What material to use for moulds

[Chris Flint Two Ft Pty Ltd]

I have a customer that gives me moulds to rout on the CNC router, they then take these moulds, add a surface coating and make carbon fibre parts from them.

I started using hardwoods, but I got a fair bit of chip out that meant a lot of hand dressing.

So I moved to MDF which seems good and everyone is happy, however, is there a better material which is homogenous and will rout fast without chipout and give a better surface than MDF.

Procedure to date has been to "rough pocket" then to "parrallel spiral", then to "left over" the moulds are small about 300 X 200 X 55 deep and take around 5 hours to machine using a 0.2 stepover in the second and last machining operation any advise here?

thanks

chris f

[betts]

Well Chris I don't know about "carbon fiber" molding, I have only seen that used as an additive to some type of resin. If that is the case then what we call "renwood" is often used for thermoforming molds and would probably do the job. It is considerably softer than MDF but I guess it depends on your needs. It may work for you.

 

HTH

[gavetta]

OBO Modulon (polyurethane board like "renwood")in a heavy density might work well. There's a few suppliers of this type of material. Google search it:)

[Jim at Gentex]

Chris,

 

You shoul be able to find something here

 

We use these modeling boards for many applications like vacuum forming tools, prototype injection mold cavities, and wet layup composite tools. They have a wide variety of materials and densities to choose from, so I'm sure you can find something that works for your application.

[les]

Something I have done for paint grade work in MDF is to use a spray on automotive filler just before the last pass. The MDF soaks it up and your left with a very nice finish.

I would ask if it's compatable with their coating.

It's dry in under 15 min.

 

just a thought.

 

Chimo Les

[Jake Statz]

We use RenShape Material for our prototype molds. They have all sorts of styles for lots of different applications. Just do a Google search and you can find all sorts of information.