# 20gal build Finially DONE

Discussion in 'Reverse Flow' started by regularjoe, Jan 2, 2014.

1. ### regularjoeSmoke Blower

That is interesting. I will look into those pics and see how it works.

2. ### regularjoeSmoke Blower

My biggest hang up now is the exhaust.  I was going to go with a 2.5 inch pipe from the local auto store. I was thinking of making it shorter and going with 3in. Does 2.5 inch seem too small or as long as I keep the correct volume does it really matter. I used the chart Dave posted and I am getting with a 3in pipe I will be around 17 to 20 inches with a 2.5 I will be between 20 and 24. I am wondering if I did the math correct because I get a smaller number than Dave listed earlier.  Dave you add on a few inches due to air drag correct?  If so this may be how I get a smaller number.

Edit: I will be around 4 inches down the side of the cooking chamber. I will have side mount smoke stack just as seen in Daves Picture. So I am thinking a 3 inch pipe 20 inches long plus another 4 inches to make up how low it would be mounted down the side. That gives me a 3in 24 inch long exhaust pipe. I do not want to be too long and have it sweat back into the Cooking Chamber.

Last edited: Jan 18, 2014

4. ### regularjoeSmoke Blower

I seen Dave rounded up some numbers and said it was due to friction loss. So am I on the right track with my math. Feldons calculator is way different as expected. What is your opinion Dave? Thanks for the help.

Last edited: Jan 18, 2014
5. ### lendecaturalSmoking Fanatic

You are right, Dave adds to allow for friction loss. His experience trumps the calculator, stay with the 80 cu-in and use either 2.5 or 3, adjust the length accordingly and you will be fine.

6. ### daveomakSmoking GuruOTBS MemberSMF Premier Member

Joe, morning..... Volume of the exhaust is not necessarily the definitive criteria.... Height plays a differential pressure role in making the exhaust work properly.... Height is what makes a chimney work in a fireplace.... there is a balance that must be achieved....

Dave

7. ### regularjoeSmoke Blower

Cooking it out again.
Hit it with a wire brush on a grinder inside and out

9. ### regularjoeSmoke Blower

Finally nice and shiny. Boy this was a dirty job.

10. ### regularjoeSmoke Blower

Finally nice and shiny. Boy this was a dirty job. I still want to go over it with some dish soap or something.

11. ### regularjoeSmoke Blower

Test fit the lower cooking rack.

12. ### regularjoeSmoke Blower

Got the firebox welded up. We were not able to put the back on because it was cut a half inch out of square. The cutout for the fb/cc was a nice fit too. My metal guy is going to recut it and I hope to hit it again next Saturday.

13. ### ohdannyboyFire Starter

Hi Regularjoe. I was trying to keep up with all the conversation. I saw one part about you were thinking about clamps to hold the doors shut. I saw and used these on my build. They are destaco p/n 202 toggle clamps in stainless. They have a 200lbs hold down. They are really small and powerful. I found mine on eBay. You can find larger ones at harbor freight if you have one near by. Or order them online. I hope this helps.

14. ### regularjoeSmoke Blower

Thanks. I actually have four of those ready to go if I need them. It looks like I will be taking this weekend off.

15. ### regularjoeSmoke Blower

Got the rear on the firebox and welded it on.

Rolled it around on the stand to weld underneath.

16. ### regularjoeSmoke Blower

Drain install

17. ### regularjoeSmoke Blower

Got the RF plates installed. I kinda wish I would of made the sides a little bigger so it does overflow in not on even ground.

I need to know how important it is to have the breather straight across the FB/CC opening? Once I put the flange on the door I lost the space that I was going to use to put on a 1in by 4in breather above the door. I have where the flange overlaps marked with a white line. Can it just go on the front of the fire box/ smoker? If it is best above the door I will just add in a piece of steel plate and cut the door down some. I did not finish weld my flange on because I had a feeling I will need to shrink the door down. My breather for the bottom of the firebox will be on the front of the box.

Last edited: Feb 1, 2014
18. ### regularjoeSmoke Blower

I got the hole cut out and the sides cut for the plenum. I will be using a 3in pipe and will have to try to figure out how long to make it. My plenum box will be 4.5 x 4.5 on the top and the rear is 4.5 x 4 then it will angle down to the box from there. I am guessing to start with a 24in long pipe and go from there.

Last edited: Feb 1, 2014
19. ### regularjoeSmoke Blower

My neighbor took in a beef and he did not like how much fat was on the beef short ribs so he gave them to me to see if I would like to smoke them. 15lbs. I did some beef ribs before but I don't think they were short ribs. I did some reading on them in the beef section and will try them once I finish the smoker.

Last edited: Feb 1, 2014
20. ### regularjoeSmoke Blower

Picked up a set of used wheels for the smoker. Two swivel and two are stationary. ,The wheels hold air and are about 6 inches. I think they will go trough my yard pretty good. I will have a handle on the front that can also be hooked up to the tractor. Also brought home 8 pieces of 2x2x24 square tube and 4 30 inches pieces for the frame work.  It may be a little overkill but it was free scrap we had at work.

Last edited: Feb 1, 2014