Badly behaving Mahogany solutions requested

[Aaron Rosenthal]

I have a few pieces of Mahogany; It was sold to me as such, for a larger project and not this remaining part is my 12% overage. I know there's a lot of things they call mahogany, but I'm not sure what exactly it is. I can say that hand planing the width is a pain.
I'm getting incredible tear-out along what I'll call the softer "ribbons" as I'm planing the length of the board.
Sharpened and honed (green oxide) a No. 6 bevel down; re-did my No. 3 same problem. Yes the cap iron is less than 1 mm from the blade.
Went at it with a newly sharpened and honed L.V. bevel up smoother, with wispy shavings from the "harder" ribbon, and tear-out on the softer area beside it.
I admit, I normally attack Oak and Maple, so this one is strange to me, but I'm actually wondering if hand planing is the wrong way to do this; perhaps " just run it through the planer, and sand it.
Oh, yes, my card scraper technique is terrible, but I did try a freshly set up and burnished scraper but I'm not happy with the result either.

[Warren Lake]

Photo? we are not Kreskin, sounds like quarter sawn sapele, the ribbons go opposite directions never had trouble with it, machine it then sand it on the stroke, takes stain and finish excellent.

[Andrew Hughes]

African mahogany is horrible to handplane. It’s also unstable. Sapele might even be worse the sapele I see at the wood mongers is 95% quarter sawn. That alone tells me it’s horrible to dry and sawn for this reason. Rowed wood kiln dried is no bueno with handplanes.
Accept only Genuine Mahogany and avoid substitutes

[Mel Fulks]

Sounds like African “mahogany “ I have proved to the chagrin of a couple of bosses that it isn’t mahogany. Make a snake out of AM and
after seeing it’s moved while you were at work and you will shoot it !

[Warren Lake]

okay just to be clear i never had trouble to plane it then stroke sand it for finishing.'

As far as how it behaved it did not tension release like any material ive ever used. I figured a machine issue and first time ever set that machine up coplaner to almost bang on. the material was totally the same so I knew it was the material and not the machine. Positive though first time ever that machine was trued up to a level that was more than enough and had never been measured past as always machined fine. As i machined it and expected it to move like any material it did pretty much the opposite. It finished really well as i was matching past stuff they had.

customer sample on the right


484037

[Aaron Rosenthal]

I do have some African “mahogany” I actually brought with me when we moved back to Canada. It’s not that. Warren, it looks just like your picture on the left.
The place I got it from is well known I’m the area and goes to a lot of trouble to be particular about naming it properly.
Like Warren’s samples, when the original job was finished, it looked just as good as his beautiful figure and colour.
It’s just now that I’m trying to work it by hand I’m coming up with the issue.
I’ll post pictures tomorrow

[Mel Fulks]

I remember , years ago reading that African ‘mahogany’ was often referred to as “ribbon mahogany”. When REAL mahogany was “discovered”
by Europeans the main thing they noticed and loved was how easy it was to work.

[Warren Lake]

An old guy once told me there were over 300 types of mahogany but i think more accurate would have been 300 types of including lots that are wannabees. I had to step down to African after Honduras for years and it stunk in comparison. i hand pick and get the best but it was just not close. It didnt have the colour or work the same and it just was not as pretty.

When machined I saw the fine tear out of the opposing rows The tear out to me didnt matter as it wasnt much off high speed steel planer knives. I have a stroke sander and it cleaned up easily. Machines likely did better with it than your hand planes. It might be you need to use a circular motion with your hand plane, ive seen old guys who plane that way most of the time. Have you tried different angles going into it 45 degree or. Derek and other hand plane guys will help you more with that. I have them just go for machines first.

[Mel Fulks]

There are only two kinds of real mahogany . Swetinia macrophyla and Swetinia mahogani . The latter is the heavy dense one found first and
quickly used up. Dragnet type coda : The Facts are Real….Only the spelling is made up….. too late at night to bother with spelling !

[Kevin Jenness]

Aaron, pictures would definitely help. You may have a weird batch of ribbon striped Swietania Macrophylla but it is not something I have run into. Your description sounds more like Khaya or possibly Sapele.

Warren's photos look like Sapele to me, but he can say for sure. I would set aside the hand plane for machining/sanding, but you might try setting the cap iron closer yet (.010") and grinding it more obtuse for a lower rake angle. If you post your query on the Neanderthal subforum you will get a plethora of advice.

You could send a sample to the Forest Products Lab for ID.

[John TenEyck]

I just had some plain Jane looking mahogany tear out on my drum sander, hard as that is to believe. No idea what species it is, but it's not African nor Sapele. The only way I could get it smooth was to drum sand it on the diagonal, and that only worked in one direction.

Warren's picture looks like Sapele to me, and I've never had much trouble with tear out. I plane it and then drum sand, however, to avoid that problem, and only use hand planes to bring joints flush, etc.

John

[Warren Lake]

quarter sawn sapelle. The terms tear out dont mean much as there are different levels. Both those ribbons are going in opposite directions so they shear off different, one is smooth and one is more open if that is a way to describe it. There are no chunks torn out just one smoother than the other. Stroke makes easy work of it.

[Tom Trees]

" Yes the cap iron is less than 1 mm from the blade..."

So you understand that this is a two plane process.
You have honed your cap iron at least 50 degrees on both cap irons on those planes.
You understand a tight mouth will STOP the cap iron from being able to be close enough, so you're doing this on both planes with the frog set back/OPEN mouth.
(Yes, I know one can work on the "wear" of the plane, but that would be for other reasons, nothing to do with learning how the cap iron has influence and tearout elimination)

Your work is either plonked on the bench sitting flat, or it's rigid enough not to deflect.
You have enough clearance of the bevel... i.e, no contact of the heel and the work, should the primary bevel be too steep and need grinding again to trad angle.

Should be getting straight shavings, burnished waxy and crinkly, if not then no cap iron influence is evident, and you need to set it closer,
@50 degrees on the workhorse plane, will be set no further away than 1/32", exactly that is about the very max for productivity, and if even tougher examples are present, it might need to go somewhere in between that, and 1/64" (you'll know how much your panel/fine jack/try plane should be set, once you use a smoother set no further away than 1/64" from the edge, so you may have too much camber.

Some might hone the cap iron steeper instead, as that is relative to how close it can be set to the edge.

All the best
Tom

[John TenEyck]

Some great information in that short post Tom. I had to read it twice to fully understand it. Thanks very much.

John

[Tom Trees]

No bother John

Two other tips which may well be relevant for someone in bother.
Fettling the underside of the cap iron.
if one cannot remove a belly, and the cap iron rocks about when stacked on the cutter/blade...

Then a little square/strip of abrasive, narrower than the width of the cap iron, say a half to three quarters, will get rid of that, and just a rub or two afterwards on the whole surface
will prepare it nicely, (making sure there is a good undercut)

A great tip from David W, if having trouble with getting the camber perfectly even. (which it needs to be)
This is actually noticeable now more than ever, as there is no room for any adjustment with cap set so close.

Instead of leaning or tipping with fingers very very close to the edge, actually place a finger on the very edge getting finger dirty on the stone!
Where your finger is placed on the iron, will pin point the "target" (as David's "targeted removal" phase goes)
much like splaying fingers when sharpening a card scraper, and evident polish where fingers were.
This makes it easy to get the camber absolutely perfect.:)

For a long time I was wasting material and taking ages to get the shape right, before David's passing comment.
It's the only way I can do it without trouble, and I've tried a lot of various methods through the years.
Doesn't sound like it makes a difference, but it does, so another cheers for David!

Tom