Production casting - need help

[polarbear1]

I am in quite a predicament, hoping someone in the IAP community would have some suggestions. I have been casting personalized label pens for over a year with mixed results, almost exclusively cigar pens which seem to be one of the easiest to cast (due to the larger tube). About 4 months ago my oldest son asked me to make a pen for all the guest at his wedding (expecting about 70 guests) and I agreed to. He did not want the cigar pens, but wanted the designer/euro type pen. And I have been casting and turning the pens since, but due to different issues, only about 30% of my castings ever make it to the lathe, and some of them never make it to a completed pen for various reasons. I have a gallon of PR on the way (probably my 5th gallon since I started making label pens). I just brought and tried some alumilite, got it on Thursday and cast my first 8 blanks with alumilite, that stuff is incredible and worth the extra money if the castings turn out. But all 8 ended up with bubbles around the label.

To make a long story short, the wedding is February 27th, the final guests count who need regular pens is 58, plus 7 in the wedding party who we hoped to make an upscale pen for, and 7 small children I will make them either a kaleidoscope or top. I have only completed 19 pens. I need to complete at least 10 pens a week, I work full time, and with my success rate I would need to cast 30 or more per week. I thought about asking some IAP members to do some castings or make some pens, but I do not have the money to pay a fair price, I may be able to trade some pens blanks, bowl blanks, or pen kits, I have accumulated over the years.

I have my 2nd pressure pot on the way (my old one does not seal that well), I have watched all the tutorials.

Any suggestions you have how I can get 10-15 successful cast per week would be greatly appreciated

 

[jttheclockman]

I have yet to do any casting because I am just putting the parts together for my pressure pot. I did make a few bottle stopper blanks that were just playing around so I know a little bit about it. You do not tell us what your main problems are for the failures.

I suggest you make the shelf design for the pressure pot that Curtis just recently posted here. You can cast a few molds at the same time. Next if you are having problems with the decals I suggest you read the tutorial by Grizz and or search for other topics on this because it has been talked about recently. Some good advise in them. Grub32 has a couple utube videos out recently about casting and you can pick up tips there. There is a wealth of info in the library about the subject.

Like I said if you do not tell us what the problems are we can not narrow it down for you. As far as the time frame goes I say it is doable if you have better success rate. You also need to do things in production manner. Have your tubes ready and mix your resins and pour and watch the temps and also make sure your pot is keeping pressure. As you found out your best bet when casting labels is to use PR. I think most agree on that one. Good luck.

 

[rick_lindsey]

Have you thought about trying a parker-style euro instead of the 7mm euros to get a bigger tube that it sounds like you may be more comfortable with?

-Rick

 

[pentex]

Well, I wish I could help, as it sounds like you might not make all the pens by the deadline. If I knew how to cast the labels, I sure would do it. I will be glad to make some pens if you send them to me and I would not charge you anything. Just offering some help. Let me know.

 

[NewLondon88]

I just brought and tried some alumilite, got it on Thursday and cast my first 8 blanks with alumilite, that stuff is incredible and worth the extra money if the castings turn out. But all 8 ended up with bubbles around the label.

That's been my problem, too. The air seems to be coming from the label,
since I can cast flat and see no bubbles before it goes into the pressure pot.
I'm not sure if it is some sort of reaction with the ink or what.. reminds me
of the neucleation when you drop Mentos into Diet Coke.

I still haven't figured it out. The only place I don't get air bubbles is in the
mixing cup when there's leftover resin. That comes out perfect.

 

[rick_lindsey]

If the label is outgassing, has anyone tried coating it with PU or somesuch before casting?

-Rick

 

[NewLondon88]

If the label is outgassing, has anyone tried coating it with PU or somesuch before casting?-Rick

Oh yeah .. all sots of things. The people who cast successfully say it isn't
needed. I've tried acrylic, lacquer, poly, uncatalyzed PR, CA ..
I've tried different label types.. the only one that didn't form bubbles so far
was the vinyl bumper sticker material.. but it marked up easily and the ends
shrunk back toward the middle.

 

[polarbear1]

Thanks for the reply John, actually if it was one or two issues I would be able to explain it better, but there are a number of issues. Mostly bubbles in the castings. I have had success letting the tubes fill with resin then pushing it out, but sometimes the entire tube comes out, sometimes not. I have put a thin coat of petroleum jelly in the tube as a mold release and the resin pushes out better but the casting looks a little cloudy. I have had the seam showing where the label meets. I have plugged up the holes but air leaks out. I have had small bubbles around the labels. to name a few.

Thanks Rick,
Yes a larger tube would have helped, when I cast my cigar pens I do it in a disposable Tupperware type container the tubes just fit across and run a bolt through the tube and out the other end with a wing nut tighten it down, then pour the resin, no resin ever gets inside the tube and I don't have to dig out a cork. I think I recently read something about a euro with an 8MM tube but I already have purchased a bunch of 7mm euro kits.

Thanks Harold
For that generous offer if I can get most of them to turn out, I can get the lathe work done in time.

Newlondon88

If I figure out a fool proof way I will sure let you know, mostly the bubbles from the labels were when I used aluminite, and the easy peel labels. I will keep working on it and let everyone know the progress.


Thanks everyone for your generous help, this is an awesome group.

Rick

 

[jason_r]

Here's something I'm going to try with some Thistles I plan on casting.
My initial attempts all had lots of bubbles, so I'm planning on casting them
into a vacuum.

I have a PVP, and plan on fitting that down pipe that everyone takes out
with a ball valve on top with some kind of container (piece of pipe likely)
above the valve and connected to it.
1) Close the valve
2) pull a vacuum in the pot.
3) wait and make sure all the air's gone.
4) Mix clear resin and put in container above valve.
5) Open valve slowly to let resin run into mold.
6) Close valve
7) Apply pressure.

No, I haven't tested this. Hopefully I will soon since I'm finally got some
alumilite to cast with.

 

[polarbear1]

It's been said when Thomas Edison was asked if he was a failure because he tried so many times to invent the electric light bulb, his response was "I didn't fail, I now know 4,000 ways not to make a light bulb". I may not be up to 4,000 yet, but I sure know a number of ways not to do the perfect pen casting. Let us know if your idea works Jason, what I'm picturing is a ball valve and PVC all gunked up with alumilite in the trash. But then many people did not think personal computers would catch on.

 

[jason_r]

I have considered the likelihood that the valve will have limited lifespan, and
don't think I'll make 4000 tries on it.

There's also the fact that this will require overfilling the mold to ensure coverage
and as such will waste resin.

Weighing against that is the resin and time I'll waste with bad casts.

Also, if I used PR instead of alumilite I know acetone would clean out the
ball valve. I'm not sure if alumilite will dissolve in acetone.

So all you alumilite guys- will it dissolve in acetone?

 

[GouletPens]

Boy it sounds like that deadline is tight. I know you can get tunnelvisioned sometimes when doing things this important, but you don't want to become resentful about it or even worse not make the deadline. Have you considered just turning pens out of wood or acrylic and laser engraving the names on them? That would still be very personal and would save you an incredible amount of frustration. Good luck to you!