External chainplate relocation questions General Forum Forums

avatar

Please consider registering
guest

sp_LogInOut Log In sp_Registration Register

Register | Lost password?
Advanced Search

— Forum Scope —






— Match —





— Forum Options —





Minimum search word length is 3 characters - maximum search word length is 84 characters

sp_Feed Topic RSS sp_TopicIcon
External chainplate relocation questions
avatar
mgav451
Member
Members
December 6, 2017 - 10:25 pm
Member Since: September 27, 2017
Forum Posts: 143
sp_UserOfflineSmall Offline

since a lot of owners have done this I need a few pointers if any one has. I have a 77 de 32 cutter with the internal leaking chainplates. My plan is to have port town foundry make me some bronze one to mount externally. I have a few questions. There’s the little ridge or lip where the rub rail is outside on the hull. ( don’t know how else to describe it, its where the stripe is) do I just grind it flat or do I have the plates made to go around and over that? Also when I remove the old ones I will be using them as backing plates on the inside. Is this how every one has done this? I can use the internal plates as a pattern to send out and have. New ones duplicated in bronze. Any pointers?

Print Friendly
Avatar
Scott Carle
Admin
December 7, 2017 - 9:16 am
Member Since: October 10, 2009
Forum Posts: 1480
sp_UserOfflineSmall Offline

I would not design external plates to go around the lip. I would grind that down. You don't want to introduce any stress points in the chain plates because of a changing profile right where the plate bends slightly already as it changes in plane from up the hull to in line with the angle of the shrouds. Probably not a huge issue in weakening a thick piece of bronze anyway but we know that angles, corners and zones where the profile of metal changes and is under cyclic stresses are breading zones for developing cracks. I would make sure that the  chain plate comes up the hull flush against it all the way to the very top edge of the fiberglass. Then your angle change to be in line with the shrouds. The cap rail simply needs to be cut out so that the chain plate doesn't touch it on that edge.

Scott

Print Friendly
Scott Carle DE38 Cutter s/v Valkyr
avatar
mgav451
Member
Members
December 7, 2017 - 12:18 pm
Member Since: September 27, 2017
Forum Posts: 143
sp_UserOfflineSmall Offline

Sounds good. I assume the old chainplates will conform to the hull and can be used as the old ones. .I'm gonna need some pointers on this compression post to. I think they must have been drunk when they designed that. What a bad design that is. It's not even under the mast and it's not inline with the landing under it. Where it ties into the shower pan/ head step is all crushed and it's not even resting on the lower post in the bilge area. IM thinking I'm gonna cut a 4x4 hole in the deck right over the current wooden post then cut a 4x4 hole through the head step/ shower pan area. Pull out what they thought was a compression post. Put a piece of g10  in the bilge area then slide a 4x4 stainless box beam to rest on that and cantilever the top fwd to rest under the mast. Still trying to figure out how to tie the bulkhead and shower pan etc into this to make it look good.

Print Friendly
Avatar
Scott Carle
Admin
December 9, 2017 - 12:50 pm
Member Since: October 10, 2009
Forum Posts: 1480
sp_UserOfflineSmall Offline

You will just need to cut off the top of the old chain plates where they bend in.. no use for that part and it would extend up through the cap rail from inside. 🙂

 

My compression post and above and below seem to be in good shape with no deformation at deck or below the sole so I have never taken it apart. would not have thought it was out of line like your describing. There area few posts on this topic and maybe some stuff on the main website. Do a good search for compression post and see what turns up. I'm pretty sure there are some pictures of stock and upgraded  versions/projects for you to look at. I'm having trouble believing that yours is stock if it isn't inline with the mast and the footing in the bilge under the sole. I would say the stock setup could have been better designed based on a lot of people having to repair theirs but based on it taking 20 to 30+  years for most of them to start having issues and never having heard of a failure in use of one then maybe they were well engineered to be safe for the boat but not for lasting forever. There are a lot of areas in these boats that are like that. Actually almost all boats are like that. I can see where if you built every thing to be maintenance free forever that the cost would go through the roof.. 🙂 kinda what owners are for. To go behind the engineers and rebuilt it to last forever 🙂

Print Friendly
Scott Carle DE38 Cutter s/v Valkyr
avatar
mgav451
Member
Members
December 11, 2017 - 8:22 am
Member Since: September 27, 2017
Forum Posts: 143
sp_UserOfflineSmall Offline

I will do some searching on the compression post issues hopefully it won't be so bad. . I have got alot done on the boat so far I'll post some pics soon.

Print Friendly
avatar
jimha
Member
Members
December 11, 2017 - 10:02 am
Member Since: February 13, 2016
Forum Posts: 70
sp_UserOfflineSmall Offline

Moved chain plates to the outside of hull about 12 yrs ago.  Used the same chain plates, but polished and inspected very carefully.  Had to replace two of them due to cracks in stainless.  Used most of the same bolts and original nuts, but did change some of them.  No need for backing plates, as the hull has been reinforced in this area and there was no sign of deformation of holes in hull.  Used the old chain plates as a pattern for making the new ones.  Have fun making the square holes.  Used as small square file.  Wasn't that big of a deal.  Angle of bend was duplicated using a big vice.  Slight adjustments in angle are taken up buy standing rigging.  Used an angle grinder on outside of the hull to make the chain plate lay flat against the hull.  All and all a very easy job which stopped those pesky deck leaks.

 

Cheers and beers,

Jim

Print Friendly
avatar
mgav451
Member
Members
December 25, 2017 - 3:01 pm
Member Since: September 27, 2017
Forum Posts: 143
sp_UserOfflineSmall Offline

I just pulled my chainplates out. You said you just ground that little “rib” out? Almost looks like it’ll leave a hole there if I grind it flush?

Print Friendly
avatar
jimha
Member
Members
December 29, 2017 - 12:26 pm
Member Since: February 13, 2016
Forum Posts: 70
sp_UserOfflineSmall Offline

@mgav451

Don't know about that extra "little rib". Perhaps you have a male boat and I have a female boat.  )  The important thing is to have the chain plate flush to the hull.  Did have to grind off part of the wood cap rail, and the poor excuse for a rub rail.  Have fun.

Cheers'

Jim

DSCF1379.JPGImage Enlarger

DSCF1381.JPGImage Enlarger
DSCF1382.JPGImage Enlarger

Print Friendly
sp_PlupAttachments Attachments
avatar
mgav451
Member
Members
January 8, 2018 - 1:30 pm
Member Since: September 27, 2017
Forum Posts: 143
sp_UserOfflineSmall Offline

Ohh yes thanks that’s exactly the picture I was looking for. And the “ rib” I was speaking of was the rubrail (where the paint transitions from blue to white). Looks as if It will grind out and not leave a hole open there if so I guess I’ll fill it in from there.

Print Friendly
avatar
mgav451
Member
Members
January 13, 2018 - 12:45 pm
Member Since: September 27, 2017
Forum Posts: 143
sp_UserOfflineSmall Offline

This is what I was afraid of! Maybe you guys have a solid rub rail? Or yours was locally filled in? Hmmm should I be afraid of structural integrity compromised here? Advice?20180113_122627.jpgImage Enlarger

Print Friendly
sp_PlupAttachments Attachments
avatar
mgav451
Member
Members
January 13, 2018 - 1:14 pm
Member Since: September 27, 2017
Forum Posts: 143
sp_UserOfflineSmall Offline
Avatar
Scott Carle
Admin
January 13, 2018 - 3:28 pm
Member Since: October 10, 2009
Forum Posts: 1480
sp_UserOfflineSmall Offline

It looks as if it is a hollow fiberglass tube where you cut into it. Is that correct? hole doesn't go all the way into the inside of boat?

 

If so then I would think just make some epoxy bog and use a little glass to fill it in and shape it to be flat at the external hull level and shape the protruding part on either side  to look nice. I don't think you would have lost a huge amount of structural strength. Maybe backfill the hollow inside of tube for a few inches on either side with glass and epoxy to give it rigidity right there.

 

Scott

Print Friendly
Scott Carle DE38 Cutter s/v Valkyr
avatar
mgav451
Member
Members
January 13, 2018 - 3:42 pm
Member Since: September 27, 2017
Forum Posts: 143
sp_UserOfflineSmall Offline

Yes that's the plan however I have the hull liner in there so I can't really get at it. Plus it's up in the toe rail nomans land there where you need a contortionist to get hands into. Should be ok. I used 3/8 bronze for the plates drills so easy and bends so easy. Hope the holes don't elongate. I didn't use cast bronze as you should but I hope it's gonna hold just as good. Im not sure the difference between the 2.These really are nice looking boats! I got painting and cosmetics to do but with this compression post and chain plates she should be ready for a beating! I did notice the pics of others chain plates there's 5 bolts as opposed to 4 mine are 24 iinches long 1&1/2 wideand 3/8 thick same as the old SS ones just 3/8 rather then a 1/4 inch. Think I'm ok? I've got the mast down holy hell that thing is like a telephone pole very roubust which makes me happy. I guess the cutter rig allows for smaller standing rigging?  I've got 7/16 pins on the stays and shrouds and 1/2 on the fore and aft. Seemed a little on the small side from what I'm used to seeing. 

Print Friendly
avatar
mgav451
Member
Members
January 13, 2018 - 3:44 pm
Member Since: September 27, 2017
Forum Posts: 143
sp_UserOfflineSmall Offline

20180113_141905.jpgImage Enlarger

looking sssssalty

Print Friendly
sp_PlupAttachments Attachments
Avatar
Scott Carle
Admin
January 13, 2018 - 5:01 pm
Member Since: October 10, 2009
Forum Posts: 1480
sp_UserOfflineSmall Offline

mgav451 said
 I used 3/8 bronze for the plates drills so easy and bends so easy. Hope the holes don't elongate. I didn't use cast bronze as you should but I hope it's gonna hold just as good. Im not sure the difference between the 2.

You really need to know what the tensile strength of your bronze is and that it is suitable to the loads your going to be carrying on it. I love good bronze. maybe a Silicon Bronze etc..  3/8 sounds pretty good thickness of the top of my head but it's been a while since I did those numbers. This is an area you don't skimp in and make sure it is the right type of bronze and the right thickness. As to elongation of theholes.. only three reasons that should happen.

1. it is a softer bronze that deforms.

2.& 3. the holes are not perfectly round and exactly the diameter of the pins. The pins should fit snugly and the tension on the holes should be inline with the length of the chain plate. If it is pulling unevenly on the pin or the hole and pin don't fit snugly, over time the movement and tension will wallow the hole out and you will get more and more movement till something gives.

Print Friendly
Scott Carle DE38 Cutter s/v Valkyr
avatar
mgav451
Member
Members
January 13, 2018 - 5:11 pm
Member Since: September 27, 2017
Forum Posts: 143
sp_UserOfflineSmall Offline

Tensile strength for 304ss is 70,000lb 

Bronze is 60,000

I looked into it and seems to fit the bill

Print Friendly
avatar
jimha
Member
Members
January 14, 2018 - 9:27 am
Member Since: February 13, 2016
Forum Posts: 70
sp_UserOfflineSmall Offline

Looks like difference in rub rail is one of the differences between a DE32 and DE38.  Not a big deal.  If you are going to change your standing rigging, a few tips that saved me $1000.  There is a firm in Connecticut that sells 1x19wire made of Nitronic 50 stainless.  A good upgrade for little money.  I used the same thickness of wire as the fore stay, for all of the rigging.  I ordered the connectors (Stay lock) from a mail order house in England for a substantial discount to US prices.  Pick up a British magazine to get phone numbers etc.  Worth a look.  To cut the wire, I used a vice, some masking tape,  and a 32 tooth hacksaw blade.   Easy peasy.

Cheers and beers,

Jim

Print Friendly
Avatar
Scott Carle
Admin
January 14, 2018 - 10:29 am
Member Since: October 10, 2009
Forum Posts: 1480
sp_UserOfflineSmall Offline

I did the same thing when doing my rigging.. moved up everything from 1/4 inch to the same size as the upper shrouds. kept it simple going to all stay lock fittings top and bottom and didn't add but a couple lbs to the weight aloft as it was just the lowers and whisker stays that  changed if I remember right. That way I could carry one size of replacement wire and spare fittings. I think that the bob stay was the only other size and at it was comparatively huge.. just the two fittings for it sucked for cost.

Print Friendly
Scott Carle DE38 Cutter s/v Valkyr
avatar
mgav451
Member
Members
January 14, 2018 - 8:49 pm
Member Since: September 27, 2017
Forum Posts: 143
sp_UserOfflineSmall Offline

Also the factory made the holes square in the hull. So this isn’t as easy a job as I thought......errrrr so frustrating simple things 

Print Friendly
Forum Timezone: America/New_York

Most Users Ever Online: 120

Currently Online:
10 Guest(s)

Currently Browsing this Page:
1 Guest(s)

Members Birthdays
sp_BirthdayIcon
Today None
Upcoming None

Top Posters:

Jonathan Oasis: 174

bobmcd625: 165

CAE: 150

mgav451: 143

Rick: 94

svbodhran: 84

Member Stats:

Guest Posters: 7

Members: 364

Moderators: 1

Admins: 1

Forum Stats:

Groups: 3

Forums: 13

Topics: 744

Posts: 3833

Newest Members:

Spirare, BradHartliep, Duncan, MistyDawn, realitysailing, Kwally@sbmn

Moderators: Patrick Twohig: 134

Administrators: Scott Carle: 1480