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View Full Version : Tacky/ gummy Danish oil surface on stained, Tasmanian Oak



lukeallison
8th January 2017, 09:58 AM
I'm a newbie to woodwork and surprised myself by successfully creating an even Black Japan stain on some Tasmanian Oak. I then decided to finish it with Danish Oil. Somehow I arrived at the decision that I should brush on a heavy coat of the oil and leave it until it dries. A week later the wood has an inconsistent tacky and shiny finish and the grain seems to have risen. I've read that wiping down the surface daily with mineral turpentine or methylated spirits will eventually remove the tacky surface. The issue is that the wood is also stained and in the small section I tried this on the turps stripped about 25% of the stain.
TLDR: What can I do to remove the tacky/ gummy Danish Oil finish from Oak without removing the stain?

Stained:

403874

Stained and Oiled:
403875

403876

soundman
15th January 2017, 11:39 PM
when you say "black Japan" exactly what does that contain ...... it occurs to me that what ever it is stops the poly from going off.

My recomendation is not not concern yourself with the stand a scrub the thing with GP laquer thinner and start again ..... when I say scrub I mean it.

cheers

lukeallison
16th January 2017, 08:30 AM
when you say "black Japan" exactly what does that contain ...... it occurs to me that what ever it is stops the poly from going off.

My recomendation is not not concern yourself with the stand a scrub the thing with GP laquer thinner and start again ..... when I say scrub I mean it.

cheers

I haven't considered that. I mean Feast Watson Proof Tint Stain (Japan Black colour). I applied that, let it dry for 24 hours then applied the Feast Watson Scandinavian Oil (Danish Oil). However, when I say applied the DO I mean I painted on a thick layer ensuring all surfaces were very wet and never wiped the excess off. I can see that the poly is actually hardening more and more as each day passes and absorbing a little more into the wood, leaving an uneven, semi-glossy finish. After trying Mineral Turpentine, Methylated Spirits, Acetone and eventually more Danish Oil in an attempt to strip the wood back I realised that it would be much more cost-effective to buy another piece of wood and start again, which I've done. Now I'm worried that I'll have the same issue due to the Proof Tint and Scandinavian Oil interacting. :o

I'll do a test on some scrap. :2tsup:

Toymaker Len
16th January 2017, 04:50 PM
All oils have to be wiped off thoroughly before they dry. brush on, leave for ten minutes and then wipe off, leave for a day or two then repeat. If a thick coat has hardened then it needs to be scraped back until all gone then start again. If this removes a lot a stain then you will have to restain or possibly add the (oil-based) stain to the finish oil that you are using.

lukeallison
16th January 2017, 04:58 PM
All oils have to be wiped off thoroughly before they dry. brush on, leave for ten minutes and then wipe off, leave for a day or two then repeat. If a thick coat has hardened then it needs to be scraped back until all gone then start again. If this removes a lot a stain then you will have to restain or possibly add the (oil-based) stain to the finish oil that you are using.

Yeah, yeah, yeah I'm past that. I'm all good now aside from the possibility that the stain and oil aren't playing nice with each other. Doubtful that will be a problem but I'll test soon.

LGS
16th January 2017, 05:09 PM
That piece of wood looks to still have marks from
the mill on it. How far through the grits did you take it to prepare the surface? Maybe Yeah, yeah, yeah isn't the best way to encourage help. You're asking and we're answering.

lukeallison
16th January 2017, 05:16 PM
I didn't sand it at all as it's "dressed". I figured it was pre sanded.

LGS
16th January 2017, 05:31 PM
Well, that's probably half your problem. There are valleys and mountains on a "dressed" piece of timber. Before you start on the next one, try sanding it down to about 240-400. You might find that you'll get the result you want.

Regards,

Rob

lukeallison
16th January 2017, 05:42 PM
Is there a reason to use 240-400 and not lower? Valleys and mountains as in a non-straight surface? I thought these would be milled to a nearly perfectly flat surface.

LGS
16th January 2017, 05:52 PM
The timber is run through a thicknesser, but it depends on what thicknesser you are using, the quality and purpose of the timber. Why would you make Tas Oak for example, flat as possible for making fence posts?
What's the problem with sanding to 240? It's the minimum most people would sand to. Do you want to do any work on this or have it all done for you? You could try another timber yard, one that sells furniture grade timber and see if that's flat enough for your purpose, but I'd still sand to at least 240 and probably to 400. It will
give a superior finish

lukeallison
16th January 2017, 06:04 PM
Sorry, I meant higher. Why not go 600, 800, 1200? Is there a point of diminishing returns at 400?

LGS
16th January 2017, 06:35 PM
There's not really a law of diminishing returns, but for your first application, you could go something like, 100, 240, 400. and that will probably give you what you want. Higher grits can be used but they are more in play when you are going to apply an oil and then sand it in to the wood. Or in other cases where a high gloss may be desired. In this case, you'd sand to 400 and apply the oil, then sand the oil into the wood. This gives a good base for the application of the oil and then wipe on Poly, or another product. Have a look here (http://damnfinefurniture.net) and click on Hard Burnishing Pictures. This is just one of a multitude of finishing techniques, but the thing I want you to understand is that you can take a rough piece of timber and sand it to make it reflect flat timber sanded to 4000 grit. Try using 240 and 400 grit and see how you get on.

lukeallison
16th January 2017, 06:44 PM
Will wet (oil) sanding pull the stain out of the wood? Otherwise it looks like an awesome technique to get a uniform finish with the oil.

LGS
16th January 2017, 07:00 PM
Keep a bit of the stained and dried wood and add the oil as proscribed. I think it works OK, but I've only ever used it on natural timbers. You might find that wipe on Poly will do the job for you.

Regards,

Rob

lukeallison
18th January 2017, 09:29 AM
Really starting to notice the vertical lines in the wood that runs perpendicular to the grain. Are these the milling lines? I'm sanding my heart out with 240 and it's slowly fading them. Was I supposed to start with something more coarse?

Alkahestic
18th January 2017, 11:24 AM
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
18th January 2017, 11:40 AM
I would even add 180 grit between 120 and 240 and use a random orbital sander if you have one

homey
18th January 2017, 10:31 PM
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
18th January 2017, 10:45 PM
Here's one of Bob Flexner's articles on wood prep:

Preparing Wood for a Finish @ The Finishing Store News (http://news.thefinishingstore.com/index.php/preparing-wood-for-a-finish/)

Brian

lukeallison
19th January 2017, 10:23 PM
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
20th January 2017, 02:46 AM
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
22nd January 2017, 09:58 AM
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
22nd January 2017, 10:40 AM
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
26th January 2017, 02:49 PM
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
26th January 2017, 10:02 PM
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
26th January 2017, 10:06 PM
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
26th January 2017, 10:19 PM
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