Composites Materials for Machine Tools

If you mean perspex, that is not a composite. It is acrylic which is a single homogeneous material.

Composites are combinations of materials which, when used in concert with each other, yield a strong lightweight material. There are many combinations of composites available.

Go to Wiki and do some elemental research. Come back if you have questions.

I suspect you are going to have a hard search to find credible numerical damping data for any materials. Sounds to me like the essence of your project will be to develop the data yourself from some actual material testing. I'm not sure how you would go about doing this without availability of some fairly expensive equipment. Maybe some others in CR-4 have had relevant experience they can share.

Ed Weldon

Hello banukiran,

I think you need to explore the properties of solids. Friction, stretch, springiness and stiffness, hardness, are all things you can make use of. Perhaps you should also think of neoprene as the contact material holding the work piece?

You may also try using air-beds and vacuums, and automatic air control as well as the physical structure and properties of the Composites you use.

Good luck and please keep in touch.

1. 
   
2. FearOfPhysics.com: What is Friction?Friction is the "evil" of all motion. No matter which direction something moves in, friction pulls it the other way. Move something left, friction pulls ...
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1. Friction - Wikipedia, the free encyclopediaW is the force of weight, N is the normal force, F is an applied force of unidentified type, and Ff is the force of kinetic friction which is equal to the ...
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Take care.

"can anyone help me which type of materials can be used for this purpose which are similar to Perpex and how can I know about various materials that can be used for work holding device as the composites."

Isn't this the whole purpose of your "project"? You'll have to test and try to find out what works and what doesn't. You'll have to find a way to test, qualify and quantify different material's damping characteristic and decide which one is usable.

If you want cheap composites, start with phenolic or fiberglass. Should you want to go a little more high tech, try a glass-filled nylon, though I'm not sure that this will satisfy the definition of a composite in that there is no layering.

As previously stated, perspex is an acrylic. My experience with these is that when used with something substantially harder, it becomes grooved under pressure of sharp edges and will peen like a rivet (mushroom) over time under broadly applied loads. These "soft" properties will allow it to hold harder objects in place under less pressure, but at the expense of fixture life.

Regardless of what you choose to use, if you need to work the material, be sure to wear a particle mask while working it.

Thank you sir for your information which was very helpful to me.

I have seen carbon fiber used on portions of machines; one was an inspection machine (Co-ordinate Measuring Machine) and on the gantry portion of a Cutter for composites.

Here's a link to composite cutter company:

http://www.agfm.com/

Not much real info there, but perhaps they can lead you to a contact or studies on this subject.

Their parent company is in Austria, here's their link:

http://www.gfm.at/

Good Luck!

The phrase "damping factor" deserves your attention and research.

Here is a good starting point:

http://en.wikipedia.org/wiki/Epoxy_granite

Mark Bingham
Relativity PL

Thank you sir for your reply. I have studied about that material in which it has been said that it is best suited for Machine tool base and is replacing cast iron and steel. can i use epoxy_granite material for work holding device during milling operation Whether it is suitable or not

Hello banukiran,

You say "can i use epoxy_granite material for work holding device during milling operation Whether it is suitable or not".

I am not sure if this is a question or a statement?

However, for the milling operating it is crucial to have the piece held dead still and tight with no movement whatsoever. The last piece of your 'statement' says "Whether it is suitable or not". ..................... >>>

This is not the way to decide whether or not a substance and method is correct and right and SUITABLE is the criteria to use surely?

I mean you may just as well use the 'play putty' "Plasticine", which definitely is NOT suitable. I have to say your attitude, despite asking and getting so good advice sticks and, it certainly not the way to work to find the correct composite substance for any particular type of work.

I am very disappointed. You have clearly not taken to heart any of the advice given.

This is my personal opinion and I refer to the method used only and, do not intend any insult to you personally.

Take care, and...................................LISTEN TO OTHERS WITH EXPERIENCE!

Dear Banukiran,

Epoxy_granite (speaking generically of composite materials for machine tool construction) adds mass with high capacity to dampen vibrations. It does not have excellent tensile properties, so I have not seen it applied often in work-holding fixtures. These are often highly tensile stressed, while epoxy_granite excels in compression.

Epoxy_granite often is cast around a welded steel armature which embodies the critical attachment points such as threaded inserts and dowels, jigged to perfect position before the composite material is cast.

Each part of your design has a different task to perform: the armature may provide a steel "spine" and the attachment points, while the surrounding large body of epoxy_granite may provide mass, some stiffness from its generous dimension, good compressive performance and all of the damping capability.

The machine-tool industry grew and flourished thanks to the high damping factor of cast iron. Epoxy_granite shifts this special property away from the iron foundry, into the polymer casting shop.

There are useful threads at www.cnczone.com if you search on "epoxy granite".

Mark Bingham
Relativity PL

Are you are asking if someone can give you some ideas of non metallic materials (other than the material you spoke of) that are used for making holding devises for milling machines? If you asking for test data of the materials holding strength as well then you probably won't get far with that request. If I am correct then you must already have access to the equipment to test the material as well as an idea of how to do it. I have a very good friend that is working on something similar and has already done some test trials on different materials. I am sure he will not give you the results of his tests because it is his business but he may be willing to at least give you some ideas on materials to start with. If I can get any ideas from him I will let you know.