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Build-Ups \  T.B.C's Current Shop Truck Project 1990 Chevy

T.B.C's Current Shop Truck Project 1990 Chevy

Build-Ups General Discussions
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tre5   +1y

Ahh, the beauty of that body style chevy... no need to clearance the tranny tunnel and you can fit a 22 without coing anything to the firewall. The thing about the cast center section... Scares me to see it, but if you have convidence in it, then whatever it's your shop... do what makes you feel good.
TBCWORKS   +1y


Can't we all just get along??? "Hate breeds anger and anger never preceeds good acomplishments"Anyway...here is some literature that will help understand the procedure of welding cast iron.AdamTBCGuidelines for Welding Cast Iron

BackgroundCast iron is difficult, but not impossible, to weld. While there are a variety of types of cast iron, the most common is gray cast iron, and these guidelines are directed toward this type of material. 

A few facts about cast iron help in understanding the welding challenges. Cast iron typically has a carbon content of 2% - 4%, roughly 10 times as much as most steels. The high carbon content causes the carbon to form flakes of graphite. This graphite gives gray cast iron its characteristic appearance when fractured.

When castings are made, molten iron is poured into a mold and allowed to slowly cool. When this high carbon material is allowed to cool slowly, crack free castings can be made. Remembering this is helpful when welding cast iron: during and after welding, the casting must either be allowed to cool slowly, or should be kept cool enough that the rate of cooling is not important.

A critical temperature in most cast iron is about 1450 degrees F. When at this temperature, conditions that can lead to cracking occur. While the arc will heat the casting to temperatures above this level, it is important that the casting not be held at this temperature for long periods of time.

Electrode selection

If the part is to be machined after welding, a nickel-type electrode will be required. Use Lincoln Softweld® 99Ni stick electrode for single pass, high dilution welds. Softweld 55 Ni is preferred for multiple pass welds. Sometimes, root passes are put in with Softweld 99 Ni, followed by fill passes with Softweld 55 Ni. For welds where machining is not required, and where the weld is expected to rust like the cast iron, Lincoln Ferroweld® stick electrode can be used.

To Heat, or not to Heat

In general, it is preferred to weld cast iron with preheat--and lots of it. But, another way to successfully weld cast iron is to keep it cool--not cold, but cool. Below, both methods will be described. However, once you select a method, stick with it. Keep it hot, or keep it cool, but don't change horses in the middle of the stream!

Welding Techniques with Preheat

Preheating the cast iron part before welding will slow the cooling rate of the weld, and the region surround the weld. It is always preferred to heat the entire casting, if possible. Typical preheat temperatures are 500-1200 degrees F. Don’t heat over 1400 degrees F since that will put the material into the critical temperature range. Preheat the part slowly and uniformly. 

Weld using a low current, to minimize admixture, and residual stresses. In some cases, it may be necessary to restrict the welds to small, approximately 1-inch long segments to prevent the build up of residual stresses that can lead to cracking. Peening of weld beads can be helpful in this regard as well.

After welding, allow the part to slowly cool. Wrapping the casting in an insulating blanket, or burying it in dry sand, will help slow cooling rates, and reduce cracking tendencies.

Welding Techniques without Preheat

The size of the casting, or other circumstances, may require that the repair be made without preheat. When this is the case, the part needs to be kept cool, but not cold.

Raising the casting temperature to 100 degrees F is helpful. If the part is on an engine, it may be possible to run it for a few minutes to obtain this temperature. Never heat the casting so hot that you cannot place your bare hand on it.

Make short, approximately 1” long welds. Peening after welding is important with this technique. Allow the weld and the casting to cool. Do not accelerate the rate of cooling with water or compressed air. It may be possible to weld in another area of the casting while the previous weld cools. All craters should be filled. Whenever possible, the beads should be deposited in the same direction, and it is preferred that the ends of parallel beads not line up with each other.

Sealing Cracks

Because of the nature of cast iron, tiny cracks tend to appear next to the weld even when good procedures are followed. If the casting must be water tight, this can be a problem. However, leaking can usually be eliminated with some sort of sealing compound or they may rust shut very soon after being returned to service. 

The Studding Method

One method used to repair major breaks in large castings is to drill and tap holes over the surfaces that have been beveled to receive the repair weld metal. Screw steel studs into the threaded holes, leaving 3/16” (5 mm) to ¼” (6 mm)of the stud above the surface. Using the methods discussed above, weld the studs in place and cover the entire surface of the break with weld deposit. Once a good weld deposit is made, the two sides of the crack can be welded together.

post photo
tuckinlugs06   +1y

oh im sorry i dont own a chevy like that and wasnt fuckin sure it was cast or not thats why i asked...that must be your boy so your gonna talk shit for him huh
GraphicDisorder   +1y


---------------------------------------------Originally posted by TuckingLugs05oh im sorry i dont own a chevy like that and wasnt fuckin sure it was cast or not thats why i asked...that must be your boy so your gonna talk shit for him huh---------------------------------------------I think people thoguht you wanted to point it out that it was cast so you could tell him welding to cast was not a popular idea. If its not your reason, then so be it, it was very easy for some to draw that conclusion though.   But to clear it up, nobody at TBC is my boy, in fact I have even contacted them off the forum to warn them about an employee's past.  Im sure you thoght you had it all figured out though. Im sure if you keep calling people fags, and name calling it will get you a long way though.
ra156   +1y

so it is cast then?
FCKNLOW   +1y


I feel sorry for the people who run this site sometimes. Brandt I have a whole new respect for you after seeing the way you handle this, but me on the other hand, i can't hold my tongue any longer about this negative prick!

Tom (tuckinglugs05), I'm on SSM allot and this is not the first you have pulled this sh*t.  IMO it would be best if you were banned! People like you is what kills our culture, i have seen many threads where you tend to pick fights, make a smart*ss comment, etc.  If you can't say anything positive then  shut your f*cking mouth!!!!  TBC I'm sorry that i did this on your build up, but it had to be done. 

ra156   +1y

cast?
HarryBalls   +1y


yes it is cast^^^ And by following the guidelines posted......welding cast isnt a problem. We have done a few sets of honda spindles doing the same procedure and drove the piss out of them, problem free!   
TBCWORKS   +1y


HEY!!! Lets Just Squash All The Beef And Negativity!!! Enough Already!!! This Is A Thread About Our Shop Truck Build...Go Argue Somewhere Else!!! The question has been answered and i have posted literature on the topic. AdamTBC
gold_standard   +1y


Nice work guys.  I've seen that truck sittin' by your shop for a while.  Hope to see it at some shows soon.