Need a new base stack

[Birdland Sugarbush]

I have an evaporator I bought from a sheet metal fabricator a few years back. The base stack has rusted out and I'm looking for a new one. Not exactly sure where to measure from (see attached images), but it looks like it's around 22" x 6".

I've looked at a few sites but haven't been able to find one with these measurements. Any suggestions on how to proceed?

Thanks,
Chris

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[BAP]

Try emailing Chris at The Maple Guys who run this site, contact information is under the new equipment tab at the top. Another place is Bascoms Maple Farm,

[Sugarmaker]

Any good sheet metal shop should be able to fab you a stainless base stack. Might want them to get the dims with you to make sure it will fit. Then the opening for the top stack, and the height of the base stack. Should be about all you need.
Regards,
Chris

[markct]

They are pretty easy to make, I made mine with a 3ft brake from tractor supply

[jmayerl]

Local hvac shop. I had a heavy gauge galvanized transition made for $50

[maple flats]

Just make it 1/4" smaller than the inside measurements on that outer collar in each direction. SS is best, but heavy galvanized will last for several years if you store it between seasons under a roof someplace. A local tin shop will be far cheaper than any from a maple company. If you go with galv. get 18 gauge or heavier (lower numbers are heavier), if you get SS 20 ga or heavier will be OK. Then taper it to the top with a minimum 3' height and much better a 6' tall transition. While squared corners are not the norm, it looks like that may be a better choice for what you have on your arch.