Deburr Aluminum but No Tumbling or Abrasive?

A. I read your letter in finishing.com. I would like to introduce you to our process, but I also would need more information from you regarding the size of the burrs. Our company has a process originally developed out of Sandia National Labs that uses a rapidly pulsed high energy ion beam to modify surfaces on materials. This ion beam, IBEST, melts the surface to a 2-10 micron depth at a pulse per second. The material then rapidly cools, freezing the near surface at a billion degrees per second. This creates a surface which varies according to material properties that is smoother, refines grain size, removes burrs, hardens, and various other effects in tool materials; this increases the performance of many tool steels and cemented carbide materials This depends on how the customer wants the results to turn out in the end, but I think that we would successfully remove your burrs created without changing the surface tolerance of the part.

Sincerely,

A. Dick,

You might look into thermal (flash) deburring. This technique uses an ignition front to melt, oxidize and vaporize burrs.

A. There are a couple of alternatives you can try:
- Depending on the alloy of aluminum, using an aluminum etchant to remove burrs might be feasible. - A proprietary chemical bright dip would give you a micro-etch with controlled surface removal.

Do you have the facilities to do something like this in house ? i.e., finishing line w/appropriate waste treatment? If not, a qualified aluminum/anodizing job shop probably would be a good idea.

By tumbling, I'm assuming vibratory finishing. With the right media, and the right compound combination, you can accomplish deburring, and brightening as well (this would be a more economical alternative if you have the equipment available or also a local job-shop to provide this service.)

Good luck, I hope I have been of some help to you.

Sincerely,

A. Dick:

You might consider using electropolishing for this application. We have had some excellent results on certain disk drive parts.

adv.
Please call us.

Regards,

A. We have experience with several applications very similar to the one you described. One recent application was for the deburring of an aluminum diecasting. The part was a computer guide arm (fixed magnetic disc). The best way to investigate whether a mechanical processes would work for you is to have samples processed. The mechanical equipment we test in (vibratory, high energy disk and barrels) is usually the most economical alternative if a successful process can be developed. Often a simple change in tumbling or blast media can give you the answers you are looking for.

A. Dick:

The 1st assumption here is that your tumbling is vibratory finishing. The 2nd assumption is that the actuators can be successfully handled by standard vibratory equipment types (bowl or tub). That you do not have nesting problems where the parts will stick together during processing. The 3rd assumption is that there is a media available with the correct shape and size to deburr the Aluminum actuators.

If you have the correct vibratory equipment to handle the actuators, I suggest you might consider using a liquid compound that chemically accelerates burr removal and surface refinement. This can be 3-4 times faster than conventional processes. The media selection for chemically accelerated processes is usually non or low abrasive content plastic or ceramic media. These medias have extremely low attrition rates and as such hold their geometry for a very long time.

Regards,
Bill

A. Dick,

If I understand the part and problem, you probably are on the right track with tumbling (i.e., vibratory, tumble barrels or another mass finishing operation). What you need is a fresh set of eyes on the situation. Your best bet is (if you haven't already done so) to get a hold of you local metal finishing rep - look in the phone book under "Metal Finishing - Equipment and Supplies". They can come in, look at your problem and suggest several possible solutions. Also, get some sample parts to that person and/or the manufacturer(s) they recommend. The sheer volume of possible combinations of media, chemistry, machinery and processes is mind-numbing, so let someone else (who may already have experience with a part like yours) do the heavy lifting.

A. There are several ways to remove burrs from aluminum part; however, the best methods for casting or machining parts is to use a deburring rotated drum with abrasive media (mostly use composite or other plastic intermediate material mixed with water).

Another way is to use a deburring machine using scotch bidirectional. Anyway, both methods are commonly used in aerospace plants. Good luck....

A. Deburring small or delicate parts such as you seem to describe are usually now performed in compact centrifugal finishing systems. These types of systems usually employ media that is quite small and can access the finer features of smaller parts such as yours.

Additionally, dry process media with micro-fine abrasive materials can be utilized to develop surface finishes that rival that on jewelry parts, if functional requirements should call for it.

A. Previous comments are all good. However, what is your volume of production, what surface finish is required, and is cost a factor. What equipment do you have in house, or do you need equipment? Need more information to properly direct you

A. There are about 5 major deburring methods in use. Three involve mechanical processes and abrasives. One involves the use of temperature and the other is chemical. Each system has advantages and disadvantages. Rather than to go into details and/or advantages of each one, I suggest you refine your question either to the immediate problem or what you want to accomplish.

A. I cannot answer your question regarding a chemical method of working your parts; however, there are some other mechanical methods that could be used. Your parts are thin, but not that thin that they couldn't be worked in a mass finishing system using a dry abrasive media. Proper sizing of equipment and the part are important to avoid distortion. If your parts are flat, it might also be possible to do this in a wide belt Timesaver.

A. Electropolishing may easily solve your problem.

A. I recommend the thermal deburring method.
It's a high investment and built for high quantity.
Regards,

Q. (I'm the original poster) I should add that we are eventually going to want to gold plate these aluminum blocks, so while for the initial tests, I'm willing to try anything to de-burr, ultimately the process should leave a surface which is compatible with gold plating.

A. Hi Daniel
Standard chemical polishing processes may work but you will need to experiment.
However, the size and complexity you describe sounds like a difficult milling job or a very simple photo-etching job with no burrs to worry about.
You could even mass produce them as, say,a 10x10 array and slice them after gold plating
You could even consider gold plating through a resist mask and using the gold as the etch resist

? Hi Vinayak. What is the alloy, the fabrication method, and approximate production rate? Why is avoiding this common finishing method important to you, and which (if any) of the above alternatives sound interesting? Thanks.

Regards,