Is 3D printing the best way to execute my composites mold project?

Discussion in 'Software and Applications' started by JoshJenny, Mar 19, 2011.

  1. JoshJenny
    JoshJenny New Member
    Hello everyone!

    I am an engineering student who seeks outsides ventures in the world of motorsports in my spare time. I am currently building a BMW M3 for the purposes of road racing and tarmac rallies. I have been developing this car for 2 years and I have recently entered the world of composite fabrication.

    Among many other projects, I am currently in progress of developing several air inlet ducts. I have been going about this in a more primitive way by shaping a moldless design via foam, laying over it, dissolving my foam, and then laying material on the inside of my piece as a re-usable mold, made of fiberglass strand mat/resin with a gel coat finish. This is working out pretty well, but since I have found my introduction in CAD in the past year, I can't help but want to be 100% precise. A friend of mine recently told me of 3D printing and I am hoping that you guys here can help me determine if this would be the best way for me to create a perfect product.

    I would be designing the product in PRO Engineer software and then using the actual piece here as an internal mold.

    Here are some photos I have of the process so far so that you can get the idea of what I am trying to accomplish. I am working out some kinks in my original design and also making progress in regards to obtaining an optimal finish in my composites fabrication. That said, I still have some work to do in turning out a perfect finish so let's not focus on that, but i regards to creating the perfect mold, please advise. I am investing quite a bit of time and certainly a brake duct does not need to be 100% perfect in regards to its aerodynamic efficiency nor its aesthetic features. But if it can at the product of me furthering my CAD abilities then I am all for it.

    Also, I am aware that in the world of one-off production this is not likely the most cost effective. I am working to develop these pieces to be something that it is marketable, among other pieces swimming in my brain.


    Original foam prototype versus polished mold ready for use.

    Ready for duty.

  2. rawkstar320
    rawkstar320 New Member
    3D printing MAY be an option, but I personally would look into CNC machining. Im not sure what school you go to, but I know at my school we have a Manufacturing Program and sometimes we can get some machine time. (on convince a Mfgt student to get some machine time). Sometimes, they will only ask that you provide your own material.

    If you need any help modeling some parts, my major is Product Design and we use ProE.

  3. JoshJenny
    JoshJenny New Member
    Thanks for the input Jake. I work at a place that restores vintage european race cars ( where we are very well equipped with machinery, but unfortunately it is all of a manual nature.

    I do have a good connection to a CNC machine, which I will have to pay for, but that is fine. I am afraid that with that the costs will be astronomical just in regard to getting a piece of aluminum (assumedly, although I guess maybe a plastic would be an option?) that size.

    3D printing was seemingly enticing in that it only uses the material that it needs.

    Is it safe to say that for the most part, the drawing that I create can be used to quote efforts for both 3D printing and CNC machining?

    I will certainly direct any questions I may have in regards to the drawing aspects of things. I am a motivated novice to Pro/E and have made some cool things, but this creation will be a face melter for me I am sure.

    Thanks for your input!
  4. rawkstar320
    rawkstar320 New Member
    Most companies should be able to use your 3D model for quoting. Some machining facilities do prefer a 2D Engineering Detailed Drawing though.

    If you draw up that part, Try uploading it to FirstCut.Com. They do CNC prototypes and may be able to get you a pretty good price. It would at least give you a reference to use later on.
  5. GlenG
    GlenG New Member
    Hi Josh,
    I'm not sure you got my PM? There are online CNC services out there, you might pay more for run time but their material charges are reasonable because they stock billets by the ton. Bottom line: none of this RP stuff comes cheaply unless you can consider time as money.

    Check out this material: ard_MDS.pdf

    RenShape is a polyurethane foam board. It comes in differing densities. It is NOTHING like blue foam. The higher densities carve or machine like soap! Can take fine detail and is extremely durable! You would need to check to see if it is compatible with the resins you are using. Not cheap, but probably less than aluminum for a given volume of material. For clever hands, this material is a designers dream.

  6. rawkstar320
    rawkstar320 New Member
    @GlenG Ive used foam like that in my Mold Making class, its pretty cool stuff!