Casein problems

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Parson

Parson

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Joined
Jun 10, 2009
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798
Location
Houston, Texas
Folks, I need some input for some warranty work I must do for a good customer. This casein top has seen no abuse whatsoever. Yet it looks terribly scratched up now, just a month or two after I made it.

I cannot remember if I coated it with CA glue or not.

Has anyone else had this problem before? If so, what's the cause and how do I avoid it in the future?

The material's really expensive so I don't want to see this happen again :(
 

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Hmm..that is weird. I wonder how the scratches got on it? I am waiting for some answers too. Never seen that before.
 
That's got vertical and radial marks like something's been rubbed against it fairly hard. Can't tell by the picture if it's scratches or marrings with either way... Is it being kept in some kind of a case that has hard surface/
 
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Actually the owner swears he's not been rough with it. The scratches seem to be from my sanding... But they weren't there when I finished the pen. Puzzling.
 
They also appear to be sanding marks to me. Are they below the finish? I am not familiar w/ the material so I cant help you there.
 
Parson said:
Folks, I need some input for some warranty work I must do for a good customer. This casein top has seen no abuse whatsoever. Yet it looks terribly scratched up now, just a month or two after I made it.

I cannot remember if I coated it with CA glue or not.

Has anyone else had this problem before? If so, what's the cause and how do I avoid it in the future?
Eie
The material's really expensive so I don't want to see this happen again :(
Click to expand...

Casein, allthough nice looking, is not the best material for making a durable pen...my opion and others will disagree. There are too many other excellent materials to use inferior ones. Alternative casein may be a better choice.
Do a god turn daily!
Don
Sent from my SPH-D700 using Forum Runner
 
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Randall.
I have seen this before. I had something similar happen before I learned that Casein should never be touched with dry sandpaper or a pen mill.

My THEORY is that rough sanding marks became microscopic and seem to disappear when polishing. Since Casein is a "living, breathing protein", I think that scratches widen and deepen over time. I OFFER NO PROOF.

BUT, since I tossed the pen mill and never touch Casein with anything more abrasive that WET 600 grit abrasives, I've had no other issues.
 
It looks like sanding marks to my eyes, also. In fact, it looks like there might be 'with the grain' sanding marks also. I suspect that they were there the entire time, but weren't super ugly until the pen got some use and got 'dirty'.

Dissassemble it and resand to a nice finish. It's quite likely that the blank will then be 'over turned' so build up a nice CA finish to make up for the lost material.
 
sbell111 said:
It looks like sanding marks to my eyes, also. In fact, it looks like there might be 'with the grain' sanding marks also. I suspect that they were there the entire time, but weren't super ugly until the pen got some use and got 'dirty'.

Dissassemble it and resand to a nice finish. It's quite likely that the blank will then be 'over turned' so build up a nice CA finish to make up for the lost material.
Click to expand...

I respctfully disagree.

If this is what I think it is (sanding marks that turned to hairline cracks), additional sanding will cause even worse future problems, in the exact same spot.

I've made literally hundreds of Casein pens, and under NO circumstances would I ever again use a CA finish. Casein needs to breath. CA almost assures cracks will develop.
 
I am tending to agree with Steve and Andy on this. What if you had microscopic scratches on the pen at the very beginning. Oil, dirt and other stuff could build up within these crevices and cause the discoloration. I had this experience with a pure white alumilite cast I needed. It had tiny air pockets which filled up with sandings and other "stuff". How fine did you sand the top--MM, buffer ????
 
Take a 17x jeweler's loupe and examine the marks carefully. If they have any "depth" it will confirm if the scratches became hairline cracks.

The pen in the photo appears to have a CA finish over it and the discoloration could easily be a reaction between the protein in the Casein and the acid in the CA.

Even though Casein is relatively expensive, I'd make the good customer a new pen.
 
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Thanks for all this excellent advice. I disassembled it and tore it up in the process. So I turned him a new cap out of casein with uber-sharp tools and no sandpaper... Just MM pads and water. Sined up real nice.

I think I coated it with CA and those scratches were all mine. Now I know better.
 
This is interesting. I've made one casien pen so far and haven't seen any problems with the pen yet, although it's only a couple months old and not yet sold, so it doesn't have any use.

I believe mine was polished similar to Andys recommendations although I don't start we-sanding until the 3'rd pad in the MM pack. It *do* go very lightly on the coarser grits, usually starting with 320 or 400 and each being used vertically and radially to reduce scratches. So I guess time will tell for mine. And I did NOT use any CA on it, so maybe that will help as well.

Are there any recommended polishes that you can use on Casein?
 
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