keeping tool steel from warping?

[vinny1892]

how is one suppost to keep w1 drill rod from warping when heat treating it ? I plan on making swaging dies out of one inch w1 but i may not if i cant control the warpage. hope some one can help thanks.

[chuckbuster]

Friend of mine owns a Heat Treating shop, does small batch tool work not production/large quantity. I'll ask him for any tricks.

[blaser.306]

W-1 may distort "some" others are more stable 0-1, A-2, 0-6 under heat and quench cycles. The minimal amount that you will see for a one inch cross section ( and not overly long ) likely will not even be noticeable to a hobby machinist! You will already be leaving enough material to lapp to final diameter and roundness, I do believe that the warping incurred will go away with your tooling marks inside the die body when it is polished to size. When getting started I discovered I was over thinking every operation too much, be confident in what you are doing and enjoy the process. It is all about learning. Some people pay THOUSANDS of dollars learning the trade and never make a part? Where the hobby machinist does it for the enjoyment / challenge, valuable lessons are taught when a pice with many hours is relegated to use as a shiny paper weight and lasting reminder of how not to do something. The worst that happens is you make a few prototypes!!! Just my opinion and YMMV.

[country gent]

ALot has to do with internal stress in the material. Its part of the process of making the mateial. If you can find stress relieved material great. if not you can try it your self heat to 400* and cool several times these heat cycles tend to normalize te grain and relieve some stress making the material less prone to warpage when machining and somewhat during heat treat. Quench quickly evenly and from a consistant point. the part on a heavy wore form or in cup or holder to heat treat then use tis to pick it up. On round parts when hot whats thought to be warpage may be crush from softer metal and the tongs. This also allows round parts with a hole to be lowered into quench end first cooling more even. Its more watching what your doing, cool quickly and evenly as possible from a direction side thtat allows quick even immersion from as many sides as possible. Dont grasp the part but a rack or form.

[vinny1892]

ok thanks

[dkf]

Using water for quenching is one of the most violent (rapid) methods of cooling the part. Air hardening is one of the least "violent". For thinner parts that may warp I use an air hardening tool steel if I can get away with it, like A2. A tube is usually fairly stable if the walls are not too thin. However it is not uncommon to get dimensional changes after heat treat.

[BigEyeBob]

W1 is supposed the quenched in a brine not plain water. Well that's what I was taught .I always use 0-1 or similar , grade eight bolts make good punches and cutting tools , if hardened and tempered properly in oil. I make D cutters and shim punches from them . I also use 7/8 x 14 bolts to make forming dies and bullet sizing die and harden them by heating to a dull red and keep them at that temp for a time depending on on the size , then quench in dirty engine oil . Then when cool polish and temper to a straw colour. I'm an old school machinist and make most of my tools.

[Ballistics in Scotland]

Brine is even more abrupt in quenching than pure water, although it may be more even due to reduced gassing. There are few applications, especially for the amateur, for which air hardening steel isn't good enough. I would also avoid knurling the outside of dies.

[waksupi]

I take a rod of steel, heat it red hot, and put in the quench to raise the temperature. Then I do my work piece. That has eliminated some problems with warp for me.