Author	[Modern View]
mkirsch 03-20-2013 11:58:18 64.80.110.74 Report to Moderator	Gonna pick on Lanse for a minute here. Thanks in advance for being a good sport. In Lanse's videos he advocates peening cast welds to relieve the stresses as the weld cools. He then uses a relatively SHARP instrument to hack away at his welds. Aren't you supposed to use the ball end of a ball peen hammer for this job? I would think a round blunt instrument would be the tool of choice for this process. When you go after it with the point of your chipping hammer you end up with something that looks like it was attacked by a woodpecker on bath salts! The sharp poke holes can't be good for the overall strength of the weld. [Reply]   [No Email]
Irvia 03-20-2013 20:26:50 207.199.229.145 Report to Moderator	Re: Peening welds in reply to mkirsch, 03-20-2013 11:58:18   I've never seen anyone use a ball pein hammer. You can't get down into the bottom of the weld. I usually use the dull pointed end of a chipping hammer. And, you don't have to beat the heck out of it, just upset the metal enought to give it some expansion. That's why nickle is used, for it malleability. [Reply]  [No Email]
Mel in SW Iowa 03-20-2013 19:11:04 75.105.35.117 Report to Moderator	Re: Peening welds in reply to mkirsch, 03-20-2013 11:58:18   Will using a needle scaler on a hot weld reduce weld stress? [Reply]  [No Email]
Dick L 03-20-2013 17:15:48 50.51.145.2 Report to Moderator	Re: Peening welds in reply to mkirsch, 03-20-2013 11:58:18   When Sohio instructed me in repair welding high pressure hydraulic pipe back in the 1960's, after the first hot pass it was necessary to peen with the sharp end of the chipping hammed hard. I was not instructed to peen the final pass. [Reply]  [No Email]
Puddles 03-20-2013 17:25:07 24.113.77.208 Report to Moderator	Re: Peening welds in reply to Dick L, 03-20-2013 17:15:48   It is written in the Lincoln Procedure Handbook of Arc Welding, not to peen the root pass, or cover pass. [Reply]  [No Email]
Dick L 03-21-2013 09:16:00 184.8.58.116 Report to Moderator	Re: Peening welds in reply to Puddles, 03-20-2013 17:25:07   The peening just reminded Of what I did which was different than the subject in the thread. However the high pressure hydraulic repair was not joining two sections of thick wall pipe but removing old weld with blow rod and rewelding cast steel fittings back on without loosing bolt on locations. When welding the hot root pass oil between the pipe and fittings would cause pin holes in the weld. The weld needed to be peened to close tight all pin holes or you could get pin holes that would seep. We did not have seeping with this procedure. [Reply]  [No Email]
Puddles 03-20-2013 13:17:52 24.113.77.208 Report to Moderator	Re: Peening welds in reply to mkirsch, 03-20-2013 11:58:18   When I worked in a tank shop, a lot of the tanks were laminated 3/4-inch thick steel, two halfs rolled to 8-feet diameter circle. We had to make the vertical welds on each side. To keep the steel from shrinking too far out of spec we used rivet busters with the gad ground down to a blunt looking chisel. These rivet busters hit so hard, if your partner was peening on one side you couldn't weld on the other side. http://www.northerntool.com/shop/tools/product_200338582_200338582?cm_mmc=Google-pla-_-Air%20Tools-_-Air%20Chisels-_-1540338&ci_src=17588969&ci_sku=1540338&gclid=CNOV4pqMjLYCFc5xQgods0oAgA [Reply]  [No Email]
el6147 03-20-2013 12:08:10 50.124.60.237 Report to Moderator	Re: Peening welds in reply to mkirsch, 03-20-2013 11:58:18   I haven't watched his video yet but I know if he is using the pointed end of the chipping hammer to stress relieve a cast weld he most certainly is doing it correctly and yes it will look like a wood pecker attacked it when the weld is finished . [Reply]  [No Email]
Stick welding 03-20-2013 16:08:25 198.53.83.89 Report to Moderator	Re: Peening welds in reply to el6147, 03-20-2013 12:08:10   No, a sharp chipping hammer shouldn't be used for peening. A dull chipping hammer would be a better choice and the idea is not to beat the snot out of the weld. That will increase stress rather than reduce it. Peening is supposed to reduce shrinkage stress while the weld is cooling. They make low stress stamps that are a series of dots because on critical jobs using standard stamps to identify who did the welding can be stress risers and/or a starting point for a crack. [Reply]  [No Email]
el6147 03-20-2013 18:19:46 50.124.60.237 Report to Moderator	Re: Peening welds in reply to Stick welding, 03-20-2013 16:08:25   I didn't say sharp I said pointed and I guess I could have been more clear and said rounded or dull pointed end , I have welded many cast housings cold with nickel without a failure . [Reply]  [No Email]
IrvIA 03-20-2013 20:19:14 207.199.229.145 Report to Moderator	Re: Peening welds in reply to el6147, 03-20-2013 18:19:46   Do you weld it across the crack as was suggested to me? I guess there's more than one way of doing things. Irv [Reply]  [No Email]
el6147 03-21-2013 09:34:42 50.124.60.237 Report to Moderator	Re: Peening welds in reply to IrvIA, 03-20-2013 20:19:14   I would guess everyone has their own way or technique , often one learns by doing and I don't believe there is one set of rules when it comes to cast . Often I v-groove , small holes and each end if it is a crack so the crack does't continue , single pass in the groove making sure all flux is cleaned out before your next short weld is started and I do what I would refer to as a side to side Z pattern on the cover pass or when the opening begins to widen as you stack weld on top of weld as your filling the V-groove and the absolute perfect way to weld cast is oxy-acetylene with a cast iron filler rod with cast flux and that one can only learn by doing . [Reply]  [No Email]
Stick welding 03-21-2013 22:16:39 96.53.210.246 Report to Moderator	Re: Peening welds in reply to el6147, 03-21-2013 09:34:42   Spray welding is also one of the best methods to repair cast as is brazing. Stick welding is just fine for some cast iron repairs. [Reply]  [No Email]
Stick welding 03-20-2013 19:41:05 96.53.210.246 Report to Moderator	Re: Peening welds in reply to el6147, 03-20-2013 18:19:46   A rounded chipping hammer will work but I've always read that over peening is worse than not peening at all. Reading some of the posts makes it sound like your supposed to beat the living daylights out of the weld, which would over peen it. [Reply]  [No Email]
rustred 03-20-2013 12:42:48 24.114.27.66 Report to Moderator	Re: Peening welds in reply to el6147, 03-20-2013 12:08:10   any time i have helped a welder thats how its done. also used dull air chizel on the welds. [Reply]  [No Email]