Drying different species in a solar kiln

[Peakebrook]

Are there any problems with drying different species or different thicknesses in a solar kiln.

I just had three walnut logs dropped of by a local arborist that I cut and stickered last night.  Any problems drying these with a load of pine or cherry?

These are the first walnut I have ever cut, since not much grows in the northeast.  They sure look nice, but don't want to create any problems drying them.

Thanks

[beenthere]

I'd think, of the three species mentioned, if you dry on the cherry schedule and track samples of each species, you should be able to make it work ok.

Now, that would be the same thickness. 

Adding a lot of variables with multiple/mixed thicknesses. Might be asking for problems.

[pineywoods]

I mix oak and pine in my solar kiln, but I usually air dry for a month or so first. But remember I'm one of those dummies who don't know you can't do that, so I go ahead do it. :

[Den Socling]

I have never operated a solar kiln but I can say that those three species are very forgiving. Also, solar drying can be gentile with night time being "resting" periods for the wood to equalize.

[Rob D]

I have stored wood and dried it in a solar kiln (or polytunnel) for a good while now. The main problem I think is to keep the wood out of direct sunlight as you get drying defects quite easily. Also I'm not so sure the hot temperatures in the day then cooler at night is good for the wood. A kiln in darkness drawing water out in a slow regular way I have found to produce far less problems.

But my advice is make sure your stickered stack is covered with a porous sheet (not plastic) that will let it breath but not let direct sunlight hit the wood.

[metalspinner]

I've been drying mixed loads of air dried woods in my solar kiln with no troubles.  This is a passive solar dryer using only a couple of circulating fans to move the air.  I am in no hurry to get loads out so even the slow drying woods have plenty of time to reach equilibrium MC with the rest of the load.  The dryest I've puled out of the kiln has been 5%.

The biggest mistake I've made was putting in green lumber.  It just dryed too fast.

[Peakebrook]

I did not think it would hurt since it should equalize at night. 

This is the first walnut I have ever cut.  I figured it would be better to put it in as a mixed load, rather than only putting in 600 bf by itself.  The kiln is designed for 3000 bf, with temps reaching 142 F today with a load of pine today.

I will put it in this fall with some cherry I am air drying and see what happens.

Thanks