Gallery, Projects and General > Project Logs

David Goodfellows - Brassy Babe: My first engine build.

<< < (2/5) > >>

spuddevans:
Looks good Chris, :clap: :clap: I'm sure you'll have it running on air in no time at all, and I have to tell you that is the greatest feeling  :D


Tim

raynerd:
Hi all, any advice welcome - it needs some fine tuning and I am struggling!

OK, well finished off Brassy Babe and unfortunately it isn`t working properly! Not really a surprise to me, but now I`m trying to find out what is wrong. I have hooked it up to the compressor and it is certainly working to a degree - you can certainly see it is gaining something from it!

I feel like it is the flywheel that isn`t creating enough momentum to pull it though the next phase of the cycle. If I turn the whole thing upside down I definitely get a few seconds run time out of it. I also notice that my piston is not uniform and must taper, the pressure is 100% forcing the cylinder up but then the air escapes from it at the top rather than through the outlet!

Any advice as to which to "debug" first - I feel that if I could modify the flywheel to spin more freely it would run as it is right at the top of the crank where it ends up stopping, the flywheel isn`t driving it back around. Then again, is the air escaping from the cylinder an issue, although this is certainly at the top of the cycle at the same point that it would be escaping from the outlet anyway.

Advice welcome. I`m getting some action so i`m not totally gutted.... yet

Chris

sbwhart:
Hi Chris

One thing you may try is to get each element running freely, work on the flywheel first get that running free, connect it to the crank get the crank running free round the crank pin, then get the piston running free in the cylinder. Lap each part in with toothpaste or brasso, make sure you've got no tight spots, the smallest burr will have an effect, clean round the edges with a scalpel, these small engines havn't a lot of power so the slightest thing can stop them.

Keep trying it sounds like your very close it took me a couple of days to get my first wobler running.

Good luck

Stew

raynerd:
It is running but won`t run properly sat on the stand - even if you just raise the back up a little it will run but if you turn it upside down it really fly around!!!

Any advice as to why it isn`t running correctly the right way up would be greatly appreciated.

raynerd:
Well 10 minutes later and it is running  :)
But with an issue  :(

Advice would be greatly recieved...





This video actually exadurates it a little - On the base it won`t run, or 1 or 2 revs max. If you just raise the back up a few mm it runs! Turn it upside down and it flys around!!

Why isn`t it running level on the base?

Navigation

[0] Message Index

[#] Next page

[*] Previous page