Super Simplex – Motion Plates from Model Engineers Laser

[David WassonParticipant @davidwasson11489]

For folks building a Super Simplex, I just wanted to give you a heads up if you are going to use the motion plate from Model Engineers Laser. The "window" in the motion plate that the cross head guide bars fit into, is positioned 1/16" too high. Also, the dimension from the top of the plate to the center of the window is not correct as shown in the ME article. It should be 2-5/8" as shown on a current version of the drawing. The plate can be used, if positioned 1/16" below the top edge of the frame.

Of course, the plate will no longer support the running board but, a 1/16" spacer can be put under the running board in this area.

Also, there is a radius that was added to the edge of the window that is not shown in any version of the motion plate drawings. This radius will foul the connecting rod when the leading wheels move all the way to the left or right.

The wheels in the photo have been moved all the way to the left. The circled area shows the radius on the motion plate touching the con rod.

This can be put right by machining the inside of the window straight down, as shown on the drawings.

Hope this helps out a few folks attempting this build. In general, the laser cut parts are a real time saver and I would recommend them for anyone building a locomotive. Just make sure the parts match the drawing, and that the drawing is correct!

David

p.s. For Julian, I have reduced the inside diameter of the cylinders. John Baguley has a wonderful web site including some downloadable spread sheets to help design locomotives. Yes, the cylinders are a bit large for the boiler. I have reduced them to 1-3/8" inside diameter. This is more in proportion to the grate and boiler size.

[David WassonParticipant @davidwasson11489]

[Neil WyattModerator @neilwyatt]

Have you let Malcolm know about this error?

I am sure he will correct it promptly.

Neil

[David WassonParticipant @davidwasson11489]

Hi Neil,

Yes, I have let Malcolm know about this several weeks ago. In fact I asked for corrected or replacement parts. He asked for the correct drawings, which I gladly supplied him with. His response was "not sure it was a long time ago".

So, I guess he acknowledges the errors and will hopefully make corrections. It is not clear what he is going to do for future parts, he would not say. I know this is a hobby business for him and may not have much time to make corrections. He saw that I moved on with the incorrect parts that I have and am able to make them work in spite of the errors. Perhaps that is why he did not offer to correct or replace the incorrect parts even though I asked in my first email to him.

As I have moved on in my build, replacement or corrected parts are really no longer important.

I encouraged him to pass on my "fix" to future customers if he is going to continue selling the same uncorrected parts.

David

[John KinnaneParticipant @johnkinnane64270]

G'day David thank you for mentioning that with laser cut frames. I am a novice a this and I am buying the frames and spaces lazer cut. It was also interesting in relation to reducing the size of the cylinder boars which I did wonder about when I saw the size of them. There questions and problems that will come up, would it be alright to ask you and the other members for some help and guidance. Once again thank you regards John Kinnane Tasmania Australia

[David WassonParticipant @davidwasson11489]

Hi John.

Yes, in general, the laser cut parts are a real time saver. Understand, that the thickness of the parts are made to the closest metric size as for thickness, Mostly this is not a problem if you are aware of it. The only parts that I machined to correct thickness are the outside plates for the expansion link. As received from Malcolm, the parts are really a bit too thick to deal without making other changes, specifically, the positions of the expansion link brackets.

As for the cylinder bores, there is an important relation of grate size to quantity of steam that a boiler can generate. The locomotive will probably work just fine as designed, but, it is possible that on a long run, you may use steam a little bit faster than the boiler can generate it. Reducing the cylinder bore will reduce the steam demand. At 1-3/8" bore, there is still plenty of power to spin the wheels.

Yes, if you have any questions, you can send them my way. I am no expert at locomotive building and am learning, and having fun as I go!  

Here's a photo of my progress as of a few days ago:

David

 

Edited By David Wasson on 23/12/2015 01:07:16

[John KinnaneParticipant @johnkinnane64270]

Hi David thank you very much for your reply and words of advice and from all members. The photos look terrific and I can only hope my comes out like yours. Will talk soon John

[Stewart HartParticipant @stewarthart90345]

Posted by David Wasson on 23/12/2015 01:03:13:

As for the cylinder bores, there is an important relation of grate size to quantity of steam that a boiler can generate. The locomotive will probably work just fine as designed, but, it is possible that on a long run, you may use steam a little bit faster than the boiler can generate it. Reducing the cylinder bore will reduce the steam demand. At 1-3/8" bore, there is still plenty of power to spin the wheels.

David

Edited By David Wasson on 23/12/2015 01:07:16

Just to add a bit of actual running information,

I have a Simplex but its fitted with a flat top belpher boiler grate size is corect to Simplex spec and the cylinders are 1 1/2". At our clubs just for fun efficiency competition last summer I ran it without stopping for 30 min pulling two trucks loaded with four adults in total, completed 3.2 miles at a average speed 6.4 mph without showing any sign of running out of steam,

At that performance I'd ? the need to reduce the size of the cylinders, unless the belpher boiler is a better producer of steam.

Stew

[David WassonParticipant @davidwasson11489]

Hi Stew,

Thanks for some real life experience. This is always helpful. Sounds like your Simplex is a real work horse and is really getting the job done. As for the boiler, do you mean a Belpaire boiler? I wonder what difference the boiler has made? Martin Evans has noted that the Belpaire boiler gives greater water volume over the top of the fire box and thus is a more efficient steam raiser. What was the reason for making a Belpaire boiler? It is quite a bit more trouble to build that type.

My boiler will be as per the drawing. Also, the grate will be 1/4" narrower than originally designed, as I am re-gauging the locomotive to 4-3/4". It will be interesting to see how this all woks out.

David

[Stewart HartParticipant @stewarthart90345]

Hi David

I bought the loco part finished and it came with the Belpaire boiler I had to extensively re-work a lot of the parts, as they had been made with more enthusiasm than skill but the boiler seems to have been well made. At my club there are quite a few Simplex loco running, six at the last count two of them have Belpair boilers including mine, but to be honest its difficult to quantify the difference. There was one other round top boiler Simplex took part last summer, but unfortunately it had to withdraw due to a mechanical problem, so we couldn't compare performance next year maybe.

Why the change in gauge ?.

Stew

[Another JohnSParticipant @anotherjohns]

Posted by Stewart Hart on 23/12/2015 11:08:18:

Why the change in gauge ?.

Stew – if I may step in here – most of North America uses 4-3/4 instead of 5" gauge. (same problem with 7-1/4 and 7-1/2" &nbsp

Some clubs do have 5" gauge – I can think of a couple – but 4-3/4" rules the roost. My local club uses 5" gauge, which means the locomotives are basically stuck running on this track, and one other. (I know of one other "local" track that had 5 and 7-1/4" on the ground, but I think that the 5" is not servicable any more, as 7-1/4 is used for hauling the public)

It's one of the reasons why I like to push 3-1/2" gauge – it is a world standard!

John.

Edited By John Alexander Stewart on 23/12/2015 12:54:45

[Stewart HartParticipant @stewarthart90345]

Hi John

Thanks for the explanation:- I thought the battle of the gauges had been settled, evidently not, we don't seem to have the same mix of gauges her in the UK.

Cheers

Stew

[David WassonParticipant @davidwasson11489]

Hi Stew,

Thanks for the explanation of how your boiler was constructed. It would be interesting to see if the Belpaire performs differently from the round top boilers.

As for the change in gauge, John is correct. Mostly in North America, 1" scale runs on 4-3/4" gauge track. In fact, there are several 4-3/4" gauge tracks within a few hours travel from my place. I don't know of any 5" tracks in my part of the country.

Along with many other reasons, the Simplex looked like a locomotive that could easily be squeezed to fit 4-3/4" track. So far this has not been a problem during my build. I am not changing any of the lengthwise dimensions, only the distance between the frames. This also allows everything above the frames to remain as drawn. The saddle will require a little modification and of course, the fire box gets squeezed as it just fits between the frames.

David

[John KinnaneParticipant @johnkinnane64270]

Hi everyone just a question on looking at the drawings for the super simplex, I notice that drill hole-for spaces ect., are numbered such as ba9 or ba 27 does this refer to bolt or size? Or taping size. Also would be a good set of taps with plugs and dies in imperial that would be good to use to build this loco, buying on them on eBay is the best as I live in Tasmania. Thank you regards John. PS any advice on same would be much appreciated

[David WassonParticipant @davidwasson11489]

Hi John,

BA, as found on the Super Simplex drawings, is in reference to British Association threads. These are special fine pitch threads. I do not believe there is a BA27 as you have mentioned. In any case, it is possible to substitute metric or imperial threads for most of the BA threads. All the fasteners you see in my posts are standard U.S. threaded fasteners. Diameters for BA threads are easily found on the net so you can make logical substitutions with fasteners that would be more available for you. Using what you have is usually not an issue, just make sure you pay attention to the diameter.

David

[John KinnaneParticipant @johnkinnane64270]

G'day David thank you very much for your reply, it straightened out a few issue I was having particularly if I dicided to go down the metric road, as I all ready have metric taps and dies. Thank you once again John

[John KinnaneParticipant @johnkinnane64270]

G'day everyone I received my lazer cut frames today for the super simplex loco. When I placed them on the drawings they are about 3mm short on the front also the 2nd cut away for the axel box doesn't line up with what is on the drawing.

Is the simplex loco smaller than the super simplex and if so they are the wrong ones, I would really appreciate any help in this regard, also is it that you don't follow the drawings to the letter. Tassie John

[David WassonParticipant @davidwasson11489]

Hi John,

The frames for the the Super and the "regular" Simplex are not the same. Also, when checking dimensions, you need to use the numbers as printed on the drawings. The drawings themselves are not always drawn correctly to scale, but, the actual dimensions are usually correct. Laying a part on the drawing is not always the best way to check for dimensional errors. Make sure you measure the part against the dimensions on the drawing.

David

[John KinnaneParticipant @johnkinnane64270]

Thank you very much David I will check them out tomorrow and let you know. As a new cummer to model engineering I really appreciate the feed back that I get from the questions I ask. Regards John

[John KinnaneParticipant @johnkinnane64270]

G'day David I went and measured them as I couldn't wait for the morning and you were absolutely right the drawings are not to scale, I did what you suggested and they are correct size (super simplex). I have learned a valuable lesson to always measure off the drawings. Thank you once again John Kinnane Tasmania Australia

[David WassonParticipant @davidwasson11489]

Hi John,

Well, that's good to know! The frames are pretty important that the dimensions are correct.

The frames are one part that I did not make from laser cut parts. I could not wait to get started, so I made them all myself as per the drawing.

Glad to be of help!

David

[John KinnaneParticipant @johnkinnane64270]

Hi everyone I have the frames and I have been studying the drawings, also reading about building the super simplex. I am at the stage of setting up the stretchers to the frames, I don't understand on the Drawings it denotes using a No 34 hole, which I think is a imperial drill size and then use 6BA bolts and tape into the stretcher. I understand that they are small type bolts so they do not interfere with the back of the wheels. I would appreciate any help thank you John Super Simplex

[Stewart HartParticipant @stewarthart90345]

Hi John

No 34 is a number drill size its an old imperial system you have No drill 1 to 60:- 1 being the largest 60 the smallest above 1 you go to letter sizes, the system is mathematical based I think its a geometric progression I'm sure some smart Alex will correct me if I'm wrong, just do a google search for number drills and all will be clear. Its is a good system though and still in widely used.

For my Simplex I used M3 countersunk socket screws from her http://www.modelfixings.co.uk/ht_metric_countersunks.htm to fasten the frame and stretchers together

Just drill the hole in the frame 3.2mm and buy yourself a good countersinking to countersink them, make sure you countersink the correct side of the frame though.

Stew

[John KinnaneParticipant @johnkinnane64270]

Thank you very much Stew that helped a lot, do you know of a chart or book that has numbers of the drill bit to what drill bit to the tap you use much appreciated any information especially if you can buy on eBay ect and imperial, sort of like a machinist book but easy to understand thank you John Kinnane Tasmania Australia

[Stewart HartParticipant @stewarthart90345]

This is the sort of thing you want

You can get metric or imperial also just do a googlle search there are plenty of on line tables and chart to down load you just have to look.

zeuss book on ebay

http://www.ebay.co.uk/sch/i.html?poi=&adpos=1t3&ul_noapp=true&geo_id=32251&MT_ID=10&crlp=87837111630_847&keyword=engineers+zeus+book&rlsatarget=kwd-92888814320&_nkw=engineers+zeus+book&device=c&crdt=0&treatment_id=7&clk_rvr_id=967353598704

Stew

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