Glue for rigging

[Tony Leeson]

Hi, I am new to boat building, yes a huge learning curve, nearly at the rigging stage and having read a couple of books not everybody likes to use CA with some suggestions that shellac is better. Has or does anybody use shellac and is it better, I know CA does make the ropes stiff and brittle. Thank you for your time.

 

Tony.

 

 

[RossR]

I think most use a diluted white glue.  50/50 with water.   I have tried CA and lines will break if under any stress.  I haven't tried shellac for rigging, but I am a big fan for other uses. 

[allanyed]

Welcome to MSW Tony.  Please post an intro about yourself in the new member forum. 🙂

 

CA changes the color of the rope where it is applied, and it can be prone to breakage as Ross mentions because it has low shearing strength.   I believe diluted white PVA or shellac are the most commonly used as they work well and are very easy to loosen with IPA. (not the beer, the solvent 😁)

 

Allan

 

[RossR]

1 hour ago, allanyed said:

I believe diluted white PVA or shellac are the most commonly used

Allan

 

Does the shellac soak into the rope enough that it doesn't show after it dries?  I use a 2 lb cut for finishing the wood, is that appropriate for securing knots?

 

Ross

 

[Jaager]

It probably depends on the material used to form the lines that you are using.

 

The traditional material was plant fiber.  For larger scales, linen/flax yarn twists up into very convincing scale rope.  This is a 'be your own rope works' material.  [Very difficult to find high quality linen yarn now].  Cotton thread is often used and is readily available (or at least has been).  This tread is not spun up the same way as rope so as it comes, it is not a convincing approximation of scale rope.  As a feed choice for a ropewalk it does better. 

For these - shellac or white PVA.  The PVA used for woodwork has a significant concentration of acetic acid.  For archival purposes - bookbinders PVA - pH neutral - is a safe choice.

 

There is a building wave of using man-made / synthetic polymer thread as feed stock for a ropewalk.  This material does not have the same pores/channels/gaps at the microscopic level as cellulose based thread or yarn.  I do not know which bonding agents are compatible.  PVA becomes a series of long chains - intruding into pores and gaps and tangling with each other.  I don't know if PVA has its own version of Tris for cross bonding of the linear chains.  

 

Fibers=> Yarn => Thread => Rope

For linen,  I guess that technically - scale rope is actually thread.  The crushed and combed flax stem fibers are much larger than even cotton yarn.  The difference in feel against skin is probably why cotton became such a big hit with the mass market once an economical way was found to extract the seeds.

[Roger Pellett]

For my last rigging project I bought a small bottle, with the brush on the lid, of clear lacquer based nail polish. I believe that it cost less than $2.00.  It worked great on the linen line and Cotton thread used.  Like CA glue it dries almost instantly.  It is convenient since you don’t have to work with an open bottle.  It works by evaporation as it is a plastic resin dissolved in a solvent.  When applied, the solvent evaporates leaving the resin behind.  While I also like shellac, for rigging nail polish is more convenient.

 

Roger 

[Bob Cleek]

5 hours ago, RossR said:

Does the shellac soak into the rope enough that it doesn't show after it dries?  I use a 2 lb cut for finishing the wood, is that appropriate for securing knots?

 

Yes on both counts. Shellac is dissolved in alcohol. When the alcohol dissolves, the hardened shellac is left behind. Two-pound cut is perfect for our uses.  It soaks into fabric with the viscosity of water. It's invisible when it dries. However, remember also that repeated coats of shellac will build upon one another and create a glossy finish which isn't desirable for modeling.

 

Edited March 9, 2023 by Bob Cleek