Home Forums Everything about the Mini Tricopter Project: 6" Ducted props (WIP)

This topic contains 35 replies, has 4 voices, and was last updated by  Kevin_Erik 3 weeks, 5 days ago.

Viewing 6 posts - 31 through 36 (of 36 total)
  • Author
    Posts
  • #40505

    Kevin_Erik
    Moderator

    Be aware that a 5 inch prop is 128 mm across so any duct made will be 160 mm across. This includes the duct wall and the duct aero-lip. Below is a photo from my Excel spreadsheet. Obviously you can make one with a smaller lip but most of the lift would be lost.

    #40510

    MadPoet
    Participant

    Thanks Kevin! Well that’s me out then. Good luck with the project!

    #40513

    Kevin_Erik
    Moderator

    You could alway contract a print house to make one for you… With ABS / PLA the cost is about $10 per duct.

    Thus far thats what I’ve done as the cost for a printer cant be justified.

    #40820

    Kevin_Erik
    Moderator

    Would never be able to justify the cost to my wife.

    #64574

    punong_bisyonaryo
    Participant

    Is the 6″ duct project still alive?

    #64577

    Kevin_Erik
    Moderator

    I did design a pair but never printed it.

    Consider that a 5” set i had made from SLI Nylon was really $$$. Worse yet, the prints were about 40 grams each. Scale this up to a 6” design and the mass would easily be 60 grams per duct! Sure i could of made them lighter but they’d break from the slightest impact. The resulting duct-wall collision with the propeller would cause the propeller to implode. Thus the copter would fall and crash badly, wrecking the other Ducts in the process.

    Now consider a 3” duct has about 8-15 grams and you’ll soon realize that this doesn’t scale up well with the copter size.

    My conclusion: Prop-Guards are better than Ducts.

    Justification(s)
    -Lighter in many cases, 50%
    So.
    -Much cheeper to print.
    -Less complex
    -Can still reduce prop-tip vortices if designed right.

Viewing 6 posts - 31 through 36 (of 36 total)

You must be logged in to reply to this topic.