Search found 1968 matches
- Thu Feb 22, 2024 6:04 pm
- Forum: Grand Scale Railroading
- Topic: 48v battery chargers
- Replies: 15
- Views: 1563
Re: 48v battery chargers
So set up to accomodate two 7” dia forklift traction motors... Do the traction motors have wound fields and if so, are they brought out on separate terminals? If so, you could conceivably arrange the control circuits to produce transition for increased efficiency when motoring. Also, if the field...
- Mon Feb 19, 2024 5:38 pm
- Forum: Lathes
- Topic: New Knurling tool
- Replies: 17
- Views: 1738
Re: New Knurling tool
I became unhappy with the bump style knurling tool that came with the lathe. I searched the internet and found pictures of a "Hemingway" style scissor knurling tool. I liked it so much I designed my own from the pictures... Nice piece of work, and it doesn’t look too difficult to fabricate.
- Sun Feb 18, 2024 9:48 pm
- Forum: Grand Scale Railroading
- Topic: 48v battery chargers
- Replies: 15
- Views: 1563
Re: 48v battery chargers
...but why would I want a 1000 w unit, versus a 350 watt unit? The bigger unit will, in theory, recharge the batteries more quickly. That said, lead-acid batteries can be damaged if the charging rate is excessive. The electrolyte may start “boiling,” which will cause a loss of water from the elect...
- Sun Feb 18, 2024 6:38 pm
- Forum: Riding Scale Railroading
- Topic: Energy Rotary spool valve
- Replies: 21
- Views: 1243
Re: Energy Rotary spool valve
One ran away in MA many years ago. Owner got off with it parked and prime mover idling. Being held by "hydraulic balance" of the spool in spring loaded neutral and no brakes. It took off and was headed around the track, nobody on board. Even at idle, was going way too fast for anyone to c...
- Sun Feb 18, 2024 3:08 pm
- Forum: Riding Scale Railroading
- Topic: Energy Rotary spool valve
- Replies: 21
- Views: 1243
Re: Energy Rotary spool valve
You can get stopped, but it is not the best way to get there...but better than nothing...and is what many of the designs being sold rely upon. I can see a potential lawsuit waiting for the builder who elects to not provide mechanical braking in his/her units. All that would be needed would be a ru...
- Sat Feb 17, 2024 4:24 pm
- Forum: Riding Scale Railroading
- Topic: Energy Rotary spool valve
- Replies: 21
- Views: 1243
Re: Energy Rotary spool valve
Not sure how we would run out of fluid ? In the scenario described by Bill, the pump, being held stationary by the not-running prime mover, will look like a blockage—the pump’s inlet and outlet are sealed from each other—and the motor will “suck a hole” in the oil, possibly entraining air into the ...
- Sat Feb 17, 2024 4:16 am
- Forum: Riding Scale Railroading
- Topic: Energy Rotary spool valve
- Replies: 21
- Views: 1243
Re: Energy Rotary spool valve
Properly implemented, the motor then becomes the pump, and by reversing the valve position restricts the flow out of the pump and becomes a brake....until you run out of fluid.. What do you mean by “properly implemented?” It sounds as though you are talking about “plugging” the propulsion. Doing ...
- Fri Feb 16, 2024 8:19 pm
- Forum: Riding Scale Railroading
- Topic: Energy Rotary spool valve
- Replies: 21
- Views: 1243
Re: Energy Rotary spool valve
Geochurchi wrote: ↑Fri Feb 16, 2024 5:38 pm ...none have brakes they rely on feathering the valve for control.
...which will fail if the prime mover quits running. Not good if on a grade with a train full of passengers. That’s why I have brakes on my locomotive and its control (riding) car.
- Fri Feb 16, 2024 5:10 pm
- Forum: Buy, Sell, Trade, Wanted, Free!
- Topic: SB chucks rotary table and misc.
- Replies: 12
- Views: 943
- Fri Feb 16, 2024 5:05 pm
- Forum: Riding Scale Railroading
- Topic: Energy Rotary spool valve
- Replies: 21
- Views: 1243
Re: Energy Rotary spool valve
Assuming the pump is not operating and we are in the parked position, Valve is in the center position should , should we still be able to roll the locomotive ? The subject valve, as I earlier explained, is “open-center” when in neutral... ...the load itself will not be driven or restrained... In ot...
- Fri Feb 16, 2024 4:49 pm
- Forum: Grand Scale Railroading
- Topic: 30 amp alternator
- Replies: 6
- Views: 704
Re: 30 amp alternator
If you are using a Delco-Remy as shown in @Steggy’s post, (looks like a 60A), you can get a regulator that requires low rpm to excite. Actually, it’s a 30 amp alternator, modified to reduce its maximum output to 25 amps, with the regulated, light-load voltage set to ~13.5 maximum. The reduced-volt...
- Thu Feb 15, 2024 8:44 pm
- Forum: Riding Scale Railroading
- Topic: Energy Rotary spool valve
- Replies: 21
- Views: 1243
Re: Energy Rotary spool valve
don’t quite understand the drawing What you are seeing are ANSI fluid power symbols . Ports A and B are the load, P is the discharge from the pump and T is the return line to the oil reservoir (tank). The object below the valve spool schematic is the internal relief valve. If it cracks, it divert...