Wipe on Poly/Tung Oil effect on glue strength

[rdsaplala]

Hi guys,

 

Just a small query for those with experience using these two products.

I am contemplating on treating my wooden fittings/ railings/ mouldings with either of these products prior to gluing them to my ship's hull but would first like to inquire if this carries the risk of producing a weaker bond between the glued parts.  I am using PVA  and CA glues. Thanks in advance for the help

[Cap'n Rat Fink]

Hey Aldo,

     Yes they do effect the bonding of 2 pieces of wood. It's best to glue where you can before you add any type of finish(even wood stain) IMO. Where you can't , finish it then just sand where the 2 pieces of wood meet and you should get a very good bond. Hope this helps buddy.

 

take care

[rdsaplala]

Hi Mario,

 

Thanks very much for the prompt reply my friend,  I will follow your recommendations

[augie]

Agree with Mario.  However, if you can't sand the area because it's too small or inaccessible, carefully poke some small pinholes there.  This will help the glue penetrate and greatly improve adhesion.

Edited April 21, 2013 by Augie

[rdsaplala]

Thanks Augie, that's a very neat tip, perfect for those nooks and crannies otherwise unreachable by sandpaper

[JPett]

Ahoy Aldo

 

You can also use an epoxy. It will provide a superior bond which is especially important for the smaller parts you mentioned

[Modeler12]

I agree with a lot that was said above. But when you think about Tung Oil, for example, it is an oil and would not be too good for adhesion with PVA. Epoxy might do it for you, but why not consider a water-based finish? I have used water-based polyurethane for years and even glued parts together with that coating (after a light sanding) using carpenter's glue (not white glue).

 

JPett mentioned General Finishes as a good manufacturer. And indeed they have all sorts of good products including the water based versions I mentioned. Check 

http://www.generalfinishes.com/retail-products/water-base-top-coats-sanding-sealers/high-performance-polyurethane-topcoat#.UY78raKsiSo

 

 

 

 

[ChrisLBren]

Ive used 100 percent Tung Oil effectively - all you need to do is sand the area you want to glue lightly.  Then PVA should do the trick.  Once dry you can re apply the tung.  I did this to positive effect on my Confederacy, when i needed to sand areas on the interior bulwarks to glue the pin rails.  

[Jaxboat]

Adhesives (Glues) bond in two ways: chemically and mechanically. A rough surface provides a good surface for mechanical bonding. Chemical bonding depends on the chemistry of the surfaces to be bonded as well as the chemistry of the adhesive. I read the labels of my adhesives to determine what materials they can and can't bond. I try to keep surfaces that I am bonding free of paint or sealers as much as possible. I find this usually allows me to achieve sufficeint bond strength with the proper adhesive. Hope this helps

Jaxboat

[Landlubber Mike]

I agree with a lot that was said above. But when you think about Tung Oil, for example, it is an oil and would not be too good for adhesion with PVA. 

Interestingly, I've found that with Tung Oil, I've been able to use PVA but not CA.