Silicone Mould Vulcaniser

Discussion in 'Tools' started by Toto, Jul 9, 2019.

  1. Toto

    Toto I'm best ignored Staff Member Founder Administrator

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    I decided it was time to grow a set of gonads, took the plunge and bought myself a vulcanising can. I can see myself going through a few sets of low temperature silicone moulds and whilst I'm quite happy to outsource this in the short term, I'd rather be attempting my own in the longer term.

    To give an idea, to have 1 x 9" mould made is £90.00 plus vat and then the cost of white metal on top of that. The average loco kit will require 3 or 4 and on the odd occasion..... more in order to produce all the required castings. Not cheap. So ...... maybe by ths end of the week, I should have it delivered.it wont see action u til I come back from Cyprus then I'll give it a bash. I mean ...... what could possibly go wrong. :avatar:
     
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  2. Toto

    Toto I'm best ignored Staff Member Founder Administrator

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    and its been delivered and here are the photos .....


    The vulcaniser itself .....


    and with the lid off .........


    shim plates for packing out the moulds for added pressure if its needed for moulding smaller parts .....


    central mould former ..........


    some mould sculpting tools .........


    more sculpting tools and a retractable scalpel ......


    mould studs to create the mould registration .......


    Low temperature silicone mould discs ......


    a couple of organic rubber moulds for production moulds ( rather than master moulds ) should I wish. These cook at 180 degrees as opposed to 90 degrees of the low temperature silicone.


    a box full of low temperature silicone moulds. I have around twenty sets ( pairs ) of moulding discs in stock with which to get started. Only two sets of organic rubber and 18 or so low temperature silicone.

    I'm hoping to use the four days at home on return from Cyprus with which to have a go at my first mould. Fingers crossed.

    cheers for now

    toto
     
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  3. Toto

    Toto I'm best ignored Staff Member Founder Administrator

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    A little bit more on the production versus master moulds idea.

    The master moulds will use resin printed masters to produce the initial prototype parts which are " cooked " at 90 degrees in the low temperature silicone rubber discs. Then , if I wish, I could take one of the white metal parts spun from the silicone mould and create a " production " mould in organic rubber.

    I could not use the printed resin masters to create an organic rubber mould as the 180 degrees needed to " cook " it would melt / destroy the resin master.

    This way, I would keep the Low temp silicone moulds purely as " the master copy " from which to produce production copies.

    The organic discs are cheaper but dont have the same life span.

    It all reallt depends on what you think the life span of the kits will; be and how many you are likely to produce over time. Also, If I decided to sell the range on at some time in the future, I would have a nice new set of master moulds to pass on to the new owner rather than passing on tired moulds.

    It is obviously a little more expensive at the start to produce two sets of moulds straight off but will pay in the long run otherwise if the moulds need renewed, you would be back to square one creating brand new moulds from printed resin.

    We'll see how it goes going forward ..... its a question of available budget at the early stages of the development / venture.

    cheers

    toto
     
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  4. gormo

    gormo Staff Member Administrator

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    Very industrial Toto,
    Your back shed will be soon classified as an industrial precinct......I hope this activity does not disturb your neighbors.??
    Are there noise or smell issues associated with what you`re doing.???
    Then again a bit of bribery would not go astray if there were issues.......you know ......a bottle of the best brown highland water for your neighbors could work wonders.
    :avatar::avatar::avatar::avatar:
    Seriously though Toto......good on you for having a go.........:thumbs::thumbs::thumbs::thumbs::thumbs:
    :cheers::tophat:Gormo
     
  5. ianvolvo46

    ianvolvo46 Staff Member Moderator

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    :faint:wow full on stuff Toto … enjoy Cyprus :cheers:

    Ian vt
     
  6. Toto

    Toto I'm best ignored Staff Member Founder Administrator

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    Yes .... I'm keen to see the results from the vulcaniser can. I'll be starting off with some of the simpler, flatter parts just to get the process right without having to be concerned with worrying about under cuts etc that some of the more complicated parts need. I'm confident that I can do a decent job of it. It will be another part of the jigsaw in place.

    I'll post up some photos of the various stages when it happens. I'm off to look for an industrial worktop oven to fit in the shed.

    Cheers for now.

    Toto
     
  7. Keith M

    Keith M Staff Member Moderator

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    ......and that's the crux of it Toto, having the confidence to jump in and give it your best shot despite not having experience. That's really the only way to actually get experience, a bit like actually building models, 'cos nobody had experience before they had a go for themselves. As Gormo said, good on you for having a go.:thumbup::thumbup::thumbup:

    Keith.
     
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  8. Toto

    Toto I'm best ignored Staff Member Founder Administrator

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    I have to Keith as out sourcing can cost the earth if you are trying to introduce a complete range and accessories all at once. Not so bad if you have an established range where the moulds exist and the cost is historical.

    I could have up to 4 or 5 moulds per loco and that is just the white metal. The class 26 / 27 bas another 6 moulds on top of that for lost wax brass fittings. So you can imagine the cost of that lot. If I can do my own successfully ( white metal to start with ) I can save thousands of pounds across the whole range. The lost wax will be in the future. I'm happy I have a good source for that at the moment.

    Going forward ( particularly cashflow and a bit time once the initial range is over the line and selling ) I intend to take every aspect of the kit production in house. The only thing that will remain out sourced will be the main brass etches themselves.

    This wont remain a secondary source of employment for long :avatar:. Once I get the initial learning curve over, things will be pushed as hard as I can to take it towards a full time venture.

    Fingers crossed.

    Toto
     
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  9. ianvolvo46

    ianvolvo46 Staff Member Moderator

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    I'll run the Spanish branch … 'Tinto Trains'

    tinto train.jpg
     
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  10. Toto

    Toto I'm best ignored Staff Member Founder Administrator

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    Sounds like a plan Ian. :tophat:
     
  11. Toto

    Toto I'm best ignored Staff Member Founder Administrator

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    Just nipped into the shed between domestic duties and cut out a few 9" mould templates.


    not exactly cylindrical but close enough for what I need.


    Marked out a smaller core circle where the mould core is fitted and another outer circle.

    The space in the middle is the permissable moulding area. There can be a tiny bit flexibility with the outer circle boundary but not the inner. These are recommended boundaries but are best being heeded. Apparently there are optimum limitations that you should stick within where possible in order to get the best results. They could be broached but we would be talking maybe a couple of mm.

    The plywood templates let you play around with the setting out of the parts in order to try and achieve the best balance for the moulds. Trying to keep the mould evenly weighted and the parts spaced out gives the best performance from the mould and the spincaster.

    Once you are happy with the intended layout on the template ( after a bit shuffling around of parts ) you can then commit them to the mould and press into place within the silicone.

    Thats the theory anyway.

    cheers for now

    toto

    Forgot to add, just ordered in the Catering oven ....... anyone for pizza. :avatar:
     
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  12. John Boy

    John Boy Full Member

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    Toto,

    Has the supplier advised you how to store the rubber blanks in order to prolong the shelf life?
    As the rubber is fully compounded with fillers and vulcanising agents the mix will eventually cure at room temperature. So storage in a wooden shed in summer is far from ideal. It may pay to invest in a small refrigerator.
    Best of luck with your project.

    John
     
  13. Toto

    Toto I'm best ignored Staff Member Founder Administrator

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    Hi Johnboy

    Thanks for that. Something I never knew. I had wondered mind you. I'll do a little investigation into the optimum storage temperature in order to get the best environment for them.

    Many thanks for giving me the pointer. :thumbs:
     
  14. paul_l

    paul_l Staff Member Administrator

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    Rough rule of thumb (very rough) - every 10C the temp increases the cure time halves
     
  15. Toto

    Toto I'm best ignored Staff Member Founder Administrator

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    90 degrees but no base point to work out where the starting point is. Apparently 2 hours. So if 100 degrees it would be an hour. However, the recommendation is 90 degrees so 2 hours curing ( or cooking ) it is. Mind and bring plenty masters. :thumbs:
     
  16. Toto

    Toto I'm best ignored Staff Member Founder Administrator

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    Well ...... here are the first results from the vulcaniser .....


    Took the can ages to cool down prior to being able to take the moulds out .....


    then the mould halves needed to be separated ....


    and now they need the gates and vents cut into them before being able to give them their first test spin.

    The moulds are still luke warm so I'll let them fully cool down before gating and venting.

    They look like they should give a decent result for my first attempt.

    more later.

    cheers

    toto
     
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  17. SBt

    SBt Full Member

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    Am watching with great interest.
     
  18. York Paul

    York Paul Staff Member Moderator

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    I can see a couple of radiator fans, some air tanks and the radiator matrix... I need to clear my bench in readiness me thinks:avatar:
     
  19. Toto

    Toto I'm best ignored Staff Member Founder Administrator

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    The longest part of the process is the cooling and separating part which takes a good four to five hours. You cant rush it without the risk of damaging the mould. So id say two moulds max per day could be achieved with it. I could get another on whilst I gate and vent the initial one. Quite happy with it so far though.

    cheers

    Toto
     
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  20. paul_l

    paul_l Staff Member Administrator

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    I'll look out the stl's to reprint the 26 / 27 parts for you to do next.

    Anu preference on which first ?

    Paul
     

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