I need some advice about mold!!!

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#1

Hello Guys,

I am going produce carbon fiber cases by vacuum infusion method and
A yacht company made a mold for my cases by Leda One-Shot vinylester resin,but I worry about the mold quality is ok or not, also I am confuse about flanges is long enough for vacum infusion.And there are some damages gelcoat surface on the mold(such a little white points)What is your advice about that?

  1. Do i need to order a new mold?
  2. Which resin is better for mold? epoxy or vinylester?
  3. What epoxy resin is better for mold making?
    I added a capture from my mold.

Thanks.

#2

Kann79,
We make carbon fiber cases for laptops and iPads and utilize several metods including vacuum infusion. Here is a picture of one of our molds.

#3

In my opinion, if you’re paying someone to make your molds, you should be satisfied with the results. Additionally, a company taking your money to make a mold for you should have a bare minimum in terms of what’s acceptable and what isn’t.

For example, and again, this is all my opinion: a 3 cm flange width is unacceptable for the purposes of vacuum infusion. You can make it work, sure, but its going to be a serious pain. Generally, I recommend a minimum width of 10 cm (or 4" US), but the wider the better.

More flange gives you more room to pry against during demolding, plus you have plenty of room in o lay your tacky tape, vacuum or infusion lines, etc…

A 1" flange is nearly unusable.

I can’t see the white dimples, but if the mold face is anything other than smooth like glass, they need to make it again.

Personally, I use a red tooling gelcoat to make all of our molds.

#4

Indeed I can not see the blemishes, as the picture quality is too low.

On materials: Both epoxy and vinylester perform very well, it is all a matter of how much heat you want to add, how many parts, desired surface quality, repairability, and how much money you like to spend.

On flanges: too narrow to my liking, I can just repeat what BigTopGT just said (I wont)

But I have no idea what communication you have with the tool builder. In my experience you need to specify everything and everything. That is the only way to get a tool you want.

#5

Let me try this again.

#6

Thanks for your replies,
Herman, First of all sorry for bad quality pictures.Heat is over 80 degree and surface quality should be as perfect as possible, such a glass. I want to use this mold making for around 500 musical instruments hard cases and by carbon fiber or hybrid carbon kevlar.I have spend 2500 euros just for mold.But I want them make it again for me because I am not satisfied with the results.

#7

Brother, if you send me the original part, I’ll make the mold for you for $1800 Euros. :slight_smile:

#8

500 parts on a composite mold is wishful thinking unless the shape is very, very, friendly.

Why not make the mold yourself? If you can make parts you can make a mold.

#9

500 parts is not that uncommon. At least not in the polyester business.

#10

Agreed. It really depends on the shape. I was speaking out of my experience of multi-piece molds that make tidy seamed hollow parts that come out the mold perfectly painted. I ignorantly forget that not everybody does what I do. :o

#11

Sharp seam lines in multipart moulds indeed suffer. I still have to see the first split boat mould which after producing 10 products, does not need refinish on the seam line. It actually is an accepted phenomena. (reworking the seam lines on parts)

#12

When I said 500 parts I did not really mean I am gonna add 500 parts perfectly, probably 20 percent of them go for rubbish because I am not composite expert like you guys :slight_smile: so I cant make my own mold by myself at the moment.I am keep wishing maybe one day I can make it.I just want to make sure about what is the difference between epoxy and vinylester mold?I heard that epoxy mold surface quality is better and longer lasting than vinylester mold.

#13

When I said 500 parts I did not really mean I am gonna add 500 parts perfectly, probably 20 percent of them go for rubbish because I am not composite expert like you guys :slight_smile: so I cant make my own mold by myself at the moment.I am keep wishing maybe one day I can make it.I just want to make sure about what is the difference between epoxy and vinylester mold?I heard that epoxy mold surface quality is better and longer lasting than vinylester mold.

#14

A vinylester tooling gelcoat can be polished to a very high gloss, and in normal use should do the job perfectly. It also is relatively easy to repair.

#15

Just a word off caution,in the past all my molds made from epoxy,been working on fuel tank,and have used unimold system I’ve been off work for the week sick as a pig throwing up headaches over exposure just be warned safety first.

#16

I am sorry heard that shaneer22 and thanks for warning about that,I will keep in mind.
you scared me:)