Helmet base by vacuum forming or slush casting?

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Teacherinspace

Member

• Nov 13, 2013

• #1

I would need an opinnion from more experienced helmet makers. I plan to make this astronaut helmet. Visors will be vacuum formed over mold. But what about helmet itself? If it is vacuum formed it has to be done in 2 parts and there will be visible seam in ear area. Maybe making hollow mold and slush casting would work better?

What do you think? Any help or ideas woul be highly prized!

 

T

Teacherinspace

Member

• Nov 14, 2013

• #2

One more guestion: is wood or plywood good material for vacuum forming molds?

 

Psicorp7

Sr Member

RPF PREMIUM MEMBER

• Nov 15, 2013

• #3

I would vacuum form the helmet in two pieces since it seems you have access to the machine. It will be much lighter and easier to add the visor and sliders (more room inside). I would do the mold with the seam running down the middle (center of forehead to middle of back of the neck). A layer of fiberglass mat on the inside and a quick bit of body filler on the outside will hide the seam nicely.

I have found that MDF is the best material for the base of vacuum form molds. Build up fine details with thin mdf or body filler and then give it all a smooth coat of filler and you are good to pull alot of plastic! Remember, if you have to pull details in the middle of the mold you might need to add vents in the mold to get the vacuum to those spots.

Good luck and keep us updated!

 

laxman09

Active Member

• Nov 15, 2013

• #4

if you're even just using the mold once, you could make it out of high-density foam, throw some baby powder on top of it and be all good!

 

T

Teacherinspace

Member

• Nov 15, 2013

• #5

The helmet is rounded (especially back of the neck), so if I vacuum form it as in one piece, finished helmet will be stuck over the mold. Or did I misunderstand you somehow?

 

laxman09

Active Member

• Nov 15, 2013

• #6

My apologies, i should've been a bit more clear about that! i meant that you could make the helmet as a two separate parts and do two vac forms like psi suggested. same concept, but different mold material!

 

T

Teacherinspace

Member

• Nov 16, 2013

• #7

laxman09 said:

My apologies, i should've been a bit more clear about that! i meant that you could make the helmet as a two separate parts and do two vac forms like psi suggested. same concept, but different mold material!

Click to expand...

Is glueing these 2 parts together difficult? Is there trics for doing that?

 

T

Teacherinspace

Member

• Nov 20, 2013

• #8

I will start to make molds soon, but before I need to know is it possible and ok to glue 2 halfs together? What you think? If seam is in front of ears seam will hide under rubber and hinge.

 

laxman09

Active Member

• Nov 23, 2013

• #9

of course, gluing the two parts with plastic-bonder epoxy or using fiberglass is going to be the only way you'll be able to produce the helmet through vac-forming. you can have a seam anywhere, because you can just fill in the gap with filler, so it will vitrually be invisible!

 

T

Teacherinspace

Member

• Dec 1, 2013

• #10

laxman09 said:

of course, gluing the two parts with plastic-bonder epoxy or using fiberglass is going to be the only way you'll be able to produce the helmet through vac-forming. you can have a seam anywhere, because you can just fill in the gap with filler, so it will vitrually be invisible!

Click to expand...

Thanks. I probably have to ask more detailed guestions latter.