Mold making and casting of small plastic camera parts

Discussion in 'Camera Building, Repairs & Modification' started by Denverdad, Sep 13, 2010.

  1. Denverdad

    Denverdad Subscriber

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    Hello fellow fabricators! Do any of you have experience making molds and casting small parts for cameras? I don't remember exactly where I got this idea from or how I latched onto it, but after a little bit of research I have started to think that this might actually be a fun and "doable" way to fabricate certain small parts for the camera projects I always seem to be working on.

    Apparently people do this sort of thing all the time for a variety of other hobbies, and the supplies seem to be readily available. And, the videos and other tutorials I have seen certainly make it LOOK easy! (Haha, yeah we'll see, right?)

    In particular, I am wondering if there is a casting material which works especially well for this kind of thing - something that once hardened is suitably rigid and durable? (and can be made black too, if possible?)

    Sorry if this has been covered before, but I couldn't find much in the forum.

    Thanks,

    Jeff
     
  2. paul_c5x4

    paul_c5x4 Subscriber

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    The black plastic film canisters are often shredded and reused by the diy injection mold guys. I have seen the home built rigs, and it does look easy, but the devil is in the detail.

    If you don't have access to a well equipped engineering workshop, then it is going to be difficult to produce the equipment or the molds - If you had the gear, most of the time it would be quicker & easier to machine from a solid lump rather than make a mold.

    There is also a range of casting resins available, but I've only used the stuff on large projects with glass/carbon fibre mixed in.
     
  3. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    Jeff ,

    You can produce your parts from metal or plastic.

    You have to define that will you copy a camera part or will you create everything from zero.

    What would be the size of the parts , will there be screws on it. What would be the precision ? Where will they be used ? How will they be used , will there be a load , how many times they will be used ?

    If your parts is less than 3 cms , 1.5 inch , there is a company who prints steel powders with a inkjet printer and sinter. They can produce ten thousands of parts daily. This is called Rapid Production.

    If your parts are bigger than this , you can order from shapeways com , metal or plastic. They use steel powder again , sinter and fill the gaps with copper.

    Or you can order a metal or plastic part from CNC shop.

    As you can see , there are many metal parts production methods. You will need a computer drawing and your part can be draw at a cnc shop .

    you can produce it at CNC shop with highest precision and widest range of materials . But this is not cheap.

    Other method is to produce your part with rapid prototyping. But this is not extremelly strong or precise.
    Only you have to do is to ask your CAD guy to record you a SLA , epoxy layer creation with laser technology file. More layer , more precision , more trouble for your wallet.

    If you want a mold and cast your part , you can order from CNC or RP. You can order cnc plastic mold.

    If you have the original part , you can order a mold from it with silicon plastic.

    Carbon powder added epoxy is good contender for your business.

    BUT polymers tends to strech in the mold when they hardens and this must be calculated.

    Silicon polymer mold , if it is hard enough can produce 1000 parts. But final part will be little bit smaller than the original .

    Polymer streches , thats why they use injection molding. Tons of pressure

    Best way to invest in small lathe.

    Its 6 AM , I did not sleep yet ,..
     
  4. Mark Fisher

    Mark Fisher Subscriber

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    We do a lot of modelmaking at work. Cast urethanes are very common and work fine. That said, you have to paint it. UV degrades it terribly. For small, functional parts, I'd recommend machining, laser or water jet cutting. If you are thinking alluminum or brass, I have no idea :smile:
     
  5. dracblau

    dracblau Member

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    Hello Jeff,

    It's not as difficult as some people may think. I've cast parts in resin before using silicone molds (Model car parts). Depending on what you are planning on casting, resins or low temperature metals could work out great.

    Here is a link to Smooth-On and their line of resins: http://www.smooth-on.com/Urethane-Plastic-a/c5/index.html

    A glance at the list shows us a black casting resin, a semi-rigid impact resistant resin, and performance casting resins. These would be good for things such as knobs or even camera bodies if that is your thing.

    For molds, silicone is your best bet for durability and high temperatures if you were to choose to cast items in resin or low temp casting metals.

    Here is a link for Smooth-On silicone rubber: http://www.smooth-on.com/Silicone-Rubber-an/c2/index.html

    I actually haven't used Smooth-On products but have heard good things about them.

    What were you thinking of casting?

    Alex
     
  6. RalphLambrecht

    RalphLambrecht Subscriber

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  7. Denverdad

    Denverdad Subscriber

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    Thanks for all the responses. It is actually the kind of casting that Alex (dracblau) referred to above that is exactly what I had in mind! As a matter of fact, Smooth-On is one of the vendors I ran across in my earlier searching (along with others). I will have to look at their website more closely but it sounds like I should be able to find some type of resin to do the job, with silicone rubber recommended for molds.

    The kind of casting I am talking would preferably start with an existing part. And, as a matter of fact something like a plastic winding knob is actually a good example. The plastic piece shown below is another example (extra credit if you know what camera it comes from!). It is kind of a long story to explain exactly what I want to do with it, but in short I want to make a piece which basically duplicates the lower portion of it (not the "gear" part).

    Jeff
     

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  8. michaelbsc

    michaelbsc Member

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    I haven't done anything yet, but I've actually been thinking to myself, and discussing with my wife, that we can probably make various do-dads that we need using nothing much more than the kitchen stove as a heat source for molding.

    I'm pretty interested in this, but I've been searching mechanical websites, not photo sites!
     
  9. mike c

    mike c Subscriber

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    When I was building models (plastic) the process that Ralph mentioned was just appearing on the market and had a lot of potential in the scratch model building market.Don't know if it durable enough for a the project you have in mind.
     
  10. AgX

    AgX Member

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    Jeff, that very part you are showing could quite easily done witout CAD/CAM from Aluminium just by turning the cylindrical part on the lath, slitting it on a mill and inserting a cut or milled part.
    Fix the latter by bolting or by epoxy-cementing and curing.
     
  11. Denverdad

    Denverdad Subscriber

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    Thanks AgX. I appreciate that it could be done that way but for several reasons it is not what I am interested in. For one I don't have a lathe. And as I indicated before I was really only interested in creating a small part which duplicated the tip of that piece. Lastly I really wanted a plastic piece. That is more in character with the cheap and/or old cameras that I seem to be obsessed with these days. :smile: