macbruce Posted May 29, 2011 Share Posted May 29, 2011 What's a good stick rod to fill a crater in the bottom of a 50LB LG anvil dovetail that's pretty machinable ? Thanks........mb Quote Link to comment Share on other sites More sharing options...
NeatGuy Posted May 30, 2011 Share Posted May 30, 2011 I had a 50 lb Little Giant that had problems with the bottom of the die cavity as well. I wanted to weld it up but was dissuaded by Sid Suedmeier due to potential complications inherent with welding cast iron. Instead I ground and filed it flat, drilled and tapped two holes in the bottom then bolted a steel plate in to shim it back up to the required height. I know that is not what you were asking but I think it is better alternative to welding cast iron. brad Quote Link to comment Share on other sites More sharing options...
arftist Posted May 30, 2011 Share Posted May 30, 2011 7018 will work pretty well as will 70 series MIG wire. Yes, I saw that it is cast iron. If you want something "stickier" but still machineable, 309 stainless would be nice, but 308-16 will work good too. If you want to spend some bucks get a special purpose machinable nickel rod. I highly recomend MG products for special purpose rods. Quote Link to comment Share on other sites More sharing options...
clinton Posted May 30, 2011 Share Posted May 30, 2011 I think that I used cast iron rod on my dovetail repair, keep it cool, go slow small beads and peen the area as you gohttp://www.lincolnelectric.com/en-us/support/welding-how-to/Pages/welding-cast-iron-detail.aspx Quote Link to comment Share on other sites More sharing options...
monstermetal Posted May 30, 2011 Share Posted May 30, 2011 What is the purpose of the repair? is it structural/support? is the die not supported like it should be? if its just to fill a hole I think I would braze it up and grind it flat.... simple and easy Quote Link to comment Share on other sites More sharing options...
macbruce Posted May 31, 2011 Author Share Posted May 31, 2011 I think that I used cast iron rod on my dovetail repair, keep it cool, go slow small beads and peen the area as you go Keep it cool?........that kinda contradicts everything I've ever been told or practice re cast welding...........is that something you've had luck with Clint? I never had any luck with CI until I began pre heating the stuff, and post on occasion............. The divet on the bottom of the dovetail is causing the bottom die to miss align.......the hammer is real old, my friend said it was made before LG started keeping records of hammer sales. Brass still might hold up since it's very soundly supported, or maybe silicon bronze laid in with a tig.......................Thanks all, If there's any other ideas that's AOK too...........mb Quote Link to comment Share on other sites More sharing options...
clinton Posted May 31, 2011 Share Posted May 31, 2011 If you read the how to in the link from Lincoln you will see there are two ways to repair cast iron- preheat and cool down slow or keep it cool by running small beads and penning to relieve the stress. I have done the keep it cool method more than once with good results, I ended up with one piece of cast and not two, no cracks just good sound metal. I repaired a swage block this way that was a poor casting and I think it is still being used by one of the members of this site Quote Link to comment Share on other sites More sharing options...
BM454 Posted June 2, 2011 Share Posted June 2, 2011 What happens with cast is the filler metal (weld) and the base metal (cast) cool at different temps. That being said, it causes stress cracks. And due to the fact cast is a really dirty metal does not help either. Some cast welds beautifully and some not so well. There are tricks to keep it from cracking to much but, it still happens somewhat. You can drill a hole at each end of the crack and it will help it from cracking more. Preheat helps in some cases as well as a post heat and a very slow cool down time. Cover it up with insulation if you have it. With the machine being as large and as much mass as it has there, you should be able to do small weld and keep it cool. Takes a bit more time though. Scott Quote Link to comment Share on other sites More sharing options...
arftist Posted June 3, 2011 Share Posted June 3, 2011 What happens with cast is the filler metal (weld) and the base metal (cast) cool at different temps. That being said, it causes stress cracks. And due to the fact cast is a really dirty metal does not help either. Some cast welds beautifully and some not so well. There are tricks to keep it from cracking to much but, it still happens somewhat. You can drill a hole at each end of the crack and it will help it from cracking more. Preheat helps in some cases as well as a post heat and a very slow cool down time. Cover it up with insulation if you have it. With the machine being as large and as much mass as it has there, you should be able to do small weld and keep it cool. Takes a bit more time though. Scott This be true. Considering the size, and especialy the shape of a little giant anvil, I would weld it cool with an 1/8" MG 600 rod. A good welding supplier should be able to sell you one pound of MG 600 (about $50, well worth it). Make 1/2" long welds at the most, peen the center of the bead with the pointy end of a chipping hammer, well radiused, and wait. Waiting is how you keep it cool. Quote Link to comment Share on other sites More sharing options...
BM454 Posted June 4, 2011 Share Posted June 4, 2011 7018 will work pretty well as will 70 series MIG wire. Yes, I saw that it is cast iron. If you want something "stickier" but still machineable, 309 stainless would be nice, but 308-16 will work good too. If you want to spend some bucks get a special purpose machinable nickel rod. I highly recomend MG products for special purpose rods.7018 works well on cast. Most people don't know that though. For what you are using it for it would work just fine. Much cheaper than nickel rods too. MUCH cheaper! Quote Link to comment Share on other sites More sharing options...
clinton Posted June 5, 2011 Share Posted June 5, 2011 A needle scalier works good for penning Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.