Subject:
|
Re: LEGO meeting the engraver
|
Newsgroups:
|
lugnet.trains
|
Date:
|
Fri, 10 May 2002 19:55:56 GMT
|
Viewed:
|
545 times
|
| |
| |
Erik,
As someone with a little molding experience (sand casting for metal, and
injection molding), I understand what you're saying. I thought for a while
about how to do that, and you are right, you do need a moving cam inside the
mold so the part can be freed from the mold without.
I'm still curious if Lego uses hot runners or not when molding...
Scott Lyttle
>
> Milling grooves into the parts can get you designs that would be impossible
> or at least costly to mold into the part.
>
> Molding a texture on the side of a brick is expensive. It requires more
> moving parts in the mold, in particular a "split cavity" that expands around
> the part instead of just moving away, or the part will not be able to slip
> out of the mold.
>
> The great example is the 1x2 corrugated brick. If you look at one you will
> see the evidence for the mold's parting line going up the end faces of the
> brick. This implies that there are two halves of the mold which move away
> from this line--a split cavity. Producing a plastic part on this method has
> many drawbacks versus a part with smooth walls. And there's a reason why the
> corrugated brick is smooth on the two ends.
>
> There are a lot of other techniques that bear on this but I'll leave it at that.
>
> (I don't have any HP sets so I can't look at the textured arch.)
>
> -Erik
|
|
Message is in Reply To:
| | Re: LEGO meeting the engraver
|
| (...) This is really cool, Steve. Milling grooves into the parts can get you designs that would be impossible or at least costly to mold into the part. Molding a texture on the side of a brick is expensive. It requires more moving parts in the mold, (...) (23 years ago, 10-May-02, to lugnet.trains)
|
19 Messages in This Thread:
- Entire Thread on One Page:
- Nested:
All | Brief | Compact | Dots
Linear:
All | Brief | Compact
|
|
|
|