Myths & Mysteries

[woodbrains]

Hello,

Everything is a compromise and at some point you have to weigh up whether switching to abrasive is going to be an expedient worth taking to save a bit of faffing. At some point we almost all do, but it is at what point we do it that matters. it is perfectly possible never to use planes and finish everything with abrasives. This has been proven to be extremely time consuming and gives an inferior finish to a planed surface. I suppose the abrasives used could be taken to the nth degree of fineness to improve the finish further, but that would take even more time. Law of diminishing returns here. There is no doubt that a planed finish gives a fine, burnished surface which will take oil, wax, shellac, polyurathane, cellulose laquer etc without any grain raising issues. Any fine nibs here are just dried micro-bubbles set on the surface as air raises out through pores in the wood. This would happen on a sanded surface too. Waterborne finishes and dyes will raise the grain of a planed or sanded finish.

Logically, if we hone our plane irons to 1 micron abrasive or there abouts, how could an abrasive used on wood which is much coarser, give a better result? Sanding wood with abrasives, down to a few microns, would likely be so time consuming as to be an absurdity.

You would be surprised how many do actually use hanplanes down to a finish, using abrasives for those elusive bits of tearout, but perhaps 90% remaining hand worked. Look at the furniture from the College of the Redwoods if you want to see minimal sanding on finished pieces. Whether this is economically viable for professionals is debatable, but many CR graduates become professionals. And after all, the many who contribute here do not want to have to deal with professional pressures; we want to enjoy our work in dust free and relatively quiet environments.

Mike.

 

[Jacob]

Hello,

Everything is a compromise and at some point you have to weigh up whether switching to abrasive is going to be an expedient worth taking to save a bit of faffing. At some point we almost all do, but it is at what point we do it that matters. it is perfectly possible never to use planes and finish everything with abrasives. This has been proven to be extremely time consuming and gives an inferior finish to a planed surface.

Quite the opposite. You give up on planing and take to abrasives precisely because it is quicker, usually because you just want to get the damn thing finished! And of course the finish is superior - so much so that heavily sanded work looks over-finished, too perfect, artificial, no longer hand made.

 

[David C]

Richard,

Totally agree. These wierd fetishes arise from time to time in the amateur field.

best wishes,
David

 

[Corneel]

Weird fetish or not, and yes I'm just an amateur. But why would I want to sand after I have made a very nice surface with a handplane?
What does sanding do to improve the surface? Remember, I'm not into staining or other complex things. Oil and wax are my favorite finishes.

(not trying to be smart this time, just asking a question).

 

[Jacob]

Weird fetish or not, and yes I'm just an amateur. But why would I want to sand after I have made a very nice surface with a handplane?
What does sanding do to improve the surface? Remember, I'm not into staining or other complex things. Oil and wax are my favorite finishes.

(not trying to be smart this time, just asking a question).

Agree. It's only if you have to. Sometimes getting a good finish with a plane is difficult. That's why it's a major theme of these forums - alternative theories without end!
If it wasn't (sometimes/often) difficult it wouldn't be an issue and people wouldn't use scrapers, sandpaper, ROSs etc. These aren't amateur fetishes.
If anything the perfect plane finish has become an amateur fetish, the impossible dream. along with a lot of other tooly issues.

PS Sellers is into sharp planes, close cap irons etc in line with theories which abound here. He's also into scrapers as the ultimate fine finisher (they don't scrape they cut, etc)

 

[Corneel]

Well, maybe because the amateur has the time to perfect his planing technique. Then it's not realy a fetish, just the desire to get better at something. When you grab the ROS each time the planing is a bit difficult, you won't make any progress.

But I'm not allergic to sandpaper. Use it quite often in fact.

 

[Jacob]

I'm going to spend more time with my scraper!

 

[David C]

There are good reasons for sanding. If the finish is one which will need sanding between coats, any scallops or ridges left by the plane will cause variations in the thickness of film. It may in fact be cut through on high points. This leaves a very disapointing streakiness in the final result.

Flatness is needed and the simplest way to get this is with some fine sanding. I might use 240, 320, 400grit.

David

 

[Corneel]

Aha, that's a good reason. Thanks.


Well, luckily I like an oil finish a lot on most types of wood I work with. Saves me a bunch of work.

 

[Jacob]

Best of all possible worlds - plane as far as you can, belt sander followed by ROS working through the grits, finish with scrapers! Obvious innit? Perhaps not.

 

[Trafalgar]

I was told when at school (45yrs ago) that the reasons that beech is used is that it is stable, reasonably damage resistant (hard) and above all that there is very little spring in it, so there is no "give" when chopping huge mortices etc..
With very few people doing work of any weight (in that sense), what the bench is made of is probably of less importance now.

While not strictly traditional, it seems logical to me to make a benchtop out of a species softer than the the species of the furniture parts worked on its surface. IMO, a three inch thick (+) lamination even of the softest species ought to provide more than enough mass except under the most unusual of circumstances.

 

[devonwoody]

And a welcome to the uk forum, Tennessee sounds musical.

 

[Sgian Dubh]

Everything is a compromise and at some point you have to weigh up whether switching to abrasive is going to be an expedient worth taking to save a bit of faffing.

Mike, I'm certainly not advocating that planes should be abandoned altogether during wood prep, and that the whole job should be undertaken with abrasives. I realise you don't think I believe that.

I've found that, in hand-crafted furniture anyway, a surface is most swiftly got almost or near polish ready with well set up planes, scrapers and the like. There comes a point where sanding is necessary, even when the metal edge cutting tools have done a great job, just for the sake of speed if nothing else. How much sanding depends on the job, and the type of subsequent finish. A film forming polish over oak only needs a final sand at about 180 grit-- the open pores of the wood are coarser than the grit size at about that point. A film forming polish over a fine textured wood such as sycamore or cherry need only be sanded to perhaps 220 or 240 grit. So after planing and scraping it's common to at 120, 150, and for coarse timbers 180 grit as a final grade, and with 220 or 240 grit for fine grained timbers. Any finer generally doesn't help as the striations are hidden under the layer of polish. You might sand a bit finer for wiped on finishes such as linseed oil, pure tung oil and waxes.

That sort of prepping regime fits reasonably well into the College of the Redwoods philosophy you mentioned.

However, I stick to my earlier point where I stated that I've never seen a piece of high quality commercial woodwork or similar top quality professionally made furniture item of any sort go out of the door and into the client's possession that wasn't sanded in some form prior to applying polish, no matter how well the surfaces were hand planed before finishing started.

I've seen plenty of completed woodwork delivered to the client with a finish applied straight over the scallops left behind by power planers and spindle moulders, etc, but that was for a different type of client of a different type of product. Slainte.

 

[Corneel]

The question remains, why? What does the sanding accomplish that the plane didn't? I understand from David's answer the reason to sand before applying a film finish. But with an oil or wax finish?

You will see or feel when watching carefully the scallops of the smooth plane of course. I wouldn't call that detracting at all.

 

[woodbloke]

Everything is a compromise and at some point you have to weigh up whether switching to abrasive is going to be an expedient worth taking to save a bit of faffing.

Mike, I'm certainly not advocating that planes should be abandoned altogether during wood prep, and that the whole job should be undertaken with abrasives. I realise you don't think I believe that.

I've found that, in hand-crafted furniture anyway, a surface is most swiftly got almost or near polish ready with well set up planes, scrapers and the like. There comes a point where sanding is necessary, even when the metal edge cutting tools have done a great job, just for the sake of speed if nothing else. How much sanding depends on the job, and the type of subsequent finish. A film forming polish over oak only needs a final sand at about 180 grit-- the open pores of the wood are coarser than the grit size at about that point. A film forming polish over a fine textured wood such as sycamore or cherry need only be sanded to perhaps 220 or 240 grit. So after planing and scraping it's common to at 120, 150, and for coarse timbers 180 grit as a final grade, and with 220 or 240 grit for fine grained timbers. Any finer generally doesn't help as the striations are hidden under the layer of polish. You might sand a bit finer for wiped on finishes such as linseed oil, pure tung oil and waxes.

That sort of prepping regime fits reasonably well into the College of the Redwoods philosophy you mentioned.

However, I stick to my earlier point where I stated that I've never seen a piece of high quality commercial woodwork or similar top quality professionally made furniture item of any sort go out of the door and into the client's possession that wasn't sanded in some form prior to applying polish, no matter how well the surfaces were hand planed before finishing started.

+1...spot on Richard. I'm currently making some picture frames from English Walnut and after cleaning up with a very finely set BU smoother, a quick going over with some 240g is all that's needed. Wipe the edges with a bit of worn stuff and they're ready for their first coat of oil...sorted - Rob

 

[Sawyer]

Planing vs sanding - it's 'horses for courses' surely? Depends on the nature of the job, costing, time allowed, species of timber, period detail (where applicable), intended finish, and many other variables.

When cleaning up machined components to remove the ripple marks, I find that usually, a well set plane is much quicker than abrasives. Whether that planed surface then needs further work with scrapers or abrasives depends on the variables.

Personally, I like to see some subtle traces of genuine hand work, but whether that's appropriate depends, again, on the variables. If I need to sand, I sand, if I don't - then I don't bother.

In answer to a point above, I have delivered plenty of 'for profit' jobs unsanded for a variety of reasons. Recently an oak table which following the attentions of various planes, finishing with a 4.1/2, came out so well that it needed no further work. This was exceptional however and it is rarely that easy. Had I thought that abrasives were needed, I would not have hesitated...

 

[Corneel]

Yes that sounds reasonable. Sand when neccessary because you're not happy enough with the planing results. Not sand always as a matter of course.

Recently I've finished my kitchen project. I even borrowed a ROS for that one, because I couldn't get the surfaces smooth enough.

 

[Sawyer]

For me, sanding is an option, not a foregone conclusion. I love my planes, but would not be without my belt sander, either.

 

[custard]

But what about when the finish itself depends on sanding?

If the finish needs any sanding then you can only really apply that finish over a previously sanded surface, otherwise when you sand the finish you'll cut through on the microscopic ridges that planing or scraping always leave.

 

[János]

Hello,

Abrasives work on exactly the same principles as hand planes, the difference is limited: a hand plane have one, wide cutting edge with a predetermined cutting geometry, the abrasives (sanding paper, sanding stones etc.) have multiple, very small cutting edges with varied cutting geometry. But the underlying physical laws and principles are much the same. The edges of the individual abrasive particles have different cutting angles, cutting widths, and cutting depths, but that is all: they work like a bunch of miniature planes in unison. Just because you do not see the curls of shavings you are so familiar with, and do not fully understand what the heck is going on, do not blame the tools.

Most of the representative, large scale works of the "krenovites" have found their homes in galleries and museums, where they will never see any proper use. Contrary to all myths, oiled and waxed furniture surfaces are the most sensitive to damage or abuse, and need very-very good preparatory work. To put oil or wax to a "plane fresh" surface of a non-decorative furniture item (eg. a dining table, chair, children's toys etc.), that is silly thing... I am a professional cabinetmaker, I hand plane my work. But I care about the days after delivery...

Have a nice day,

János