Wet sanding problem

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Gabericks

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Oct 12, 2019
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South Carolina
Hey wise pros. I'm finding that when I wet sand a CA finish with Micromesh I'm getting water under the finish and it ruins the finish on the ends. Has anyone had this problem and any advise to deal with it? Thanks!
20201013_082120.jpg
 
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Dehn0045

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Mar 19, 2017
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Looks to me like the finish is sanded through on the end, not uncommon to happen at the ends.

I personally don't think a little moisture on the ends is usually a problem, but I have had some problems with deer antler that I believe were related to moisture from wet sanding. I have put CA on wax paper and wicked CA on the ends prior to applying CA to the blank. Also have applied CA to the ends using open cell foam. But honestly I'm not sure there is a ton of value to this. I think there may be some added risk to cracking the ends if all of the voids are completely filled. Also, be sure to clean out any excess CA from the inside of the tube or you'll definitely have a cracking problem.
 

jttheclockman

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Feb 22, 2005
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NJ, USA.
Have to agree with others that this looks like a case of sand through. Now I will also agree that CA on the ends is vital if wet sanding and I do as mentioned, put some thin CA on wax paper and wick the ends and wipe off excess before sanding wet. Why take a chance when not needed.
 

MRDucks2

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Jul 17, 2017
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Bristow, IN
The consistency of the band of damaged material is why sand though is being mentioned. Moisture damage is most often less consistent. John's point is most valid if it does look more like moisture in your hand than in the photo. Seal the ends.
 

leehljp

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Feb 6, 2005
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Tunica, Mississippi,
If moisture was the problem, 95% of the time, the CA would be cloudy in near the end.

That pict shows sand-through. I don't know your method of finish, but quite often, too often, people do not get as thick of a build up of CA as they think. It is NOT the number of layers that matter, it is the THICKNESS of the layers that are important to prevent sand-through. I do have experience and many here also have experience - I "can" add more thickness in two layers than some people put on in 8 - 10 layers. I rarely put more than 3 of my layers on and do not have sand-through. It is a matter of thickness build up.

Calipers help determine how much build up is there. Don't measure the diameter of the wood by the bushing. Measure with the calipers.
 

egnald

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Jun 9, 2017
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Location
Columbus, Nebraska, USA
Greetings from Nebraska!

From my past experience I agree with all of the others - this definitely looks like a sand through.
I have had this problem before as well as water infiltration on the ends. My current regimen seems to have mitigated both of these problems however. To be brief:

1) After Turning, sand the wood to 800 grit while still mounted.
2) Remove bushings and replace with HDPE No-Stick bushings
3) Apply Finish using the HDPE No-Stick bushings (very thin and very even coats).
4) Remove and using 1200 grit sandpaper, carefully remove the CA buildup "fingernails" on the ends.
5) Apply thin CA to a paper towel blotter and touch the ends to the blotter to seal the ends
Sometimes I do this twice to make sure the ends are sealed well.
6) Replace on the mandrel using the turning bushings.
7) Wet sand with all of the MicroMesh grits.

Note: I apply my CA in very thin coats to make sure it goes on very evenly to minimize the amount of sanding with MicroMesh. Typically I only spend no more than 10-15 seconds per grit per blank. Using the standard bushings during this process helps prevent rounding or sanding through on the ends.

Hope this helps.

Regards,
Dave
 
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