful to others and for your "other side".
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  Cowichan Bay, BC  Maple Bay Marina  SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

Michael

Stu, thank you for your follow up and the Don Casey article.

Your post and his article have caused me to second guess the wisdom of shirking the full drill-fill-and-drill routine with these handrail bolt holes.  I will probably go back and do the full job.  (My father used to say, If you don't have time to do it right the first time when will you have time to do it again?)

At first, I puzzled about your reference only to making centering marks and not to measuring the angle of the bolt as it emerges from the deck.  In other words, it seemed to me at first that you thought it was sufficient to make marks on the deck only to indicate the centre of the top of the hole and not necessary to determine the angle the bolt makes to the deck (eg. in the rather convoluted way I had suggested in an earlier post in this thread, by using a protractor).  However, it does work (and probably this is what you meant) if we make centering marks at both the top of the hole (on the deck) and at the bottom of the hole (on the headliner) before filling with epoxy.  Then, when we drill (probably a pilot hole to start with) from top dead centre to bottom dead centre (based on the marks), or vice versa of course, through the new epoxy filling it is inevitable that we will be reproducing the angle and location of the current hole: the machine screws will fit the female threads of the handrail perfectly.

So it shall be tried.

Regards and thanks again.


Michael MacLeod, "Hali" 1997 Hull #1352, Universal M-35B engine, Vancouver, BC

Michael

Subject to correction by the more knowledgeable on this site who helped with advice along the way, here is how to re-bed a stainless steel handrail on a Mk II Catalina 34 and deal with voids that may be found adjacent to the handrail bolt holes.  This summary is based on experience with the starboard, trunk cabin roof mounted, five-bolt, stainless steel handrail on a 1997 C34.

The decision to re-bed the starboard handrail was made after water was discovered leaking into the galley from the head of one of the five machine screws ("bolts").  The bolt head was rusty.

1.   Remove all cushions and valuables from the galley-salon.  Tape newspapers over everything out for a few feet from the windows.  Something is sure to fall/drip: in my case, fiberglass dust, sawdust, and epoxy resin.  I found removing invisibly even a few drips of hardened epoxy resin from the cushions to be impossible...so it was cut-out and sew.

2.   Unscrew the bolts retaining the handrail.  You will need a Phillips head screw driver.  The bolt heads are located between the curtains and the windows in the salon and galley.

3.   Remove the handrail and place it inside the boat, lest it sink.

4.   Using a pencil or other eraseable marker, mark on the deck the top dead center of each of the bolt holes by drawing at each hole a cross with one axis running fore and aft and one axis running transversely.  The transverse axis is the more important: the handrail will not stretch or shrink longitudinally so when you come to re-drill the hole you want to do so as accurately as possible in a fore and aft direction, that is, on the transverse axis; but there is some lateral flexibility in the stainless steel handrail (at least at either end), so you may have a bit of leeway (at least on holes 1 and 5) in that direction, so the accuracy of your drawing of the fore and aft line is not quite as critical.  Make sure you extend the radial lines far enough -- say three inches on each side of the hole -- so that they will not be drilled out or disappear under the tape or be ground off in the steps to come.

5.   From on top, drill out each hole 2 sizes larger. The hole you drill should be somewhat smaller than the diameter of the base of the handrail so that the epoxy plug you will fashion below will not show when the handrail is re-installed.

6.   Check the sides of the holes you have drilled.  I assume you are finding voids off the sides but the plywood deck core you find is not soaked.  (Stu Jackson advises if you are finding soaked plywood, then you'll need to ream out the holes as far as you can.)

7.   Sandpaper the sides of the new holes (to give the epoxy resin with which you will fill the holes in a later step some roughness to adhere to).

8.   Wipe the holes clean with an appropriate cleaner – I don't know which one to use, perhaps Interlux 202?? – to get rid of the fiberglass and plywood core dust from drilling and sanding.   I missed this step.

9.   From below, tape over the bottom of each hole.  Duct tape works fine.

10.   Tape with masking tape all around the top of the hole to protect the deck from the coming messiness.

11.   Make a batch of epoxy resin and filler to peanut butter consistency.  I used West System epoxy resin and hardener and one of their fillers, 404 I think.  If this "goop" is too liquid, voids adjacent to the hole will drink more of it than necessary.

12.   Pour/spread the goop into each hole, pressing it some way – an inch or two will suffice, I think - into any voids adjacent to the hole.  Your goal in packing the goop somewhat into any adjacent voids is not to fill the voids but just to create an epoxy-filled area immediately adjacent to the hole so that no water can get into the voids from the bolt holes that you will re-drill.  Complete filling the hole until the goop sits somewhat proud of the deck. The goop will likely ooze a bit over your deck-protecting masking tape. That's okay.  The goop may also settle a bit as it oozes further into the voids.  As you don't want to have to repeat the process later, it is better to err on the side of leaving too much of a mound of goop proud than too little.

13.   A day or two later, grind the epoxy plug flush with the deck – a Dremel tool with a sanding wheel seems to work well - and remove the masking tape.

14.   From on top, with a small diameter bit, drill a pilot hole vertically -- using a drill with a bubble level helps with this - through the center of the old (now hardened epoxy-filled) hole. (It seems, at least on my boat, that Catalina drilled the original bolt holes vertically, so while I needed to center the drill bit accurately there was no need to worry about drilling the new hole anything other than straight down.)

15.   Re-drill each hole with a drill bit one size larger than the handrail bolts.

16.   Fill the top of each bolt hole with flexible bedding compound. I used Sikkaflex 291 but opinions about the merits of bedding compounds will vary on this site.  Following the advice of Don Casey in an article cited by Stu Jackson at this thread, don't put any bedding compound near the bottom of the bolt hole: if water leaks around the handrail bolt, you want it to flow down into the cabin, where you will see it as a sign that it is time again to re-bed the handrail.  You don't want the water to pool invisibly and remain where it can do damage to your deck - that is, above a plug of misplaced bedding compound at the base of the bolt hole.

17.   Insert the handrail bolts from below.  Add bedding compound as needed around the bolt/handrail junction. Tighten the handrail bolts completely into the handrail.  (This is not a case where there is a nut that can be left somewhat untightened until after the bedding compound sets.  In this case, if you leave the handrail bolts untightened and tighten them later, you will break the bedding compound seal.)

18.   Wipe off any excess bedding compound.

19.   Erase radial lines.

Thanks for the help of all posters who contributed along the way.  Corrections/improvements would be welcome.


Michael MacLeod, "Hali" 1997 Hull #1352, Universal M-35B engine, Vancouver, BC