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I'm making a desk for my son using hard birdseye maple as the material for the top. I've never worked with birdseye specifically before, but I've used hard maple in other projects.

The top is 32" x 54". I glued it up using 3/4" S3S boards sized using a ripping blade for my table saw and biscuits. It wasn't perfectly flat, but good enough, so I started in on sanding. I have a Makita 9403 4" x 24" handheld belt sander, and I sanded the top with new 80, 120, 150, and 240 grit belts. I sanded pretty much with the grain, but I rotated the sander a little as I was moving along as birdseye is flatsawn and can have quite a bit of wavy grain, depending on the piece. I put pencil lines across the piece between each grit as a way to verify that I was sanding it evenly and thoroughly.

As I was progressing through the grits, I noticed a little bit of waviness – ridges in the texture of the surface. They weren't sharp, like I'd left the sander running for too long in one spot and the edge of the belt had dug in, but fairly smooth, like a series of gentle hills and valleys. What was interesting was that they didn't necessarily follow features of the grain. For example, when sanding soft "SPF" woods like yellow pine, the darker growth rings are more dense than the lighter wood in between, and if you're not careful you can get ring texturing in the surface when sanding. My ridges are not like that – they follow the direction of the grain, but cross individual grain lines without changing.

I'd like to rescue this if I can before I start the finishing process. Unfortunately, I don't have access to a wide belt sander (if you know of any in the Boston, MA area, please let me know!), so I'll have to stick with what I have available, which is the Makita belt sander, a DeWalt 5" random orbit sander, a decent low-angle block plane, and a lousy knockoff bench plane. With such highly-figured wood, the thought of planing doesn't make me very happy, so I'll have to figure it out with sanding.

Would sanding against the grain with 240 and then with it again have any effect, or will it just create unnecessary scratches? What about cross-grain with a rougher grit, then smoothing again? I'd like to ultimately go up to 320 or 400, then perhaps (or instead) do a few passes with a good cabinet scraper to really "pop" the figure before finishing. Would the scraper be the best option for flattening the top as well?

Any and all suggestions are welcome.

FreeMan
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MattDMo
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  • Try the RO sander at 120; go down if need be, then up. A belt sander is a great tool to ruin a flat top. – Aloysius Defenestrate Jun 26 '22 at 21:48
  • Panel is now slightly less than 3/4" thick yes? – Volfram K Jun 27 '22 at 05:24
  • Ironic the glue-up ended up not flat as this is basically what biscuits are for in panel work! Sans wide-belt sander, and assuming hand planing is not an option, a belt sander is arguably one of the best ways to go about flattening a large panel. But it's tricky to do well freehand and all too easy to inadvertently introduce some irregularity that's difficult to recover from. I presume you've lost some thickness already and would prefer to minimise the loss of any more so I don't know what to suggest other than scraping, as per the other Q&A which I know you've already seen. – Graphus Jun 27 '22 at 15:57
  • "Would sanding against the grain with 240 and then with it again have any effect, or will it just create unnecessary scratches?" Sanding cross-grain is supposed to be one of the key tricks to helping achieve a flat surface with a belt sander (working both diagonals IIRC) before then sanding with the grain. 240 is likely too fine to really be effective though, but of course you didn't start out with the thickest material so the usual advice may not really apply "I'm currently thinking of using Odie's Oil for the finish." Have you bought it already? If not, many better options (all cheaper). – Graphus Jun 27 '22 at 16:03
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    @AloysiusDefenestrate, the run-of-the-mill ROS can maintain a flat surface quite well if not used carelessly but they're pretty terrible for making surfaces flat because they're so poor at precisely targetting high points while not affecting adjacent areas. – Graphus Jun 27 '22 at 16:14
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    I took out the bit about the choice of finish, as that's a totally different question. – FreeMan Jun 27 '22 at 16:31
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    @VolframK somewhat thinner, but not so bad that I'm worried about structural integrity or something like that. I would have preferred to start with a 1" top, but I don't own a planer/thicknesser and the place I get my wood only had surfaced birdseye in 3/4". – MattDMo Jun 27 '22 at 16:52
  • @Graphus (1) the lack of flatness after glue-up was probably more due to overzealous clamping than anything else. The biscuits did help align the boards quite well. I'll try the scraping today. I was practicing prepping the scrapers over the weekend (well, amongst other things...) so I can get a good "hook" on them. – MattDMo Jun 27 '22 at 16:55
  • @Graphus (2) If you have any tips on better belt sanding technique, I'd love to see an answer from you. Like I mentioned in the question, I rotated the belt sander a little when I was sanding, but didn't make any conscious effort to go cross-grain for large swaths, which is what I think you're talking about. Any knowledge and experience you'd be willing to share would be great. Re: Odie's Oil - I've used BLO and various "varnishes" (polyurethane, shellac, marine spar varnish, etc.) for years, but only recently came across Odie's and thought I'd give it a try. I like my test piece so far... :) – MattDMo Jun 27 '22 at 17:04
  • @FreeMan no worries. I added it mostly as an afterthought, as the main question is definitely about sanding. I was surprised, as I just searched the site and there's no mention of odie's or odie, so perhaps I will ask a finishing question, too. – MattDMo Jun 27 '22 at 17:07
  • @graphus — agree that a ROS is bad for flattening. My notion was that the ROS could be useful to knock down some of the ridges after being bitten by the belt sander. – Aloysius Defenestrate Jun 27 '22 at 17:39
  • "so perhaps I will ask a finishing question" That's perfect, this is precisely how related or follow-on Questions to an original query should be handled (although in practice, here, we see it surprisingly rarely). – Graphus Jun 27 '22 at 21:42
  • "I like my test piece so far... :)" OK so you have it already and you like the test, now the critical thing — check it against other things you have, see how it compares in all the ways that matter (not just looks). If you have multiple varnishes on the shelf, thin down a spoon or two of each and wipe them on, blend the poly with BLO, thin it a little (this is homemade Danish Oil / Tung Oil Finish) and try that too. Be sure to check waterproofing and* scratch resistance*, because a lot of people don't do both (some don't do either!) which makes for some v questionable recommendations! – Graphus Jun 27 '22 at 21:46
  • yes absolutely and fair enough. We do not have that wood here more did I ever worked with it. Will keep watching this post to see how you proceeding. theoretically the scraping makes sense, however I would imagine it also can leave bad marks on greatly figured wood. – Guido Coza Jun 27 '22 at 21:12
  • I know I throw a spanner in the works, however, did u ever consider hand planer? If done with the right one, u really just take out the tops and 1/10 mm at the time. after that u would need to sand again though as u would have two distinct finishes. Did something similar on a blackwood countertop on the weekend and it came out with a mirror finish – Guido Coza Jun 27 '22 at 18:28

1 Answers1

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At first I tried planing (using test pieces instead of the actual top), with both a pretty well-tuned low-angle block plane

Stanley low angle block plane

and a cheap Buck Bros. #5 jack plane with a freshly-sharpened blade,

Buck Bros #5 jack plane

but I haven't had time to tune anything else. The low-angle worked better than the #5, but I had tearout issues with both of them, so I didn't let them near the actual desk top.

I then tried using a card scraper. Once I got a good burnished edge curl on it and figured out how to hold it properly it gave me very good control at removing wood just where I wanted to. However, with the amount of wood it removes with each pass (a very thin shaving, or just dust) and the amount of surface I had to flatten (32" x 54" – 813 mm x 1372 mm), plus a bit of arthritis in my hands, it would have been a daunting task to scrape flat the entire surface.

Then I happened across a Kunz-manufactured version of the #80 scraper plane:

Kunz #80 scraper plane

It differs from a card scraper in several ways – the blade is about twice as thick, approximately 1/16" (0.06" or 1.53 mm), the curl is burnished from a 45° angled edge instead of a flat 90° one, the depth of cut can be adjusted somewhat by raising and lowering the blade in the housing, and importantly (for me, at least) the tool is comfortable to use for long periods of time. It requires the same amount of force pushing away from your body, but the wear and tear on your fingers from forcing the card scraper into a curve is completely eliminated, as the blade is curved by means of a screw in the middle of the body.

Even with an aggressive cut depth, it still took me at least 2-3 hours to get the entire surface to a more-or-less flattened state. After the initial scraping, I drew pencil lines over the surface and used a random orbit sander with 120 grit sandpaper to get an even finish and find any remaining high/low spots. I came back with the scraper to address them, and after a couple rounds it's looking pretty good!

MattDMo
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  • Well since nobody else has upvoted your Answer I guess I'll be the first! Quick thing on terminology/naming, I thought I remembered you saying you had a cabinet scraper in the Q, although there is some variation on this 'cabinet scraper' is often (mostly?) what the tools like the no. 80 are called, while just the rectangles of steel are simply card scrapers. And scraper plane is more used, at least these days, to describe actual planes with wooden body similar to a coffin smoother, or metal body with handles, with an upright scraper blade (sometimes adjustable for angle). – Graphus Jul 09 '22 at 06:56
  • Re. tearout with the no. 5, how close were you able to set the cap iron in relation to the cutting edge without the shavings becoming jammed? – Graphus Jul 09 '22 at 06:57
  • @Graphus (1) thanks for the clarification on terminology. I may have mentioned "cabinet scraper" in one of my comments, but I meant a card scraper. I used "scraper plane" to describe the #80 because that's what the Amazon page I linked to used. – MattDMo Jul 09 '22 at 13:56
  • @Graphus (2) I set the cap iron as close as I could to the edge while still leaving a little bit of blade showing. I played around a little with blade depth (how far below the bottom of the plane it protruded), but not frog or cap iron position. I only did a little fiddling with it because in the middle of it I found the #80, and decided that was a much better option for me, based on several articles I've read and videos I've seen. And it worked, so I don't have any complaints! I'll keep playing with the #5 as I have time, as I'd like it to be a functional part of my tool arsenal. – MattDMo Jul 09 '22 at 14:01
  • Yes what works works for sure! And cabinet scrapers are a very important tool for sure, once you have one you'll probably make a point of using it more because of how well they work. Do be sure to persevere with your no. 5 though as it's a super-versatile and capable tool, capable of being in effect a long-sole smoothing plane or a large scrub plane (a roughing jack), or both if you have two blades for it :-) – Graphus Jul 10 '22 at 06:43