Refitting Wooden Mast ( Help )

[sailsearchsurf]

A buddy and I purchased this 63 Hereshoff 28. We have pulled the mizzen mast and stripped back all the varnish. We figure the mast is hallow and the caps have begun to de-laminate. We were thinking of using West System 105 injected into the cracks and clamp it back togethewr and then do 10 coats of Bristol Varnish. However we seem to think the bonding agent is Sikaflex(sp?) Should we using something else that is able to permit expansiona and contraction? We believe it is made of Douglass Fir as well. Thanks for any advice you have to share.
Geoff

[vintageray]

If you already have the old varnish off and the mast is outside don't fool around for too long or the joints will start to separate more. Clean out all the old dried up adhesive with a saw blade. I applied all the CPES that mine would take. After that cured I injected T-88 structural adhesive into the sparated joints and clamped them shut. Am now applying Z*SPAR 2015 Flagship Varnish. Be sure all the old varnish is removed before painting on the CPES. It will lift any old varnish left on the spar. Also, allow the CPES to cure completely before varnishing the mast.

[smurphny]

It may be Sitka Spruce. I'll bet West will work very well. It has good flexibility and is easily workable, probably a lot stronger than the original animal glue of some sort. The joints on a mast like this are usually not simple lap joints but are ?half rabbeted? (I forget the name). In any case, getting glue in may not be so straightforward. Squirt it with a syringe and work the wood before clamping. Getting it clean may also be difficult. Ditto on not leaving it stripped to get wet. A good UV spar varnish is essential.