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Storm Damage Page 2

This page was last updated on 31 May 2002

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Rebuilding the Anchor Platform          Repairs to the Foredeck

Rebuilding the Anchor Platform

I decided to more or less recreate the old platform, size-wise, since I could find no inherent flaw in the basic design or the way the anchors overhung the bow.  As I looked around at boat after boat throughout my anchorage and in the boatyards, the way my anchors had been installed was no different than any other boat--in fact, many seem to be more susceptible to the type of occurrence that led to the demise of my original platform.  It would seem that the apparent hooking of the mooring line over the fluke of the CQR anchor was--ahem--a fluke.  (Pun intended.)

Since I lost one of the original anchor rollers, I ordered a new one for deliver in a few days, after making sure that it was still the best choice for the CQR.  It's a Windline Marine URM-1.

I did decide to make the new platform stronger, as I'd always harbored worries over the ultimate strength of the old one.  I debated several courses of action, including staying with a glued-up platform built entirely of mahogany, much like the original.  Whatever plan of attack I followed, though, I knew that the top surface of the platform would be varnished mahogany to match the rest of the boat and to replicate what was there before.  So, with that in mind, I figured I could at least get started...and let the rest of the plan fall into place as I went, as it is wont to do.  I can only theorize and plan so much before I have to get my hands dirty and solve the problems on the go.  
 

I began building the new platform with a length of rough mahogany that I had on hand.  The edges are straight, if rough, so I used the straightest one against my tablesaw fence to mill a nice straight edge on the opposite side; then, end-for-ending the board, I milled the other side straight and parallel.  This technique may not be perfect, but it beats messing around with the silly jointer.  The board I had, unlike my old stock (left over from cockpit coamings) was something around 8" in width, so I will have to glue up a blank in order to create the desired 12" width of the new platform.  With the long board's edges smoothed and straightened, I cut two pieces to 41" in length, more or less the same as the old platform; this length is slightly overlong to allow for a fudge factor.  I have to decide whether I will install trim over the end grain, as I did before, or if I will just leave the end grain exposed--the direction I am leaning at this point.  One reason for skewing my thinking in this direction was that, despite being glued with epoxy and screwed, the inevitable wood shrinkage had managed to leave some unevenness around the trim detail on the end of the old platform, and I think for the long haul it might be better to avoid this structurally-unnecessary joint.

Anyway, once I had the two pieces cut to length, I set up my pipe clamps and mixed a small batch of thickened epoxy--a fairly loose mixture, but thick enough not to run too easily.  I spread some on one edge of each board, after determining which two edges were the best matched, and clamped the pieces together.  I left the faces of the boards rough for now, as I'll have to do some sanding at the seam anyway to even things out, and it'll be easier to just clean up the roughness later.  I've found that a belt sander makes easy work smoothing this soft mahogany in the absence of a real tool like a thickness planer.  I cleaned up some of the excess epoxy and set the blank aside for the epoxy to cure. The blank is about 15" wide and 41" long in the rough; I'll trim it down later; the board is about a true inch in thickness.

The old anchor platform was made from two layers of 3/4" mahogany, for a total thickness of 1-1/2".  I had enough wood to do a second layer to create a thicker platform--I could glue up another two boards into a similar blank, then, later, laminate the two blanks together to form a thicker, laminated platform--but I decided to forgo that idea and create something better, and stronger.  Stainless steel was an obvious choice.  Where would I go to obtain a piece of stainless steel like this, though?  I could probably find a local metal supplier...but I don't really have the time, nor the inclination, to chase down supplies at this point.  Frankly, this is an unwelcome project at this time.

I turned to my old friend, McMaster-Carr.  Of course they'd have something that would work out.  They have everything, and their service is so spectacular that, if I ordered now, I'd have the product the next day.  By ground shipping...no rush charges necessary with these guys for overnight service.  Searching their website, I was initially intrigued by the prospect of aluminum instead of stainless steel.  Lighter, strong, easy to machine...it seemed an interesting choice.  However, I was stunned by the price of the size and thickness I needed...after making the mistake of misreading the website and thinking how reasonable a large piece of 0.050" aluminum plate was ($27 or something).  Yes, I know...that's an extra "0" in there, so it's not 1/2" aluminum, like I thought.  1/2" plate, once I found the real stuff,  was staggeringly expensive.  Forget aluminum. 

I did have a little fun contemplating something exotic like a carbon fiber panel, or even an all-aluminum honeycomb panel product.  But I decided that these were too expensive, too unproven, and, in the case of the aluminum honeycomb, not really strong enough for what I was attempting (based on their supplied deflection numbers and weight ratings).  But it was fun to play with the idea, and to file away the thought of another interesting product.

I ended up ordering a piece of 3/8" 316L stainless steel plate, 12" wide by 24" long.  This will be about perfect--it's over half the length of the platform, the exact width, and will support the oh-so important forward part of the platform, the overhanging part.  The stainless will go on the bottom and is strong enough to do all the work itself, with the mahogany secured on top mainly for looks.  Having the stainless beneath will make an automatic, built-in backing plate for the bolts securing the anchor rollers, adding even more strength to their installation.  And the overall thickness of the platform will end up just a bit thinner than before, which will give a little more clearance around the roller furling drum and a fairer lead for the mooring lines.

The only possible stumbling point for my plan will be cutting out the stainless steel to go around the stem casting and headstay...that will not be fun.  Whether I can do it myself or not remains to be seen.  Stay tuned for that!
 

I decided to salvage the solid mahogany after supports from the old platform.  These are necessary to make up the space between the deck and the platform caused by the raised flat area on the stem, where the toerails meet.  Carefully setting the fence on my tablesaw, I cut these blocks, which were intact and in good condition, off the bottom of the old platform, cutting so that the full 1-1/2" thickness remained.  Then I set the fence again and trimmed off the junk from the bottoms of the supports--5200 and, in one area, some fiberglass from my deck.    I'll reuse these supports on the new platform, pretty much as is.  They have the added benefit of having the proper bolt hole locations already set, so I can reuse the plywood backer plates that are still attached beneath the foredeck.  One less thing to have to redo.

oldplatformcut.JPG (169580 bytes)brokenplatformend.JPG (148856 bytes)The old platform, despite missing a piece from the forward end on one side and being cut in half, will be retained throughout the duration of the new platform construction for reference and to ensure that everything ends up in the same place--bolt holes, the cutout for the headstay, what have you.  Then it will be sent to the scrap heap, where it will eventually find a new life integrated into some other project.  There's still plenty of good wood there...it was too bad to have to saw it down the middle in order to remove it, but I'll sacrifice wood any day when the whole deck is in jeopardy.  That was enough for the day--it was late.

The next day, when I got home from work at about 1:30 in the afternoon, my box from McMaster-Carr was waiting for me.  I just love that place...(maybe I'll marry it).  Fewer than 24 hours from the time of my order to delivery.  Wow!
 

The 3/8" stainless plate is a massive affair.  It is fairly heavy...I hope I don't sink my boat bow-first!  One thing is for certain, though:  it will not break.  (Or, if it does...well, I don't want to imagine the scenario that could do it.)  It is 12" wide  by 24" long, the best compromise of the sizes offered.  The plate is long enough to support the overhang, rest on the stem, and extends back far enough so that the first of the three sets of boltholes securing the platform to the deck passes through the plate.  The rest is gravy.  I realize this is overkill, but overkill never hurts in the long run when you're talking ground tackle anyway.

platformblank.JPG (167148 bytes)blanksanded.JPG (175208 bytes)When the glued up panel cured, I removed the clamps and, after sanding off the excess epoxy, trimmed the panel down to 12" in width, the finished dimension.   The length as glued is the proper 41".   Then, I spent some time sanding the rough surface of the panel smooth, first with a belt sander, then my random orbital.   The photo on the left is the panel before; on the right, the panel after sanding.
 

When the panel was sanded to 80 grit, I used my jigsaw to cut out the center portion in order to accommodate the stem piece and headstay on the boat.  I used the old platform as a guide, and made the cutout slightly bigger than before.  Then, I rounded the top edges of the cutout and the platform with a 1/4" roundover bit in my router.  Placing the platform over the stainless plate, I marked that for the stem cutout.
 

dadosinfeet.JPG (147677 bytes)Because the plate will extent back into the section where the "feet" are installed at the aft end of the platform, I had to remove a section of the top of the forward part of the feet to allow the plate to slip in.  I used a dado head cutter in my table saw to remove a little over 3/8"  of thickness on each of the feet salvaged from my old platform.  Then, I secured the feet to the platform with epoxy, clamping them in place overnight.  (20/20 hindsight note:  wrong!  This was a mistake.  Minor problem...but I should have added 3/8" instead of subtracted.  See below for details.)

To continue the construction of the anchor platform, please click here to go to the next page.

 


Glissando, Pearson  Triton #381
www.triton381.com 

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