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Posted By: fast66 Best way to fix a cracked base? - Fri Dec 04 2009 07:38 AM
I need to fix a cast base that is cracked in two places a large piece is loose. Whats the best method?
thanks in advance!
Claes
Posted By: gasmansgp Re: Best way to fix a cracked base? - Fri Dec 04 2009 09:12 AM
There is only one correct way and that is to weld it. If you are unable, then find a good local welder. These guys know how to reattach castiron and in most cases can even fill a missing piece to make it look new. Good luck, Paul
Posted By: +Chris Holt Re: Best way to fix a cracked base? - Fri Dec 04 2009 10:40 AM
Claes, they have a lot of new cast welding rods on the market now, these rods work great even for a beginer ,just grove out the cracks and weld them up. its not like the old days when you had Pre/heat, post/Heat ,peen, the new cast rods are very forgiving. as far as filling in for a missing piece, I use a form of JB Weld, I build a form on the front of the cast piece out of tin and clamp it in place over the hole, and then working from the back I aply the JB WELD to fill the hole, I make it just a little thicker than the cast piece I'm filling . it will take you longer to make the form/mold from a piece of tin than it will to do the filling. once the JB WELD hardens remove the outer mold ,you may have to grind in the details of the cast piece but once you add a little bondo for touch up, primer,and paint you'll never see it. I hope this helps, I've done several pieces over the years with really good results.
Posted By: fast66 Re: Best way to fix a cracked base? - Fri Dec 04 2009 12:23 PM
Thanks guys,
I suspected that would be the way to go.
//Claes
Posted By: tallgye49 Re: Best way to fix a cracked base? - Fri Dec 04 2009 01:58 PM
Claes--

Brazing works well. I've repaired several bases that way. I've brazed steel onto a cast iron base to fill in a missing piece. A little smoothing with JB Weld on top and you're good to go. Either method described here will do the trick very nicely. Dave Folck
Posted By: gasoildude Re: Best way to fix a cracked base? - Fri Dec 04 2009 03:50 PM
Claes what pump does it go too?
Posted By: fast66 Re: Best way to fix a cracked base? - Fri Dec 04 2009 09:08 PM
it goes to the Silver colored Ljungmans pump I posted on BOTW (last week). I'm gonna pick it up tomorrow, and the seller called me and the base had cracked while he was moving it. I got somewhat concerned if I should skip the deal, but it was cheap enough to do a 2 hour drive anyway...I guess.
Posted By: st.rod Re: Best way to fix a cracked base? - Fri Dec 04 2009 11:24 PM
I used to work where they had a black smith shop. The whole piece would be cleaned VERY well then the entire piece heated, welded with special rod, cooled very slowly,,,,, blah blah blah

Someone finally told me to just bevel the area you want welded and turn up your mig welder to as hot as it will go and turn up the wire feed. Fill it, grind it, fill it grind it until you are satisfied. The base does not have to have the strength for display it had to have for duty. It will look great. It will paint or powder coat and you will be the only one that knows.

Larry
Posted By: lordparaffin Re: Best way to fix a cracked base? - Sat Dec 05 2009 12:50 AM
I've welded a lot of years both professionally and for myself and I can tell you unless you are comfortable and somewhat familiar with the welding process, I'd seriously consider for a little cash having someone who knows what they are doing do it for you. I only recommend using a stick welder for cast iron. I'd also consider finding a piece of cast iron of roughly the same thickness to practice on first to get the "feel" of how everything will go and work out any problems ahead of time. And old cast iron frying pan from a flea market won't cost much. The method of grinding a bevel or valley that follows the cracks leaving you someplace to fill in and also give you maximum area for the root of the weld to get penetration on is the best method. You'll need a small hard wheel grinder for this part of the job. If done correctly, you should be able to build a very small "hill" to the weld which can then be carefully ground down using a flexible pad grinder and blend to the same level as the casting. It's not difficult, but a little practice and preparation will go a long way. Good luck Claes.
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