Cheap Mold Tested

[XanderPen]

Attached photos from the sales page; you should be able to find these on temu/bangood/Ali. They are decent and around $10-12USD. I've had 4 successful casts so far with them.

My other cast mold was imported from the US; lasted about 2 casts and cost me around $90USD.

 

[Woodchipper]

$204.96 for a mold? How many castings would it take to break even? Curious.

 

[hooked]

$204.96 for a mold? How many castings would it take to break even? Curious.

I think that is in Thai Baht. Conversion to dollars is about $5.50.

 

[egnald]

$204.96 for a mold? How many castings would it take to break even? Curious.

Not very many. At today's exchange rate 204.96 Thai Bahts(THB) is only about $5.60 (USD).
And buy 3 for free shipping! - Dave
PS I never thought about using candle molds for pen blanks though - interesting idea.

 

[Woodchipper]

Thanks for the clarification on the currency exchange. Printing wasn't clear on that. I now see the price on the original post. Missed it. Missed a lot of things over the years.

 

[brainick]

Attached photos from the sales page; you should be able to find these on temu/bangood/Ali. They are decent and around $10-12USD. I've had 4 successful casts so far with them.

My other cast mold was imported from the US; lasted about 2 casts and cost me around $90USD.

I am having a hard time separating blanks from PVC pipe and looking for something like that. I found that exact article for about 20USD and it is also okay for me. Could you please inform me about the diameter of the holes? That is important for me to know and it is not mentioned in the item's description that I found.

 

[egnald]

I am having a hard time separating blanks from PVC pipe and looking for something like that. I found that exact article for about 20USD and it is also okay for me. Could you please inform me about the diameter of the holes? That is important for me to know and it is not mentioned in the item's description that I found.

Are you using an appropriate mold release spray before pouring into the PVC pipe? I use Alumilite Clear Slow and a very light spray of mold release and have never had any difficulty getting the cured blanks to come out of the mold. Alumilite sells their own brand of mold conditioner/release, (Amazing Mold Release) ; however, I use a product called Stoner Urethane Mold Release.

I also turned a 3/4-inch wood dowel down so that it just fits inside the PVC pipe to use as a tool to nudge the blanks out if they don't push out easily with my fingers. In the USA anyway, 3/4-inch Schedule 40 PVC pipe (white) has an ID of 0.804-inches, but I use 3/4-inch Schedule 80 PVC pipe which has an ID of 0.742-inches. The smaller ID of Schedule 80 helps me save resin.

Regards,
Dave

 

[Hippie3180]

Are you using an appropriate mold release spray before pouring into the PVC pipe? I use Alumilite Clear Slow and a very light spray of mold release and have never had any difficulty getting the cured blanks to come out of the mold. Alumilite sells their own brand of mold conditioner/release, (Amazing Mold Release) ; however, I use a product called Stoner Urethane Mold Release.

I also turned a 3/4-inch wood dowel down so that it just fits inside the PVC pipe to use as a tool to nudge the blanks out if they don't push out easily with my fingers. In the USA anyway, 3/4-inch Schedule 40 PVC pipe (white) has an ID of 0.804-inches, but I use 3/4-inch Schedule 80 PVC pipe which has an ID of 0.742-inches. The smaller ID of Schedule 80 helps me save resin.

Regards,
Dave

I second what Dave says. We use Stoner, never a problem (unless I forget to spray) even then we are able to get the blank out with some work.

 

[egnald]

In case you are interested, here is a link to the PVC Pipe Vertical Casting Mold (tutorial) that I built. The tutorial shows the white schedule 40 PVC which has an ID of 0.804 inches; however, I have since changed to the Grey Schedule 80 PVC which has a slightly smaller ID of 0.742 inches because it helps me save resin. - Dave

 

[XanderPen]

I am having a hard time separating blanks from PVC pipe and looking for something like that. I found that exact article for about 20USD and it is also okay for me. Could you please inform me about the diameter of the holes? That is important for me to know and it is not mentioned in the item's description that I found.

Noooooo dont pay $20... Keep looking on temu, aliexpress, banggood, taobao; they cost me around $5USD. Check out Aliexpress "choice" they usually have a deal where if you order 5 items there is a large discount. Or add it to your aliexpress cart and logoff; they will drop the price and annoy you via email for a few days.

I have 16 pours now; the mold is still good; but nothing lasts forever. I ordered a few more because I would really like to convert them to "tube in" with a brass rod

About 20mm. I have been pouring all day; polyester resin + cobalt + MEKp... no cure inhibitions or weird reactions (so far). I was using different ratios of mekp, this mold literally smoking hot and it is fine.

words of caution;

1. this is actually a very soft mold, so you cannot lean it and pour on the side; the blank will come out bent. I would avoid sticking sharp objects in the holes to mix around the resin.

2. The only way to demold this is with compressed air. Use caution when demolding with compressed air; the smoking hot blanks shoot out like a m777 howitzer!

3. The polyester casters; this is a deep pour for polyester resin and they get real hot; there has to be a temp limit on these; I have not found it yet.. since it was designed for hot wax I AM GUESSING 200-250C.

 

[XanderPen]

In case you are interested, here is a link to the PVC Pipe Vertical Casting Mold (tutorial) that I built. The tutorial shows the white schedule 40 PVC which has an ID of 0.804 inches; however, I have since changed to the Grey Schedule 80 PVC which has a slightly smaller ID of 0.742 inches because it helps me save resin. - Dave

PVC vs polyester resin never worked well for me; I tried the blue pvc, grey "UVPVC", black pvc (used for sprinkler systems). I prefer these cheap silicone molds at $5USD the mold is actually cheaper than a can mold release spray.

 

[brainick]

Are you using an appropriate mold release spray before pouring into the PVC pipe? I use Alumilite Clear Slow and a very light spray of mold release and have never had any difficulty getting the cured blanks to come out of the mold. Alumilite sells their own brand of mold conditioner/release, (Amazing Mold Release) ; however, I use a product called Stoner Urethane Mold Release.

I also turned a 3/4-inch wood dowel down so that it just fits inside the PVC pipe to use as a tool to nudge the blanks out if they don't push out easily with my fingers. In the USA anyway, 3/4-inch Schedule 40 PVC pipe (white) has an ID of 0.804-inches, but I use 3/4-inch Schedule 80 PVC pipe which has an ID of 0.742-inches. The smaller ID of Schedule 80 helps me save resin.

Regards,
Dave

I am not sure if I am using the right spray. I just ordered it from amazon as "Epoxy resin release agent". I tried to cast epoxy and I used that spray. I tried to make 2 pieces pen blanks and 2 pieces shaving brush blanks. With shaving brush molds (pipes) which have 5cm diameter and 8 cm length, I didn't have any problem by taking the blank from the mold. However, I had the problem with pen blanks (pipes), they were 2x20cm.

Now, when I am trying to explain things, I think I found my mistake. That was my first experience by the way. I used the release spray after closing the end of the mold for both shaving brushes and pen blanks. So, since the pen pipes are deeper (20cm), spray couldn't reach at the bottom of the pipe. And since shaving brush molds have bigger diameter and shorter length, I didn't had the same problem with them. Not sure really! I have to try again with open ended pipes.

Btw, I like your system Dave, very clever and efficient!

Ahmet

 

[brainick]

Noooooo dont pay $20... Keep looking on temu, aliexpress, banggood, taobao; they cost me around $5USD. Check out Aliexpress "choice" they usually have a deal where if you order 5 items there is a large discount. Or add it to your aliexpress cart and logoff; they will drop the price and annoy you via email for a few days.

I have 16 pours now; the mold is still good; but nothing lasts forever. I ordered a few more because I would really like to convert them to "tube in" with a brass rod

About 20mm. I have been pouring all day; polyester resin + cobalt + MEKp... no cure inhibitions or weird reactions (so far). I was using different ratios of mekp, this mold literally smoking hot and it is fine.

words of caution;

1. this is actually a very soft mold, so you cannot lean it and pour on the side; the blank will come out bent. I would avoid sticking sharp objects in the holes to mix around the resin.

2. The only way to demold this is with compressed air. Use caution when demolding with compressed air; the smoking hot blanks shoot out like a m777 howitzer!

3. The polyester casters; this is a deep pour for polyester resin and they get real hot; there has to be a temp limit on these; I have not found it yet.. since it was designed for hot wax I AM GUESSING 200-250C.

Thank you for the detailed information, for me here, compressed air would be a dealbreaker because I don't have any compressor or air gun. I am pressing my pot with a simple electric tire pump. I will try more with pipes and hopefully with better results

BR,

Ahmet

 

[XanderPen]

Thanks for the clarification on the currency exchange. Printing wasn't clear on that. I now see the price on the original post. Missed it. Missed a lot of things over the years.

Sorry about that; its around $5USD; then I get cashback and free shipping for ordering 5. The shopping app is basically an alibaba port; they actually own it; you should be able to find the same things for around the same price on aliexpress.

 

[XanderPen]

Yo

Thank you for the detailed information, for me here, compressed air would be a dealbreaker because I don't have any compressor or air gun. I am pressing my pot with a simple electric tire pump. I will try more with pipes and hopefully with better results

BR,

Ahmet

I just demolded a batch without compressed air; i had to pull and twist and they came out kinda easily.