Page 2 of 5 FirstFirst 12345 LastLast
Results 11 to 20 of 42
  1. #11
    Join Date
    Oct 2014
    Posts
    365

    Default Re: Double Diagonal Topside Seams

    Thanks, you have encouraged me to answer my own question with the able support of the interweb.

    West Systems suggest that thinning with a solvent is bad (or at least ill advised) practice. Heat is recommended. Either heating the epoxy (before mixing) or heating the item to be epoxied...or both

    When it comes to syringes others say that any needle is pretty hopeless and using the syringe itself is best, maybe countersinking the entry hole to make a good fit and allowing for higher injection pressure.

    This could be fun!

  2. #12
    Join Date
    Nov 2004
    Location
    West Mersea. north Essex
    Posts
    4,839

    Default Re: Double Diagonal Topside Seams

    sorry - duplicated
    Last edited by davidej; 05-04-18 at 17:36.
    davidej

  3. #13
    Join Date
    Nov 2004
    Location
    West Mersea. north Essex
    Posts
    4,839

    Default Re: Double Diagonal Topside Seams

    I think propanol (propyl alcohol) is a better thinner. It is not as volatile of as inflammable. It is easily obtained on fleabay.
    davidej

  4. #14
    Join Date
    Dec 2007
    Location
    S.W. France
    Posts
    7,673

    Default Re: Double Diagonal Topside Seams

    If you heat poxy to thin it, use the slowest hardener available. Heating the wood is better. But, one has to say, these double diagonal hulls were not expected to last more than a few years. So any left require some ingenuity, or a lot of money.
    In one case I know of, the damaged planks were replaced with sika type joint, then the whole lower hull skinned with poxy/glass. Purists would shudder, but the boat had been out of the water for many years in the dry and the planks were shrunk and cupped. Replacing the whole lot was beyond the skills and budget. Plus, it was not a big project, like a ASR boat.

  5. #15
    Join Date
    Dec 2005
    Location
    Far S. Cornwall
    Posts
    13,335

    Default Re: Double Diagonal Topside Seams

    Hang on, if I'm correct the OP's undercarriage is OK, it's the topsides. If this were some piece of historic memorabilia a solution wouyld be found. If the wood itself is OK then trial and error should come up with something. There was the infamous silicon injection DPC into my cottage which I undertook because the bank manager giving me the loan was also helping the injectiion co with their startup (complete waste). There are products which are designed to creep into small places, and maybe remain flexible.

    Tooth repair for example, ususally wet: https://en.wikipedia.org/wiki/Dental_composite

  6. #16
    Join Date
    Sep 2015
    Location
    Southampton
    Posts
    473

    Default Re: Double Diagonal Topside Seams

    Quote Originally Posted by fisherman View Post
    Hang on, if I'm correct the OP's undercarriage is OK, it's the topsides. If this were some piece of historic memorabilia a solution wouyld be found. If the wood itself is OK then trial and error should come up with something. There was the infamous silicon injection DPC into my cottage which I undertook because the bank manager giving me the loan was also helping the injectiion co with their startup (complete waste). There are products which are designed to creep into small places, and maybe remain flexible.

    Tooth repair for example, ususally wet: https://en.wikipedia.org/wiki/Dental_composite
    You are correct, below the waterline everything is sound so far as I can tell, everywhere I've jabbed with a screwdriver has been rock hard, this in mind is it fair to assume the fixings will be equally sound? I'm not sure what the lifespan of copper fixings is. Johnlilly, to what extend is it possible to survey the bottom of a boat that's copper sheathed?

    What I've been trying to avoid is the considerable expense of a lift out and storage ashore, money which I would prefer to spend on materials. If it comes to it, it would be financially viable (just!) to remove and refasten the outer layer of planking, replacing where necessary and re-bedding on a modern alternative to calico and white lead.

    Someone will probably say if this is an option then it's the obvious solution, however I don't know what the negative effects might be on the bottom planking from spending a long period of time ashore. As far as I know the boat has never spent any considerable time ashore since its refit in the 50s.
    Last edited by PotatoNavigator; 06-04-18 at 08:58.
    Jouet Golif 'Aljonic'

  7. #17
    Join Date
    May 2001
    Location
    South Dorset/moored Poole/lay up Wareham
    Posts
    340

    Default Re: Double Diagonal Topside Seams

    Quote Originally Posted by PotatoNavigator View Post
    You are correct, below the waterline everything is sound so far as I can tell, everywhere I've jabbed with a screwdriver has been rock hard, this in mind is it fair to assume the fixings will be equally sound? I'm not sure what the lifespan of copper fixings is. Johnlilly, to what extend is it possible to survey the bottom of a boat that's copper sheathed?

    What I've been trying to avoid is the considerable expense of a lift out and storage ashore, money which I would prefer to spend on materials. If it comes to it, it would be financially viable (just!) to remove and refasten the outer layer of planking, replacing where necessary and re-bedding on a modern alternative to calico and white lead.

    Someone will probably say if this is an option then it's the obvious solution, however I don't know what the negative effects might be on the bottom planking from spending a long period of time ashore. As far as I know the boat has never spent any considerable time ashore since its refit in the 50s.

    Have you been able to access any underwater planking for testing directly or is it all copper sheathed below the waterline.
    In answer to you question referring to inspecting through copper sheathing the the quick answer is no, you cannot realistically assess the planking condition below the waterline where it is copper sheathed.
    Copper fastenings have a long life....in most circumstances. What can happen is that the internal rove ( the washer over the nail end) becomes very thin and easily comes off or disintegrates and does not hold the nail tight and in effect the rivet fails. Check these, if you can lever it off easily with a screwdriver then that would not be a good sign.
    It might be possible to remove the external skin to access the calico and replace but the removal of hundreds and hundreds of fastenings is not to be taken lightly. The likelihood is that a percentage of the external and perhaps internal skin planking would be damaged as it is probably only 12mm or less thick. If you do not count you own labour and time then possibly it could be possible with a limited budget but it would be an endless task and with the inherent risk that one might just give up half way through making the vessel into a liability and unsaleable. Bear in mind that in order to remove just one plank you would have to access many dozens of fastenings internally and you must be able to access every single fastening which is sometimes near impossible on a completed hull with joinery , engines, etc.. I would strongly advise to investigate a bit more before spending a single penny.
    www.seasurveys.co.uk
    Surveying & Shipwright info on GRP, WOOD & so much more

  8. #18
    Join Date
    Sep 2001
    Posts
    18,583

    Default Re: Double Diagonal Topside Seams

    There are water based epoxies, which would not require the planking interface to be totally dry, might be an idea. to inject that.
    If I agreed with you we'd both be wrong.

  9. #19
    Join Date
    Nov 2002
    Location
    Colwell Bay
    Posts
    5,666

    Default Re: Double Diagonal Topside Seams

    I think its a do or die situation.

    Do nothing and its eventually a one way street.

    When Phil Clapburn rebuilt MGB81/HSL102 and the little one, was it 1502, I think he inverted them all, removed the entire outer planking, cleaned off, epoxied new outer planking on with fastenings of course, then epoxy cloth sheathed them. they seem to be standing up well. (I might be able to put you in touch with Phil)

    Its a tricky construction that's for sure.

    The Americans use a product by 3M called 5200 on the bottoms of their Chris Craft although I have not seen it applied here in the uk much., although a chum in Hythe did it to an American lake boat, I've not seen it.

    Ashcroft boats must be even worse with a 3rd outer layer running fore and aft.

    I've only got 9 layers to worry about.

    i'd love to see a few photos.

    Ben

  10. #20
    Join Date
    Sep 2015
    Location
    Southampton
    Posts
    473

    Default Re: Double Diagonal Topside Seams

    Quote Originally Posted by johnlilley View Post
    Copper fastenings have a long life....in most circumstances. What can happen is that the internal rove ( the washer over the nail end) becomes very thin and easily comes off or disintegrates and does not hold the nail tight and in effect the rivet fails. Check these, if you can lever it off easily with a screwdriver then that would not be a good sign.
    It might be possible to remove the external skin to access the calico and replace but the removal of hundreds and hundreds of fastenings is not to be taken lightly.
    So I popped down to the boat after work to look at some of the bottom fastenings, all of the roves I looked at seemed to be in good condition and couldn't be moved at all with a screwdriver

    There's not a lot of interior left inside the boat other than bulkheads so I have pretty good access to the fastenings on the inside, including in the engine room since there's a couple of feet between each engine and the planking.

    Quote Originally Posted by burgundyben View Post
    I think its a do or die situation.

    Do nothing and its eventually a one way street.

    When Phil Clapburn rebuilt MGB81/HSL102 and the little one, was it 1502, I think he inverted them all, removed the entire outer planking, cleaned off, epoxied new outer planking on with fastenings of course, then epoxy cloth sheathed them. they seem to be standing up well. (I might be able to put you in touch with Phil)

    Its a tricky construction that's for sure.

    The Americans use a product by 3M called 5200 on the bottoms of their Chris Craft although I have not seen it applied here in the uk much., although a chum in Hythe did it to an American lake boat, I've not seen it.

    Ashcroft boats must be even worse with a 3rd outer layer running fore and aft.

    I've only got 9 layers to worry about.

    i'd love to see a few photos.

    Ben
    I think you're right about it being a do or die situation. The opinions on this thread are bringing me round to the idea it might be better to do something drastic now and get the boat sorted for a decent period of time than keep fighting a losing battle.

    I'm confident the bottom is sound, so unless I discover something awful I intend to leave it well alone under its copper.

    I'm familiar with the restoration of HSL102 but it's not a route I'd like to go down if I can help it.

    Visitors are always welcome Ben if you want to come and have a look, I'm interested in gleaning other peoples knowledge and suggestions.
    Jouet Golif 'Aljonic'

Page 2 of 5 FirstFirst 12345 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Latest YBW News

Find Boats For Sale

to
to