Some time ago we posted an article about random bar lengths. The attention from that blog contributed to this follow-up about cut-to-length bars. More importantly, how that term differs from random (rdm) bar lengths.
Random bar lengths can be anything the distributor deems beneficial to his selling of the steel bars in his, or her, inventory. It is most common in the general steel marketplace to see random bar lengths listed as 10/12ft rdm, stainless bars were often listed as 11 to 14ft rdm. You might say that is more less the default in the industry. However, even that category does not define exactly what might be shipped to you. You may get a 13ft bar, or even a 16ft bar; depending on what the distributor has on the floor at the time. In rare instances you may get an 8ft bar or 9ft bar, although shipping a shorter bar is not all that common. The practice of offering random bar lengths can be a very good thing. You should be able to save money on the purchase, less than the higher cost of requiring a bar to be cut to a specific length. Just make sure you and the seller are on the same page at the point of inquiry.
Cut-to-length bars are just that; bars are cut to the exact length you require. You just need to be clear in expressing your requirements; and include a length tolerance that works for both parties. For many decades “plus 1/8″, minus 0” was quite common, and the default if nothing was specified. It pays to be sure both parties understand the same requirement. Especially if it is a first time order or a new vendor or customer. Your expectations understood by one supplier may be lost on the new supplier.
There are other concerns that may affect your order regarding cut-to-length. You may want to specify “No Mill Ends”, or, “Trim Mill Ends”. Mill ends (the original ends of the bars as they were shipped to the distributor from the steel mill), may have been trimmed at the mill, and just fine. They may also be sheared, in which case there may be a slight taper to the end of the bar. The diameter at the bar end may be a bit undersize. It may not be a square cut. It may be slightly dished, it may have identification stamped into the end. If you have not allowed some trim stock to the length you ordered, this may be an issue. It is not a major issue on most orders, but it is worth mentioning if it could be.
If the type of cut required is to a very close tolerance you may want to specify “Square Cut Ends”, and then the tolerance you require. There may be additional charges depending on how specific your needs are.
Very small diameters (those under 5/8″ Dia.) may require special dialogue or instructions if your expectations are exacting. Can the vendor bundle and cut? Once again, there could be additional charges incurred. Very large diameters (over 10″Dia.) usually require a little extra stock be left on the cut. Depending on the size and the intended use, some people will leave 3/8″ or 1/2″ on the cut. Chromed bars often come with “masked areas” at the end of mill length bars. That is an area that has not been chromed. It may be several inches. If you typically purchase full mill random lengths of chrome bars from one supplier, you may want to insure both you and your new supplier understand the specific bar mults of the finished shafts you intend to make. Discuss “trimmed ends” at the point of inquiry.
Newer saws and better saw blades are able to cut phenomenally close these days. There seem to be blades for nearly every metal and hardness. But, just because the saw and the blade can cut close, does not mean that’s what you will be getting. Communication goes a long way to avoid a mishap. Remember; “When it goes bad, who’s wallet comes out?”
-Howard Thomas, June 21st 2019