How was this molded?

This is a nose cone of a toy glider. I'm trying to figure out how to make a similar one. It is hollow, ~5" long, with a wall thickness of ~.014". Notice the D shape at the tip and the small round hole - perhaps they are clues. Is it likely injection molded or vacuum formed or something else? I can barely see a seam all the way around and at one spot the seam is not so uniform hinting at sealing by manually pressing a heating element to seal but the rest of the seam seems too clean for that.
https://www.cnczone.com/forums/attac...d=470724&stc=1

I'd guess it's blow molded, but I'm not sure...

Probably blow or centrifugal molding. Both can result in no seam because they expand a uniform pellet.

The hole is to allow airflow as it expands.

Not my area of direct experience though, hopefully someone with more knowledge can weigh in. I've only done injection molding.

That seam might be a witness line where two mold halves fit together, rather than a true seam.

Otherwise it might have been two molded halves that are welded together, with that hole being a locating pin that they for some reason stuck through the part... but I'm still leaning towards a blow/spin mold.

As soon as I saw the photo I thought blow molded just as others have said. I worked in injection, blow, and rotational molding for 12-13 years.

How about gas-assisted injection molding? Such as this:

_https://www.youtube.com/watch?v=xFcDKsP4418_

You might need to cut and paste as it does not allow url link.

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Originally Posted by swisscheese

This is a nose cone of a toy glider. I'm trying to figure out how to make a similar one. It is hollow, ~5" long, with a wall thickness of ~.014". Notice the D shape at the tip and the small round hole - perhaps they are clues. Is it likely injection molded or vacuum formed or something else? I can barely see a seam all the way around and at one spot the seam is not so uniform hinting at sealing by manually pressing a heating element to seal but the rest of the seam seems too clean for that.
https://www.cnczone.com/forums/attac...d=470724&stc=1

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I can't see the drawings or other things you sent, only the text, so I can't answer your question. But I know that most common plastics are solved by processes such as injection molding or blow molding. If you need it, you can send me an email [email protected]