Bull Heat Deflector Mod, improvement, etc.

[NinoRT700]

My deflector kept warping on the 700 so dealt with recteq and they sent me out a new one so I just finally picked up a steel plate to do this mod as soon as my new heat deflector shows up.
Just a few questions
Since it’s big thick piece of metal added
1. Does this create a big hot spot now?
2. Any effect on how high the temp gets?
3. Does the grill take longer to cool?
Also any negatives or extra stuff you can tell would be great. Thanks

 

[JGW]

I haven't noticed much difference. Note, I never shut the grill down until it's lower than 250, so it always takes a while to shut down after high temp cooks.

It may help with temp bounce back after opening the lid, but my high and low temps are the same as before.

Negatives.....it makes the deflector heavier.

 

[Zonktified]

This is exactly why it doesn't need to be stainless steel. The main goal is to provide a warp free deflector with something that can withstand heat. A $20 steel plate works great for this.

How's about aluminum? Asking since I have a spare plate around here somewhere...lol.

 

[chadinsc]

How's about aluminum? Asking since I have a spare plate around here somewhere...lol.

aluminum would probably be very close to melting.

 

[Partimewages]

I don't know how hot the fire pit gets but I can get my old 680 to nearly 475-500. That's how I initially clean everything before disassembly for a thorough cleaning. I have seen glowing red in the bottom!

 

[JGW]

How's about aluminum? Asking since I have a spare plate around here somewhere...lol.

Nope. Stainless steel and aluminum will react to each other negatively....causing galvanic corrosion.

 

[Greg Jones]

Aluminum will melt, at least it will in a Wyldside. Brand new set of GrillGrates on mine, last summer.

 

[JGW]

Wow....How hot did you get that grill?

I'm not sure what the melting point of aluminum is, but I think it's around 1100-1200 degrees.

 

[IPlayWithMeat]

Wow....How hot did you get that grill?

I'm not sure what the melting point of aluminum is, but I think it's around 1100-1200 degrees.

That’s correct. Pure aluminum has a melting point of 1220 F. In addition to the galvanic corrosion potential and the lower melting point, I question how much structural integrity it would add .

 

[Chevys10zr2003]

That’s correct. Pure aluminum has a melting point of 1220 F. In addition to the galvanic corrosion potential and the lower melting point, I question how much structural integrity it would add .

Also keep in mind that it turns to pure liquid at 1220°F. It becomes significantly weaker at temperatures way lower than that. A Google search suggests that aluminum loses half of its strength around 600°F. So just because it bent like that doesn't mean that it got above 1,000°F even.

 

[Greg Jones]

Oh it melted the grate. The next day I had to chip the aluminum slag off the inside of the grill just so the grates could be lowered completely.

 

[Zonktified]

wow...glad I asked! LOL

 

[Gotcha]

I did this same mod on my Traeger (some of you may have seen those pics I posted here) and just did it on my Bull. I really am not sure why the various makers do not spend a little bit more to build a heat deflector that doesn't warp, but that's neither here or there.

I know they say it doesn't really affect the grill, but to me it would seem more heat would come up on the higher end of the warp possibly creating a hot spot in that area. In any case, not a fan of the warped deflector, so I always fix it. I also think the extra steel slightly helps with bounce back as I am sure it retains more heat than the default metal.

Parts

1 - .25 steel plate (12.75" x 9.25) Note: Lowes sells a 12" x 12", and you can use that, but I ordered this one pre-cut from www.onlinemetals.com, mainly because I didn't want to cut the plate myself. They have quick shipping, but due to weight, packaging, etc. the shipping is almost as much as the plate (about $38 together, plate + shipping).

4- 5/16 x 3/4" stainless steel bolts, washers and nuts.

Do some quick measurements for where to drill the hold and bolt it on. If you have a welder, you can certainly weld it on. In the past, I have always used 5 bolts, but I am not sure it's necessary.

I'm going to burn it in before cooking, just to make sure the plate doesn't have anything left on it (cutting fluid, processing gunk, etc.).

I was looking through their site, do you still have the part number?
Also was it difficult drilling the holes?
Best Greg

 

[JGW]

I don’t, but it’s the custom cut .25” steel plate. Drilling is easy with a drill press, but use cutting fluid.

 

[BradBQ]

I don’t, but it’s the custom cut .25” steel plate. Drilling is easy with a drill press, but use cutting fluid.

Just finished doing this mod to mine last weekend. Highly recommend a drill press if it is an option.

 

[okie]

I did the same mod on a Traeger years ago for the same reason. Still going strong, no warp, etc.

I liked it so much....I did it again. LOL.

I have found that my 3/16" 9" x 9" mod is slower to heat up and especially slow going from high temp to lower temp (rarely do this anyhow). I think the heavy mod is like a heat sink, thus slow to accumulate and late to radiate the retained heat away. I had to adjust the "Offset" as a result of the altered temp response as well. I have two ideas to reduce the weight.
1. cut out a large central portion of the 3/16" plate i.e. 6 inch circle or square. I think the remaining piece will still be stiff enough to prevent warp.
2. Or, get a 9"x9" 1/8" thick SS plate to replace the 3/16" thickness. I don't think a flat piece is prone to warp as is a large formed diffuser does.
I am not equipped to cut out a piece from 3/16" and the local machine shops want $120/hr for their time. So will order the 1/8" (11gauge) 304 SS plate and substitute it and observe. More to follow---

 

[JGW]

I have not had any issues with it heating up, but yes the steel will hold more heat which helps with temp coming back up after opening the lid.

I never go from high to low so that’s not something I worry about.

 

[okie]

What's the lowest grade of stainless that you'd use to do the job? Just priced out 316 - 12.75x9.25x0.25 was $175. Don't want to cut corners too bad but want to be realistic.

Thank you for posting these instructions. I may try your modification. I've had my Bull for 3 weeks with about 7 cooks on it. Using the Full setting once for steaks. Cleaned out my foil and took a look at the Heat Deflector plate and it's already warped. I'm sure it doesn't make a huge difference but this is a bit concerning. How much worse will it get in a few months or a year? I would hate to call every few months for the next 6 years asking for a replacement.

RT people say it makes no difference unless it touches the drip pan and conducts heat directly into it. In fact I was told that while they no longer just replace the diffuser for warping, that they will send you another if you send pic showing it touching the drip pan. How can you take such a pic with them in place?? Not visible from above.

 

[Roaniecowpony]

Guys, the warping of these deflectors isn't because of "cheap Chinese" materials. The stainless steel used is a "cold rolled" sheet stock, formed in a "cold" or unheated condition, so as to prevent scale from forming on the outside and allow for direct use where a clean, scale-free surface is desired. The issue with "cold rolled" stainless steel or even other steels made this way, is that it creates internal stresses in the material. These internal stresses remain in the material until we heat them. Any cold rolled steel sheet can and likely would warp in our situation, regardless of where it's made.

 

[Roaniecowpony]

RT people say it makes no difference unless it touches the drip pan and conducts heat directly into it. In fact I was told that while they no longer just replace the diffuser for warping, that they will send you another if you send pic showing it touching the drip pan. How can you take such a pic with them in place?? Not visible from above.

Cellphone with the flashlight on. Flip the drip tray over and if the deflector has been riding on it, you'll see a mark.