by Mechniki » 15 Jan 2019, 12:57
You could never use an engine that uses petroleum based fuel indoors, you may be able to use propane (thinking of indoor forklifts). I stopped considering making a 4 stroke engine/generator some time ago. A 2 stroke would be too loud. You could in theory if building your own frame, using the frame as part of the exhaust tube or box steel, bafflers, mufflers and re-direction so waste is pointed to the ground. But indoor you would need batteries.
However in recent years, combustion engines have become more refined largely due to motor sports. So you could make a small enough generator to fit in one battery box, and fit two smaller batteries in the other battery box. Whilst outdoor have the generator constantly charging the batteries, switch it off to go inside, use the batteries, then outside again restart the generator.
Incidentally replace one of the battery boxes with an aluminium/aluminum - as a 33cc chainsaw running for 7 hrs melts the plastic with it's exhaust.