Tacky/ gummy Danish oil surface on stained, Tasmanian Oak

[Alkahestic]

You need to start sanding at a lower grit, 80, then 120, then 240. From your photos it almost looks like the wood is straight from a bandsaw. I'm going to guess you don't have a handplane or card scraper as those can be used to bring the surface to finish ready state as well.

Your best bet for an even finish is to flood the surface of the wood with your chosen oil, wipe off all the excess 10 minutes later and be thorough. Recoat after the recommended drying time on the product. The surface shouldn't be tacky at all when you go to recoat.

[Chesand]

I would even add 180 grit between 120 and 240 and use a random orbital sander if you have one

[homey]

Luke,

Yes, they are the milling marks. The purpose of going through the grades of paper is that the 80 grit removes the milling marks but leaves moderately coarse scratches. The 120 grit removes the coarser scratches and replaces them with finer scratches - and so on.

I think the finishing guru Bob Flexner has written that if he's using a film finish, i.e. one that sits as a film on top of the wood like poly or lacquer, he stops at 180 grit, but if finishing with oil he may go further. The reason for stooping at 180 with film finishes, I think, is that he believes once the film starts to build there is no advantage in having sanded to an ultra smooth finish.

A very common mistake by new woodworkers is to simply start by using the grade of paper they want to end up with. I was certainly guilty of that myself. However, it is faster and you get a much better finish if you start low (say 80 to 120) then use progressively finer paper.

I highly recommend Bob Flexner's book "Flexner on Finishing", but there are also many good videos on wood prep to be found on YouTube. A card scraper is also a very useful tool and once again YouTube has helpful videos.

Good luck with your finishing.

Brian

[homey]

Here's one of Bob Flexner's articles on wood prep:

Preparing Wood for a Finish @ The Finishing Store News

Brian

[lukeallison]

I've taken everyone's advice on board and I'm very happy with the results so far. Starting again was the way to go.
I started with 180 as it felt really coarse and I couldn't bring myself to go any lower. The result of this was that I had to sand for hours to remove the milling marks. I then used 240 then 340. The stained surface looks so much better this time around.

I'm leaving it for 24 hours in the Queensland summer heat and I'll carefully apply the Scandinavian Oil. Instead of brushing it on I'm going to apply it with a rag, leave for no longer than 5 minutes, wipe off the excess then leave for at least 48 hours. I'll then sand the raised grain with 320 and 600, wipe of the saw dust and apply the second coat.

Is it crucial to ensure that the more absorbent sections of the wood get more oil to ensure the first coat is even?

[LGS]

Hi Luke,

Great to hear that you had success with the sanding and are ready to go ahead. Firstly, don't be too worried about marks left by the low grits. The higher grits (as you have seen) will remove those. If you are going to be sanding a lot in the future, I would suggest the following.

1. See if you are able to have the boards put through a planer/thicknesser to the depth of your choosing. So from a piece of rough sawn timber which is 25mm thick, you could have it planed down to 19 or 16 or 12mm, while smoothing the timber for you as well. I like 16 or 12.
but that's just the depth that I work with when making my projects.

2. Buy a Random Orbital Sander if you are going to be doing a lot of this work. If you are doing only small jobs, then a cheapie will probably get you by, but just don't go too cheap!

3. As to the variable patches on the timber. Before staining, you should wipe the surface to be stained with Metho or to be sure you haven't got oil from your hands all over the workpiece. This will happen! If you sand the board using the 400G and then the 600G it should be fine. If the marks are still there after you clean and restain, then I think you should proceed and see what happens. Sorry about this bit, but if your stain is uneven, the piece won't look like you wan't it too. (lots of learning in what looks like the easiest part of making and finishing things!)

For the finishing oil, smooth strokes up and back with a rag charged with oil is the best way to apply this. Follow the directions regarding number of coats. And don't forget to sand between coats (600g should do.)

Regards, Rob

[lukeallison]

I waited a few days for the stain to dry (>30 degree Queensland weather), wiped the surface to remove any residue with a few different dry cloths then applied the Scandinavian Oil as per the instructions on the bottle. Every instructional video I've seen about applying Danish Oil instructs you to apply the oil, leave for a particular amount of time and then wipe the surface before or just at the start of it going tacky. However, this stuff goes on tacky. Immediately after it is applied it pulls 10-15% of the stain out of the wood and then forms a semi-opaque, tacky film. Now I'm in the process of letting it dry for 24 hours, which is twice as long as the bottle suggests while I run the dehumidifier constantly. Then I'll flip it over and do the other side. So I'm taking precautions but this particular oil is a bit of a nightmare. If I knew that "oil" meant "varnish and oil" I probably never have would considered the product. Hopefully it all works out but the immediate tackiness has me concerned.

[LGS]

Good Luck, Luke. Seems you've been destined to find all the problems with finishing at the one time!! I think all of us feel for you. don't give up!

Regards,

Rob

[soundman]

A few thaughts
# 1 .... Buy yourself a copy of our benovelent dictators book " A Finishers handbook" ... available from the Ubeaut wb site or many wood working shops.

#2 "Dressed timber" is finished good enough for non fussy builders
It will have ripples where the blades cut ...... one of the other issues is on softer timbers as the blades cut they compress the timber so it finishes irregularly as well as having ripples in it.

#3 ..... yeh you do need to work thru the grits ..... mostly with dressed timber I will start at 120.
There are good engineering issues about how far you sand and when.
There have been many tests that show that on film forming finishes goung past 180 or 240 is pointless and sometimes counter productive.
There is no visible improvement past that point and adhesion suffers. .... on "paints" and other builders finishes don't go past 120.


With varuous rubbed finishes they all have their point at which you stop sanding prior to finishing.

The grits above 600 800 ish are mostly used to rub out finishes after they have been applied ..... there is pretty much no point dry sanding any timber with 1200.

you have to be carefull with drying times ....... polly in particular has a recoat window ....... you must recoat before the second curing phase or the following coat do not adhere ....... if fully cured out you must sand before recoating ............. you must know what your recoating windows are for whetever finish you are using.

You must also know how you finish is effected by heat and humidity ....... have a thermomiter and ahygrometer in your workshop ...... some finishes misbehave badly ouytside their temperature and humidity tolerance ..... OR you need to add thinner or use particular thinners to compensate.

cheers

[lukeallison]

Ok I worked out the only way to do this. The instructions on the bottle just do not work as far as I'm concerned. The closest I can get to an even, matte finish is achieved by applying the Scandinavian Oil in a circular motion using 00 steel wool. I rub a liberal amount into the surface for a minute or so then immediately wipe off the excess with a dry rag in one motion then leave it to dry for 24 hours.

The instructions on the bottle suggest to leave it for 30 minutes before wiping off the excess, this is rubbish. The surface becomes tacky within 2 minutes so the result of trying to wipe this off is like dragging a dry cloth through half-set PVA glue. It ruins the surface.

[lukeallison]

PS. Was planning on rubbing 1200 over the surface after my last coat dries to even any blemishes/ inconsistencies with the satin/matte sections. Should I? You may want to reply with "you shouldn't' have these sections in the first place" but I think the real issue is that Danish Oil simply does not play nice with any surface other than raw timber. Maybe I'm wrong but it rubbed into raw timber like a charm when I tested it, which kind of annoyed me after how much difficulty I've had.

[LGS]

Hi Luke,

Sounds like you've cracked it. You're getting what you want. A robust, satin finish to the timber. With regard to using a 1200 paper to finish the sanding, in my opinion, you can't really hurt the result, but it might make it more pleasing. Again, I only speak from my experience.

Good luck. A photo of the finished result would be good.

Regards,

Rob