Just another ST50 build

[RADFAB]

Hey guys my name is Drew and I've been reading and taking in everybody's builds for the last couple years and finally finished my rig which I'll post pictures of in a bit. Just another sore thumb ST50 build to satisfy the inner gear head in me. Started right up 2nd or 3rd try just needed to get fuel right and she was up and about. I'm having a little bit of trouble with oil aeration. I assume there will be some but I feel like I have more than I would like. I have incorporated a deaeration plate on my oil drain but it may be of subpar design for all I know. Any advice and help would be much appreciated. Thank you!


here's a picture of the deaeration plate I have in question

[racket]

Hi Drew

Is the plate flat or dished like the mesh cover ??

What actual size is the plate ??

How does the oil discharge across the plate ??

Also check that you have plenty of clearance between plate and oil level in tank as the clearance changes when running .

Cheers
John

[RADFAB]

The plate is dished just like the mesh cover, I had figured both would aid in the deaeration. that plate is about 2 inches across fits perfectly on the inside on the mesh screen. How much rise should I expect when running. Here is some pictures on the build and the oil drain. The oil just goes straight down. 

[racket]

Hi Drew

2 inch is pretty small and with the oil discharging directly onto its dished surface , everything will want to go straight through .

How much air is coming out of the tank breather when running ??

Its a big turbo , theres lotsa oil flow , I'd be using a flat plate of 6"X 6" size with no holes where the oil drops onto it , holes only once its started to spread out horizontally , or have the oil discharging across the plate from an elbow in the drain plumbing .

We need a couple of inches clearance between oil level and plate , 1 inch minimum .

Cheers
John

[RADFAB]

Sounds good thank you sir. Also to I want to be able to spool her up by any other means other than the leaf blower. Even though it's easy and effective, I really want to hear that initial run up of the turbine without that blower screaming right beside me. I was first going to try a router as I've seen others do, then realized the ST50 is a reverse rotation unit. Possible somehow the router motor can be reversed? Air impingement would be neat but not sure I want to go with the scuba tank. I read somewhere on here racket that you used an oxygen tank from a torch setup which I do have. What would be my plumbing setup if I were to go with a setup like that if you think that's a feasible route? I also have a 175 psi 80 gallon compressor in the shop if that could be utilized at all since my rig is stationary anyways. Just tossing around some ideas.

Thanks, Drew

[jetric]

Hi Drew,
Use one of these,

www.ebay.co.uk/itm/154470244129?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=2RbBY9arR_C&sssrc=4429486&ssuid=dhvoJXG-RcC&var=&widget_ver=artemis&media=COPY

Richard S.

Nov 4, 2023 11:17:05 GMT -5 RADFAB said:

Sounds good thank you sir. Also to I want to be able to spool her up by any other means other than the leaf blower. Even though it's easy and effective, I really want to hear that initial run up of the turbine without that blower screaming right beside me. I was first going to try a router as I've seen others do, then realized the ST50 is a reverse rotation unit. Possible somehow the router motor can be reversed? Air impingement would be neat but not sure I want to go with the scuba tank. I read somewhere on here racket that you used an oxygen tank from a torch setup which I do have. What would be my plumbing setup if I were to go with a setup like that if you think that's a feasible route? I also have a 175 psi 80 gallon compressor in the shop if that could be utilized at all since my rig is stationary anyways. Just tossing around some ideas.

Thanks, Drew

[jetric]

Or one of these,

www.ebay.co.uk/itm/175892208609?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=dPXUYVFRTle&sssrc=4429486&ssuid=dhvoJXG-RcC&var=475308621942&widget_ver=artemis&media=COPY

Richard S.

Nov 4, 2023 11:17:05 GMT -5 RADFAB said:

Sounds good thank you sir. Also to I want to be able to spool her up by any other means other than the leaf blower. Even though it's easy and effective, I really want to hear that initial run up of the turbine without that blower screaming right beside me. I was first going to try a router as I've seen others do, then realized the ST50 is a reverse rotation unit. Possible somehow the router motor can be reversed? Air impingement would be neat but not sure I want to go with the scuba tank. I read somewhere on here racket that you used an oxygen tank from a torch setup which I do have. What would be my plumbing setup if I were to go with a setup like that if you think that's a feasible route? I also have a 175 psi 80 gallon compressor in the shop if that could be utilized at all since my rig is stationary anyways. Just tossing around some ideas.

Thanks, Drew

[richardm]

Hi! If your router motor is of the 'universal " type it can be driven by either ac or dc current. Two ways to reverse it.
If you opt for ac current then interchange the connections from the stator to the brushes. This might involve some soldering.
You can also use a bridge rectifier of the correct voltage and amperage capacity to get dc current end simply reverse the dc polarity.

Another idea, since you have a big enough compressor would be using the motor from an air tool such as a die grinder. Some models are reversible such as this one.

www.tptools.com/AIRCAT-1and4-Reversible-Straight-Air-Die-Grinder,9439.html

[RADFAB]

Hey Richard S. the brushless motor is a good idea just they are all over the place with price and power. Any idea what the power output of the motor would roughly have to be? Richardm this is the router, it does have brushes so does that mean its of the universal type? It would be a cheap route if it has the power to get it up to speed. It's 11a 2hp 28000 rpm no load. 

www.harborfreight.com/power-tools/routers-cutout-tools-lathes/routers-cutout-tools/11-amp-fixed-base-router-68341.html

thanks, drew

[jetric]

The only way you can change the rotation of a universal type motor is to swap the polarity (interchange) connections for the stator windings.
If you rectify the ac to dc then reverse the input polarity to the motor it will still rotate the same way, you have to change the polarity of the stator windings to get the motor to run in the opposite rotation. Also be careful when rectifying ac to dc because you will be removing the RMS by rectifying the ac 110v which will be dc 156v after rectification.

Richard S.

Nov 4, 2023 14:03:41 GMT -5 richardm said:

Hi! If your router motor is of the 'universal " type it can be driven by either ac or dc current. Two ways to reverse it.
If you opt for ac current then interchange the connections from the stator to the brushes. This might involve some soldering.
You can also use a bridge rectifier of the correct voltage and amperage capacity to get dc current end simply reverse the dc polarity.

Another idea, since you have a big enough compressor would be using the motor from an air tool such as a die grinder. Some models are reversible such as this one.

www.tptools.com/AIRCAT-1and4-Reversible-Straight-Air-Die-Grinder,9439.html

[richardm]

Oups! You re right! my thought drifted away toward a permanent magnet motor. Any ways rectifying is the long route crisscrossing the brushes connection is simpler.

Now in my opinion a 2hp router at 28K rpm is plenty enough power to start your engine.

But this things are usually over rated: 1 "real" hp= 745 watts plus inefficiencies ( or losses) so you can account about 900 watts for every horsepower. Just check on the motor plate.

Now look at your router motor. An universal motor will have what looks like a slotted copper ring at one end of the shaft and should make some tiny blue sparks when running It also has two tiny carbon brushes making contact with that copper ring.

Chance are pretty good its an universal motor unless it is a recent and expensive brushless router

[jetric]

You need to use a brushless inrunner motor in order to get the high rpm but you have to use a low kv motor in order to balance out the high rpm with some torque (anything below 960kv) these motors are capable of producing high hp for there size (above 8hp for some) but the down side is there expensive (especially the controllers) and they draw high currents.
Andy M used one to start his turbine bike, I'm sure there's a video of it starting up somewhere on YouTube.
Brushless outrunner motors produce more torque but the larger size ones generally top out at 10,000rpm on 24v.
I would try reversing the polarity on you field windings of your router motor first, if that's unsuccessful then go the brushless route.

Richard S.

Nov 4, 2023 15:15:55 GMT -5 RADFAB said:

Hey Richard S. the brushless motor is a good idea just they are all over the place with price and power. Any idea what the power output of the motor would roughly have to be? Richardm this is the router, it does have brushes so does that mean its of the universal type? It would be a cheap route if it has the power to get it up to speed. It's 11a 2hp 28000 rpm no load. 

www.harborfreight.com/power-tools/routers-cutout-tools-lathes/routers-cutout-tools/11-amp-fixed-base-router-68341.html

thanks, drew

[racket]

Hi Drew

Yep , you'll be needing a couple of horsepower.

Personally , I'd stick with the leafblower if it works OK , its non contact so doesn't disrupt rotor dynamics , its simple to use with no construction of mounts etc , inexpensive as it can be used as a leafblower , mine has had >20 years of regular use , theres no need for batteries , chargers etc etc .

I'd go back to a leafblower if I could find one powerful enough to start my engine.

Cheers
John

[jetmanjoe]

I got myself a milwaukee leaf blower. The front long black cone pulls off and you just have the main body with fan by itself 

[racket]

OOPS , sorry to tell you , but it looks like that blower has an axial fan rather than a centrifugal compressor wheel , axial fans don't cope with backpressure of the sort we exert whilst trying to spoolup our engines , you may need to be very careful with how you apply the blower so that it doesn't go into surge and lose all pressure supplied to the engine , we need both air volume as well as pressure to force the air through the various restrictions within our engines .