You've seen it done any many ways at VWB, but
check this out...
Capacity mod in action 1
Picture: WSM Capacity mod in
Picture 1: WSM
Capacity grate 1
Picture 2: WSM
Capacity grate 2
Picture 3: WSM Capacity grate 3
Picture 4: WSM
Capacity grate 4
Also as seen on Virtual
Weber Bullet - Increasing capacity expanding the
capacity of a WSM is nothing new. The object of this
modification was to solve several problems at once - not just
Problem 1 - The obvious, the capacity is not always
sufficient for competition or entertaining get-togethers.
Problem 2 - Yes there's a second grate but have you actually
tried using it?
Problem 3 - Ok, you've expanded capacity, but now what?
Here's the thing. Although there is a second cooking grate,
it rests below the top grate - obviously. Now what happens when
you need to access the meat on the second grate? You left off
the top - and set it where? Or you have a temp probe in the top
grate, now what?
This WSM modification build upon familiar ideas linked to
above - connected grates forming a cage - with some
new ideas for refinement.
What if you actually had someplace to put the cage when you
lift it out for access to the lower grates? Someplace where
dripping grease wouldn't matter - neither would the mop, spray
or rub make a mess.
It's simple - not only are the grates connected, but they
make use of the tabs that the top grate uses for resting the
cage on - how's that??? No worries about pulling out the
temperature probe, dropping meat, or making a mess.
Here's how I did it:
First off, I replaced the bottom cooking
grate with two coal grates. The lower food grates is
actually just a little too large to lift straight out of the
cooker - it needs to be tilted a little to get it out.
This wouldn't do for these mod because the cage needs to
left straight out.
Second, I used 3/4x3/4 L stock, mild steel as the vertical
bars. These I cut and shaped to the right size. Along with 1/8
inc cable clamps to fasten the grate gives just the right
The L stock help guide the cage into place without grates
hooking up on the tabs, nuts and bolts inside the body in this
Third, this is where I'd make a change. In the picture, you
see the bar cut at an angle - this was done to facilitate easy
entry of the cage into the body. Turns out, it's not needed,
serves no purpose, and actually complicates things.
Here's why - As you can see here, I've attached some channel
to the grate so that it can rest on the original tabs that the
top grate sits on - this is the magic of this mod.
If the bar were not cut at an angle, I could have a much
more elegant solution by welding a piece of that channel onto
the end of the bar - wallah. Instead, I have this clumsy
FYI - Here are the grate sizes and model numbers for your
information. The sizes listed are the correct sizes - Weber
insists that the 17.5 inch grate is 18 inches.
1 - Top: Part # 970601, 17-1/2" diameter - $12.99
3 - Bottom: Part #970701, 17" diameter - $8.30
1 - Charcoal Grate: Part #72601 15-1/4" diameter - $9.05