Having difficulty maintaining lager temps

Am having a little difficulty maintaining lager temps.

I just brewed a Bohemia clone and the recipe says to ferment at 52 degrees for 28 days.

Here's the problem; our outdoor chest freezer ( we have a temp regulator on it) can usually hold the temp well when the outside temp is average at night.... 40 degrees plus. But it has been pretty cold here at night 29degrees in the am. And the chest freezer gets to about 40 degrees.

My question: what can I expect from this beer if the lagering temps vary from 40 degrees to 52 daily?

I know that there are devices out there that I can wrap around the fermentor to keep it warm, but irony have the time to buy one or even make one for that matter.

Any input would be greatly appreciated.

40 is pretty cold for even lager strains of yeast. I would insulate the fermenter as well as possible inside the chest freezer to maintain the beer temps more consistently. Wrap in sleeping bag or something similar.

Bigger question is: if you have a temp regulator on your chest freezer, why not bring it inside? Or at least garage where it might be warmer? Would make a perfect lager.

I assume you're talking about the effect of fermentation temps swinging, not lagering temps swinging, right?

I don't have first-hand experience, but everything I've read/been told indicates that you don't want to expose lager yeast to temperature swings. Recommended swing limits are a couple degrees, not a dozen. I'd find a way to stabilize, or delay brewing this beer until nature is more cooperative.