MEMBER ITEMS FOR SALE
Custom Knives | Other Knives | General Items
-------------------------------------------
New Posts | New PhotosAll Photos



Go Back   The Knife Network Forums : Knife Making Discussions > Custom Knife Discussion Boards > Knife Making Discussions > The Newbies Arena

The Newbies Arena Are you new to knife making? Here is all the help you will need.

Reply
 
Thread Tools Display Modes
  #1  
Old 02-05-2015, 01:46 PM
dwc34205 dwc34205 is offline
Enthusiast
 
Join Date: Jul 2011
Location: Huntsville, AL
Posts: 46
Damascus warping

Thus far I have been having about the same string of luck and cannot figure out what I am doing wrong. Almost every third knife warps. It is not severe, but enough that it will need repair. The grind is symmetric, so I do not believe that is the reason. I am going into the oil edge down and not swishing side to side. I am going to 1550 degrees F and holding for 5-6 minutes. Then straight to quench oil. Oil is typically around 150 degrees. Any help on this would be greatly appreciated. Also, include how I should repair it.
Reply With Quote
  #2  
Old 02-05-2015, 02:24 PM
Ray Rogers's Avatar
Ray Rogers Ray Rogers is offline
Founding Member / Moderator
 
Join Date: Jun 2002
Location: Wauconda, WA
Posts: 9,788
What in the steel? Are you doing any normalizing cycles? Most of the time if a blade warps it is either because stress was induced by uneven grinding or because stress was already in the steel and the grinding simply released it. Either way, normalizing could be helpful.

If you are normalizing already then you might try just profiling your blade, doing the HT, and then grinding the bevels. I've done it this way for 20 years, lots of guys do. This method avoids a lot of stress related problems and, if the blade still warps, its usually much easier to straighten the blade if you haven't ground it yet ...


__________________

Your question may already have been answered - try the Search button first!







Last edited by Ray Rogers; 02-05-2015 at 02:27 PM.
Reply With Quote
  #3  
Old 02-05-2015, 03:50 PM
dwc34205 dwc34205 is offline
Enthusiast
 
Join Date: Jul 2011
Location: Huntsville, AL
Posts: 46
5160, 203E, 52100, 15N20 are the materials. It is from Alabama Damascus.

Two questions for you Ray- 1) What is the normalizing process? 2) Do you do anything special to keep temp down when grinding after heat treat? I may try your method on the next one.
Reply With Quote
  #4  
Old 02-05-2015, 04:07 PM
Ray Rogers's Avatar
Ray Rogers Ray Rogers is offline
Founding Member / Moderator
 
Join Date: Jun 2002
Location: Wauconda, WA
Posts: 9,788
I know a lot of people have good luck with Alabama damascus but that mix of metals can be problematic. The reason why most pattern weld steel is made from 15N20 and 1084 is that those two have almost identical HT requirements. When you start mixing steels whose requirements are too far apart you get billets that try to tear themselves apart as yours seems to be doing. Now, if you are Kevin Cashen you might have the knowledge and the equipment to pull that off and get good results but most of us mortals just can't do it. With a mix like you have there doing the HT for the largest component is about the only way you can go. That means some of those steels may be over heated or some will be under heated but it will be very difficult to avoid some kind of internal stress. Normalizing should help, no promises, but its about all you can do aside from a lot of experimenting. FWIW, I believe Alabama has HT instructions for their steel that you could try.

For normalizing, the usual process is to heat the steel about 150 degrees beyond non-mag (no getting around it, you MUST know when the steel becomes non-magnetic) then letting it cool in still air until it turns black (all color is gone but the steel is still very hot). Then heath the steel again and repeat for a total of three times. After that, heat the steel to non-mag and quench as you normally would ...

PS

As for grinding after HT, just grind bare handed so you can feel the heat. If you can take the heat the blade isn't too hot yet. Dipping the blade in a bucket of water after every pass or two works for me. You need to use a fresh ceramic belt. Fresh sharp belts run cooler than worn belts. Use an old belt to take the corners off the edge before switching to a new belt or you'll just ruin the new belt before you even get started. You can see all this on my Shop Chef video along with a few other useful tidbits...


__________________

Your question may already have been answered - try the Search button first!







Last edited by Ray Rogers; 02-05-2015 at 04:11 PM.
Reply With Quote
  #5  
Old 02-05-2015, 04:57 PM
ricky_arthur's Avatar
ricky_arthur ricky_arthur is offline
Skilled
 
Join Date: Dec 2012
Location: Utah
Posts: 524
As far as what to do about it now. The best way I've found so far with minimal chance of breaking the blade is this. Use a piece of angle iron. Clamp the blade up against the angle iron with a shim in the outside of the bow, and between the angle iron and the blade. just snug it up to start. Put the whole thing in your tempering oven. and bring it up to your temper heat. I like about 410 for Alabama damascus. when it all gets up to temp (10-15 minutes) turn the clamps to bend it back just a little beyond straight and return to oven for an hour. Then remove and cool in water and check to see if its straight. It usually is. If not repeat the process but bend a little further beyond straight. FWIW ive had my very best results with Alabama damascus and Its my go to Damascus. I've tried several other suppliers and was less impressed.
Reply With Quote
  #6  
Old 02-05-2015, 05:20 PM
jmccustomknives jmccustomknives is offline
Skilled
 
Join Date: Mar 2012
Location: Alabama
Posts: 554
The thickness of the blade will have a lot to do with warping. Thin blades just want to warp. You can do like Ricky said, just make sure you are at the proper temp. When I straiten my blades I use a torch and give it a soft back draw then I can tweak it without fear of breaking it. Remember, any adjustments should be done at tempering temps.
Reply With Quote
  #7  
Old 02-06-2015, 10:01 AM
dwc34205 dwc34205 is offline
Enthusiast
 
Join Date: Jul 2011
Location: Huntsville, AL
Posts: 46
Ray- Thanks for the input and I am going to give your method a try next time. Especially with a recent order for a Bowie made from Damascus.

Ricky- I am going to give your recommendation a try today. Wish me luck.

JM- A torch is going to be my backup at fixing it. I don't have a lot of experience drawing a spine, so I am little more timid to do it that way. The thickness of these is around .150", so I am surprised that this happened.

Thanks for all the help and input. Will update with the results.
Reply With Quote
  #8  
Old 02-08-2015, 06:56 AM
Crex's Avatar
Crex Crex is offline
Moderator
 
Join Date: Sep 2002
Location: Acworth, GA and/or Hanging Dog, NC
Posts: 3,481
Simple or as hard as using quench plates in conjunction with your oil quench (as described). Bring to temp - quench in oil - when it gets down around 700* (oil stops bubbling and boiling around the steel), remove and quickly clamp in quench plates to finish cooling. Have done fillet and chef knives this way for years, both plain homogenous and Damascus (why a customer wants a fillet out of Damascus is beyond me but.......they are always right).
I do agree wholeheartedly with what Ray has said on proper prep to heattreatment, normalizing is way to often overlooked as the culprit. Also, that combination of steels.....one can only ask why?


__________________
Carl Rechsteiner, Bladesmith
Georgia Custom Knifemakers Guild, Charter Member
Knifemakers Guild, voting member
Registered Master Artist - GA Council for the Arts
C Rex Custom Knives

Blade Show Table 5-J
Reply With Quote
Reply

Tags
1084, 5160, 52100, 550, art, bee, blade, bowie, damascus, degrees, edge, grind, grinding, heat, heat treat, hot, knife, knives, made, materials, pattern, repair, steel, warping, weld


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
o-1 warping Mitchell H. Heat Treating and Metallurgy 11 03-12-2006 01:51 PM
Blade warping alexkuzn The Newbies Arena 2 01-06-2006 12:31 PM
Help, I'm warping! ErnieB Ed Caffrey's Workshop 9 08-15-2005 04:03 PM
warping? doublearrow The Newbies Arena 1 03-23-2003 06:05 AM
warping trail angel The Newbies Arena 5 02-07-2002 11:10 PM


All times are GMT -5. The time now is 05:21 PM.




KNIFENETWORK.COM
Copyright © 2000
? CKK Industries, Inc. ? All Rights Reserved
Powered by ...

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
The Knife Network : All Rights Reserved