Large parts Molding techniques

[MBG]

I know that to mold a part that is about 40 inches wide I would need a BIG mold and about 3k in material alone to make it for injection. Is there any other processes for making big parts?

[svenakela]

I think you have to explain what the part look like and it's purpose. If it can be made in plastics maybe vacuum forming is good enough, or if composite material can be used you can do it with hand layup or vacuum bagging.

Regards,
Sven

[MBG]

I already know about these processess the vacum bagging would work but it is to sloppy I think...

[MBG]

How good do you thin the vacum bagging would turn out?

[mxtras]

Is this a structural thing? How many do you intend to make? What is the resin and reinforcement, if any (What material will the part be made from)? Are you on a tight budget? Do you have math data for it?

These are basic questions required to make a decision and will help narrow the field. There are countless methods employed by manufacturers - the above questions many times dictate the process and therefore drives the tooling.

Scott

[MBG]

Originally Posted by mxtras Is this a structural thing? How many do you intend to make? What is the resin and reinforcement, if any (What material will the part be made from)? Are you on a tight budget? Do you have math data for it? These are basic questions required to make a decision and will help narrow the field. There are countless methods employed by manufacturers - the above questions many times dictate the process and therefore drives the tooling. Scott

I kind of don't wnat to say what it is... Yes it is sort of a structural thing a lot of banging... How do I intend to make it? Well I wnated to inject it but waaay to costly for tooling.. No resin and reinforcement I wnat to find a type of plastic that looks good and is strong... Math data???

[svenakela]

Then go for vacuum forming, it's a pure plastic forming method. There are many different types of plastics for this method, even fibre reinforced.

http://www.bpf.co.uk/bpfindustry/pro...um_forming.cfm

[daveelc]

MBG,
How about rotational molding, toolings cheap can be fabricated, size not a problem just depends if the molding needs internal accuracy.

[jasire]

I come from a long Vacuforming background. There aren't many things that can't be Vacuformed, you just need to Design around certain limitations. Size is not one of them. Cost is very resonable if you can do the tooling and CAD work. It's a good alternative to Injection Molding. Good for prototyping also.

[Unabiker]

Originally Posted by MBG I already know about these processess the vacum bagging would work but it is to sloppy I think...

Wet lay-up can be sloppy, but it can come out really nice if you know what you're doing.
Pre-preg is not sloppy at all, but more equipment intensive. It'll come out as nice as the mold.
Material cost for a composite will be way higher than vac form.