Advice/thoughts needed

[Rob]

Today, I turned a dyed cobra skin set of blanks. They were not a home brew, I'm not smart enough to try that yet! They turned fairly easily and I began to finish them as I do all the plastics I've turned. I use wet MM and wipe the blanks down between grits up to 12000. I normally will complete the plastics with a small amount of Mother's Scratch Remover.

Under magnification, the blanks look flawless. There are no scratches, but they just won't take a "shine" as every other plastic blank I've turned. They almost seem to be a matt finish. I've gone over them a couple of times with the MM, but no change. It could be my imagination, but the blanks just don't seem as "hard" to the touch as others I've turned and I almost have convinced myself that they feel a bit "tacky" to the touch.

Has anyone else encountered this sort of situation with these plastics/acrylics? Could it be that the amount of hardener that should have been used in the batch is off a bit? I was reluctant to try it yet, but wondered if a couple of coats of CA would help. Of course I could end up with a shiny coat for a matt finish. Now that these have been turned down to size, will just leaving them alone harden them up?

I'd welcome any thoughts or suggestions. I really know nothing of the chemistry involved in these plastics. Perhaps there is no fix and I'll just have to work it out with the supplier. Thanks, Rob

 

[redfishsc]

My experiences with two-part cabinet finishes says you may be onto something. If the resin had a hardener, perhaps they used too little. I know that "conversion varnish" will not harden properly if it doesn't have 10% catalyst to it. Polyester resins, if they have a hardener, will likely not harden properly if the right amount of hardener isn't used.


My opinion is that you should contact the MFR with your complaint. If they do not assist you in some way, kindly inform them that you will take your business elsewhere.


You can try adding a CA finish, that may work. I'd sand the MM'ed blanks with some 400 grit paper first to give the CA something to stick to. It will hide the 400 grit scratches, I assure you!

 

[wdcav1952]

Rob, I seem to remember from a conversation with Old Griz that some cobra skin blanks he got from an Ebay seller were a bit soft and did not polish as well as others. FYI, the rattlesnake skin blanks that BB sells at ArizonaSilhouette.com work quite well.