Replies

1. 
   billyg83440 | Jul 15, 2003 11:50pm | #1

   Not sure what exactly you're talking about as I haven't seen titanium woodworking saw blades.

   I do purchase metal working bits, taps, endmills, ect. Time to time. A Tin (Titanium Nitride) coating is very useful on a HSS tap or drill bit. It does help it last longer.

   You can also get TiCN (titanium Carbonate) or TiALN (Titanium Aluminum Nitride) coatings. TiCN is reputed to perform almost as well as carbide. TiALN is for really high speed cutting, or cutting w/o lubricants so it's high temp.

   But, all of these coatings are put on High Speed Steel cutters. I've never heard of any titanium cutter directly competing with carbide, they just help the HSS cutters last longer &/or work better. And, they're cheaper. HSS 3/8" endmill w/ 1.5" cut length: $14.00, HSS TiN coated $15.50, solid carbide $57.50.

   I've never seen these coatings on carbide. You may be seeing someone selling TiN coated HSS sawblades. They're probably right that those blades will last 3 times longer then plain "HSS" sawblades, but neither will come close to lasting as long as a good carbide sawblade.

   Curious, exactly what blade are you asking about? Can you post a link?

1. 
   tzach | Jul 16, 2003 07:43am | #2

   There are places that will TiN coat carbide but I haven't seen or heard of this done on

   a ts blade.   Maybe someone will have some experience with this and post.   

2. 
   UncleDunc | Jul 16, 2003 05:46pm | #5

   >> I've never seen these coatings on carbide.

   I can't speak to woodworking tools, but in metalworking I've seen lots of TiN coated carbide cutting tools and carbide inserts, and even used a few.

1. 
   billyg83440 | Jul 16, 2003 07:54pm | #8

   Actually after I wrote that I remembered that lots of the carbide inserts we've used are Tin Coated.

   We're too cheap to buy solid carbide cutting tools.<G>

   Depending on what you're cutting it may be advantageous. The main purpose of the Tin coating, as I understand it, is to resist dulling from cutting abrasive materials. So, if you're using a blade to cut lots of rough wood that may have dirt in it, or lots of MDF it may be worth a bit extra to get the extra abrasion resistance.

   Question: Are the vermont america saw blades any good. This may be worthwhile on a good quality blade, but if the blade isn't that good, no coating will substantially help this.

1. 
   bobhallsr | Jul 18, 2003 06:49am | #16

   I stayed out of the nitride-nitrite and the metal-ceramic thing because I knew you all would get it right.  My understanding of TiN is that an important atribute is that it is low friction.  Metal does not pile up at the cutting edge and the chip comes away freely.  This makes it cooler cutting and in essence, sharper.   If this is correct, I wonder whether it provides much advantage in wood working as opposed to metal working.

   BJGardening, cooking and woodworking in Southern Maryland

1. 
   billyg83440 | Jul 18, 2003 07:16pm | #17

   I'm not sure it provides any advantage in WWing either.

   McMaster suggest increasing drill speeds by 25-30% when using TiN coated bits. Not something you can do on a table saw, though if you could, you'd likely be able to get smoother cuts.

   For metal working, TiN is a great thing, and works well. We no longer buy plain HSS taps, as the TiN coated ones last much longer, and seem to have fewer breakage problems, probably because of the reduced friction.

   Still, it is very likely, that TiN coated saw blades will become very common. It is very likely that coated blades will stay sharper longer. Frankly I can't see any downside to coating, but I'm no expert on metals.

2. 
   eddiefromAustralia | Jul 21, 2003 04:42am | #18

   Can't comment on how it improves wood surface as I've never tried them, but the titanium nitride coating is deposited onto the surface of the tools as it is very hard, avoiding sliding wear - that is why you see drill bits coated in TiN.  As well, it can smooth out irregularities in the surface, causing a drop in friction.

   The coating is very thin and does little for the edge retention properties.

   Cheers,

   eddie

   Who is a metallurgist and used to operate a steel vacuum degassing station, amongst many other roles/responsibilities.

   ps: (edit) TiCN = Titanium CarboNitride, a harder version of TiN, having just read post #2 in this thread.

   I looked up the Vermont site.  Titanium Carbide is harder than Tungsten carbide and may wear longer (or it may chip easier - I can't answer that one without using it).  I don't know how important having a 'sharper' blade is after you cut the first 20' of material - the superfine edge may just fritter away quickly

   Edited 7/20/2003 9:54:51 PM ET by eddie (aust)

3. 
   davearnone | Jul 21, 2003 05:08pm | #19

   BJ, TiN's important property is wear resisitance.  In tribology literature TiN running on TiN is the only zero wear pair quoted. 

   With respect to friction, TiN is not particularly low friction in fact it is quite sticky. 

3. 
   gpasewicz | Jul 16, 2003 07:36pm | #6

   Vermont American has a line of tablesaw blades it calls Titanium Carbide.  

   http://www.vatool.com/Catalogs/

2. 
   WorkshopJon | Jul 16, 2003 12:56pm | #3

   G,

   I think you are referring to titanium nitrite coating. It is no substitute for a solid or tipped (carbide) tool. It does add a little to life though. BTW, though I've never seen it in woodworking tools, carbide cutting tools do come TN coated.

   Titanium itself is not that hard an alloy (compared to carbide or cobalt steel)

   Jon

1. 
   jhausch | Jul 16, 2003 01:08pm | #4

   I am sure some metalurgist will chime in on this, but I the point of TN is the N.  I think the Nitrogen is what increases the surface hardness of the steel.Steelkilt Lives!

1. 
   gpasewicz | Jul 16, 2003 07:40pm | #7

   I'll ask my wife.  She got her Ph.D. in metallurgy.  Her thesis was on steelmaking, specifically vacuum degassing and removing nitrogen from the ladle.

2. 
   gpasewicz | Jul 16, 2003 07:57pm | #9

   I asked my wife.  Nitrogen does make steel harder.   Titanium Nitrite is a ceramic. 

1. 
   steves | Jul 17, 2003 01:42am | #10

   I don't know where you got your info from but titanium nitrite is a metal not ceramic. Also, the coating used on tools is titanium nitride (not nitrite).

   The coating is used on both HSS and carbide inserts for the metalworking industry because of its high wear resistance and low cost.

   Kennametal is a big manufacturer of these types of tools.

   http://www.kennametal.com/en/metalworking/mw_home.jhtml

1. 
   UncleDunc | Jul 17, 2003 09:20am | #11

   >> ... titanium nitrite is a metal not ceramic.

   Titanium is certainly a metal, but titanium nitride or nitrite could still be a ceramic, just as aluminum is a metal, but aluminum oxide is a ceramic. In fact most naturally occurring clay is a mixture of aluminum and silicon oxides. Other metals whose oxides are ceramics include potassium, calcium, magnesium, beryllium, and lithium.

2. 
   gpasewicz | Jul 17, 2003 03:56pm | #12

   I got the info about titanium nitrite from someone who has a PhD in metallurgy and worked in a mill manufacturing specialty alloys.   True it was an "off the cuff" answer, but I trust the source.

3. 
   steves | Jul 17, 2003 05:18pm | #13

   Well dang if your PhD isn't right; it is considered a ceramic strangely enough. My apologies. It is nitride not nitrite however, which if I remember chemistry is a one atom difference in the molecular structure.

   Here's a good web site for material info http://www.matweb.com/search/SearchSubcat.asp

4. 
   gpasewicz | Jul 17, 2003 05:27pm | #14

   She's always right.  ;-)

3. 
   farwood | Jul 18, 2003 05:52am | #15

   I believe what Vermont American is referring to is the type of carbide used in the blades.  Most "carbide tipped" blades are a tungsten carbide formulation IIRC.  What they are using is a titanium alloy carbide.