Spoke shaves and spar planes

[Audasea]

I have built a birdsmouth mast, and before finishing it would like to finish smoothing it up. To knock down the edges, I just used a #5 jack plane, followed by sanding. I attached a picture of it, and it is finished much smoother than this, but it still has a few high spots.

Normally, you hear about using spoke shaves like a Stanley 51 or 151 for this use, but those have flat sides. In reading up on those, they appear to function exactly like a plane, with a shorter bed. Useful for smoothing the flat side of a curved board, but no better than plane for rounding edges of a mast or spar. There are smaller concave spokeshaves, but those all have 2 inch or less radius, so they might be useful for table chair spokes, oars, etc. but not something that is larger, such as a mast. The mast in the picture is 2 1/2 inches, so it wouldn't fit in the throat of the shave.

Bob Smalser shows how to build a spar plane...

http://www.woodenboatvb.com/vbulletin/upload/showthread.php?t=9360

But that is beyond my resources (no woodie.....no table saw, no grinder).

Some card scrapers have some radius to them, but again, the concave curvature is too small to fit a larger mast. Any other suggestions?

[Audasea]

PS: How to you get decent sized, viewable pictures to post inside the message?

[JBreeze]

Picture:

http://i185.photobucket.com/albums/x92/jbreeze_albums/thPicture120.jpg

Would something like this help? Dynamite Payson uses a sanding belt, turned inside out to shape shafts.....go to step 8

http://www.instantboats.com/images/oars8150.jpg

http://www.instantboats.com/oarmaking.htm

(Note: I don't know how to get decent sized pictures, especially from other sources, so no comment from me!)

[Jay Greer]

The trick is to first facet off the sides evenly, using a jointer plane. In the case of most spars a jack plane has too short of a bed. If the spar is an eight sided bird's mouth, I use a home made marking gauge that will put pencil marks down the length, dividing it into sixteen sides and plane them down to sixteen evenly between the marks. Once this is done, I use a wood bodied jointer plane that is modified so as to have a concave bottom. The blade is ground so the edges die into the mouth of the plane, allowing only a fine shaving to come off rounding the spar further. This is important because it avoids planing hollows in the mast. Then I follow up with a flat bed air sander known as an air file. It has a 14" bed and the grits start at sixty and progessively work up to 120. The shoe shine method of sanding used by some builders, in my opinion, can create unfair areas.
Jay

[Audasea]

This mast was 12 sided and had small edges to knock down. I do have a #6 Stanley that I could have used.

Jay....are you talking about one of those older styled long board wooden planes you see in antique shops? Perhaps it could be modified as Bob did his little woody....if I had a table saw. I'd also have to modify the blade, and I'm not sure I'm up to that either.

[Jay Greer]

This mast was 12 sided and had small edges to knock down. I do have a #6 Stanley that I could have used.

Jay....are you talking about one of those older styled long board wooden planes you see in antique shops? Perhaps it could be modified as Bob did his little woody....if I had a table saw. I'd also have to modify the blade, and I'm not sure I'm up to that either.

Yes, that is exactly what I am speaking of. But on a mast as small as yours, a smaller plane will work. Usually a savable wood bodied plane can be purchased for under thirty dollars. A table saw is the easiest tool to use for modifying the sole of the plane. Lay out both ends and make a series of cuts at different heights. This can also be done with a router and fence, carefully. A carving gouge will also work for rough smoothing the cuts. Then finish, using a scraper ground to the curve. Final finish can be done with sand paper on a shaped block.
Grinding the blade to match the sole can be accomplished by first coating the blade with layout blue, setting the blade in the body and
Scribing the curve. Grind on a shaped wheel and finish with slip stones.
Jay

[Bob Smalser]

For one or two spars already in progress, I wouldn't go to the trouble of making a spar plane.

You can make a round using bench planes alone with very little sanding. When you finish your 16 sides and are about to split the corners into 32 sides, adjust the plane iron upward on scrap to remove about half of what it removed to go from 8 to 16 sides. You may have to change planes to a smoother if your jack or jointer can't be set that fine.

Then switch to an even finer set going from 32 to 64 sides, going to an adjustable-mouth block plane if you have to. Then finish with paper.

You readjust the plane iron upwards for a finer cut as you go to remove the danger of bringing the corner down past the circle tangent. And the less that needs to come off and the finer the cut, the shorter the plane can be.

[alkorn]

Once you get it down to 16-sided with a flat pane you can finish it fairly quickly with a sanding belt. I don't know about the powered arrangement Dynamite Payson used, but if you cut a 40- or 60-grit belt and just go at it by hand, shoe-shine fashion, you can make rapid progress. Physically, it's a bit of a workout. If you don't want circumferential scratches you'll need to do the final sanding with ordinary sandpaper and lengthwise strokes.

[BrianY]

Bob -

I'm having trouble understanding what you mean when you refer to "half the amount" - are you talking about the thickness of the shavings or the width?
If it's the width, I assume that the plane blade should have a slightly rounded edge - not straight across, right? Not right???

[Bob Smalser]

Both actually, but I was speaking about reducing the depth of cut or shaving thickness.

Keep the same depth of cut for 16 sides when trying for 32, and you'll plane to 16 sides until you run out of wood, because you are planing past the circle tangent.

All spar planes do is speed up the process. You don't need a TS....you can make one with a hand saw and gouge, but even with a TS making one will take longer than finishing your spars without one.

Y'all's choice of course, but I'm not a big fan of sanding across the grain by hand, let alone with power. It just makes more work removing scratches. I prefer to go from the final whispy shaving to one light pass with 150 grit by hand directly to the paint brush. With a spar plane on a solid spar, I don't sand at all. Birdsmouths usually require sanding because the grain often changes direction between strips, making them more difficult to plane cleanly.

[Jay Greer]

The spar shop at Carl Chapman Boat Works was where I first went to work as a teen ager. And, it was where I learned to build, shape and sand spars the right way; other wise I would have been given the choice of going back to pushing broom or leaving. I chose to build and sand the way the boss wanted it done and stayed until I was able to open my own boat shop.

As bob mentioned, shaped sole planes make the job a bit faster. This is especially true when working on long, large diameter spars. My mind just flashed back to the single day I spent making mine some forty years ago. The time spent is of no consequence now and the time saved by them over the years is legion.
I adjust mine so that just a floating gossamer shaving of wood is removed. The blade should never be set so deep as to allow the corners to protrude.
When rough sanding a spar, after final planing, I often use a sanding board with 36 grit paper. This allows me to roll the sanding tool a bit as it moves fore and aft. I do prefer my air file. They are available at Harbor Freight for about forty bucks. It makes sanding a breeze and fairing a snap! Every shop should have air. At no time do I resort to the shoe shine method of sanding.
Jay

[Audasea]

The 8 16 32 64 sided method with straight bladed planes sounds the easiest. Even if I did overhaul a woody to a shaped sole, I'd have the problem of sharpening the blade as easy and as well as I can flat ones. I'm not doing this for a living! BTW, that mast is 12 sided (so it would be 12-24-48), with the 30/60 degree cuts made with a birdsmouth router bit from Veritas. Very easy to do.

I do think a regular card scraper with about a 5 or 6 inch radius on one side would work at the end as a possible substitute for the sand paper. Except as Bob mentions, on a birds mouth mast, the grain may run in different directions. Sandpaper is the solution for that.

One complication for all this is the fact that the mast was glued up with thickened epoxy, which oozes out and even if you wipe it down between the clamps, is still going to be present. Whatever plane is used is going to have to bust through that in the beginning. Tough on blades you care about.

[Jim Ledger]

Don't overthink it.

32...64..who's kidding who?:rolleyes:

[Jay Greer]

Cabinet (card)scrapers do not work well on soft wood as they have a tendancy to tear rather than cut.
Jay

[Bob Smalser]

32...64..who's kidding who?:rolleyes:

Rest assured after a comment like that, you're gonna get to see exactly that next time I do it. ;)

Just another task your tailed tools won't do without ear plugs, sanding dust, and usually lotsa ugly patches less than fair when you sight down the spar.

[boatbear]

I use an ordinary Stanley #4 to get to the point where it is hard to tell how many facets, and then cut a new 120 grit sanding belt (100mm wide) into two pieces to finish sand, working along the grain. Sanding belts are nice and stiff and cut pretty quickly. With two hands cupping the belt you've got the perfect tool.

Run your hand lightly along the mast at this stage. Human fingertips are very sensitive to surface irregularities.
Charlie

[Jim Ledger]

Rest assured after a comment like that, you're gonna get to see exactly that next time I do it. ;)

Just another task your tailed tools won't do without ear plugs, sanding dust, and usually lotsa ugly patches less than fair when you sight down the spar.

Still flogging that same old horse, eh?:rolleyes:

Go on then Bob,, show me something I can't do.:D

Don't make us wait. You know I wouldn't.

[Jay Greer]

Gentlemen, we are flogging this post to death!
Jay

[botebum]

Gentlemen, we are flogging this post to death!
Jay

I disagree. Obviously there are many ways to achieve the end product and it's good to see them all presented. That said, we could do without the infighting:rolleyes:

Doug

[Paul Scheuer]

One more lash -

I'm thoroughly in the shoe-shine-sanding camp, with a few additional tricks.

1. No rounding until the polygon is complete.

2. Before knocking off the corners, make sure that existing flats are flat, smooth and even.

3. Make the layout for the edges of the new flats as accurately as possible. (no sketching)

4. I treasure my old belt sander "blow outs". To do the job right they have to be limber, even if the're missing some of their original grit.

5. After the faceting, a center line on each flat is the key.

6. The shoe-shine sanding is done with a full 180 degree contact, i.e. vertical pulls. You will see that the center line doesn't get sanded durng the removal of the corners.

7. Although I move along the workpiece, with diagonal strokes, once the center line starts to smear, I dont go back.

8. The final, axial sanding is just enough to prepare for the finish.

My best effort, so far, is a maple kayak paddle with 90 degree offset blades with perpendicular oval grips, with the loom making a smooth transition from oval to round to oval. I've been asked how did I do that on a lathe.