Recent Content by Rotarysmp

  1. Rotarysmp
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    Resin Bound Core

    Well put. Simple green sand, and cores bound with sugar water or NaSi can take you a very long way.
    Post by: Rotarysmp, Jun 22, 2025 in forum: Sand Casting
  2. Rotarysmp
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    More Boss 429 Intake Manifolds

    Thanks for the foam feedback. What is your heat treatment schedule please Kelly?
    Post by: Rotarysmp, Jun 22, 2025 in forum: Lost foam casting
  3. Rotarysmp
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    Cast iron?

    Good one Jeff, I have learnt not to pour iron until it is hot enough for sparks to be coming off the surface of the melt. I use the same size...
    Post by: Rotarysmp, Jun 20, 2025 in forum: Sand Casting
  4. Rotarysmp
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    More Boss 429 Intake Manifolds

    Hi Kelly, Looking great. Any technical reason for the pink v green foams? Mark
    Post by: Rotarysmp, Jun 3, 2025 in forum: Lost foam casting
  5. Rotarysmp
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    1920 Redrup Radial - replica motorcycle engine

    Here is my video on the production casting and machining... of scrap!!! Grrr. [MEDIA] Cheers, Mark
    Post by: Rotarysmp, Jun 1, 2025 in forum: Model engines
  6. Rotarysmp
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    1920 Redrup Radial - replica motorcycle engine

    A more productive casting session yesterday evening. Since I already had one green sand and two petrobond heads cast, I made up to two sets of PB...
    Post by: Rotarysmp, May 28, 2025 in forum: Model engines
  7. Rotarysmp
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    1920 Redrup Radial - replica motorcycle engine

    I only got one melt poured yesterday, and then two thunderstorms passed through and it hosed down. Martin pointed out that the head in my video...
    Post by: Rotarysmp, May 27, 2025 in forum: Model engines
  8. Rotarysmp
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    Please post pics/vids of your current mullers

    My muller is covered in this video... from 7:33. It is only 370W, so it cant do too much sand at once, but will do one of my standard sized flasks...
    Post by: Rotarysmp, May 26, 2025 in forum: Sand Mullers
  9. Rotarysmp
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    1920 Redrup Radial - replica motorcycle engine

    Thanks. Do you print your patterns 0.4mm smaller?
    Post by: Rotarysmp, May 25, 2025 in forum: Model engines
  10. Rotarysmp
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    1920 Redrup Radial - replica motorcycle engine

    It seems to work fine on PLA, PET-G and ASA. How much thickness does your epoxy dip add?
    Post by: Rotarysmp, May 25, 2025 in forum: Model engines
  11. Rotarysmp
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    1920 Redrup Radial - replica motorcycle engine

    Here is the video of the prototyping. Not sure why I had such a brain fade and thought the casting temp should be 600, and then 680°C. [MEDIA]
    Post by: Rotarysmp, May 25, 2025 in forum: Model engines
  12. Rotarysmp
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    1920 Redrup Radial - replica motorcycle engine

    Yeah, I did two from that crucible, and the second one to pour also failed to fill the fin completely, so 700° must be right on the edge for this...
    Post by: Rotarysmp, May 23, 2025 in forum: Model engines
  13. Rotarysmp
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    1920 Redrup Radial - replica motorcycle engine

    My heat control is improving. The first two photos are of a head poured at 680°C. Very nearly filled. I had a couple of sand defects pulling the...
    Post by: Rotarysmp, May 23, 2025 in forum: Model engines
  14. Rotarysmp
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    1920 Redrup Radial - replica motorcycle engine

    Thanks Kelly. I hope so.
    Post by: Rotarysmp, May 20, 2025 in forum: Model engines
  15. Rotarysmp
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    1920 Redrup Radial - replica motorcycle engine

    On to the next part. The cylinder head. [ATTACH] The Redrup radial is a side valve engine, so the head is a simple lid, with a spark plug in it....
    Post by: Rotarysmp, May 19, 2025 in forum: Model engines