To sand or not to sand?

[ELM6061]

G'day all, long time lurker crawling out of a borers hole.

I have recently started doing some volunteer furniture repairs, for a local charity op-shop, so they can on sell the furniture.
Now I am no woodworker, certainly no training apart from tech school 36 years ago, so just a bit of a hack really. Fixing chair & table legs, the odd set of draws etc etc, I am ok at. However the old antique stuff I am not sure about. The did have someone who was very good at this type of work, but they are no longer available and I am the only fix it man apart from a volunteer electrician.

At present they have an old crystal cabinet which the varnish/shellac finish is lifting from (quite badly) around the top mostly, and they want me to repair it. My advise was to just leave it, so the purchase-e had the choice to either have it professionally done, or do it themselves (I also have a dickie shoulder, so any excuse will do if it gets me out of sanding). Anyway, no, they want me to do the best I can and so here I am looking for some advise.

What is the best way to repair this type of thing;
Can I use some form of paint stripper to minimise sanding?

If I do sand, I know to follow the grain; But how when there is a thin skirt around the edge? So you do not damage/misshape it's ridge lines?

Do I have to do it all, or can I just spot repair?

Do we risk d-valuing the item, should it be left to the pro's?

Any "help" or advise will be greatly appreciated.

Eddie

[burraboy]

If it is shellac, find out by rubbing with metho first. Then use turps to see if you get any reaction. Both of these are much cheaper than paint stripper if you can get away with them. Use fine steel wool if you need to. Sanding is a no-no. It is sometimes possible to just repair the damaged areas without doing the lot, keeping an area evenly finished is the trick to a good look. That has worked for me anyway.

[Robson Valley]

Sandpapers scratch the surface to ever diminishing depths. It is still a scratched up surface. OTOH, coarse steel wood cut off the bits that stick up without scratching (if you go easy).
Case: I had no choice but to use Douglas-fir chair railing molding to make a match for the profiles. Now, D. fir (Pseudotsuga menziesii) has a spiral thickening in the S2 layer of the secondary, wood cell wall. As soon as you paint or stain, the cut cells stand up quicker than the teeth on a rasp. You will never, ever get a smooth surface with sandpapers = crude. 3-4 light passes with coarse steel wool and smooth as glass.
I would have not believed it if I did not have to prepare 50m of that crap chair rail.

[burraboy]

D. fir (Pseudotsuga menziesii) has a spiral thickening in the S2 layer of the secondary, wood cell wall.

That's right, I was just about to say that.
[D. fir = Dogwood. (D is fir dog)]

[ian]

Hi Eddie
can you post a photo or two ?

the problem might be the finish, which if the piece is old enough might be fixable with a little metho (make sure it's true metho and none of that 5% water rubbish) steel wool and fresh shellac
on the other hand it might be lifting veneer, which is another set of problems

[Horsecroft88]

Now I am going to have to disagree with the comments made re the use of sandpaper. Quite honestly I have been restoring antiques, and antique joinery both for myself as well as semi professionally as needed. Most antiques that I have restored, and especially joinery has been painted. To restore these I always hand strip using a heat gun. Thereafter I use paint stripper to clean off the residual with coarse grade steel wool. Then I always sand, grades used include 120, 240-260 and thereafter 400, and from my experience I can readily acieve a mirror finish, French polishing the timber. I always build the finish in stages of 3-5 coats, with light buffing back beyween stages with 400 grade sand paper. The more stages, the greater depth of finish and final luster achieved. The final polish is always with ultra fine 0000 grade steel wool and bees wax polish. It's not hard to achieve but is labour intensive. However the finish always speaks itself. So much has been written about not using sandpaper, however, it has its place. The point really is how it is used. Likewise I have seen much said re using metho and steel wool to remove old shellac, it's works but is slow, paint stripper is actually more efficient, however always neutralize afterwards, before re-coating the new finish.

[rustynail]

Now I am going to have to disagree with the comments made re the use of sandpaper. Quite honestly I have been restoring antiques, and antique joinery both for myself as well as semi professionally as needed. Most antiques that I have restored, and especially joinery has been painted. To restore these I always hand strip using a heat gun. Thereafter I use paint stripper to clean off the residual with coarse grade steel wool. Then I always sand, grades used include 120, 240-260 and thereafter 400, and from my experience I can readily acieve a mirror finish, French polishing the timber. I always build the finish in stages of 3-5 coats, with light buffing back beyween stages with 400 grade sand paper. The more stages, the greater depth of finish and final luster achieved. The final polish is always with ultra fine 0000 grade steel wool and bees wax polish. It's not hard to achieve but is labour intensive. However the finish always speaks itself. So much has been written about not using sandpaper, however, it has its place. The point really is how it is used. Likewise I have seen much said re using metho and steel wool to remove old shellac, it's works but is slow, paint stripper is actually more efficient, however always neutralize afterwards, before re-coating the new finish.

As apprentices, if we were caught using steel wool we would have got our butts kicked!

[mic-d]

As apprentices, if we were caught using steel wool we would have got our butts kicked!

Why was that? It shouldn't be used on bare wood but to rub a finish in the final stages is acceptable.

A photo or two would be handy Eddie.

[Lawry01]

Now I am going to have to disagree with the comments made re the use of sandpaper. Quite honestly I have been restoring antiques, and antique joinery both for myself as well as semi professionally as needed. Most antiques that I have restored, and especially joinery has been painted. To restore these I always hand strip using a heat gun. Thereafter I use paint stripper to clean off the residual with coarse grade steel wool. Then I always sand, grades used include 120, 240-260 and thereafter 400, and from my experience I can readily acieve a mirror finish, French polishing the timber. I always build the finish in stages of 3-5 coats, with light buffing back beyween stages with 400 grade sand paper. The more stages, the greater depth of finish and final luster achieved. The final polish is always with ultra fine 0000 grade steel wool and bees wax polish. It's not hard to achieve but is labour intensive. However the finish always speaks itself. So much has been written about not using sandpaper, however, it has its place. The point really is how it is used. Likewise I have seen much said re using metho and steel wool to remove old shellac, it's works but is slow, paint stripper is actually more efficient, however always neutralize afterwards, before re-coating the new finish.

Have to agree with HC here...have a look at the (very long) thread I started a few months ago https://www.woodworkforums.com/f173/g...please-151803/ Whilst theres a lot of banter in this, I must say that the lessons learned from HC & WW particularly might be of value fo your project. Have a coffee, then a look!

lawry.
ps Dave..good to see you on here..how are you travelling?

[Horsecroft88]

Hi Lawry, thanks for the post and support, thanks I am ok now. Friday was hard, saying goodbye to a good friend is never easy, but 600 odd people came, which shows how well he was liked by so many. (a good friend of mine passed away tragically - took his own life). Will post some more info on my resto project progress shortly on my thread topic.

Sorry all for the off-thread conversation.

Firstly, and importantly, any comments I am making re use of sandpaper, steel wool, paint stripper, shellac etc are simply mine, based on my experience. I am not for a second trying to say it is the only way, or that you even have to agree with me. We each have our experience base to draw upon.

To the topic of use of steel wool in woodworking and especially in context to finishes. Let me say I understand partly where Rustynail is coming from but yes in my view Mic-d is on the money.

Coarse grade steel wool, in my view is the perfect material to remove paint scum, in conjunction with paint stripper say after heat -gunning off old paint, be it on old furniture or joinery. I would even go as far to say it is similarly useful for removing old shellac in conjunction with metho. The point being with the latter, that what you are removing is an old surface that previously would have been appropriately finished off ie. sanded and then sealed by the shellac that had been applied. The issue as I understand it is the concern of steel wool particles to get embedded in the wood grain and therefore risk of rust forming.

However, this is really only a risk in my view if you are talking about using coase grade steel wool on a new wood surface that hasn't even been sanded, as we are talking about timber with grain, which can catch the steel wool particles. Using steel wool in such a case is not appropriate, that afterall is what sandpaper is for, (to cut the bare wood surface back) to a surface ready for applying a finish (seal). Similarly, I wouldn't advocate using steel wool between coats, as sandpaper is the right medium to be using, albeit with finer grade papers than the original sanding.

Fine grade steel wool however, is the perfect medium to be using before the final bees wax polishing stage, and that is because whether you have used a shellac finish or some other finish, the wood grain is sealed and the purpose of the steelwool is merely to cut the finish back to take the wax polish. It is kind of similar to the use of 2000 grade wet and dry paper when cutting back a painted surface (ie. cars), before buffing with polish.


Now I know that some people disagree with the use of sandpaper, especially in relation to restoring antiques. Obviously the issue here is two fold (a) the risk of damaging edges, and surfaces from over sanding or bad sanding and (b) the issue of damaging the patina of a piece of furniture. I understand both concerns, and so hence my point re this is the how you use sandpaper. I would even go as far to say that at times, the best technique is essentially to do nothing, but merely clean the surface, perhaps a 0000 steel wooling and re-application of wax.

The choices one makes needs to be appropriate to the piece of furniture you are working with, and the condition of the surface finish, and/or any damage to the surface (ie. scratching, heat/water marks, or timber damage etc). All techniques can and do have a place in my view. I hope that clarifies any concerns people might have.

Now back to the thread topic re Eddie's project. A photo might help clear up the issue and suggestions to help you.

[rustynail]

I realise that steel wool does an excellent job as a between coat abrasive but it is very sacrificial in its nature. Just the process of moulding the wool to the shape of your fingers or the shape of the piece to be sanded causes fibre brake up. When the fibres do break, they form a sharp edge which has no difficulty impregnating itself into a soft polish. When looked at through a strong magnifying glass this is quite frightening. But then again, just about everything looks pretty frightening through a magnifying glass. The problem is, when steel wool is used under wax, eventually the wax wears back exposing these microscopic steel particles which then rust. Rust grows, so what was once unnoticiable to the naked eye now becomes a blemished surface. Some polishing formulars have corrosives in their chemistry which means these tiny fragments of steel can be attacked even though they are subsurface, forming blisters in the polish.

[Horsecroft88]

Ahm, actually no, in my view steel wool should never be used as an abrasive medium between coats, and/or especially at the start of the process of "sanding" the surface of wood, that is fresh and never been coated with anything.

I do know of people who have used steel wool for this between coats process but it is not something I am advocating, afterall that is what sandpaper was invented for.

The point in using 0000 grade (ultra fine) steel wool at the final stage is that because it is so fine, and because you only should use this prior to bees wax polishing, you run no risk of steel wool fibres becoming entraped in the wood surface, (that is my experience), albeit I have never looked at such wooden surfaces under a strong magnifying glass. I rely on the feel I get from running my hands/fingers over the surface to tell me all I need to know. In all the years I have been french polishing antiques/antique joinery as per methods described above I have never seen any signs of rust forming. For one thing the use of bees wax polish should prevent moisture getting in due to the barrier it creates, even if there was to be residual particles remaining.

And besides, given the quality of nails and screws used in furniture/joinery construction in the past, you are more likely to get rust (localised staining) around said nail or screw, but that never worries me, since for me that too is a part of the patina, just as much as an ink stain, burn mark, dent, scratch etc.

As for blemishes such as blisters in the final polish, well all I can say is I have never had such a problem occur. Maybe others have experienced differently from me.

[rustynail]

Fair enough, if you havent experienced the problem you are perfectly correct in persueing the methods you have found satisfactory. This does not alter the fact you would have got your butt kicked.
The sad thing about all this is everone has a different cut off point for steel wool use. Some still persist with fine sanding of bare timber, insisting they have no problems. Others use it between coats, while others say it should only be used prior to wax. May I suggest, the problems I have mentioned are rearly instantaneous, but instead, become manifest over time. Beeswax is capable of covering a multitude of sins and steel wool fragments are but one. Problem is, beeswax doesnt last for ever. Fine steel wool is just as capable of fragmentation as courser wool. Rust is not particular about gauge. For mine, the risk is great enough to obstain.

[Horsecroft88]

I can live with what you note Rusty. All is good. I think in a way this is one of the really good things with forums such as this and a couple of other ones I am on, you can learn so much from other people's experiences.

It is always good to keep an open mind, and look for alternative solutions, or seek others advice to help in your own projects. Cheers Dave

[rustynail]

Sorry, meant to write abstain. Wasn't trying to be obstinate.
Cheers Ken.