racer Posted February 14, 2007 Report Share Posted February 14, 2007 Is this hard to do? make sure its straight, then weld er up right? dont use filler so you dont throw it off balance and that should be all right? Quote Link to comment Share on other sites More sharing options...
okbeast Posted February 14, 2007 Report Share Posted February 14, 2007 Jared(bigred) did a thread on this awhile back where he did one of his. I guess the only thing you can't do (or maybe you can, not exactly sure) is "true" the crankshaft, which I'm not sure exactly what that entails so....might be possible. Quote Link to comment Share on other sites More sharing options...
jeepman380 Posted February 14, 2007 Report Share Posted February 14, 2007 Have to put it on a trueing stand to make sure it's true then use a TIG to weld it up. You can use fill rod but a very small amount is needed or you don't have to use any. It's hard to do if you don't know what you are doing. You got to get it withing spec...a few .001's of a inch. Quote Link to comment Share on other sites More sharing options...
BigRed350x Posted February 14, 2007 Report Share Posted February 14, 2007 Don't use filler rod. Just melt your crank web and the pin end together real good and your set... Oh yeah, make sure its true before you go to town on it. Not much is required all your wanting to do is keep the web from separating from the pin. Quote Link to comment Share on other sites More sharing options...
FireHead Posted February 14, 2007 Report Share Posted February 14, 2007 Like Jared said, no filler, make sure you true it first. It's easy to do. You don't need a trueing stand, you can use a lathe to accomplish the same thing. You need to chuck it between centers and run a dial indicator on the main bearing races. This gets you the same thing as setting the crank on those areas with a trueing stand. I figures I'd toss that out there since it seems that alot of people don't have trueing stands anymore. :thumbsup: Quote Link to comment Share on other sites More sharing options...
jeepman380 Posted February 15, 2007 Report Share Posted February 15, 2007 Don't use filler rod. Just melt your crank web and the pin end together real good and your set... Oh yeah, make sure its true before you go to town on it. Not much is required all your wanting to do is keep the web from separating from the pin. What was your amperage? Quote Link to comment Share on other sites More sharing options...
FireHead Posted February 15, 2007 Report Share Posted February 15, 2007 What was your amperage? 80-120 ought to get the job done. :thumbsup: Quote Link to comment Share on other sites More sharing options...
racer Posted February 16, 2007 Author Report Share Posted February 16, 2007 Like Jared said, no filler, make sure you true it first. It's easy to do. You don't need a trueing stand, you can use a lathe to accomplish the same thing. You need to chuck it between centers and run a dial indicator on the main bearing races. This gets you the same thing as setting the crank on those areas with a trueing stand. I figures I'd toss that out there since it seems that alot of people don't have trueing stands anymore. :thumbsup: I had forgotten about making this thread, haha. Whoops. Firehead can you elaborate more on truing with a lathe? I dont have a stand so thats my only option. Quote Link to comment Share on other sites More sharing options...
BigRed350x Posted February 16, 2007 Report Share Posted February 16, 2007 What was your amperage? I don't remember exactly but it was somewhere from 100-115. Miller Syncrowave 250. Quote Link to comment Share on other sites More sharing options...
FireHead Posted February 16, 2007 Report Share Posted February 16, 2007 I don't remember exactly but it was somewhere from 100-115. Miller Syncrowave 250. I used the same brand and model of welder. :thumbsup: Quote Link to comment Share on other sites More sharing options...
FireHead Posted February 16, 2007 Report Share Posted February 16, 2007 I had forgotten about making this thread, haha. Whoops. Firehead can you elaborate more on truing with a lathe? I dont have a stand so thats my only option. Basically you need to throw a 5C collet rig in the head stock and put a dead center in that. Then wou need to put a live center in the tail stock and place your dial indicator on a mag. base on or about the tool post. After you have that set, put the crank inbetween cennters and roll it over by hand. You shoul be inspecting the main bearing areas and the o.d. of the webs. If these are all running true then your pins should be in phase. One of the things I like about the lathe trueing method is that you can whack on the crank to straighten it out without having to take it out of your measuring setup everytime. :thumbsup: You can make the call on how much run out you want (this may be dictated by the accuracy of your dial indicator). I ususally true my cranks to within 5 microns or less total runout, but for everyone else 30 microns or less is probably satisfactory. Quote Link to comment Share on other sites More sharing options...
racer Posted February 16, 2007 Author Report Share Posted February 16, 2007 You can make the call on how much run out you want (this may be dictated by the accuracy of your dial indicator). I ususally true my cranks to within 5 microns or less total runout, but for everyone else 30 microns or less is probably satisfactory. Thats a sweet method. Will do for sure next time I have the crank out. But how the fuck do you fget accurate down to 5 microns? Quote Link to comment Share on other sites More sharing options...
FireHead Posted February 16, 2007 Report Share Posted February 16, 2007 Thats a sweet method. Will do for sure next time I have the crank out. But how the fuck do you fget accurate down to 5 microns? I usually true my cranks up on our balancer. It's pretty much the most accurate tool for balancing and trueing an engine rotation assembly that you could possibly buy. I think we spent about $300k on it a few years ago. It's really designed for the aerospace industry and is overkill for pretty much everything. The company who makes the things had only sold like 5 of the machines, total. If I were doing a friend's crank or something I was just going to blow up on the dyno, I would do the method I mentioned with the lathe. :thumbsup: Quote Link to comment Share on other sites More sharing options...
jeepman380 Posted February 19, 2007 Report Share Posted February 19, 2007 80-120 ought to get the job done. :thumbsup: That seems kinda low. Doesn't seem to get enough penetration with that low of amperage. 120 might cut it but anything lower than that wouldn't get enough penetration IMO. Quote Link to comment Share on other sites More sharing options...
FireHead Posted February 19, 2007 Report Share Posted February 19, 2007 That seems kinda low. Doesn't seem to get enough penetration with that low of amperage. 120 might cut it but anything lower than that wouldn't get enough penetration IMO. It depends on many things such as the welder, tungsten used, technique, etc. Remember, you are just providing a mechanism to preserve the press fit of the pin into the crank web. You are not attempting to forgew the two together. :thumbsup: Quote Link to comment Share on other sites More sharing options...
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