Search found 628 matches

by BigDumbDinosaur
Tue Sep 18, 2018 2:43 pm
Forum: Riding Scale Railroading
Topic: LOUD diesel horns?
Replies: 16
Views: 2494

Re: LOUD diesel horns?

Just purchased a 12 volt horn on Ebay...inquired about the pitch...The response was 105 to 110Hz. 105 to 110 Hz seems unlikely—110 Hz is A2 on the piano. A locomotive air horn (aka "air trumpet") is acoustically modeled as a stopped pipe. The fundamental frequency of a stopped pipe corresponds to a...
by BigDumbDinosaur
Sun Sep 16, 2018 11:32 pm
Forum: Live Steam
Topic: Sharp Corners
Replies: 2
Views: 315

Re: Sharp Corners

Pretty cool. I wonder if it would be worth the trouble in the future to make a mold and cast those braces. It seems you had to go through quite a bit of work to get to the finished product.
by BigDumbDinosaur
Sat Sep 15, 2018 2:31 pm
Forum: Riding Scale Railroading
Topic: Electric motors
Replies: 3
Views: 172

Re: Electric motors

You didn't say what type of motors these are. If they are permanent magnet types they will all run at approximately the same speed for a given load and voltage, but will not produce real high starting torque. If wound-field motors, it would depend on whether series-wound, parallel-wound or compound-...
by BigDumbDinosaur
Wed Sep 12, 2018 5:12 pm
Forum: Live Steam
Topic: Polishing inside of 0.25" cylinder?
Replies: 8
Views: 466

Re: Polishing inside of 0.25" cylinder?

I am converting the crosshead pumps on my 1-1/2" scale American from "displacement" type with a packing glad (which always leaked and were nearly impossible to tighten up) to O-rings set in the plunger to act as piston rings. I have done O-Rings for piston rings but in cast iron cylinders that I co...
by BigDumbDinosaur
Sun Sep 09, 2018 7:15 pm
Forum: Live Steam
Topic: Understanding types of copper?
Replies: 26
Views: 935

Re: Understanding types of copper?

Fender wrote:
Sun Sep 09, 2018 9:25 am
A pipefitter once told me (tongue in cheek) that the definition of pipe is “that round stuff with a hole down the middle”!
Complicating matters, steel houses offer pipe-size mechanical tubing. :D
by BigDumbDinosaur
Thu Sep 06, 2018 9:32 pm
Forum: Riding Scale Railroading
Topic: Small Diesel engines for motive power
Replies: 26
Views: 1532

Re: Small Diesel engines for motive power

Bill Shields wrote:
Thu Sep 06, 2018 8:11 pm
another way to 'eliminate the lawn mower effect' is to put steam through the exhaust :shock:
Steam-powered Diesel locomotive. Now there's a novel concept. :D
by BigDumbDinosaur
Thu Sep 06, 2018 9:30 pm
Forum: Riding Scale Railroading
Topic: Small Diesel engines for motive power
Replies: 26
Views: 1532

Re: Small Diesel engines for motive power

I've got a piece of 8x6x3/8 rectangle tube about 15" long that will be my "fuel tank" muffler. Exhaust will flow into the top, make several passes through some tubes and perforated metal packed with rock wool, then exit into the stack. Here's an exhaust silencer I built for a friend's Kohler-powere...
by BigDumbDinosaur
Thu Sep 06, 2018 9:17 pm
Forum: Grand Scale Railroading
Topic: 12" working railroad
Replies: 321
Views: 30438

Re: 12" working railroad

I was having a little brainstorm today, regarding my air plumbing and 12v air compressor location. As it was, I'll need to run the air from the locomotive to the riding car, then from the brake control back to the locomotive and rolling stock. This meant a second air hose between the loco and ridin...
by BigDumbDinosaur
Tue Sep 04, 2018 12:42 pm
Forum: Grand Scale Railroading
Topic: 12" working railroad
Replies: 321
Views: 30438

Re: 12" working railroad

Question for you guys, are push lock fittings and plastic tubing acceptable for the air brake lines, or should I go to the extra effort of running hard lines under my frames? My brakes will be "sprung on", and I'll apply air to release them so it would be safe in case of a line failure. My recommen...
by BigDumbDinosaur
Thu Aug 30, 2018 2:50 pm
Forum: Riding Scale Railroading
Topic: Electric wheelchair motors
Replies: 37
Views: 1287

Re: Electric wheelchair motors

Ohhh I could spend way too much money on that tolomatic stuff! You could. The brakes on my F7 and the control (riding) car are Tolomatic calipers running on cut-down go-cart rotors. There are two calipers on the locomotive and four on the control car. That's a couple hundred dollars in brake parts....
by BigDumbDinosaur
Thu Aug 30, 2018 1:19 am
Forum: Riding Scale Railroading
Topic: Electric wheelchair motors
Replies: 37
Views: 1287

Re: Electric wheelchair motors

Interesting, so a driveline with U-joints, and right angle drives of some type on each truck? Those right-angle drives appear to be Tolomatic gearboxes . You would use an arrangement like this if a single traction motor is to be mounted inside the locomotive. One disadvantage of this design is the ...
by BigDumbDinosaur
Tue Aug 28, 2018 12:38 pm
Forum: Riding Scale Railroading
Topic: Electric wheelchair motors
Replies: 37
Views: 1287

Re: Electric wheelchair motors

I think that one downside is that the gearboxes can be worm drive, so when you stop the motor, it comes to a halt - there is no coasting. Not necessarily. A worm gear drive using a multi-start worm may be reversible. In a worm drive, the gear ratio is defined as N ÷ S , where N is the number of tee...