Which epoxy is most liquid?

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R.Ems

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My oak sampson post has some splits, and I was considering trying to ooze or drool some epoxy in there, a couple of the splits are wide enough to get the tube of a small medical syringe in there (without the needle ! )
While it is warm and dry weather, before the rain gets in.
Doing it from the top, having first taped the sides of the splits, to stop the glue running out sideways.
I would use slow setting epoxy and maybe warm it up a little bit?
Araldite type tubes would be easiest, as I don't really want to have lots left over after buying a professional kit from West etc.
Runniness is what I need, anyone got any good brands to suggest? Cheers for advice.
 
A little acetone can thin epoxy. Not sure about the quantities but maybe experiment.

I always use the cheapest stuff I can find on Amazon. It's pretty runny and it sets fine.
 
I buy the cheap pound shop tubes and add a small amount of acetone when I am casting replacement parts for vintage radios.
It goes very runny very quickly!

You will need to use a heavy duty tape and clamp a piece of wood against it as well or it will go everywhere you don't want it.
I would wrap in cling film first to get a good outside finish and have something that will peel or rub off easily.
Wash the splits out with acetone first to get a good bond. They will not be clean enough as they are.

Nail varnish remover is not pure acetone, there are other things added.
 
Boater Sam said:
I buy the cheap pound shop tubes and add a small amount of acetone when I am casting replacement parts for vintage radios.
It goes very runny very quickly!

You will need to use a heavy duty tape and clamp a piece of wood against it as well or it will go everywhere you don't want it.
I would wrap in cling film first to get a good outside finish and have something that will peel or rub off easily.
Wash the splits out with acetone first to get a good bond. They will not be clean enough as they are.

Nail varnish remover is not pure acetone, there are other things added.
Click to expand...
Cheerss for your expert advice!
 
RJJ said:
A little acetone can thin epoxy. Not sure about the quantities but maybe experiment.

I always use the cheapest stuff I can find on Amazon. It's pretty runny and it sets fine.
Click to expand...
Thinning epoxy =less strong epoxy.
Heat thins epoxy along with setting it more rapidly.
 
I would recommend that you use West system epoxy. It was formulated at its outset to be used to bond wooden component. i believe that West is an acronym for “wood epoxy saturated technology” but couldn’t find any reference to that on the West website. Anyway, you will find that West epoxy will readily find its way into the grain and cracks of any wooden object. I would suggest that you do not attempt to fill all the cracks in one go. Much better to put a thin layer of West epoxy over all the surfaces to be filled. A surprisingly small amount of the epoxy will capillary into any crack. Then, before it has become fully cured add sufficient filler material (micro balloons are good) to a mix to make it thixotropic. It can then be trowelled into the cracks until level with the surface. With that technique most of the mess caused by runny epoxy can be avoided.

Mike
 
A vote for West epoxy, it's very low viscosity, warm to about 30-35 deg C before you mix. If you mix a lot it can go into thermal runway and even catch fire. Use a flat and open mixing vessel with a large surfaces area. I use foil food trays.
 
West System Epoxy - or Laminating Epoxy ... both are designed to wet out glass fibre.

As another said : Anything added to 'thin' the resin also weakens it. Applying heat makes it thin - but also speeds up the setting. Better to get a proper laminating resin and not play with its chemistry !

There is another resin you could use - PU resin - get the exterior variety, brands are : Gorilla Glue, Bison PU Max, local B&Q / Wickes etc. will have a generic version - do not thin or alter it ... with a wedge in the 'crack' - allow the PU resin to migrate into the joint ... it is much slower setting than epoxy - so there's no rush to finish. Once its in - remove the wedge. Wrap with cling-film and then with flat pieces of wood - clamp it hard forcing the resin into all ... Leave it for 24 hours to set.
Remove clamps / film etc. and then sand if necessary. The PU resin foams up into all the crevises etc. providing a strong action. That foaming can be high pressure and those flats of wood and clamps are important. It can be trimmed with sharp knife where it comes out ..
 
R.Ems said:
My oak sampson post has some splits, and I was considering trying to ooze or drool some epoxy in there, a couple of the splits are wide enough to get the tube of a small medical syringe in there (without the needle ! )
Click to expand...
Perhaps you should investigate the properties of oak before injecting a rigid substance in to the splits. I remember being told that it is a very mobile timber and naturally has splits along the grain that open and close with seasonal changes in moisture content.
 
srm said:
Perhaps you should investigate the properties of oak before injecting a rigid substance in to the splits. I remember being told that it is a very mobile timber and naturally has splits along the grain that open and close with seasonal changes in moisture content.
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Yes cheers, that's a very good point. Splits in the oak stem etc get filled with linseed oil putty for that very reason, it can be squeezed out as the wood swells after a long lift-out.
I don't think the sampson post will take up in the same way unfortunately; and rain is getting down there.
It's hard to know what's best to fill the cracks with, but I can't leave it alone.
I will put a lead or copper cap on it when the cracks are filled anyway.
 
R.Ems said:
It's hard to know what's best to fill the cracks with, but I can't leave it alone.
Click to expand...
Perhaps a flexible adhesive sealant plus the traditional copper cap (also bedded in the sealant). The oak will continue to move and eventually break away from an epoxy plug leaving a gap to hold moisture.
 
West got the wooden boat building back on track and there are now many resins available, often much cheaper. I use a Resoltech water based one that was specifically formulated to reinforce old timber in buildings where replacement was tricky. It gets in and replaces dampness in dubious timber which is not yet structually unsound. But needs to have the rot stopped.
Araldite has filler already mixed in, so not the best choice. If you have to do this (other solutions exist) then a resin with a slow hardener warmed a bit would do.

The putty filler for masts idea is to keep fresh water out, so the same. Shakes, as they are known, are usually not a structural problem in grown masts, but lead to water doing it's thing. But, you really need to look at replacing the post if it getting very bad.
 
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