Damascus - Prep

[ThorsHammer82]

What do you guys use to prep your layers for Damascus? Hard grinding wheel, Flappy paddle wheel, wire wheel?

chemicals?

I know that the point is to have them clean, and some of these leave residue and or grit behind which would effect the weld correct?

[TwistedCustoms]

For 1095 and 15n20 I grind the mill scale off on a 2x48 ceramic belt @ 120 grit, (I don't have a 2x72) and then clean them with mineral spirits before I stack them up. Weld a bead down both ends of the stack with the mig and most of the time tack on a handle.

[Buzzkill]

My prep is quite similar. Usually 60 grit ceramic belt to get a fresh steel surface. IMO ceramic belts leave very little residue on the steel, but I wipe each one before stacking just in case. JPH posted a tip somewhere that leaving grinding lines at roughly a 45 degree angle on the surface(s) to be welded helps pull flux in with capillary action so I do that as well.  If there will be any significant delay between stacking and heating I hit the stack with WD-40 to help keep oxygen from the weld surfaces.  It burns off cleanly in the forge and does not appear to impede welding at all.

I normally use rebar for the handle.  For some reason to me it doesn't seem like the heat travels as far or fast up the handle when I use rebar compared to straight round stock.  I usually only weld the stack on the handle end though.  For thin pieces you can get some buckling in the outer layers of the stack while it's heating up if you tack both ends. Some people tie the other end with wire instead.  I've had good success without doing that, but I'm usually welding 1/8" or thicker pieces together.

As long as you have clean and un-oxidized mating surfaces, with the correct temperature and a little coaxing from the hammer your success rate should be high.

[ThorsHammer82]

Rebar is typically mixed alloys, along with the shape and how that shape is made probably has something to do with why heat would travel down it slower than round stock. at least that's my guess.

Thanks guys. I currently have a 6x48" /9" Disc sander and a 1x30/5" disc sander. Is it easy to find ceramic consumables for those sizes?

[Jclonts82]

I'm pretty similar to Buzzkill. I hit both sides with a rough belt grinder. I prefer rougher, lower grit, because in my mind (a scary place to be sure) it leaves more surface area on both sides of the welding surface, and those little ridges and valleys have a greater chance to intermingle at high temperature. I have no data or sources to back this up, but I picture the roughed up sides acting almost like Velcro that then gets melted together if that makes any sense.  I dont have any sources or data for this reasoning, just my own extensive chemistry and physics background. 

 

I do differ in that I don't like using rebar, I prefer 1/2-5/8 square stock.  I find it hit or miss that the arc weld from rebar to the billet will stay throughout the stresses of hammering. Since rebar steel composition is a random bag of who knows what, sometimes you can get some alloys  in there that don't like to arc weld to HC steels.  my 2 Cents anyways

10 minutes ago, ThorsHammer82 said:

Is it easy to find ceramic consumables for those sizes?

Econaway abrasives. custom belts that they make to fit virtually any sized belt you need, just choose the abrasive, Aluminum oxide, silicon carbide, zirconia alumina,  ceramic. and input the sizes. its the only place that has reasonable prices for my oddball 4 X 106 belt grinder. the shipping is not the greatest, but ordering many belts at a time usually mitigates that cost a little bit. 

[Steve Sells]

 in case ya missed it there are a few threads on this in the knife making area