Accessing chainplates

[Della and Dave]

So on Friday 2/7, we will be pulling the masts on Polaris, assuming the forecasted 20mph winds and snow don't materialize.  In any case, I am planning on gaining access to the chainplates to make removal quicker once the masts are out.  Anyone have any sage advice or words of wisdom to impart?  I doubt the chainplates have been removed since they were installed.  I'm expecting a lot of bad words to be said, some of them directed at Dave through text messaging. 

Also, any cautions on removing the masts, other than the obvious protect the bulkhead and don't rip the heater off?

Thanks!

Della
"Polaris"

[Dale Tanski]

Della,

Removing the mizzen can be an issue because of the Triassic stay that goes between the top of the main mast and the mizzen.  The issue here is you must remove one end, and the end at the top of the main mast is very difficult to do.  The combination of the main mast backstay and main topping lift provide little to no access to pull the pin on the Triassic. 

If you are lucky and the turnbuckle is on the main mast end you could unthread the barrel and separate it that way.  No matter what someone has to go up the spar to do that. 

We have found the best way for us is to lower (tilt) the mizzen forward toward the main mast and remove the mizzen end of the Triassic first.  We also step and lower our mizzen by ourselves off of the main mast.  The procedure is rather simple.  We remove the mainmast boom and disconnect the main backstay.  We then disconnect the lower mizzen shrouds and move cap shrouds to the lower shroud chainplates. This gives the additional length required as the mast tips forward.  You could remove them all together but it is comforting to have something to limit side to side movement.  We hook the mizzen halyard to the main halyard.  We slowly ease off the mizzen backstays while taking up on the main halyard. The mast begins to tilt forward. If you do so in controlled small amounts, the mizzen will basically rest against the back of the main. We then lift the butt end of the mizzen on to a cushion off of the base.  Disconnect the cap shrouds and lift the butt end of the mizzen off of the boat and then control the decent of the mast to the horizontal.  In our marina that is $125 saved.

As for the main mast, getting the wiring through the little hole on the backside is the biggest pain as they must be tucked into the mast before it is lifted through the deck. I wrap a blanket around the lower part of the spar to make sure it doesn't scrape the bulkhead. The blanket of course stays behind.

Good luck...

Dale

[PeteW]

If I understand your post, you are going to inspect the chain plates. Removing them is perhaps the only conclusive way to do that. But you do not need to pull the mast to work on the chain plates. I've replaced my chain plates, and made repairs to standing rigging, replaced halyards that went missing and replace the mast step with the mast in place. The only task that I can see that requires removing the mast would be if you need to work on the mast head assembly to replace sheaves. Mine were frozen but a big hammer to the pin loosened them up. The other thing is rewiring because the strain relief for the wiring harness in the mast connects to a loop on the underside of the mast head.

Don't want to see you making a job bigger than it really needs to be.

Pete

[Della and Dave]

Thanks Pete and Dale.  Della went to Seward Friday to pull masts, but snow and 40+knot winds.  Better judgment prevailed.  We will have a crane and a bucket lift that can pull the pin on the Triassic. Trying again tomorrow.  The reason to go ahead and pull the masts is that a crane is available and that she is in the yard on the hard and we have the equipment available.  We could do the chain plates one by one, but with shipping times to and from alaska if we need to get new ones made, I think it is faster to do it all in one shot.  Our insurance company insisted on new rigging.  We probably could have gotten them to accept an inspection, but they are probably original, so are past their sell by date, so didn't choose that battle.  The rigging actually looks good still.  I think we are going to follow Dale's lead and up the thickness on the mizzen chain plates to 1/4.  We also have some wiring or bulb out issues as well.  Don't know which yet. 

Anyone have a recommendation on a good LED tricolor and/or anchor light?  Do the replacement LED bulbs for the old style ones work well?  For lying at anchor, the lower current draw would be nice and I don't like the idea of having to climb the mast to replace bulbs any more often that I have to.  We also have spreader lights and one is out.  They aren't the same urgency for going LED because we won't be using them as much, but the incandescent bulbs are expensive anyway and the LED lamps are not that bad anymore.  I am thinking about "Kevin"  or Kevin Jr"  from the Dr. LED. I don't know how much light I would really need.  There are some that offer a red light LED, for night light, but I don't know how useful that would really be.  In the Winter we have dark, but aren't sailing.  In the summer, we will be sailing, but it isn't dark much. 

Eventually we want to go cruising, maybe all the way around, but that is a few year (6?) in the future.  I want to avoid too much of the "while you are there"  syndrome, but there is some logic to it.  We are going to do a some new seacocks while she is getting a new bottom job, all the way to the glass layer, and new balls and seat in the others.  All our big seacocks are made by Perko.  The ball inside is still sealing, but the chrome plating is starting to go.  While they are out, it makes sense to replace the valve seat and ball at least and that is only 45 bucks each for the kit. 

[Leo]

When I changed out the chainplates on Sol I sent one of each size to Garhauer Marine and they made new ones for a great price. I don't remember how much it was but much less than an off the shelf item. And they were exact copies. You may be money ahead to just order new ones and change them out one at a time and not pull the mast.
My chainplates were in pretty good shape but since I was changing out the standing rig it seemed like a good idea to change them out.

Len

[PeteW]

I bought my chain plate blanks cut to size from onlinemetals.com. Right down the road from you in Seattle. Here's what to buy:
Qty 4   SS T-316/16L   Annealed Rectangle  .375" X 1.5" cut to 16.5"      (uppers)
Qty 4   SS T-316/16L   Annealed rectangle   .25"  x 1.5"  cut to 12"         (lowers)
Qty 4   SS T-316/16L   Annealed Rectangle  .1875 x 1"    cut to  10.125" (mizzen)

My cost was $215.00  You will need a drill press , belt sander and a bench grinder to finish them up and a 1/2" and 3/8" cobalt drill.  You can use an old one for a pattern but somewhere on this blog is an actual drawing. Also get all new nuts and bolts and washers. I beefed the mizzen plates up to .1875" instead of .250". Seems adequate and does not require so much cutting to enlarge the slot in the deck.  I also bought off the shelf SS chain plate covers to replace the Pearson aluminum parts which vaporize over time. Check for rotten deck core when the plates are out. Excavate rot, dry and repair as needed with West System epoxy.

I did not replace my jib stay plate as it is exposed. But in hindsight I will need to at a minimum re-bed it and replace the bolts.

Pete

[Della and Dave]

Thanks for the great advice. We ended up just measuring the standing rigging in place. Much easier and less nervous-making! We will just pull chainplates one by one as we replace the wires. I like the idea of just going ahead and making new ones to install. I think Dave let me buy the boat to justify new tool purchases!


Della

[Della and Dave]

Cobalt Drill Bits!!!

Dave

[SailingSeaDragon]

Important Boat math....

(Cost to pay to have a project done)  - (Cost to do it yourself) = How many new tools you can justify

It is pretty simple math...... 

Garner

[P69]

Pete,

When you drilled the chainplates, did you use smaller bits and work your way  up to the final diameter bit or did you use the one bit (1/2" bit for 1/2" hole)?

Also, what lubricant do you use when drilling SS?

[PeteW]

By all means drill a smaller pilot hole first. I had some tapping fluid I use to drill steel. Lots of pressure and smoke. Try not to burn your bit. Run the drill press on the slowest speed. Curls are good.  Motor oil will work also. Ace Hardware carries cobalt drill bits. Its a very hard steel. Harder than high speed steel (HSS).

After some algebraic manipulation, I think Garner's equation should read:

(Cost to pay someone else to do it) - (cost of material + cost of tools needed) = (money you saved or lost by doing it yourself)

The above equation does not actually comply with GAP as the cost of a capital expense should get depreciated over the life of the tool. But it can be used to justify the expense if after just one job you actually own the tool free and clear.

i.e. I bought a $500 spray painter to paint my house and still saved $1500.  I now own a paint sprayer free and clear. Then I painted my mother's house and a barn with it.

Pete

[Della and Dave]

P69:  Sometimes you need to subtract the beer consumed as well, or add it, I forget.......

With anything other than small holes in stainless, I have found it it is better to drill a pilot.  Much easier to keep your holes aligned, spaced right and in the center.  If you buy a drill bushing of the right size, you can put it in the hole in the old chain late and drill for the pilot through the center.  At least that's what I'm thinking right now to keep the hole spacing right. 

Sometimes when I an drilling stainless or titanium on airplane parts, I make a little dam out of clay and fill it with oil, then drill through the puddle of oil.  As long as you can find your punch divit, it works pretty well.  I have used motor oil, 3 in one oil, triflow, and bo-lube in the past.  The dam trick and motor oil seem to work best for me when it is a challenging hole to cool. Make sure to wear a clean white shirt....

Airplanes usually don't use 316 because of it's lower strength, at least in the annealed condition. You can bump the strength by getting the work hardened version, like 1/4 hard.    Better corrosion resistance though, so I think it is a better choice for chain plates.   Like Pete said, slow drill speed in stainless and clamp your work because at the slow speed, you have a lot of torque and you can loose a finger if you aren't carefully.   

Pete: Are all the mizzen chain plates the same hole pattern below the deck?  With a three hour drive between the boat and the shop, it would be nice to pull one chain plate, and make 4 like it and then replace the other 3 with one trip. 

We don't have chain plate covers on the mizzen uppers for some reason and there are no holes where the would have been, so I assume Polaris never had them.  All the others are stainless with 4 screws but the mizzen uppers have two screws on either side of the plate.  Any idea what that's about? 

[Dale Tanski]

I have an AutoCAD drawing of the chainplates. If you can open it I would be glad to send it to you, or I could print it and FAX it or snail mail it also. To answer your question, yes all of the mizzen chain plates are the same dimensions.

As for what that screw head in your picture is doing there, that is a mystery.  365's did not come with covers on the mizzen plates.  The area for the cap shroud is too conjested to get one in there and it would inhibit the flow of water along the deck to the scupper.  I ended up making one for the lowers where it comes through the teak cap.

Polishing the plates on the end that sticks through the deck is very time consuming and necessary for you being in salt.  It takes the right equipment and technique, (like everything else).  I polished the top 5 or so inches because I had the access to the equipment and then bead blasted the rest. If you could find a polisher in your area it might be a good idea to get a price before you jump in, or have them electropolished. 

Dale

[Della and Dave]

Hi Dale.  A drawing would be great.  That way i cane make them before going to the boat. I just bought steel for the mizzen chain plates.  We have a local steel supplier that serves the oil patch, and they have 316 strip in stock.  Only 32 bucks for 12 feet of 1/4 inch X 1 inch.  I was still wondering about 1/4 vs 3/16, but they didn't have 3/16, so 1/4 is looking good. 

Dave

[PeteW]

Here's the link to the chain plate drawing that I posted awhile back.  It worked for me but I did have to chase a few bolt holes during reassembly.

http://www.pearson365.com/forum/index.php?topic=778.msg3735#msg3735

Here's how the chain plates will eventually fail in Pearson 365. I don't think electro polishing  would have made much difference.



The top section of the plate that gets exposed to salt water is the only part not corroded. That's because it was also exposed to oxygen. Oxygen causes that protective layer of oxidation called passivation to form. Salt water will erode the passivation but the steel continually re-passivates from the endless supply O2.

The 1" or so that passes through the deck gets no Oxygen. This is where the failure will occur. The only way to prevent this is to ensure the integrity of the chain plate cover and its calking. Calking a chain plate leak from the inside is the absolute worst thing to do.



Pete