RO125 Ipe' fun (almost)

[rjfarel]

I am making some Adirondack chairs from ipe' and wanted to see how far I could go on abrasive grit and still see a noticeable difference on this extremely dense wood.

Well, I guess one could say I went "all the way".  I took my abranet sampler pack (80 - 600) and had at it.  With each successive grit, the ipe' got noticeably smoother and smoother.  After the 600 grit the unfinished surface almost felt like granite and I was somewhat sad I didn't have anything finer.  Then I remembered the Platin 2000 pad that came with the Rotex.  Woohoo!  Did that thing make that ipe' shine!

So now I have this ipe' armrest that is incredibly smooth to the touch.  It's a raw wood that feels like a solid material without the coldness of granite or corian. 

I bring the armrest into the house to impress the wifey.  She's impressed.  I leave the thing inside for a couple of days so I can show a coworker.  Two days later, I begin to notice surface checking on the smoothed side.  The rough side (only knocked down with 80 grit) had no checking at all. 

I am curious as to why the smoothed side would do this.  I understand ipe' is a unique type of wood and thinking that in sanding to such smooth finish then polishing it with the Platin 2000, I might have actually melted the cellulose of the surface fibers on the surface.  The hardened surface cellulose then would not have the elasticity required to withstand the movement of the wood below.

Do other hard woods do this?

Thoughts?

- Bob Farrell

 

[nickao]

Sanding like that on one side of the wood is like putting a finish on one side of the wood. I have had this problem in the past on many different wood.

When you brought the wood in and it acclimated to the new room conditions all the moisture either released or was let in, through one side of the wood because the other side you effectively closed off.

I have seen this in many woods not just hard woods. Put some shellac on one side of a piece and throw it in the shop and more than likely it will curl, crack or cup. Sand the piece again, add shellac to both sides and a lot of times it will start to flatten out.

This is one reason to let your wood acclimate to room conditions as long as possible before working with it. Excessive sanding and/or finish on one side can effect the wood tremendously especially if the wood has excessive moisture, is not acclimated long enough or the piece is just moved to a different environment.

Of course their are many more reasons this can happen, but it is not a characteristic of just Ipe.

 

[rjfarel]

Thanks.  That's just the kind of information I was looking for.

 

[CharlesWilson]

When both sides are finished identically, if one side is more open than the other to the atmosphere (such as outside vs inside of a box) it will react faster, and the wood will tend to curl temporarily. This is very noticeable in one of my smaller projects that uses 3/8" thick hardwood throughout.

Charles

 

[minimal]

Remember to use dust collection (and possibly a mask!) when doing a lot of ipe sanding! The dust
of this wood are supposed to be particularly bad for you.

 

[rjfarel]

Ipe' dust is one of the worst types of dust out there.

You need good dust collection.  You need a respirator.  You need to clean up well afterwards (and wear the respirator while you clean).