4-3/4" VS 5" gauge Sweet Pea

[ironhorseriley]

Hello everyone,

My question to this knowledgeable group: are there instructions or direction in Jack Buckler's book:
Build Your Own Steam Locomotive "Sweet Pea" as well as the plans from Blackgates, concerning building in 4-3/4" gauge instead of 5" gauge as it is designed?

Thank you all,

Jim

[gwrdriver]

Jim,
This doesn't answer your question, but typically the modifications required for building to 4.75"ga, when that's possible, are included on the drawings for popular designs, and I would consider Sweet Pea to be a very popular design. Even if they aren't the modification is fairly straightforward. It's the inside cylindered locomotives which usually can't be re-gauged, or at least not without great difficulty.

[Bill Shields]

you could do a LOT worse than building a Sweet Pea.

They are very good running engines -> more fun than a barrel of ....<fill in the blank>.

[Builder01]

I am currently building a Super Simplex. It is a British style 0-6-0 tank engine. As designed, it is 5" gauge. I too, am re-gauging it for 4-3/4" track. I am slightly familiar with Sweet Pea. It is a very popular locomotive. With outside cylinders and valve gear, re-gauging for 4-3/4" is not too much of a problem. You will simply have to make the frame spreaders 1/4" narrower than specified. I did a bit of backward calculating using the IBLS standards for 4-3/4" track, and as it turns out, narrowing all the spreaders by 1/4" was all that was needed. Of course, I also had to shorten the axles. I have finished my frames, axles and wheels. It fits just fine on standard 4-3/4" track.

I kept the buffer beam and drag beam exactly the same width as drawn, so, the overall width of the locomotive will remain the same. This will cause the running boards to be widened by 1/8" each to reach the corner of the frame. The bottom of the fire box will also need to be narrowed to fit between the frame. With a narrower fire box, I slightly reduced the bore of the cylinders. Also, the saddle will require a little modification to fit properly between the frames.

I also kept everything else above the running boards the same width as originally drawn. This allows you to use some of the laser cut parts for the cab and tanks. It also allows for everything to fit into the cab as drawn. Many laser cut parts are available for the Super Simplex, I'm sure the Sweet Pea is no exception. If you can, get whatever is available for the laser cut parts, it will save you a ton of time. The steel parts, like rods, are not expensive and very much worth getting. The brass parts for the cab are not cheap and I am waiting to save up for them when it is closer to the time that I need them.

I have dealt with Blackgates several times, they are good folks, but, sometimes it may take a while to get your order together for them. They respond pretty well with email. When your order is packed, shipping time is usually only about a week.

David

[super7b]

On the subject of Blackgates, I endorse all the good things about them Builder01 said, but especially about the time factor, we tend to call them "Blackgates Eventually", no disrespect intended, others in the business of model engineering supply are a lot quicker, you pays your money, you takes your choice!

[Fred_V]

go here:
https://groups.yahoo.com/neo/groups/swe ... opics/1040

[ironhorseriley]

Thanks, everyone. It sounds like not too much of a problem overall. As a newbie contemplating building a locomotive someday, that the Sweet Pea for 4-3/4" (5") gauge & the Sweet William for 7-1/2" (7-1/4") gauge is one of the best over all beginner projects and very good basic, solid locomotives to maintain and operate. I do not live anywhere near a club so as much as I like the size advantages of 7-1/2" narrow gauge scales, I am starting to lean more toward 4-3/4" narrow gauge scales for the practicality of space and possible traveling.

[Benjamin Maggi]

Having read the Sweet Pea book all the way through at least 4 times, I am pretty confident that you could build it in 4.75" gauge. It is extremely fortunate that it has outside (Hackworth) valve gear which doesn't clog up the inside of the frame, and it only has a single-axle water pump (instead of the dual axle one on the Sweet William) which means a single eccentric on one axle only. Moving everything closer together by 1/4" shouldn't be a problem.

WARNING: the Sweet William engine's sideframes are spaced apart such per the plans that there is very little clearance between the backs of the wheels and the frame. I adjusted this as noted on my build log. If you take the Sweet Pea and narrow the wheels for 4.75" instead of 5, make sure you narrow the frame enough for the wheels to clear. It is super easy, but making the axles 1/4" shorter won't be enough. I have actually seen the Sweet Pea plans as friend had them at one time, but I cannot remember if they were dimensioned for both gauges. A quick email to Blackgates Engineering would confirm this.

If you go down that road, you will need to either make the valve gear reach rod slightly different so that it is bent to reach the new correct location, or make it identical to plans and just take a full 1/4" off the other side of the engine. Either way is fine.

As for traveling, I don't know about AR but I would suggest you look around and see what clubs are near enough that you might consider running at.

[Benjamin Maggi]

I have dealt with Blackgates several times, they are good folks, but, sometimes it may take a while to get your order together for them. They respond pretty well with email. When your order is packed, shipping time is usually only about a week.

I agree that Blackgates are great to work with. My only caution as someone living in the US is that shipping costs are outrageous (perhaps that is the standard all over the world?) and unlike American vendors I would not suggest you purchase bits and pieces as time and money allows. Either order the parts you need up front and pay one shipping amount or expect the cost of shipping to sometimes exceed the value of the parts ordered.

It is because of this that I am fabricating much of my engine from stock, or utilizing American engine castings when possible. Nothing against Blackgates, but I cannot afford to pay the postage.

[ironhorseriley]

Thanks, Ben. I agree with your approach. It is funny I just now stumbled upon a similar group of posts on the same subject matter from 2011:
http://chaski.org/homemachinist/viewtop ... =8&t=89425

Either way the nearest clubs are 4 hours away: Oklahoma City, 7-1/2" gauge only & several groups (1 or two clubs & 2-3 private tracks) in the Kansas City area, one or two with 4-3/4" gauge. I have a friend in Wichita who along with a very small group of like minded friends all with their own private tracks, one of which is 4-3/4" gauge. Southwest Missouri and Arkansas has or had 2-3 private tracks, but no clubs, all 7-1/2" I think, still all 2-4 hours away.

[James Powell]

There is at least one that I know of- Dave Bray in Toronto has one that is 4 3/4" gauge, he may come on here occasionally, but is not a regular like Don Carr or my dad.

So it is certainly possible to make one in 4 3/4". If you message my dad (or Don Carr) they likely have Dave's postal address- I don't know it off hand. A letter would probably get you a response on the difficulties. (I think Dave probably has computer & access, they might even have an email address for him).

James

[ironhorseriley]

Thanks, James. I may do that.

Jim