Crappy remains after finishing

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Amihai

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Oct 8, 2021
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Hello,
Tried to turn a pen from Holly. (As part of a set for a wedding, the second pen will be turned from Gabon Ebony).

Instead of getting a whitish pen, I got all of this bluish / greyish mud over the wood. I suspect that those spots are the remains of my blue shop towels.

Never had this problem before. What could cause the shop towels to leave such remains on the wood? Is there a way to fix the pen? Thanks!
 

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maxwell_smart007

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It looks grey to me - so it could be iron filings from sanding too close to the mandrel. You're noticing it because holly is bone-white.

But if it's bluish as you say, then perhaps it is your shop towels. Are you using BLO? what viscosity of CA are you using?
 

hooked

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Are you sanding while the blank is on the bushings? Holly is extremely light in color and easily picks up any metal dust from the bushings. It appears to me to be darkest right where the bushing meets the wood.
 

Amihai

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It looks grey to me - so it could be iron filings from sanding too close to the mandrel. You're noticing it because holly is bone-white.

But if it's bluish as you say, then perhaps it is your shop towels. Are you using BLO? what viscosity of CA are you using?
I do 2 layers of thin CA, continued by another 6 layers of medium CA. Not sure what BLO means.
 

Amihai

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Are you sanding while the blank is on the bushings? Holly is extremely light in color and easily picks up any metal dust from the bushings. It appears to me to be darkest right where the bushing meets the wood.
Yea I sand with the metal bushings still on.
How should I sand instead? With non stick plastic bushings?
 

studioseven

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I also think that the culprit is the bushings. If you don't have access to the non stick bushings you could easily just use wooden spacers. Drill a hole in a dowel that will fit your mandrel. Turn it so that it is smaller than your bushing. After you turn your blank, replace the metal bushings with the wooden spacers and then sand your blank.

Seven
 

howsitwork

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just a word of warning if you used pva to seal the log ends during drying you can sometime get this issue as well.

I think looking at it the contamination from the metal bushings is the most probable cause though.
 

jttheclockman

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It is contamination from the bushings. To fix the pen you would have to take apart. But if you have more of the holly I would start over instead of trying to build up CA. You do need to sand between center without metal bushings. I would stay away from wood bushings unless you are making them from holly. Woods of darker nature can contaminate white wood also thus my caution. You need to either make yourself some cone shaped nonstick bushings or buy some. they come in handy many times. Good investment.

My suggestion is to skip sanding and use the skew to turn to finished size and then right to CA.
 

leehljp

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Yea I sand with the metal bushings still on.
How should I sand instead? With non stick plastic bushings?
That is your problem. An absolute easy way which very few seem to grasp is to use a very sharp and just honed scraper at 3000 - 3500 rpm.

A few use a skew, but I cannot speak to that as I am not proficient with a skew.

I am not touting this pen which I did 12-13 years ago - but look at the metal, and particularly the dots. The dots are solder and smear like pencil lead - easy. Notice those dots, not a bit of smear, and they are much softer than the metal bushings, and smear much worse than bushings. Yet, I did not get any smear, just clean and clear cuts.



What I think most people do not grasp is that sandpaper (SP) smears and makes very very fine dust. Duh, we all know that, but SP creates dust and moves different colors (metal or wood) onto other wood. There is a simple way to stop that - I use a flat end scraper that has been rounded in the same manner as a radiused square carbide insert, only my scraper is an HSS. The scraper will scrape rather than sand, and all kinds of segmented woods and or metal stay as clean as they can be without the sanding dust. AND if one takes the time to do pristine sharpening, it will be as smooth as a baby's behind (an American colloquialism) with out the need for sanding.

Apologies for jumping to the main solution and bypassing a step: Plastic bushings will help, but the best way is without bushings and without a mandrel. TBC - Turning between Centers - Bushings are used between centers for most people to get it close to size, and then take the bushings off and place the blank directly between the Centers. then finish to size and finish. This method does allow for sanding if you want without getting sanding dust on the blank. . . . Still the scraper method works too. A few people use a skew instead of a scraper but lay the skew on its side on the tool rest and in effect use it like a scraper.
 
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MedWoodWorx

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It is contamination from the bushings. To fix the pen you would have to take apart. But if you have more of the holly I would start over instead of trying to build up CA. You do need to sand between center without metal bushings. I would stay away from wood bushings unless you are making them from holly. Woods of darker nature can contaminate white wood also thus my caution. You need to either make yourself some cone shaped nonstick bushings or buy some. they come in handy many times. Good investment.

My suggestion is to skip sanding and use the skew to turn to finished size and then right to CA.
i don't have a picture to show, but my wooden blanks seem to have similar marks. Do you guys believe its due to bushing or sandpaper contamination? Is there a possibility that my sandpaper is of low quality and leaves particles?cheers.
 

leehljp

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i don't have a picture to show, but my wooden blanks seem to have similar marks. Do you guys believe its due to bushing or sandpaper contamination? Is there a possibility that my sandpaper is of low quality and leaves particles?cheers.
Both and or combination. Mostly it happens with sandpaper moving over the bushings, then the sp grabs some of the bushing dust and brings it back over to the wood where it smears onto the wood and into the wood grain. But it can and does happen when the chisel/tool touches the bushing as the turner is bringing it to final size and then rubs some of the bushing dust onto the wood.
 

MedWoodWorx

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Both and or combination. Mostly it happens with sandpaper moving over the bushings, then the sp grabs some of the bushing dust and brings it back over to the wood where it smears onto the wood and into the wood grain. But it can and does happen when the chisel/tool touches the bushing as the turner is bringing it to final size and then rubs some of the bushing dust onto the wood.
I see. the thing is that i tried not to touch the bushings with the sandpaper but nevertheless i saw dust/dirt forming. I was using extra fine grits with walnut oil to saturate the blank before PP.
 

leehljp

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I see. the thing is that i tried not to touch the bushings with the sandpaper but nevertheless i saw dust/dirt forming. I was using extra fine grits with walnut oil to saturate the blank before PP.
It is quite common for this to happen. Some get proficient with handling the SP to the edge, a few get very good at removing the bushing sanding dust, some take the bushings off and replace with nylon type of bushings (can be home made) and then there is the taking the bushings OFF all together when finish sanding and adding a finish to it, also called TBC or Turning Between Centers. No bushings, therefore no sanding dust.
 

leehljp

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I have also to remove the pen mandrel right?
Yes, That is what TBC is. Much less problematic than mandrels. But there are "mandrel savers" for those who do not want to forgo the mandrel altogether. They use cone shaped bushings and measurements/sizings are done with calipers. With the cone shaped
"bushings", no sanding dust is there to contaminate the pen blanks.

Some people do OK with the PennStateInd mandrel saver. But several have had problems with it.
Woodpeckers.com and Whiteside make the best ones.
 
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