Free 186 More Best Homemade Tools eBook:  
Get 2,000+ tool plans, full site access, and more.

User Tag List

Results 1 to 8 of 8

Thread: Spinning metal - searching info advice

  1. #1
    Supporting Member rendoman's Avatar
    Join Date
    Nov 2015
    Location
    Italy
    Posts
    435
    Thanks
    451
    Thanked 495 Times in 241 Posts

    rendoman's Tools

    Spinning metal - searching info advice

    Hi all!
    One of my future project will be a sort of horn (5" diameter mouth, 1" throat, aprox lenght 5") for a couple of planar speaker mid-tweeter.
    I'm thinking about other ways to do the job. I would avoid machining from aluminum, wood would be maybe better.
    I remember some old YouTube videos about metal spinning with normal "home size" lathes, it seems possible with few tools and a good mold. I have no experience in this field, do you think could it be possible to have a nice internal surface with aluminum (2mm or close)
    Any advice welcome
    thanks!

    186 More Best Homemade Tools eBook

  2. #2
    Supporting Member Frank S's Avatar
    Join Date
    Aug 2015
    Location
    Peacock TX
    Posts
    11,172
    Thanks
    1,970
    Thanked 8,760 Times in 4,192 Posts

    Frank S's Tools
    It should be possible. I've done some spinning a long time ago. I don't remember ever trying to do anything with quite that small of throat though.
    What I think I would do would be to make my mold then start out with a small sacrificial disk say 3" in diameter see how it turned out You can always make a small funnel out of it later. Then go to a larger disk say 4" take note of how much further up the mold the disk wound up and go from there by the time you are ready to make the actual part you will have a fair understanding of how to do it.
    On thing don't try to achieve the final shape in only a single push up the mold. Work a small short distance up the mold from the throat then run your spoon across the face all the way to the outer rim each time you push a litter further up the mold the metal needs to be allowed to flow fluidly as you work it into the final shape taking care not to try and take too large of a push at a time to prevent the edged from wobbling fiercely. Be mindful that you are forcing the metal to stretch and shrink at the same time. Once you have your completed shape simply part off the excess .

    2000 Tool Plans
    Never try to tell me it can't be done
    When I have to paint I use KBS products

  3. The Following User Says Thank You to Frank S For This Useful Post:

    rendoman (Oct 22, 2019)

  4. #3
    Supporting Member rendoman's Avatar
    Join Date
    Nov 2015
    Location
    Italy
    Posts
    435
    Thanks
    451
    Thanked 495 Times in 241 Posts

    rendoman's Tools
    Thanks for the advices!
    I'm thinking about other ways to build an horn, not an easy task considering the shape

  5. #4
    Supporting Member thehomeengineer's Avatar
    Join Date
    Nov 2017
    Location
    Berkshire UK
    Posts
    704
    Thanks
    720
    Thanked 2,050 Times in 405 Posts

    thehomeengineer's Tools
    Hi rendoman
    I have spun several items for my steam engines mainly brass copper and steel. I will post the tool I made to fit in a standard lathe tool holder on my Colchester student lathe. 2 mm Aluminium is quite thick for a manual lathe to spin and I would be tempted to anneal before spinning. (I hope I am not telling you how to suck eggs) To anneal the aluminium you simply rub hand soap over the aluminium and heat until the soap on the surface goes black leave to cool and the aluminium will flow a lot easier. This may have to be repeated as the aluminium work hardens during the process and if not annealed potentially could crack. You will know when it has work hardened as the spinning will not flow as easy. This is only my opinion and I am sure there are more qualified people in this subject than me, but without giving it ago you will never know.
    I will post tool later.
    The Home Engineer

  6. The Following User Says Thank You to thehomeengineer For This Useful Post:

    rendoman (Oct 22, 2019)

  7. #5
    Supporting Member jdurand's Avatar
    Join Date
    May 2019
    Location
    Krasnodar Krai, Russian Federation
    Posts
    1,456
    Thanks
    126
    Thanked 742 Times in 416 Posts

    jdurand's Tools
    I did some on my mini lathe but not that bit. I needed to reduce the end part of a coper pipe to an accurate size. Worked fine.

  8. The Following User Says Thank You to jdurand For This Useful Post:

    rendoman (Oct 22, 2019)

  9. #6
    Supporting Member rendoman's Avatar
    Join Date
    Nov 2015
    Location
    Italy
    Posts
    435
    Thanks
    451
    Thanked 495 Times in 241 Posts

    rendoman's Tools
    Thank you for advices! It seems not an easy job to do, I havn't considered the possibililty to break the aluminum. I'm curious to see your tools and setup also!
    I'm thinking about using plaster for a prototype, having a couple of horn finished and polished it would make a good mold (and a new polishing for sure). I'm so undecided about.

    The big horn is the object I would like to duplicate
    Spinning metal - searching info advice-68612324_10219524588048037_3001979043785474048_o.jpg

  10. #7
    Supporting Member thehomeengineer's Avatar
    Join Date
    Nov 2017
    Location
    Berkshire UK
    Posts
    704
    Thanks
    720
    Thanked 2,050 Times in 405 Posts

    thehomeengineer's Tools
    Link to spinning tools I made to manufacture bits for my steam engines
    spinning tools
    The Home Engineer

  11. The Following 2 Users Say Thank You to thehomeengineer For This Useful Post:

    baja (Oct 27, 2019), rendoman (Oct 23, 2019)

  12. #8
    Supporting Member rendoman's Avatar
    Join Date
    Nov 2015
    Location
    Italy
    Posts
    435
    Thanks
    451
    Thanked 495 Times in 241 Posts

    rendoman's Tools
    Thank you!!



    186 More Best Homemade Tools eBook

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •