Bowls drying unevenly

[Chriscb]

Afternoon,

Hit a problem with some bowls that have dried unevenly after a second coat of finishing oil. Primarily Ash and Sycamore but a couple of Cherry as well. Oddly not all bowls in this batch of 12 have the issue. I have processed about 40 bowls before with out problems so this is a real head scratcher.

Briefly my process is to finish the bowl to 320 grit, leave a day or so to settle and then wipe over with 0000 wool, clean off the dust with meths, leave to dry. Apply finishing oil by hand on both surfaces and then pop into a drying tent. Wipe off excess around 15 minutes later. Second coat applied when the first coat is absolutely dry using same technique, subsequent coats as well until finish is shiny but not glass like.

The images show some examples - they look silvery because of the reflected light, but really the areas are matt as seen on the base of the cherry platter.

Any ideas?

Thanks.

Chriscb

 

[Penpal]

Beaut grain on the Cherry platter. So many good reasons when finishes fail to respond all over,difficult to see the reasons from here.

Peter.

 

[wm460]

Is the wood dried, no sap leaking out?

 

[Chriscb]

Peter - the grain is stunning - more bowls in the batch turned from the same cherry. I’ll show them later.

Mark - all of the bowls were at around 13% moisture at turning stage, and once turned were left for around 4 weeks in large paper sack filled with wood clippings before the finishing process. Moisture was around 11% at the point. So, yes I think they were pretty dry.

Tempted to rub them down to bare wood with coarse wool and start again.

Chriscb

 

[Dalboy]

There could be many reasons some torn grain which you did not see which will give a colour difference. bruising the wood by rubbing the bevel too hard can also allow the oil not to penetrate properly. Even getting something on the wood which will not allow the oil to penetrate.

In some of the pictures, it looks a little like torn grain, difficult to see properly due to some of the reflections.

 

[Chriscb]

Thanks for your thoughts Derek. Seems like a solution could be to start over and see.

Chriscb