Vacuum pump suggestions


Results 1 to 10 of 10

Thread: Vacuum pump suggestions

  1. #1
    Registered
    Join Date
    Jan 2007
    Location
    germany
    Posts
    18
    Downloads
    0
    Uploads
    0

    Default Vacuum pump suggestions

    Hi all,

    i need a suitable vacuum pump to hold down 3 separate pieces of hardwood with 36x4,5 inches each. Note that each part will have it`s own vacuum fixture and will be rubber sealed so the vacuum force would be more important than the max airflow.

    Cutting depth will be around 1/2 inch max, bit diameter would be between 1/2 and 1 inch max, upcut 2 flute round nose.

    So what kind of a vacuum pump (specs) would you suggest for such an application?

    Thanks very much for any advice.

    Similar Threads:


  2. #2
    Member
    Join Date
    Jul 2005
    Location
    Canada
    Posts
    12177
    Downloads
    0
    Uploads
    0

    Default

    For that area and type of cut you are going to need the maximum holding power possible so your pump will need to be able to pull a vacuum as close to one atmosphere as possible. A good vane pump that can get down to 28 inches of mercury will probably be the best aaproach.

    An open mind is a virtue...so long as all the common sense has not leaked out.


  3. #3
    Registered
    Join Date
    Jan 2007
    Location
    germany
    Posts
    18
    Downloads
    0
    Uploads
    0

    Default

    Thanks Geof, could you give me some specific model recommendations? I´am still pretty unfamiliar with vacuum pumps.



  4. #4
    Member
    Join Date
    Jul 2005
    Location
    Canada
    Posts
    12177
    Downloads
    0
    Uploads
    0

    Default

    Cannot suggest any particular models.

    This link shows the type I think you should be able to find over there:

    http://www.welchvacuum.com/welch_vac...igh/index.html

    An open mind is a virtue...so long as all the common sense has not leaked out.


  5. #5
    Member samu's Avatar
    Join Date
    Feb 2007
    Location
    Canada
    Posts
    314
    Downloads
    0
    Uploads
    0

    Default

    if you just work ocasionally with vacuum fixture and have a good compressed air supply, a venturi could be a good option, look on Mcmaster, there is good venturi pulling out a vacuum about 28" Hg for less than 80$. But it takes a lot of CFM so it's not recommended for continuous use.



  6. #6
    Registered
    Join Date
    Jan 2007
    Location
    germany
    Posts
    18
    Downloads
    0
    Uploads
    0

    Default

    I`ve been doing some calculations and it seems that having well sealed fixtures is more important than the Hg pull but feel free to correct me.

    Formula: Hg x square inch x 0.5 = Overall Lbs

    Part1 (2"x18.5"):
    24Hg Pump: 24x37x0.5= 444Lbs
    28Hg Pump: 28x37x0.5= 518Lbs

    It looks like there isn`t that much of a difference but then again, i have no practical experience with vacuum.

    In any case, i`am still trying to figure out which "cfm/Hg" class pump would be sufficient for my purposes, i don`t want to pay too much for a pump that would practically be overkill for me.
    Just for some clarification, i`ll be cutting parts exclusively held by sealed and custom shaped fixtures, so no leaks during the whole process.
    And the pump has to be able to endure daily usage.

    I figured that 26Hg or more would be fine but what minimum "cfm" would be necessary to hold down 3 parts simulaneousely with 37 square inches each?
    Since i`ll be cutting wood and the fixtures wont be a 100% airtight, the pump has to have a sufficient "cfm" to compensate.

    Thanks again, any help is appreciated.



  7. #7
    Member samu's Avatar
    Join Date
    Feb 2007
    Location
    Canada
    Posts
    314
    Downloads
    0
    Uploads
    0

    Default

    I never test it but I know that you can achieve good result with a old fridge compressor. But dont't forget that wood is a porous material that let pass some air. Especialy if it is mdf.



  8. #8
    Registered
    Join Date
    Oct 2006
    Location
    United States
    Posts
    2
    Downloads
    0
    Uploads
    0

    Default

    Remember that if f you cut a channel for the rubber vacum seal, so the seal will recess and the part will be flush against the holding fixture, i.e., "spoilboard" you will then have to increase the "vacuum surface area" of the parts being held beyond that of the vacuum holes themselves.

    If you peel and stick a thin and narrow gasket to the surface of your fixture you will have the max "VSA" and only have to adjust the Z axis (if even necessary).

    Good Cutting!

    John Murphy
    www.allstaradhesives.com



  9. #9
    Registered
    Join Date
    Jan 2007
    Location
    germany
    Posts
    18
    Downloads
    0
    Uploads
    0

    Default

    Thanks for the tips guys.
    Thanks to the forum I learned a lot about vacuum so I won`t have to do a lot of experimenting.



  10. #10
    Member
    Join Date
    Nov 2010
    Location
    USA
    Posts
    176
    Downloads
    0
    Uploads
    0

    Default Re: Vacuum pump suggestions

    Quote Originally Posted by samu View Post
    if you just work ocasionally with vacuum fixture and have a good compressed air supply, a venturi could be a good option, look on Mcmaster, there is good venturi pulling out a vacuum about 28" Hg for less than 80$. But it takes a lot of CFM so it's not recommended for continuous use.
    This is interesting! I have a rotary screw air compressor, so a constant source of air is not a problem. I will search these forums for more info, as I am going to build a vac table for a 5x10 cnc router table once I figure out the details.



Tags for this Thread

Posting Permissions

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


About CNCzone.com

    We are the largest and most active discussion forum for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

Vacuum pump suggestions

Vacuum pump suggestions