Cutting and butt weld upper frame rail

[Paul New]

Going to front half a car soon and need to cut the upper bar about 12” - 18” behind the motorplate, I realize I need to butt weld and have piece of tubing inside minimum 3” inserted from both sides of weld and a rosette welds on both sides.My question I cannot find if I can do this but I do read “butt weld splicing upper frame rails to the shoulder hoop is permitted between the centerlines of the forward roll cage hoop and forward seat uprights. If butt weld splicing is used here, an interior sleeve is required, extending a minimum of 3” on each side of seam.”  I also see that “butt weld splicing of the shoulder hoop is also permitted in the rear center. If butt weld splicing is used here, an interior sleeve is required.”

[fuel749]

In the 2.4C spec page 3 #9, last sentence says all other components may be repaired by splicing, patching, clam shelling etc according to generally accepted aircraft repair procedures.

 I've spliced lower frame rails behind the motor plate and certified with no problems.  I've also seen cars with a splice half way between the forward roll cage hoop and the motor plate.  Couldn't hurt to be prepared to show the inspector that line though. 

[Paul New]

Excellent I must have missed that line! I assumed I was all good just wanted to ask a few people to verify!

[hemidakota]

Paul when my dragster was certified, I could not get a 6.0 cert due to the sleeve not being past the front roll cage tube. I had to weld up right tubes behind the front roll cage tube from the upright tube behind the roll cage that was between the upper and lower frame rails. I hope this makes sense. Next time I am at the shop I will get a pic of what I had to do. Kinda sucked due to chassis having a 6.0 cert on it when I bought it. The inspector drilled a hole in my upper frame rail to check it and yes I was kinda pissed about the hole but it is what it is.

[rooman]

Paul, sorry that I was not around to reply last week but we were busy getting ready for and going to Bowling Green. As noted already the splice deal is perfectly acceptable if done correctly. I did a shoulder hoop replacement on Paul "Nobody" Schultz's NT/F car when it was owned by Brad Green and joined it between the steering cross member and the rear end uprights. It has been raced quite a bit since then and passed tech last weekend at Bowling Green where Joe Lease was looking pretty closely at the fuel cars.

Roo