Hi Adam,
I just did another stack of boxes, but this time I didn’t use any Citrus Solvent. There was much less migration - only 1-2" at most, and some corners showed no migration. However, to my eye, the coverage and penetration of the outer surface was less even, and it was a lot more effort. I used a different brush, but I can’t imagine that contributed to the wrist strain.
The things we do for our bees! 
Dawn
What size Tung oil did you use to complete one coat and how many coats did you apply to get your coloring as I also love the colors.
OK, I know this wasn’t for me, but I have Tung Oil treated 3 deeps, 4 mediums, 3 outer covers and miscellaneous other parts. For a Flow hive, 8oz or 250ml should be enough for 2 coats. Two coats should be enough, unless it looks uneven when you have finished. It goes further and smoother if you dilute the first coat 1:1 with citrus solvent (food grade D-Limonene) http://www.amazon.com/gp/product/B009SSGW48?psc=1&redirect=true&ref_=oh_aui_detailpage_o04_s00
I used Tung Oil from here:
Good luck!
Dawn
I had been looking at the bottle from BeeThinking.com, but this is a much cheaper option from Amazon.
I used the bigger sized bottle, but had a lot left over, so I’m using it now for other projects. There are 2 coats on, not diluted though. I used an old t-shirt to apply the oil, as i do with almost all stains. I let it dry for a long time between coats as well. It isn’t as smooth as it would be if diluted but i don’t mind. I’ve had it outside now, about a week, since its been warm.
Thanks
Tim
I think that is the secret. I used a paint brush, as my father was a paint chemist, and that is what I am comfortable with. However, I think it probably takes a lot more sealant (and elbow grease) with a brush. Plus, it sounds like you are an experienced wood worker. I am not. I just make a few hives, and play with a jigsaw or sandpaper sometimes. I did play with a router this afternoon, but that wasn’t on wood, and I didn’t do a very good job with it. OK, drifting off topic now… 
Thanks to everyone for your information it is really helpful.
Before I discovered this thread I bought a litre of food grade grape seed oil to seal my hive… in conversation with a beekeeper. Now I am not so sure? Any experience. It is surely safe but perhaps the longevity of the seal not great?
Otherwise will have to order Tung oil as suggested from Amazon.
Thanks
I would cook with it, or use it to make salad dressing, but I wouldn’t put it on the hive. Tung Oil “cures” to a dry surface, I don’t think the grape seed oil would do that. Given the price of the hive, I think it is worth investing in the Tung Oil.
Dawn
Dawn, I notice in another post that you mentioned preferring a wax dip if possible which should last 15 years rather than the tung oil which would need to be refreshed every two years. Do you think there is a case for not using anything and letting the wood, which has its own oils, silver naturally. My silver cedar hives are beautiful and look part of the woodland.
Of course, but I have done that in the past with our WBC hives, and I wanted to try something different. Western red cedar is very beautiful when sealed. Who knows, over time I may get bored with sealing, and just let them weather. 
Not particularly you in mind but all these folk who have mentioned all these various oils. 
I suppose the thing is that US and Australian beekeepers are not familiar with cedar hives. They are so common in the UK, but very rare elsewhere. Untreated cedar does fine in the UK, and it does OK in the US, but there just isn’t the experience base. Pine is completely different - it will rot or get eaten within 5 years or so if you don’t treat it. American termites are very determined and a big problem for us, so pine absolutely must be treated with something. As that is the experience base, people are not comfortable unless they are sealing the wood with “something”.
From a personal point of view, I love the colour variations in sealed western red cedar. If you let it weather without sealing, a lot of that is lost. So I am going to enjoy the colours for a few years, at least.
how about using linseed oil ??
You certainly can, but it doesn’t behave like Tung Oil. Tung Oil dries to a hard, dry finish. Linseed oil remains wet. Either way, don’t treat the inside of the hive.
what happens if my friend put it on inside ? will that harm the bees
It is not known to be toxic, but it is not desirable and not necessary. The bees seal the hive themselves on the inside. If your friend put it on the inside, I would wait 3 or 4 weeks before putting bees in the hive, so that most of the oil is absorbed into the wood. I would also wipe out the inside with a clean, dry, cotton cloth.
Dawn
thank you very much … i can see that this forum will be very very helpful
I just put the first coat of Hope’s Tung Oil on my hive but only on the outside surfaces. One question for me was the landing board. Seems like that has direct exposure to sun & the elements so would be smart from a wood preservation perspective to seal it. However, the bees obviously are in direct contact with the landing board. Opinions on sealing or not sealing that? (confession: I did seal it) Thanks!