I need to make some bends in an approximately 1'x1.5' sheet of 3/32nd acrylic

1) Will I deeply regret using my oven for this?
2) If no, around what temperature should I toss that bad boy in, in order to have it flexible enough for <90 degree bends, for say, 10 seconds?

I tried a heat gun with the first attempt, I didn't get it evenly heated over the whole run. Managed to get a nice crack at the one edge
I figure with the oven it should be more even and I can get at least one of the bends, approximately, with some foil underneath.

Thanks for any help

Maybe describing exactly what you are looking to accomplish might help.

A less than 90 degree corner is fairly vague. One problem you will run into by heating the entire piece is that the entire piece then becomes as flexible as the area you are trying to bend. You also have to accept that this type of material will have a radius in the bend. Trying to bend it too sharply will promote stress risers.

A good method I've seen used involved using a pipe and heat gun, with the heat blowing through the pipe. Heat the pipe first. Target temp was ~200. The whole thing was jigged up and the bend radius was 3/4" as I recall. The key was heating the bend evenly. The material was clamped horizontally and gravity did the work.

You could probably bend tighter using a different heat source like a wire heating element if you can control the heat. I wouldn't try for an inside radius tighter than the thickness of the material.

For context, we were making CNC router enclosures. I did the wood portions but kept my hands off the acrylic after making my own mess. My guy had experience with aquariums and I watched and listened. We did 6 enclosures and if I had to make another I feel confident enough to try it now.

You could try one of those portable infrared heaters for the house.
Place the plexiglass on a smooth surface, and heat it.
Pull it out and place it on your form.
You're going to have to test to find out what temp/time you need, so make some test strips to practice with.
When you get the right amount of 'droop', throw it on the form and let it cool.
Do a search on 'Canopy Forming' for aircraft, and you'll get a good idea of the process.

Yep, this is the way. Never used acrylic though, polycarbonate only. We built a box, form on bottom, suspend plastic over form, heaters over polycarbonate until it gets wavy then drop it on the form. We used CNC cut MDF forms though, with a vacuum.

I'd throw the acrylic in a brake and use a torch to get it hot, then bend it, if you are just trying to make straight line bends.

In the past I’ve used an electric griddle and had good good results making simple straight line bends. It’s been a long time though.

When I was in HS, we did a few projects in Shop class where we had to take slices of Plexi and often bend them.
We had a gadget that reminded me of really wide scale toaster, it was just kinda a frame that was maybe 36"W x 3" x 3" an line of wire that went the 36"s wide, (think heating element in a Toaster for bread).

We had a timer and after it heated up, you'd lay your Plexi on there for the required time, then using welding or other heat safe gloves, you picked it up and bent the plexi over a mounted 2x4s or 4x4s that were about 4' wide.
Seemed to work well.
Looked like something the Shop teacher found in a project book and made himself, vs a store bought unit.

I just had to bend up a piece for my wife at a 45. I used a heat gun, straight edge, and a vice

 Have you checked youtube for any tips or tricks to help you out with this ??

https://www.youtube.com/results?search_query=how+to+bend+acrylic



.

The folks I know who melt plexi in ovens have a spare one in their garage.  Their spouses do not like food with a plastic taste or smell.