HELP! - What just happened

[Paul Negus]

I am a novice woodworker trying to make my first coffee table using cherry.  The wood had a low moisture content and I let it sit in my garage/workshop for 3 weeks before starting.  Everything wnet well until I added the tile and overnight - disaster.

The wood sections are joined using yellow glue and floating tenons and I waited about 2 weeks before adding the tile.  There was no sign of any movement.

Overnight the wood parted company in 2 areas and seems to be bowing.

Anybody know what happened, what did I do wrong and how do I avoid this on my next one.

The table legs and apron are all assembled using Kreg pocket holes and will fix to the table top with pocket holes.

[Ken Darga]

Appears to be the joint material expanded between the tiles---

stressing the wood joints, causing separation.

Expansion rates are different in dissimilar materials.

 

[James Sandlin]

Maybe try trimming the tiles a little smaller for more of an edge around and use a lighter weight grout in between them. how are the tiles attatched to the table? thin set? some form of a glue?

[Ken Darga]

I wouldn't trim the tiles---

I'd use a resilient joint compound, (silicon caulk), between the tiles.

[Paul Negus]

I used pre mixed thin set and pre mixed grout, I think silicon caulk might have been a bertter choice or epoxy grout but that is difficult to find in small quantitites and expensive.  Although not as expensive as my mistake!

 

[Ken Darga]

Paul,

Before proceeding, examine other tables with similar construction.

Perhaps you can determine how other similar table designs were constructed.

The tiles could be bonded to a wood substrate with a silicon adhesive/sealant.

Use the grout between the tiles.

Installed a resilient material,

1/4'' dia silicon rod, or the like, around the perimeter of the tiles,

so it is positioned between the wood and the tiles.

Alternate:  nylon rope, as an inset?

The rope would have to be treated, to resist stain---

treat the nylon rope with shellac.

A bonding agent can be used, to secure the rope/rod in place.

Locate the boding material, in the grove, on the underside of the rope,

so to be unnoticeable from the top side.

Alternate 2: Hemp rope. 

Cut the rope, so as to achieve mitered corners.

Shellac---3 coats--- the hemp rope before installation.

The cut ends of the hemp, will have to be bonded, so as to prevent unraveling.