What doesn't stick to PR.

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chartle

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Going to make some molds and need to know what PR doesn't stick to.

I'm going to use some cutting board scraps, probably uhmw polyethylene, for the main mold but does PR stick to the outside of painters tape, the good 3M stuff?
 
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mecompco

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I'm getting ready to make my first molds and I'm wondering the same thing. I do have a 3/4" UHMW poly rod that I made some non-stick bushings from (which didn't really work that well). I also thought about turning a 3/4" poly blank round and using that. Thoughts?

Regards,
Michael
 

BSea

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As far as painters tape, I use it on the bottom of bottle stopper molds (PVC). The PR will stick a little, but not a lot. Now that's the sticky side, not the outside. But even if it sticks, it will be on the outside of the blank, and will turn off, or sand off.

You can use PVC tubes for vertical casts, but the tubes get sticky after multiple uses. I've made molds using cutting board material, but that was for alumilite. I know you can get the tupperware type molds at walmart. I think Wood-n-Whimseys sels them also.

If you intend to do a lot of casts in a flat mold, If really think about using PtownSubbie's molds.
 

chartle

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As far as painters tape, I use it on the bottom of bottle stopper molds (PVC). The PR will stick a little, but not a lot. Now that's the sticky side, not the outside. But even if it sticks, it will be on the outside of the blank, and will turn off, or sand off.

You can use PVC tubes for vertical casts, but the tubes get sticky after multiple uses. I've made molds using cutting board material, but that was for alumilite. I know you can get the tupperware type molds at walmart. I think Wood-n-Whimseys sels them also.

If you intend to do a lot of casts in a flat mold, If really think about using PtownSubbie's molds.

I'm using a 3 inch 8 mm tubes so those molds wouldn't work but thats the style I would be making.
 

BSea

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As far as painters tape, I use it on the bottom of bottle stopper molds (PVC). The PR will stick a little, but not a lot. Now that's the sticky side, not the outside. But even if it sticks, it will be on the outside of the blank, and will turn off, or sand off.

You can use PVC tubes for vertical casts, but the tubes get sticky after multiple uses. I've made molds using cutting board material, but that was for alumilite. I know you can get the tupperware type molds at walmart. I think Wood-n-Whimseys sels them also.

If you intend to do a lot of casts in a flat mold, If really think about using PtownSubbie's molds.

I'm using a 3 inch 8 mm tubes so those molds wouldn't work but thats the style I would be making.
Before you say they won't work, I'd contact Fred. Even though a mold may be designed for a particular tube, it doesn't mean it won't work for something else. For example, I think the cigar mold will make a sierra blank. He also has some molds that aren't on his site. I've bought a mold from him that wasn't on his site. It never hurts to ask.
 

chartle

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As far as painters tape, I use it on the bottom of bottle stopper molds (PVC). The PR will stick a little, but not a lot. Now that's the sticky side, not the outside. But even if it sticks, it will be on the outside of the blank, and will turn off, or sand off.

You can use PVC tubes for vertical casts, but the tubes get sticky after multiple uses. I've made molds using cutting board material, but that was for alumilite. I know you can get the tupperware type molds at walmart. I think Wood-n-Whimseys sels them also.

If you intend to do a lot of casts in a flat mold, If really think about using PtownSubbie's molds.

I'm using a 3 inch 8 mm tubes so those molds wouldn't work but thats the style I would be making.
Before you say they won't work, I'd contact Fred. Even though a mold may be designed for a particular tube, it doesn't mean it won't work for something else. For example, I think the cigar mold will make a sierra blank. He also has some molds that aren't on his site. I've bought a mold from him that wasn't on his site. It never hurts to ask.

Thanks for the info but right now this is a one off experiment. Also I don't sell my pens so I May just make one or two.
 

79spitfire

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Sounds like the way to go is PVC. You can get some plugs for the tubes and then rig them up to hold them centered. Cutting boards make great molds, but keep in mind PR can take a bit to cure, and it will find any gaps in the seams and seep out. You can likely use anything for a mold, you may just have to spray a bit of mold release on it.

In my experience, Alumilite is much stickier than PR and it really does stick to pretty much everything, except silicone...
 

chartle

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Sounds like the way to go is PVC. You can get some plugs for the tubes and then rig them up to hold them centered. Cutting boards make great molds, but keep in mind PR can take a bit to cure, and it will find any gaps in the seams and seep out. You can likely use anything for a mold, you may just have to spray a bit of mold release on it.

In my experience, Alumilite is much stickier than PR and it really does stick to pretty much everything, except silicone...

The issue is I need to see if there are any bubbles and a horizontal mold will let me spin and inspect the blank.

What I'm casting is fine cord so its going to be a bubble catcher. I may spend 5 or 6 hours of meticulous hand work on this blank before I cast it, I can't afford bubbles. My plan is to tack the cord down with CA and then apply a few coats while spinning it on the lathe before casting to seal it.
 

79spitfire

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The molds from PTownSubbie seem like what you need then. He can supply molds with the stoppers going through the silicone so you can spin the tubes inside easily. He's a nice guy, you can contact him with special needs as well.
 

chartle

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The molds from PTownSubbie seem like what you need then. He can supply molds with the stoppers going through the silicone so you can spin the tubes inside easily. He's a nice guy, you can contact him with special needs as well.

Yes that was posted above.

I've seen his molds used but I may only be making a few pens if any so keeping costs low. I have the cutting board stock already and I can have or can make the stoppers with tape for for now.
 
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