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Somebody on another forum gave me a tip.

If you wrap the wood in foil you can use a convection oven rather than an autoclave. I did a quick and dirty little test and the results are interesting.

On the left is untreated, on the right is way overdone at 2hrs 360*, in the middle seems indistinguishable to the wood I payed to have done some time ago, which was I think 3hrs at 180C in an autoclave.

The middle strip was 20 minutes at around 280. There’s a wipe of shellac and the color match to the top it’s sitting on is near identical.

I didn’t take any data cause this was just a ‘find out if it catches fire’ test, but at some point I’ll cook up a proper top.

It has the brown sugar smell and definitely the feel of autoclaved wood, however, in the autoclave the wood is also injected with steam which pushes out what I believe is the hemicellulose (?) so I’m not sure if the results are truly the same, but it’s interesting at least.

Being able to do one off’s from the privacy and comfort of one’s own home would definitely be preferable to having pony up enough wood to convince the autoclave man to do a batch of spruce.

Food for thought…

I would guess the irregular stain / blotches are stuff cooking out of the wood? Are they on the surface, ie, removable with sanding?

It definitely does look cooked. It's my understanding that to do it right you have to suck the O2 out of the oven which allows you to get it to a higher temperature above which the would wood normally catch on fire.

T-Tops from suppliers are only a bit more than the regular tops though right? Is there really a cost benefit to cooking your own?

Yes, the staining is surface only, it comes right out.

I believe that by wrapping it tightly in foil, you deprive the wood of the oxygen needed to combust, rather than having to suck all the oxygen from the oven.

I’ve only ever bought one t-top from a supplier, a long, long time ago. Post that, I have been buying spruce in bulk, shipping it to a torrefier, and having it shipped back roasted. I’m not focused on cost benefits. Though not having to come up with 50 tops at once and having them processed would certainly be beneficial to my costs.

Some time back someone posted about cooking tops after (wrapping them and ?) piling sand on them to exclude the air. Another possible use for the gas Barbie?