PDA

View Full Version : Chocolate Mold Failure



Dee Gallo
10-14-2009, 1:57 PM
Well, I tried, but nothing good happened. First, I started with Corian, but it was going to make a very choppy surface and take too long. Switched to 1/4" plexi layers. This system would work very well if you only want a shape with no raised design.

The laser rasters with lines, even though small at 600 pdi, it did not release the chocolate from the mold completely. It might work if I coat the mold with a release material like powdered sugar.. could have left the plexi powder instead of cleaning it out, but who wants to eat that? :D

The absolute smoothness of the plexi could be the reason it didn't release... maybe a small texture would help with the vacuum formed between the two.

BUT! I can see that you could make shapes very easily with 2 pieces, a cut out and a base. I recommend making them NOT line up perfectly, it makes it easier to separate after you take them out of the freezer.

The mold making part was fast and easy, the melting and tempering of the chocolate takes more time.

Oh well, you never know til you try!

cheers, dee

Steve Clarkson
10-14-2009, 2:28 PM
I actually found that the white chocolate chips worked better than semi sweet chips.

Alexander Stein
10-14-2009, 2:31 PM
Could you flame polish the inside of the etch to smooth it out for a better chocolate release and a better final image? Maybe a spray of pam...?

Rodne Gold
10-14-2009, 2:33 PM
Try melted butter brushed in , worked for the moulds I made my kid My mould was 2 piece so it came out easily

Brian Robison
10-14-2009, 2:41 PM
Use the stamp option when lasering, that will give you enough draft to help the part release. In injection molding we use 1.5 deg per side or so. The stamp option would be way over that. Don't give up. Send any trial parts to 501 N. Jefferson Street Shelbyville Tn care of Brian Robison. Be happy to, uhm, evalu ate them.:rolleyes:

John Noell
10-14-2009, 3:20 PM
We've done several molds for a local chocolatier. They do not mind the slight rastermarks on the raised portions (resort logos mostly) as they think it improves contrast against the rest of the surface which is smooth. I minimize them by rastering twice at different DPI settings (400 & 300). That way the dot placeent varies between passes. They also use a two piece mold with the logos engraved in the flat bottom. The chocolate pieces stay with the top (simply squares cut in 5mm acrylic) when the mold is separated and can be easily pushed out.

Ed Harrall
10-14-2009, 3:29 PM
I use a candy mold project it in one of my manufacturing projects for my students. I have them research mold making and go on and make the mold. Most do not come up with the need for draft on the mold or mirror of text. It really messes with their minds.http://www.sawmillcreek.org/images/icons/icon10.gif Sometime we still have to use a release agent. I like the bakers pam. puts a flour coat on the mold that most of the time stays on mold and not candy.

Ed

Hilton Lister
10-14-2009, 3:40 PM
if you take the laser out of focus for thje final pass, will this not have the effect of smoothing out the raster lines somewhat?

Dee Gallo
10-14-2009, 4:30 PM
Lots of good ideas, thanks everyone! Tomorrow I'll give it another go and see what happens.

Brian - I tried the stamp mode but it did nothing - literally. Just beeped as if I was trying to vector a raster only image, even though I had combination selected. Probably should read the manual to find out what to do, eh?

John - I like the 300/40 dpi thing - makes a lot of sense. That's on my list of things to do!

Alex - flame polishing is not my thing. I'm not as fond of playing with fire as the rest of the Creekers are. But the focus thing does make some sense too, as Hilton suggested.

Thanks to everyone, you guys are great! Hopefully there will be some success soon!

cheers, dee
But I will try both baker's Pam and butter for release agents.

Dee Gallo
10-14-2009, 4:34 PM
We've done several molds for a local chocolatier. They do not mind the slight rastermarks on the raised portions (resort logos mostly) as they think it improves contrast against the rest of the surface which is smooth. I minimize them by rastering twice at different DPI settings (400 & 300). That way the dot placeent varies between passes. They also use a two piece mold with the logos engraved in the flat bottom. The chocolate pieces stay with the top (simply squares cut in 5mm acrylic) when the mold is separated and can be easily pushed out.

I just read your post again - can you please clarify something for me? Is the main bottom part one big piece which has a bunch of small squares set on top so that each chocolate piece comes out separately with the square around it?

:) or am I completely reading that wrong?

George D Gabert
10-14-2009, 5:20 PM
Dee

You might try your 3D procss to make the edges with the required bevel.

Also if there is some way to put a radius or corner chamfer at the bottom (side with design) will help with the edges / corners cracking off.

Regards
GDG

Steve Clarkson
10-14-2009, 6:21 PM
Dee,

To use the stamp mode you need a fence.....just put your image inside TWO rectangles.

I'm amazed other people got the mold with acrylic to work.......

Dee Gallo
10-14-2009, 6:52 PM
Dee,

To use the stamp mode you need a fence.....just put your image inside TWO rectangles.

I'm amazed other people got the mold with acrylic to work.......

Thanks, Steve!

I never would have guessed that one - you've been a big help! It didn't make any sense that it just beeped at me.

:D dee

John Noell
10-14-2009, 7:21 PM
I just read your post again - can you please clarify something for me? Is the main bottom part one big piece which has a bunch of small squares set on top so that each chocolate piece comes out separately with the square around it?

:) or am I completely reading that wrong? You are right. One big bottom piece with lots of logos. The top piece has a bunch of 1" (usually) squares cut out. The thickness of the top piece is the thickness of the finished chocolate pieces (except for the slightly raised logo part). Apparently the thickness (but also stiffness) of the bottom plate is critical in the tempering or something like that. (As they describe their process it is very complicated. They are starting with raw cacao pods, then fermenting etc. etc.) They just use a spatula to smooth the softened chocolate into the molds, cool them, separate the mold pieces, and pop out the chocolate squares. For only $10,000 you can stay at the local Namale resort & Spa for one week - and they will put one of these chocolates on your pillow each night. :)

John Noell
10-14-2009, 7:24 PM
John - I like the 300/40 dpi thing - makes a lot of sense. That's on my list of things to do!
Ooops, forgot to add I do the 2nd(different DPI) pass slightly out of focus as well. Definitely helps!

James Jaragosky
10-14-2009, 8:06 PM
Ooops, forgot to add I do the 2nd(different DPI) pass slightly out of focus as well. Definitely helps!
I made some molds for a local soap maker. I had similar release problems. I switched to a .5 thick Teflon product, nothing sticks to it.:)

Dan Hintz
10-14-2009, 8:24 PM
I made some molds for a local soap maker. I had similar release problems. I switched to a .5 thick Teflon product, nothing sticks to it.:)
Be very careful with this... Teflon, if heated high enough to burn it off (around 600F+, becomes a wonderful cancer-causing agent when breathed in.

James Jaragosky
10-14-2009, 8:40 PM
Be very careful with this... Teflon, if heated high enough to burn it off (around 600F+, becomes a wonderful cancer-causing agent when breathed in.
The soap never reaches temperatures over 200F
and I think chocolate burns at even lower temperatures.
Infact I believe that the chocolate mold is usually refrigerated not cooked.

Richard Rumancik
10-14-2009, 10:33 PM
James, I think Dan is concerned with lasering Teflon, not the soap/chocolate temperature. Or did you machine the molds on a CNC mill? That's a different ballgame. So while Teflon may be a solution for a machined mold, it is not advisable to laser Teflon.

James Jaragosky
10-14-2009, 11:05 PM
James, I think Dan is concerned with lasering Teflon, not the soap/chocolate temperature. Or did you machine the molds on a CNC mill? That's a different ballgame. So while Teflon may be a solution for a machined mold, it is not advisable to laser Teflon.
I machined them. but with the fumex system I have hooked to my laser I am not worried about the toxic fumes.
thanks for setting me straight.

Richard Rumancik
10-14-2009, 11:36 PM
Dee, take a look at this site that makes molds for chocolates:

http://customcandymolds.com/productinformation.html

Scroll down and you will see that they laser their patterns out of extruded acrylic. (A pattern is the opposite of a mold.)

Looks like they make the patterns, then vacuum form the FDA-approved film over the pattern. Not sure of the film material but you could proably find out. You could probably use a food grade PETG (like soda bottles).

The hitch is coming up with a low-cost vacuum forming technique. If interested in this path, find a copy of this book: "Do it Yourself Vacuum Forming for the Hobbyist" by Douglas Walsh.

This two-step method probably takes more work and equipment than you had hoped.

Engraving the mold directly (instead of making a pattern to make a mold) is obviously easier, if you can find a process and material that works. If you want to use the direct method, I think the two-piece mold has the best chance of success.

There is probably a market for custom chocolates for Wedding and Anniversary receptions, etc.

Mike Null
10-14-2009, 11:55 PM
The problem chocolate makers have with vacuum formed molds is that they can't get the detail they want.

Dee

try cornstarch as your release agent.

Scott Challoner
10-15-2009, 10:08 AM
Dee

Another thing to minimize raster lines is to use a texture fill instead of just black. If I'm engraving a large area, I usually use stucco. You can go to the advanced setting and change the two levels of black. I usually use 100% and 70%. Then engrave in 3d. I also lower the table by .80" to .100". You end up with kind of a sand cast appearance. I imagine if you want a smoother look, you make the two numbers closer together. I think the de-focusing is the key.

HTH

Chris Tatarian
10-15-2009, 11:29 AM
I would laser engrave a reverse image and cast it out of food grade RTV. Silicone will release food much easier than a more solid mold. Repeatablity is much more robust.:cool:

Chris Tatarian

Mike Null
10-15-2009, 12:20 PM
Chris

I agree with your idea. In fact when trying to find a solution for a local candy maker I ordered some. Like many things I haven't got around to trying it yet.

Rob Bosworth
10-15-2009, 12:29 PM
James, you NEED to be VERY careful cutting teflon. When the teflon is laser cut, it releases TFE's, which is some really bad stuff to breath. You don't want to breath it.

A number of years ago, The Queen and I were sitting out on a deck overlooking the palatial estate, having an adult beverage, enjoying the evening. We knew the boys were downstairs with some buddies. We heard the exhaust blower start up, and we both just grinned thinking how cool is that that the 11 and 13 year old were comfortable enough with the machines that they could run them and do something with them. Maybe 30 seconds later, we were deathly sick, and were having trouble breathing. I ran downstairs to figure out what was going on. Turns out they were engraving their names on ping pong paddles. The "sponge" on the paddles were made out of a teflon. The nausea and breathing difficulties went away in a couple of hours. But we certainly are more careful as to what we laser since then.

James Jaragosky
10-15-2009, 1:28 PM
James, you NEED to be VERY careful cutting teflon. When the teflon is laser cut, it releases TFE's, which is some really bad stuff to breath. You don't want to breath it.

A number of years ago, The Queen and I were sitting out on a deck overlooking the palatial estate, having an adult beverage, enjoying the evening. We knew the boys were downstairs with some buddies. We heard the exhaust blower start up, and we both just grinned thinking how cool is that that the 11 and 13 year old were comfortable enough with the machines that they could run them and do something with them. Maybe 30 seconds later, we were deathly sick, and were having trouble breathing. I ran downstairs to figure out what was going on. Turns out they were engraving their names on ping pong paddles. The "sponge" on the paddles were made out of a teflon. The nausea and breathing difficulties went away in a couple of hours. But we certainly are more careful as to what we laser since then.
Bob I currently use this as my filter system. http://fumexinc.thomasnet.com/item/air-filtration-systems/fa1-mini-air-filtration-system/item-1001?&forward=1 (http://fumexinc.thomasnet.com/item/air-filtration-systems/fa1-mini-air-filtration-system/item-1001?&forward=1)
I will take your warning to heart. You can never be too careful.

Martin Boekers
10-15-2009, 2:06 PM
Dee, interesting! So many ideas.

I did a quick search on mold making and found this.

Of all people Martha Stewart had a chef on who came up with a mold base.
This looks cool and easy to do. We can make the laser template than easily make a silicon food safe mold.


http://www.makeyourownmolds.com/videos

There is a bunch of things out there on the actual making of molds for candy soaps etc.

We have the template maker already in our hands.


Now if I only had more time!

Marty

Dee Gallo
10-15-2009, 4:06 PM
Martin, I LOVE this site! Thanks for posting it, I'm sold on silicone already, it's one of my favorite materials all over my kitchen.

I can make the positive on my laser and make the mold out of this stuff! Yay!

Thank you thank you!!!

:D dee

Mike Null
10-15-2009, 6:07 PM
Dee

some of the RTV suppliers will give you a free sample of silicon--enough to do quite a few molds. Just ask for food safe rtv. It's common.

Dee Gallo
10-15-2009, 6:16 PM
Dee

some of the RTV suppliers will give you a free sample of silicon--enough to do quite a few molds. Just ask for food safe rtv. It's common.

Thanks, Mike... but I already ordered some of the stuff this site offered - what the heck? But I will remember that if I decide I need more. :D

cheers, dee

Bill Cunningham
10-15-2009, 11:01 PM
Dee if you have a way of putting it in a vacuum after mixing to allow it to bubble off all the mixed in air, it will not only pour smoother, but will eliminate the chance of having a blister show up on the inside of your initial mold..

Dee Gallo
10-16-2009, 6:30 AM
Thanks for the heads up Bill, but that's why I bought the kind that is more like 2 part epoxy. You mix the 2 parts like soft clay and press it over the template in small pieces to make sure there are no air pockets... fool (me) proof! It air cures on about an hour, so no baking either.

cheers, dee

- plus it's a pretty blue:)

George Brown
10-16-2009, 11:24 AM
Thanks for the heads up Bill, but that's why I bought the kind that is more like 2 part epoxy. You mix the 2 parts like soft clay and press it over the template in small pieces to make sure there are no air pockets... fool (me) proof! It air cures on about an hour, so no baking either.

cheers, dee

- plus it's a pretty blue:)
Dee, where did you find that material?

Albert Nix
10-16-2009, 11:35 AM
Dee I just had a thought...What if you vector cut the elements of the mold and glued them together?

Dee Gallo
10-16-2009, 12:41 PM
Dee, where did you find that material?

I went to "makeyourownmolds.com" (posted by Marty, thanks!) where they have a 4 part video on how to use this stuff. The video was enough to convince me this was the right stuff to use for my purposes.

Al- the making of the mold was not my problem as much as the releasing. This silicone stuff will "unwrap" from the chocolate, making it foolproof (read "me-proof"). But I will still be making the template with my laser of course!

cheers, dee

James Jaragosky
10-16-2009, 12:56 PM
I went to "makeyourownmolds.com" (posted by Marty, thanks!) where they have a 4 part video on how to use this stuff. The video was enough to convince me this was the right stuff to use for my purposes.

Al- the making of the mold was not my problem as much as the releasing. This silicone stuff will "unwrap" from the chocolate, making it foolproof (read "me-proof"). But I will still be making the template with my laser of course!

cheers, dee
Any of the chain craft stores carry a similar putty.
Micheal's does for sure.
I do not know if what they sell is food grade.
the stuff that Dee purchased from the Makeyourownmold site is food grade.

Andrea Weissenseel
10-19-2009, 4:21 AM
This is a great link Marty, thank you for finding that :)