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I have found this really interesting site about wooden puzzles. It offers puzzle designers for free and from what I read

Anyone can reproduce these puzzles for his/her own personal enjoyment...

So, I'd like to make this burr puzzle with a scroll saw, but since I'm a newbie, I'd like to know from someone more skilled which kind of wood could be good for this kind of work and which finish guarantees a good user experience (e.g. pieces slide smoothly).

Thanks in advance

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which kind of wood could be good for this kind of work

If you have the choice you want a close-grained, hard wood for this sort of thing. Normally that will mean a hardwood, although yew (a softwood) would also fit the bill.

There are many decent possibilities depending on where you're located. Going over my memory of commercial puzzles I've seen in the past, numerous Asian-made ones I think used sheesham. More recently I think I've seen some made from rubber wood, which is neither as hard nor as close-grained but adequate nonetheless.

If you're in North America maple would probably be ideal, being easy to come by there and not particularly pricey. Some maples are softer than others, hard maple (sugar maple, rock maple) will be tougher as the name suggests, and although this makes it harder to work it may be worth it in the end product.

Beech would also be excellent if you can find it and birch might work as well. Although it's classed as open-grained I have seen 'executive' puzzles made from black walnut which indicate it can be suitable, and walnut is prized for it workability by woodworkers (being only a little harder than cherry).

which finish guarantees a good user experience (e.g. pieces slide smoothly).

I think you could get away with many things on something like this, including leaving the wood bare. I'm sure I've handled puzzles in the past which were bare wood.

Commercially I think most puzzles probably have a spray finish applied, which could be either varnish or lacquer. And with modern finishing moving away from high-VOC products it's likely that some are now finished with a waterbased finish or some kind.

My personal choice here would probably be a light coating of shellac, two or three thin coats brushed on. This would not be enough to build up much of a film on the surface but will partially seal it, enough that it won't easily get grubby from handling and slightly reduce any tendency for the pieces to expand/contract or warp with changes in humidity.


You haven't asked about shaping the pieces, but if high accuracy is important to the functioning of the completed puzzle then I'd give serious thought to cutting the internal notches by hand as though they were mortises. Or alternatively buying a suitable mortising bit for a drill and using it to do the same job.

If you do use a scroll saw you're surely going to need to smooth the sawn faces. For that I would highly recommend filing over sanding. If you don't have any files then glue abrasive paper to strips of hard wood so that it can be used in a similar manner to a file.

For sanding the external surfaces bring the wood to the paper and not the paper to the wood. Small pieces are nearly always best sanded this way, with the paper flat on the table (taped down taut or glued in place on a scrap board) and the pieces rubbed over it, rather than attempting to hold the workpiece in one hand and a sanding block in the other and rubbing them together!

You only need to sand up to between 180 and 220 grit.

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Scroll saws are inherently not that accurate, so I'd say it doesn't really matter what kind of wood you are using. (If you have the means to work accurately enough (0.1mm or less) you might want to use wood that does not warp and shrink/expand with temperature and humidity changes.)

In order to still get a satisfying result, it is a good idea to increase the size of the puzzle, in order to increase the relative accuracy. (Which is the key for nice burr puzzles. They should not be too tight such that you have to use force to move the pieces, but ideally they certainly should not rattle too much.)

I highly recommend first using some scrap/cheap wood, just to make a first "prototype" in order to gain some experience. The puzzle you linked to could easily be made from boards, so you could use a piece plywood. If possible, I'd still recommend cutting the outside of the pieces with a table saw to get a more accurate finish. I also suggest only sanding the pieces where absolutely necessary, as sanding usually results in less accurate and consistent pieces.

Finally I can recommend the forum on puzzle-place.com and reddit.com/r/mechanicalpuzzles for more information and inspiration.

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  • I know scroll saw is not that accurate for this kind of work but I hope to achive a decent result anyway. I'll surely follow your suggestions about plywood :) – c.bear Sep 15 '16 at 12:53
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Any tight-grained hardwood will work. Maple would be the obvious choice.

Cherry and Walnut are harder and also have better stability in general, if the wood is well prepared. More complex and more expensive than maple, but if handled well, will give a superior result.

The most advanced option would be hickory. Hickory is very hard and tough which makes it ideal for use in a small, delicate, precision puzzle. The problem is that it is difficult to work and has unpredictable dimensional behavior. I would not attempt hickory for this use unless I had a lot of experience doing woodcarving with it beforehand, not a material for beginners.

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A different kind of burr

Silly me. I assumed that you were setting out to make a six piece burr puzzle of the type made from six pieces of square cross-section wood - not conducive to construction using a scroll saw.

Scroll saw - the perfect choice

Upon rereading and actually connecting to your link, I responded with the thought, "perfect for a scroll saw!" or at least I thought, "the selection of scroll saw makes sense!"

If you have access to a table saw, the first step of making six boards 1 unit thick by five by seven units is the place to start. Carefully mark each board with its appropriate pattern and go to town. Make sure the gaps are wide enough to fit another piece through, ie a hair larger (not two hairs) than one unit. If the long cuts are not quite straight the puzzle should still work - just make sure that the openings are one unit plus a hair wide. If cut you the long openings a little too narrow, then sand or file them as needed. Also make sure that the corner cuts are square and not slightly rounded.

Use Baltic birch

For type of wood (your question) I would use Baltic birch plywood - it's uniformly thick, has not voids and does not splinter readily. I would use either 3/8" (9mm) of 1/2' (12 mm). For finish, either nothing or a quick coat of Danish oil. You might also want to very slightly chamfer all edges with sand paper.

Or do something entirely different

If I were making this puzzle, my first inclination would be to use square cross-section pieces of wood one unit by one unit. I would then cut the pieces of appropriate lengths (one unit, two units, three units, four units, and seven units) then glue them together. I know the gluing is going to be a bit tricky, but I would likely make some little jigs to hold the pieces in position while clamping.

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