Saturday, February 25, 2012

BLANK!

BLANK!   It is the age old problem.  Well maybe not for everyone.  But certainly for machinists.  Typically,  a machine shop does not know about the availability of a "blank" and will wind up buying a more expensive piece of bar stock instead. 

So, here is the scenario....Machine Shop X gets a print from their customer to make a short run of a part that is made from Sintered Bronze. Usually Machine Shop X will just go out and buy a piece of Sintered Bronze bar stock to make the part.  This is fine, except now you will spend a great deal of money for the part and a whole lot of time in machining.   BLANK!  Here is where the novel idea comes in!  A "blank" already has an ID and an OD and is found in a number of "standard" sizes.  So you choose which blank size is closest to your finished dimensions and then machine. You can add a flange, increase your ID, turn down your OD, groove holes and much more.  You'll still have to do some machining but it will definitely be a lot less work then the bar stock and Machine Shop X will have saved $$.  Cha-Ching!
Til next time..

Good News or....Bad?

Hi All!  I just read this article on Metal Center News and I thought it was very thought provoking.  We shall see what happens in the coming months!

Copper, Brass Shipments Climbing
Copper and brass shipments continued to rally in March. Total shipments were up about 13.6 percent from February 2010 and 14.3 percent over March 2009, according to the Copper and Brass Servicenter Association, Overland Park, Kansas. This trend is in line with what the manufacturing and metals markets are experiencing overall, CBSA reports.

Total copper shipments rose slightly to just under 10 million pounds. Alloy shipments also rose sharply during the month, from just over 12 million to more than 14 million pounds.
Inventory levels also continued to rise. More than half of reporting service centers indicated their inventories were on the rise during the month, while only about 10 percent reported declining inventory levels during March.

An unexpected change in March was the number of companies reporting they still had employees on short-time or lay off. The number increased from 26 percent in February to 31 percent in March for service centers, and from 17 percent to 50 percent for suppliers. Association officials say this is a number they will continue watch closely in the coming months to determine if it’s an anomaly or indicative of something else.

What's the Difference?

One of my first official lessons as a newbie in the Metals Industry was tackling some of the “What’s the Difference” questions.  This of course could apply to just about everything in the industry but I am specifically referring to learning the difference between Solid Bar, Cored Bar and Rectangular shapes.  I had to remember terms like ID and OD, width and diameter.  (Truthfully, my head would spin!) It did seem to me that it took forever to finally be able to distinguish them apart.  But thankfully I had some patient co-workers who would repeatedly explain the difference and eventually I got it.  Now all these years later I have found I am not alone!  It is amazing how many people will call looking to get a quote on material or just need some help and they too are asking, “What’s the Difference”?  It is very comforting. 

So for my first blogpost, I figured I’d pay homage to all the “newbies” with a little lesson on what is the difference between a Solid Bar, Cored Bar and Plate shape.  And what the heck I might throw in another shape for kicks!
SOLIDBAR

SOLID BAR
I'll tackle the easiest shape first - Solid Bar.  From the picture you can see that this shape is round and it's solid!  Hence the term "Solid Bar" and it's also referred to as Round Bar.  Solid Bar only has two dimensions to remember  --  a Diameter or also seen as "Ø" and a Length

A quick note on length - most bars in Bronze & Copper Alloys are available in any length up to 105" or 144" long.  But sometimes special arrangements can be made with a mill for longer sizes depending on your quantity. 
RECTANGLE
RECTANGLE
Next is Rectangle aka Plate.  This shape has 3 dimensions that you'll need to know.
1.) Thickness (or) Thick2.) Width (or) Wide
3.) Length (or) Long
Some people indicate these dimensions in millimeters and some in inches.  It just depends on where your from.  Also, some people won't even indicate a Length (or how long of a piece they need) but rather just supply you with a total weight (lbs) that they need.  That works too!

 CORED BAR
Then we have Cored Bar.  Oh, Cored Bar.  This definitely was the hardest for me to remember.  Some tried to give me the "Donut Analogy" but for some reason I still didn't get it.  It wasn't until I actually held a piece of Cored Bar in my hand that I got it.  And at that moment I was embarrassed. After all it's Cored!  With this shape, there are 3 main dimensions that you need to know:
COREDBAR2
1.) ID or Inside Diameter
2.) OD or Outside Diameter
3.) Length or Long
Simple enough right?  I just always got confused as to which was the OD and which was the ID.  So, I had to remember that the OD is always the larger dimension of the two.  Here's a tip:  These same dimensions are also true for Bushings (Plane or Sleeve Bushings). 






EXTRA - FLANGE BUSHING
Now for the "kicks" that I mentioned...here's a Flanged Bushing shape.  This one usually gets a lot of people.  They know to look for the ID, OD and Length of the Bushing, but they usually forget about the Flange OD & Flange thickness.  Take a look!
  FLANGEBUSHING2 The most important dimensions to pay attention to are: 
1.) ID or Inner Diameter of Bushing
2.) OD or Outer Diameter (or) Body OD
3.) Length of Bushing
4.) Flange OD (Outer Diameter)
5.) Flange Thickness
These particular bushings are available in a wide variety of alloys and they can even be self-lubricated (notice the black circle "graphite plugging" throughout the bushing) to make them easy to use and as maintenance free as possible.They are usually available off the shelf and pretty economical when ordered in large quantities.  But they can be Made to Order too using a print or drawing. 
I hope you found this post useful and informative.  I know that seeing the shapes and dimensions together was a great tool for me in understanding what was the difference!
PS:  Above photos are all courtesy Atlas Bronze and copyright protected

The Marriage of 2 Metals...a long time ago

Hi All!  This Brush Wellman Technical Tidbit was emailed to me and I thought it would be a great resource for some.  So enjoy....and learn :)  And just to make sure to give credit where credit is due, this was written by Brush Wellman.

 Solid Solution Hardening & Strength
(April 2010 updated from October 2000 Publication) by Brush Wellman

Approximately five thousand years ago, early humans discovered they could make a strong, tough metal by mixing copper and tin together. They had created the world’s first Alloy (a mixture of two or more metals). Unaware at the time, they were taking advantage of an important strengthening mechanism, solid solution hardening. The Bronze age therefore became the dawn of metallurgy.

Solid solution hardening is simply the act of dissolving one metal into another, similar to dissolving sugar into coffee. This is done during casting, when all the metals involved are in liquid form. For electrical connectors, copper is usually the main ingredient and is said to be the solvent, similar to the coffee in the above example. Other elements, playing the role of the sugar, to be added to the copper are known as the solutes.

There is a limit to the amount of solute that can be dissolved in to the solvent. This is known as the solubility limit. For example, coffee will only dissolve so much sugar before the excess settles on the bottom. However, raising the temperature of the solvent can often increase the solubility limit. There are several thermal strengthening methods that depend on having excess solute cast into the material and frozen into place when the mixture cools. Read More ......

Written by Mike Gedeon of Brush Wellman's Alloy Customer Technical Services Department. Mr. Gedeon's primary focus is on electronic strip for the telecommunications and computer markets with emphasis on finite element analysis (FEA) and material selection. Mr. Gedeon can be reached via email at alloy_tech_svc@brushwellman.com or by phone at 1-800-375-4205.