×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Machine to make Bath Bombs

Machine to make Bath Bombs

Machine to make Bath Bombs

(OP)
I have recently been asked to design and make a machine for the production of “Bath Bombs”.  These are perfumed foaming blocks that are used in spas and baths.

The ingredients (consisting mainly of Epsom salts) are mixed dry and a very small amount of water is added.  They can be pressed into the mould by hand (i.e. exerting approximately 10 psi).  The machine is to press them directly into the mould, where they can be de-moulded almost immediately and the hopper needs to hold sufficient for 100 units (about 500 cubic inches).

Because of the dry nature of the material, it will not flow and compressing it, hardens it.  It is similar in nature (but much finer) to the dry mix used to make concrete slabs.  An Auger feed could be used, but my client would prefer a cheaper and easer to clean, design.

I am open to all suggestions.

Tony

RE: Machine to make Bath Bombs

Trust me, it will flow. Track down some people in powdered metal I am sure they can assist you with hopper and shoe concepts.

You can probably do this easily with a compacting press or a machine based on a similar concept.  You premix the powders in the appropriate mixture then drop it into a hopper which gets placed on a stand above the machine.  Use gravity to feed the powder down to a shoe.  Let the machine do the rest.  Given the forces you can probably get 20 strokes per minute easily.

RE: Machine to make Bath Bombs

Vibratory hopper? usually prevents powders & fine mixes from 'bridging'

Good Luck
johnwm

RE: Machine to make Bath Bombs

There are small air operated vibrators for such applications.  They are ususally mounted on the cone area and are fairly inexpensive.
McMaster Carr carries them.

Griffy

RE: Machine to make Bath Bombs

Actually not vibratory.  Does not work as well.  

As I mentioned, talk to someone with more experience in Powedered Metal than myself (only 4 years) and I am sure they will have lots of insight.

RE: Machine to make Bath Bombs

A small amount of water would then make it a mastic?. Pump it with a peristaltic.

RE: Machine to make Bath Bombs

I would add the water down at the die cavity instead of in the hopper.

RE: Machine to make Bath Bombs

(OP)
Thank you all for your interesting insights, specially adding the water last.

Tony

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources