How to cut aluminum

[Brewsday]

My new-used brew station has 3 large banjo burners under 3 x 20 gallon Bayou aluminum kettles. The guy I bought it from "threw in" the 3 huge steamer baskets. My burners need wind screens. The burners are 9.5" diameter and 4.5" from the bottom of the kettle (seems like too far but VERY difficult to change...but what should it be if I get into that?). The kettles are 21" diameter and the steamer basket is 18" diameter. Roughly speaking it looks like I can get 3 x 4" to 4.5" "tall" rings from one basket. Then I'll notch the bottoms and they'll sit nicely in the burner bracketing.

What I want to do (pending feedback from you all) is slice one of the baskets into 3 rings for wind shields (and to help focus the heat column. )

My questions are:
1) how close to the bottom of the kettles should the top of the shields end up?
2) Is there danger of aluminum not handling the heat? (this is pretty thick aluminum). I figure the ring will be about 4"+ away from the burner on all sides.
3) How to slice the basket? I have handheld jigsaw with bi-metal blades meant to cut metal up to 1/8". I'm thinking of slapping together a jig to hold the saw and rotate the basket against uprights to get a nice smooth cut. I also have saws-all or circular saw (but no fancy blades and hate to buy for just this).

Thanks DIY-ers!

 

[casonso1]

any of those saws will cut the aluminum but i'd go with the saws-all, the jig saw would also work pretty good but the blade gets gummed up with the aluminum so use a rougher blade than a metal one and plan on going through a couple of them. the circular saw would give you the straightest cut and fastest but it will throw shavings everywhere so make sure you wear safty glasses and maybe even a face shield.

 

[Brewsday]

Sounds like a job for my chain sawin' headgear.

Thanks for the cutting advice.

Still wondering if aluminum will work for this shielding app?

 

[otiscampbell]

I have done what you are describing with an old piece of aluminum flashing which is likely much thinner than your basket. It was a windy day and it seemed to me that I was losing heat, grabbed that flashing and my tin-snips and voila! Insta-shield. It got hot for sure but never got to the melting point. Remember that when you are done brewing, aluminum won't glow red to remind you how hot it is! I should think the jig saw or sawzall would be fine for your application.

 

[Brewsday]

So, after much mental debate I decided to try the jigsaw first. Worked very well with a little prep.

1) Draw cut lines on the basket
2) Screw a wood arm onto an old stool to hold the basket for cutting.
3) Cut with bimetal blade, 24 teeth per inch, Rockwell hardness #8
4) Start from the bottom to preserve the top ring for rigidity later
5) Test first ring for fit, modify with notch to be able to slide it in
6) De-burr and smooth every cut along the way with flat file
7) Post finished pics to HBT

...by the way, I'm looking at the bottom slice and thinking I might use it to "diffuse" the flame to avoid scorching when I finally decide to step mash something.

It turned out to be pretty easy. Maybe this is "brittle" aluminum as gumming the blade was a non-issue...lots of aluminum dust to sweep up after

 

[insp79]

The heat shields look great. They should work great to help keep the paint on your brewstand. I have used a high-speed 90 degree grinder with a 2" cutoff wheel to cut aluminum. Make a cut line marker with masking tape. You might have to adjust your burner height closer to your kettles. I cut a horse shoe shape opening on one side to allow the burner venturi to be raised. Nice build!

 

[acidrain]

I can't believe you chopped up perfectly good strainer baskets for heat shields.

They do look really good though... nice stand!

 

[Brewsday]

Well 3 ALUMINIUM baskets came with the kettles/stand (craigslist) so I still have 2 and since they no longer fit in the kettle because of all the fittings and thermometers I figured I could spare 1. I will admit that, if I were into it, they'd make great BIAB accessories...with a hoist! Those are big baskets (20.8 gallon kettles).

Hey insp79, your comment about burner height is interesting. I tend to agree with you and one of the reasons I made these shields was to hopefully keep the heat more focused on the kettle bottoms. Unfortunately the builder welded the frame and bolted the burners then ground off the bolt heads (why = ???). My thinking is to cut off the entire burner frame, shorten the pieces it hangs by and bolt or re-weld. I'm no welder but I'm thinking of potentially changing to variable burner height "slots". Bottom line...I've been all over this forum and even the web and don't feel like I've found definitive answers to optimal distance between flame and kettle (yes, I've seen the pics of the different colored flames and know where the hot spot is). I've done significant searching and been unable to find a good thread on that topic...if anyone knows one please point me to it. A friend with a Blichmann set-up has about a 2" gap. Mines over 4".

Please advise me !!!