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My tabletop is made of selected SPF boards and has been planed with a handplane. I've added breadboard ends to each end. I'm preparing the surface for a finish, and trying to avoid sanding altogether, using a combination of planes and/or scrapers. I can obtain a sufficiently smooth and reflexive surface with just planing on individual boards of the same material.

I was hoping I'd be able to do a final pass with only a card scraper over the surface to remove irregularities, remaining visible glue, remaining pencil marks, and remaining little bits of tearout around knots, but my scraping makes the glassy surface I had from just planing look more dull -- i am losing some sheen.

I could maybe re-plane the entire surface one last time, but planing has been made difficult at this point with the addition of breadboard ends, orthogonal to the grain direction of the main panel. To a lesser degree, this is also true of the possible grain-direction reversal at the boundary of each board of the main panel (i.e. I don't think I considered grain direction when assembling my panel).

On softwoods (i.e. woods with low-density fiber), in practice, can card scrapers (once sharpened properly) be used to achieving a surface comparable in smoothness and reflection to that obtained by planing (i.e. well-tuned bench plane)? Can card scrapers achieve high gloss also on softwood endgrain?

Or should I just give up the blades, and sand it like it's 1999.

ww_init_js
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    This is a number of questions all together, try to limit yourself to one major query per Question so that Answers don't have to cover too much territory, and so that it's easier for future searchers to locate topic-specific info. The end-grain one near the end in particular would be better off on its own. – Graphus Dec 05 '17 at 08:15
  • I'm happy to dissect the question into multiple ones. Your (great) answers will have to be split, maybe. – ww_init_js Dec 06 '17 at 16:59
  • That was more of an FYI for future Questions. I think I covered all the necessary parts this time :-) – Graphus Dec 06 '17 at 18:31

1 Answers1

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my scraping makes the glassy surface I had from just planing look more dull -- i am losing some sheen.

No need to worry about that overly, one of the roles of finish is to add sheen and, depending somewhat on the finish chosen, it can equalise the appearance of different areas.

Although it is considered best if the wood has a uniform surface and appearance before finish application starts the grain direction can be all over the place (practically a given with SPF) and the wood will consequently absorb finish very variably regardless of how uniform it looked immediately before.

In areas of emerging grain, which are always seen somewhere around a knot, you'll have patches that will appear duller than the surrounding wood with the first one or two coats of finish because they are so absorbent. So it's often necessary to go to three or more coats to achieve a uniform sheen.

On softwoods (i.e. woods with low-density fiber), in practice, can card scrapers (once sharpened properly) be used to achieving a surface comparable in smoothness and reflection to that obtained by planing (i.e. well-tuned bench plane)?

Sometimes yes, often no.

Worth bearing in mind that many consider softwoods un-scrapable so you're in a minority doing it. I don't happen to agree as I refer to in this previous Answer but it's still challenging to get uniform results on softwoods, particularly where there are knots present.

As you might already know the problem with many softwoods is the softer earlywood (the paler stripes) is often extremely soft so it's very difficult to deal with, especially as the darker latewood is so much harder and won't wear away or scrape off at the same rate. This can lead to a sort of corduroy texture.

How far to take any surface is entirely down to the individual. Some people are OK with leaving traces of tearout because it's so difficult to completely remove, others don't want to see even a hint of it and will sand until it's gone, or take it to a certain point and then do a bit of filling to get rid of the last of it before the finish goes on.

Can card scrapers achieve high gloss also on softwood endgrain?

IME no. Others may have achieved different results but experimenting with all the different types and scraping strategies I've found you always have to do some sanding to make the end grain look as good as it can look.

Note: it's worth sanding end grain much more finely than the long-grain surfaces. I'd regularly sand to approximately the level of 320 when final sanding on the long-grain surfaces would be to 150, and some people with higher standards sand their end grain to 600 and occasionally beyond.

Graphus
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  • After gaining some experience with creating decent burr on card scrapers. Cardscraping seems necessary to remove plane marks (Generally those are visible either at the point where the plane blade started digging into the surface, or where it lifted from the surface and detached the shaving. -- Rarely do I plane entire lengths in a single glide of the plane).

    Also, many many passes of the scraper at a very low angle (so that very fine dust is produced instead of shavings) will restore some sheen, as long as the scraping is with the direction of grain. I will post some pics when I get to it.

     – ww_init_js Dec 29 '17 at 21:36
  • As far as the endgrain goes, sanding is necessary. I've never been able to produce plane shavings on pine end grain, despite the plane being razor sharp. My planes seem to bend the end grain fibers, pull them out, or cause breakout if I'm not careful. Card scraping on endgrain is hard, because I can't keep square, and I keep damaging the corners as I glide off. Sanding end grain, on construction grade pine will produce a very smooth surface, where even medullary rays can be seen, even with nothing finer than 100grit coarse Al2O3 glasspaper. – ww_init_js Dec 29 '17 at 21:45
  • Re. plane marks, or tracks, if you prepare your plane iron suitably they can become a thing of the past. A slight camber on the cutting edge or rounding off the corners are both intended to achieve this goal. It must be said though that finish-planing a surface, so that nothing at all is needed to be done to it before applying finish, is not a must-do and a great many full-time professionals don't do this (for the record it's because they can't, not because it's too much trouble for them). So there's no shame in reaching for the scrapers or sanding block to complete smoothing the wood. – Graphus Dec 30 '17 at 09:05