Ironwood hot plate stand finish

[Fallen Woodwork]

Rather than discarding excess wood while cutting up some blanks I cut three 25mm x 300mm end grain blocks that will end up being simple Christmas gifts.

20211204_181454.jpg

These were cut from a torso piece that was salvaged from a bush fire a few months ago will end up being a winged bowl. I should have cut this up much earlier but have much wood and too little time to process.
20211205_085657.jpgTorso.jpg

After cutting the first end grain block I filled some minor gaps and cracks with CA glue and gave it a sanded to 400 grit to see if it was worth the effort. The timber is not completely dry, micro cracks formed, so I sealed the end grain block with a 50/50 mix of tung oil/mineral turpentine which is when I took the first photo. I will add a further 2 coats of Tung oil over the next 4 days to this test piece.

I expect there to be some further drying and potential for cracking.
I have many more off cuts that could be used as hot plate stands or coasters.
I have sealed the other end grain offcuts with water resistant PVA until they are ready for sanding.

Question 1. Is it possible to prevent further cracking of these end grain blocks?
Question 2. Is there a better non-waxy finish than Tung oil for wood that will be exposed high heat?

I see Kunos Counter Top Oil specifies "Prevents temperature-caused discolouration of light wooden surfaces, e.g. by warm drinks in porcelain cups" so may not stand up to higher temperatures than "warm".

Perhaps Cooktown Ironwood can stand up to such heat regardless of the finish

[dai sensei]

I use Rustins Plastic Finish, water/heat/chemical resistant and you can achieve flat/satin/gloss finish.

The timber will stop cracking provided it is completely dry. Just because it's an old log doesn't make it dry. I slice mine and then oven cure/dry/season them

[Fallen Woodwork]

Thanks Neil

I had a look at the application recommendations: "Ideally 15-25°C. Do not use below 15°C, or in conditions of high humidity"

Given the time of year and location I might not be able to use Rustins any time soon however I imagine there is soon leeway
How do you find applying the plastic coat above 25 degrees or in humidity?

[dai sensei]

I've been applying inside the house in the lounge room with the aircon on if it's too hot or humid.

[Fallen Woodwork]

Very lucky to be able to use the lounge room. The Mrs would go about turning me into a eunuch if I tried that
The volatile odours must be fairly low with Rustins plastic coating?

[dai sensei]

..The volatile odours must be fairly low with Rustins plastic coating?

Actually no, it stinks but only lasts a day, then again I like it

[Fallen Woodwork]

Thanks Neil. It must be good stuff.

I'll have to wait until the dry season to give it a go.

Out of interest - what temperature do you set your oven at and how long to dry timber?

[dai sensei]

Out of interest - what temperature do you set your oven at and how long to dry timber?

Depends on timber species, size and how dry it is to start with. I use my dehydrator or my smoker oven on low temps to start with when green for reasonably stable timber. I often start at 30 for a few days, then 40 for a few days, then 50 until around 10%. For sensitive timbers I slow it down even more. Ebonies and other valuable "look at it and it cracks" type timber, I'll often soak in water for a year or two in plastic barrels (NOT metal) before starting to dry, and even then the temps are very slow.

Once at OMC (outside dry) and seasoned I'll dry at 105C until 0%MC (by weight method, moisture meters are useless b slow 6%MC). Keep in mind dry doesn't mean seasoned, nor destressed, so a lot of factors come into it for larger pieces.

[Fallen Woodwork]

Thanks Neil. It looks like a lot of care, art and science involved. I'm inspired to learn more