Thoughts about a 12'' collar on a 20'' chest freezer?

[DlALTONE]

Hello,
I found a chest freezer to accommodate a fermenting bucket. But I need to build a 12" collar to make it taller. Would putting a 12" collar on a 20" high chest freezer be a good idea? The reason why I dont get a chest freezer with the correct height, is because than the width gets wider and I dont want a huge chest freezer for a skinny bucket (14sq x 28H) So Id rather get something that fits it as close to possible so I dont have so much dead space.
This chest freezer is 18sq x 20height. If I can successfully bring it up to 32 inches with a 12" collar, it will be close to perfect. I want to make sure theres no issues with this I may be overlooking (loss of temperature, stability, ext)

Thanks!

 

[msa8967]

How thick of lumber are you planning to use? Will you have a temperature control unit?

 

[TomSD]

Should be fine as long as you insulate it. Might need some circulation though to keep the temp even and the moisture down.

 

[Demfer]

Hey man, No worries.

I just finished my build with a collar height of about 11.25" and thickness of about 2.25. No need for extra insulation my temp is consitant throughout the keezer, perhaps just a 1-2.5 degree shift between the collar and the bottom of the unit. I simply wired a old 12cm PC fan to a cell phone changer and mounted it inside to circulate air to the collar portion. I will be able to fit up to 4 kegs once I move the tank behind the freezer.

 

[High_Iron]

Can you shed some more light on how you wired the pc fan? thanks