Smoker Pit door sprung when cut.

[Darrel]

I need help ( as usual )
I am in the process of building a trailer mounted BBQ/Smoker Pit.. I am making it out of pipe.

1/4" thick
18" diameter
65" long ( Cooking Chamber )
28" long ( Fire Box )

My probelm is when I cut out the doors the pipe sprung a little , the cooking chamber doors arnt that bad , but the top fire box door sprung alot..
I cut the doors out with Zip Cut blades on my grinder , worked great..

I have heard of a fix that consists of running a few beads along the inside of the door to pull them back into shape. Does this technique work ?? If so which direction do I run the beads ??

The doors sprung at the bottom , the top where the hinges are are sitting nice..

Anyway here is my website with a few pic's.. Im sorry I dont have any closeups of my problem

www.mts.net/~darrelb

Thanks in advance..

[david_r]

Darrel,
I use my welder to pull bearing races when they are in too tight or I can't get a good purchase on the back for removal. A bead around them lets them drop out when cool.

You'll have to weld along the bow to get it to pull in. Most of the pull will be along the length of the weld. Think of it as a string on a longbow to get an idea of which way it'll bend. Of course, you're dealing with a piece of curved metal to begin with, so you'll have some forces to contend with that'll take a few tries to work out.

You may also be able to weld some bracing to hold the door in place, then heat along the now stressed area and allow to cool, cut the bracing out and check the results.

[fatfrank]

Darrel, try to get some upclose photos showing exactly how the door is sprung. A picture is worth a thousand words. I have built a few BBQ pits and have corrected problems like yours in the past. Welding a bead to realign the door sounds very simple, but is pretty crude at best. You may end up making the problem worse, or fixing one problem and making two. One of the best ways I have found to fix the problem when working with 1/4" pipe is cutting the hinges off and laying the door on the ground or on some RR track and pounding with an 8lb sledge.

[Tucsonshooter]

Darrel
I recently completed a pit that the door sprung on one side when I cut it out. I used an abrasive blade in a skil saw to cut it out. To get the door to line up again I used a combination of laying beads, bar clamps, and a big F*@#ing hammer. For the finishing touch I tweaked the door trim (astragal) to remove small gaps between the door and body.
I think David_r described it well about "pulling" the door by laying in beads. Tonight I'll post a photo of the beads I used to tweak the door on my pit.

Good luck

[trashcan]

The way I kept mine from springing alot when cut was to have a big bonfire with the pipe as the "guest of honor" It cooked in a big pile of brush and old cedar shingels for about 6hrs then was allowed to cool over night/morning. When I cut it got a really small ammount of warpage and was able to use the BFH to get it how I wanted it.I think that the lid removal/BFH approach with a nice astragal would be the best way to go(BTW, very nice pits Darrel, Fat Frank , and Tusconshooter). Thump On!!!

[Bolt]

I know it is too late for some of you, but for future references, and other people reading, when you cut the doors out of the main piece, do not cut them out completely. Leave a few spots on each side of the door intact, and then let it cool. Weld on your hinges next, and then cool completely, and then cut the last little bits off. That way your door will be straight, it will be on square, and alot of extra work will be spared.

[Tucsonshooter]

Bolt
I did that. It sprung anyway.

[NewStuff]

I am pretty sure that if you had the end caps welded in place, the degree of warpage would have been greatly reduced. The ends open as shown give very little support. My thoughts, could be wrong

[NewStuff]

I am pretty sure that if you had the end caps welded in place, the degree of warpage would have been greatly reduced. The ends open as shown give very little support. My thoughts, could be wrong

[Ken M.]

When you say sprung, I take it you mean the radius increased? I was thinking that if you have a torch, you might be able to run a few parallel heat lines on the inside along the length starting at the bottom where the problem is. You can mist behind the flame to control the excess heat. This will tighten the radius of the bend. You would be suprised how much control you can have flame bending and straighting with a torch.

[fatfrank]

When you say sprung, I take it you mean the radius increased? I was thinking that if you have a torch, you might be able to run a few parallel heat lines on the inside along the length starting at the bottom where the problem is. You can mist behind the flame to control the excess heat. This will tighten the radius of the bend. You would be suprised how much control you can have flame bending and straighting with a torch.

Ken M, I do agree with you that some people can control a rosebud and get the results they want. I found that I can get pretty close sometimes using the torch or a few 6011 beads in the right place, but I aslo potatoe chip the crap out of it sometimes. I think the BFH is the way to go for the novice. Get some hearing protection on when you get out the BFH, if not your ears will be ringing for a few days.

[Tucsonshooter]

Sorry, I'm a little late posting this.

On my BBQ door, it sprung more on one side than the other. I pulled it in with a pipe clamp and then layed a few inches of bead. Then I would check it and determine where to hit it next. It took about an two hours, but I finally got it tweaked back in line.

Heres a photo

[Darrel]

Thanks for all the reply's.. The picture helps alot also.. I think the answer is heat and a BFH...

I found something interesting though .. My pipe is seamed pipe , on the Fire box ( with sprung door) the seam is right across the door... And on the Cooking Chamber the seam is almost at the opposite side of where I cut the doors...and they didnt bend....

Possibly a lesson ???

[Tucsonshooter]

I purposely put the seam of my tank down, which puts it at the center of the clean out door of the fire box. An angle grinder will smooth that seam out just fine.

This last weekend I did three whole chickens and a test pan of salmon. The chickens were great and the salmon didn't last 10 minutes. Seriously good.