Rot and Termites in 6x6 Cedar Deck Post

[stanltod]

The problem:
I discovered rot and subterranean termite damage on a 14' 6x6 rough cedar post supporting my deck.  The post supports a corner of a small 4' x 4' platform at the top of the stair landing that is attached to my screened in porch deck.  Essentially, the 6x6 cedar post is bearing support for about 1/4 or 2' x 2' of the platform, another 6x6 supports the other outer corner and the inner side is attached to the deck header which is supported by other 6x6 posts. 

The history:
The posts, when originally set 9 years ago were buried about 3" into a concrete footing.  A 24" rock wall (backfilled with dirt) was added shortly after.  Rather than cut off the cedar posts and pour piers to the new grade, the rock wall contractor built 10x10 square forms around the 6x6 posts and poured concrete mix into the forms to about 2" above the new grade.  I think they were dry poured because the solid concrete was grainy and weak rather than hard and solid.  I guess this was done in an attempt to protect the cedar from wet earth since the footing was already providing structural bearing support.  Over time the concrete sides cracked and termites were able to enter the cedar post below grade and they bored upward in the core of the cedar post.  By the time I discovered the rot/termite damage when it finally penetrated the cedar post face above grade, they had already bored up about 14" above grade and about 1/3 of the cross section of the 6x6 post.  I supported the deck, dug down to the original footing, sawed the post off just above current grade and removed the previously buried lower 2' of the post , poured a new 12" round pier 24" tall with a 6x6 zinc plated 1" standoff bracket on top to support the post.  The post is 14' tall and has details that make it a lot of work to replace such as notching supporting the platform, a decorative cut top, and railing attached.  That, in addition to it being a $100+ post and everything I hear from suppliers is that new cedar posts they've been seeing are terrible quality.

Next step:
I would like to reconstruct the bottom section of the cedar post where the rot and termite damage occurred before I remove the bracing that is currently supporting the deck.  I have a hollowed out section of post extending up about 14" from the zinc bracket.  At the bracket, about 1/4 to 1/3 of the cross section of the post is missing extending from two corners toward the center of the post in somewhat of a triangle pattern.  This roughly triangle shape tapers smaller as you go up to about 14" where there is no longer any sign of damage.  The bottom of the post is rough and uneven.

The plan:
1. Brush Conserv600 onto the exposed wood surfaces where I dug out the rotted wood, continue until it will no longer absorb the consolidator.
2. Drill some small holes just above where the rot appears to stop and inject/pour ConServ600 into the holes and allow it to penetrate downward until it stops penetrating.
3. Wick some Conserv600 up into the bottom of the post using a tray of some sort to hold the epoxy puddle while it soaks it up.
4. Fabricate and treat with Conserv600 a snug fitting block of cedar to sister into the cavity created from digging out the damaged wood.  Attach sister into void with screws. 
5. Fabricate a bottom "tray" or mold of some sort to create a new level, solid, flat post bottom even with the current bottom of the cut post.  I am basically filling in the voids in the bottom of the post to make a new solid post bottom, as if it had been smooth cut by a saw where the post will rest on the zinc bracket.  With the bracing in place, I have about 1/8" clearance between the bottom of the post and the top of the zinc bracket so I don't have a lot of room for this mold tray.  I need something flat that epoxy won't stick to that I can remove after the bottom of the post hardens and after I have finished my epoxy work.  Maybe a thin piece of plastic or metal covered with saran wrap leveled and shimmed up to the touch the bottom of the post?
6. Fill the gap between the sister and post at the surface with a continuous rolled rope of modeling clay extending just inside the post face to keep epoxy from running out.  Pour Conserv600 in at the top to fill the void between the post cavity and the "sister" piece.  I will probably do this in multiple pours.  Will liquid epoxy bond to cured epoxy?  How long do I wait to pour? 
7. After cured, remove the modeling clay and fill the small gap to the post surface with sandable filler.  Stain the repair with cedar colored penetrant to match the rest of the posts and decking.

The goal:
A level, flat-bottomed post with same or better structural integrity than the original that looks good cosmetically.

The questions:
- Is this the right approach or should I be considering something different?  Should I just bite the bullet and replace the cedar post?
- Is there any significant flaw in my plan?
- How do I get a flat, level bottom on the post?
- How do I make a mold and properly fill the gap between the cedar and the sister piece?
- Should I screw the sister piece in to hold it in place before I pour the epoxy to fill the gap and then remove the screws after I am done? 
- Will liquid epoxy bond well to the cured epoxy?

I've given this a lot of thought, just need to know if I am thinking about it the right way.  I hope this all makes sense, I hate that it became a novel.

Thanks.

[Paul Marlowe]

To whom it may concern,
1. If you use epoxy for this application I recommend the 100 consolidant & 200 patch instead of 600.  You could replace the post instead of filling it, but if you do that the end grain of the new wood should be treated with borates and allowed to dry.  Then apply consolidant to this dried end grain to seal in the borates and seal out the water.  You could also apply epoxy patch to the end grain for more protection.
2. Use an EPDM or similar membrane as a break to the metal bracket.  Keep it wide/wild of the post perimeter and when finishes are complete, cut it the back flush to the post.
3. Lay the EPDM flat onto the bracket and add temporary support to hold it level, if needed.
4. No need for a mold if you thicken the 200 enough to hold the shape desired.  Tool the epoxy when cured and fill in any voids with more patch as needed to match the plane of the post.  The color of the patch is reddish brown.
5. If you use a wood filler/sister piece within the post plane you should dry fit it first with screws then remove it, consolidate the damaged post and new piece, especially the end grain and set it aside. Apply patch to the exposed damaged faces, screw the filler in place and complete the epoxy patch.
6. Our liquid epoxies will bond to cured epoxy but you shouldn't need to do that here.
   

[stanltod]

I was thinking 600 because of its flowability to fill the void and because I thought it would be more structurally sound.  Are you saying that 200 is adequate for this structural need?  Plus I was trying to avoid buying multiple different products due to leftovers and cost.  600 seemed to do everything I wanted to do with one product.
Thanks.

[Paul Marlowe]

To whom it may concern,
1. The 100 will flow like 600 without any thickening agent.  Voids can not be filled with the consolidant unless there is a tight form to hold the liquid in place. 
2. It sounds like 200 would be strong enough for the need you described, especially considering you haven't mentioned any settling.  (The epoxy 200 is strong enough to be used on stud bottoms to extend the length a little, for example.)   
3. You will need some 200-1D thickening agent along with the 600 to fill voids and have it stay in place while curing.  The 200 patch can be tooled after curing but the 600 cures hard and is not easily tooled once cured.  Therefore the 200 repair should be easier to blend in with the surrounding fabric.  The final results should be included in the cost equation.  You might be able to use any extra 100 and 200 on exposed and prepared end grain of boards, posts etc.