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Jonatham Reynolds
01-13-2017, 02:28 PM
After a lifetime of wanting to do this, I am finally building a small clinker sailing workboat (Oughtred's Tammie Norrie design) for fun, fishing and general utility. It will be hauled out between trips, so I wanted a finish that would allow easy water take-up when re-launched, and would be a good preservative too. The traditional tar/linseed oil mix seemed to tick all the boxes, and - before anyone says it - I don't mind either the smell or what it does to your clothes.

I am unsure what adhesives I can use with this finish. Seems I have to consider the finish before I have even fastened the keel. I understand that epoxy resins don't take well to long exposure to oils, which rings true with my experience in other contexts. Resorcinol (which I have) requires a control over temperature that I simply don't have in the big cold barn I am using for a boat shed. What else can I use?

The main issue is the centreline structure. John Leather (Clinker Boatbuilding) instructs the builder to 'bed the upper surface of the keel and lay on hog', but he doesn't say what to bed it with. I'm not clear whether he means bed it with adhesive, or with a bedding compound, which in the days of tar and oil would have been red lead/putty (which I also have). Apart from the fastenings, were keels glued in those days, and if so, what with?

Or, can anyone recommend a combination of finish and adhesive that would fit the bill?

Thanks in anticipation for your thoughts.

Peerie Maa
01-13-2017, 02:45 PM
Leather's Clinker Boatbuilding is entirely traditional. No glues were harmed in the writing of that book. Use putty or non hardening mastic and you will be fine. You might want to consider mixing a little tallow into the putty, to stop it hardening off

skaraborgcraft
01-14-2017, 02:52 AM
^ What he said. No need for any glue at all in a small boat.....or was you intending to laminate some of the curved parts rather than hunt down grown timber? I own a completely tarred boat, and none of it is glued, just bedded and fastened well.

David G
01-14-2017, 12:52 PM
Yes - if you are set upon the traditional route - stay with it. Mixing and matching technologies is not for the beginner. Nick will have a better sense of what's available on your shores... but I'd tend toward Dolphite, or Boatyard Bedding Compound.

As an aside - just in case you hadn't considered the option - if your build the boat with glued plywood lapstrake (leaping forward to much newer technology: plywood; epoxy) you won't have to wait for the boat to take up every time you launch.

Lugalong
01-14-2017, 07:00 PM
After a lifetime of wanting to do this, I am finally building a small clinker sailing workboat (Oughtred's Tammie Norrie design) for fun, fishing and general utility. It will be hauled out between trips, so I wanted a finish that would allow easy water take-up when re-launched, and would be a good preservative too. The traditional tar/linseed oil mix seemed to tick all the boxes, and - before anyone says it - I don't mind either the smell or what it does to your clothes.

I am unsure what adhesives I can use with this finish. Seems I have to consider the finish before I have even fastened the keel. I understand that epoxy resins don't take well to long exposure to oils, which rings true with my experience in other contexts. Resorcinol (which I have) requires a control over temperature that I simply don't have in the big cold barn I am using for a boat shed. What else can I use?

The main issue is the centreline structure. John Leather (Clinker Boatbuilding) instructs the builder to 'bed the upper surface of the keel and lay on hog', but he doesn't say what to bed it with. I'm not clear whether he means bed it with adhesive, or with a bedding compound, which in the days of tar and oil would have been red lead/putty (which I also have). Apart from the fastenings, were keels glued in those days, and if so, what with?

Or, can anyone recommend a combination of finish and adhesive that would fit the bill?

Thanks in anticipation for your thoughts.

Since you say that the smell and messiness of tar is not a problem, priming the underside of the keelson with tar goes without saying, and a bitumastic bedding compound will do just fine after this. I have previously obtained and used a tar putty, which could be worked on as thick or as thin as one preferres. But this product might be hard to find now and I have more recently had to use a brush on watertank sealing bituminous liquid, which does thicken up considerably when left open to the air and should then also do the trick. Fastenings (keel bolts and copper rivets are relied on for structural integrity anyway (with old time clincker construction), so glue can be dispensed with

Jonatham Reynolds
01-16-2017, 11:26 AM
Many thanks, all. In answer to the points made:
- Yes, I am set on the traditional route, simply because I like wood and hate working with resin.
- I have seen a bituminous black pudding filler available somewhere, which seemed to be coal tar + cement. I hope not to have loose enough joints to make that necessary!
- Mention of fastenings raises another question, but I'll start another thread for that.

Thanks again.