Errors on drawings

[alanstepney]

If anyone has details of any errors on any of the published drawings, please send me the details and I will add them to the appropriate page on my website.

That may help others from making mistakes, perhaps expensive ones, in the future.

www.alanstepney.info/page6.html

[dscott]

A good section on your web site, but with dwindling time in various workshops, people tend to keep errors to themselves and scrapped bits hidden deep in the scrap box!!!

I have a long list of Hunslet errors, but often these are the way the full size engine was machined or put together, verses the model as drawn out by the designer. These are on "Hunslet anyone" ? below.

The other is Boxhill which like most early ( what I call ME deadline designs ) are full of problems which continue as how can we alter an existing design and publish the results. The most annoying I remember was that I had the frame painted, all assembled running on air and the water tanks needed a 1/2" hole for the balancing pipes to go through them. Another was a push fit!!!! on the valve glands and being inside a pain to mend, yes it still needs mending.

And one on my SIMP design so far, which has been amended as the masters are in pencil on A3 small workshop friendly paper.

David.

[alanstepney]

people tend to keep errors to themselves

I have also had one person say that, "he had to find the mistakes, so why shouldnt everyone else".

I prefer to think that people are too busy on their own engine to commit errors to paper.

[Deleted]

Alan, I've encountered so called 'mentors' in engineering who have said exactly the same thing to apprentices!
Sad state of affairs which seems to be even worse today with people being protective about their jobs....
JB

[albert]

Hello Alan,
Ruston proctor 6ins. scale byLSM, Some dimensions still full size,Check every fraction dimension as one of the numbers may be wrong.
Bye Albert.

[6233]

Alan,

Just had a quick look at your site, looks very good. I will try to get 5 over the next week or so and put down the errors from my current projects, these being an LNWR 0-8-0 Wessie, theres lots on this loco, a Speedy which I am building more in line with the full sized loco so lots of mods and I have done some mods on my Duchess as she was built.

Regards

Mark

[dscott]

Dear Alan,

I managed to find 10 minutes to look at my Hunslet's last night, there being 2, the second even more modified as I went on with them. The most annoying bit being the slide bar brackets which were not deep enough to clear the coupling rods on there bottom stroke. These with 6 difficult to bolt up 2 BA's in place!!!
EACH.

My own conclusion is to do a re design from your own engine when you find and modify all the errors, and yes lets call it something else.

A1x Terrier or Stroudley's Little Wonder, would get us well past the copyright. As would Port Class Hunslet, or Slate Quarry Engine. or Victorian Dumper Truck!!

David.

With a growing pile of interesting scrap.

[Old Biker]

Alan - re: Martin Evans 5"G 2-4-0 Metro
If memory serves - and it has been a long time since the chassis was put on the shelf, if you make the buffer beams to the drawings, the outside frames foul the coupling rods by a good 1/8"
The answer is either to modify the buffer beams or (if you have already made them) put a joggle in the outside frames.
Mark

[alanstepney]

Thanks everyone for the information so far.

I'll make notes of it and add it to my website when next I update it.

[davidm]

Martin Evans's 5" Jinty.

No holes shown on frames for brake hanger brackets. (Though the bracket position is shown on the GA drawing).

Martin Evans's Simplex.

Firehole door will foul the right hand clack valve. This is easy to avoid; put a couple of feed bushes on the boiler barrel between the smokebox and the tanks.

David

[pauldenney]

Tich 3 1/2 "

Make the brake hangers 1/8th longer than stated otherwise the brake beams foul the frames. The forward break hangers are
very close to the cylinders, as the brakes don’t do much anyway might be best to leave the front ones off.

Tap the buffer beam when mounting the brake column, don’t try and use a nut underneath as it won’t fit.

More as they crop up.

Paul D

[standardsteam]

Seconded on the brake hangers. My reluctance to submit "errors" is that I can't be sure of my own work, for example, did I mis-read the drawing and make the hangers too short? I countersunk one of the front cover screws to give more clearance for the front hanger.

I found the reversing stand could do with being moved backwards, there isn't much room for the fingers in it's specified position when "notched up".

The oil tank bracket doesn't need the "set" in it if you have angle joints in your frames rather than "sifbronzing" the frames... There isn't a great deal of clearance between the combination lever(?) and the top of the slide bar if I recall in certain positions, I had to "releave" mine. Can't remember the rest.

Dec 12, 2008 12:21:29 GMT pauldenney said:

Tich 3 1/2 "

Make the brake hangers 1/8th longer than stated otherwise the brake beams foul the frames. The forward break hangers are
very close to the cylinders, as the brakes don’t do much anyway might be best to leave the front ones off.

Tap the buffer beam when mounting the brake column, don’t try and use a nut underneath as it won’t fit.

More as they crop up.

Paul D

[arch1947]

Hi Alan, I am building an LBSC designed Virginia in 3 1/2" and found a couple of problems.
1. The boiler won't fit if made to drawing. The friebox fouls the suspension either working or dummy. I raised the boiler 5/16" and narrowed the firebox and it just fits.

2.The boiler/firebox is too long making it very hard to fit the blowdown valve in the specified position.

3. The crank pins have no shoulder against which the coupling rods can run. This means that the rods would scuff the face of the drive wheels.

That is it so far,

Happy New Year,

Arch

[tbsteam]

3 1/2" Lickham/Lifford Hall

Smokebox is same diameter as the boiler (at the smokebox end ofcourse) when in un-cladded state so when cladded the boiler will be a wider diameter than the smokebox so the smokebox needs to be of a larger diameter, this is what i'm going to do :-

I'm going to make a ring that will be quite a tight fit over the tubeplate where it sticks out of the boiler to accept the current smokebox, this ring will be 3 13/16" OD and 3 11/16" ID (i think) and it only needs to be 1/4" or 1/2" thick, which with the smokebox (16G or 1/16") around it will give me 1/8" OD for cladding. The smokebox will need to be 3 7/8" OD instead of the current 3 3/4" and it will also need to be either 1/4" or 1/2" longer than specified (not got the drawings infront of me at the moment, but thats the only dimension i can't remember, will have a look at the drawings tomorrow an edit to suit).

If anybody requires the drawing i've done for it, just send me a PM or email!!

Cheers
tb

[tbsteam]

Forgot to mention :

Since there is only an injector and handpump on the Hall (ok, Hall 2 has got a crosshead pump, but i think i'm going to be taking this off), i am thinking of putting an axle pump on, but not where you'd expect it, i'm going to put it on the tender

Will put a new thread up if/when i do design it

Cheers
tb

[GWRdriver]

The ME Beam Engine (Reeves)
Disclaimer - I have not yet begun this engine and the items listed have been gleaned from various other builders and I have not yet their verified their accuracy or terminology.
1. The hole spacing for the steam chest bearing mounting holes and the holes in the base plate to not agree
2. The hole spacing for the Governor bracket mounting holes and the holes in the base plate to not agree
3. The distance from the entablature feet to the mounting hole is 3/32" short.
4. The entablature slots for mounting the radius rods are not in the correct location.
5. The connecting rod does not center on the beam, move crank arm face out 1/16" to allow the rod to center.
6. The crankshaft keyway needs to be longer to allow for the key for the governor bevel gear.
7. The entablature stay is 3/32" short on the 2-7/32" dimension
8. The base dimension (C to C?) of the main bearings should be 2", to match the base plate and pedestal bracket.
9. The valve crosshead needs .100" off the bottom around the center hole to give more clearance for the steam chest gland and the lock nut. The locknut only clears the top of the gland, with the gland all the way home, by about 1/64" and unless aligned just the right way or it fouled the gland bolts
10. The parallel motion assembly has an interference, there is not enough room for the links and pins to pass each other when the beam goes through its motion.
11. In the G.A. of the assembled engine a spacer pipe with a flange on both ends is shown between the steam pipe and the steam cock and throttle valve. There is no drawing for this and no length given.

The Stuart Beam Engine: (Built & verified)
1. The governor stand as-located (per old Dwg 90103) will result in the flyballs fouling the flywheel when in operation so the governor stand needs to be moved toward the cylinder end and the throttle rod adjusted accordingly.

Stuart D-10 - "New" drawings
1. Width dimension of crankshaft throws (over the outsides) is shown as 5/8" - should be 11/16".

[miner]

Harry, Thanks for the list of errors for the M.E. Beam. To use this as an example of my thoughts. While I don't know exactly when the drawings for this beam engine were first published, I do know it's been a long time. I can't believe that out of all the drawings and casting kits sold over the years for this engine that not one customer has mentioned this to Revees.

This hobby is almost completly about accuracy, Yet we still have company's making a profit from selling drawings and casting with known mistakes. I don't expect Revees to toss out there complete stock of these drawings and have new ones made, But a few penny's worth of paper and ink for a printed list of these mistakes, Included with all drawings/casting kits sold would be the proper thing to do. Then when the current supply of drawings are sold, Have the new ones printed with the mistakes removed. And a notation at the bottom of the drawing saying so.

As I live in Canada, A personal visit to Revees is not going to be done anytime soon, But it would be nice if someone on this board that makes regular visit's to them would print off Harry's list of mistakes, And then present this to Revees and ask them when they plan on fixing the problem. I'd say that this might be very interesting to anyone on this board that is a customer of Revees. If nothing is done, Then a letter to some of the Model Engineering magazines mentioning this would get their attention. I've used Revees as an example, But I think any other company selling Drawings/Castings with well known mistakes should be approached the same way.

Pete

[alanstepney]

I dont know of one model engineering drawing that is totally error-free.

Whilst it would be nice if drawings were perfect, the sellers, such as Reeves, only market drawings as supplied by the publisher, in this case, Model Engineer magazine.

To redraw all the designs that have been published over the years would be a monumental task, and one that is way beyond the resources of most companies, and nor would it be economic.

Although a wide generalisation, many of the more recent drawings are better than those from way back, and, in time, it is likely that all will be on Cad, be (mostly) error-free and errors can easily be corrected.
That is, until someone decides to build an "old" model!

To be practical, about the best that I can see is that we, the users, publish details of errors we have found, so that they can be helpful to future builders.

[diverjohn46]

I partly agree Alan. but it would not be outside the wit of man to actually include an addendum to drawings pointing out corrections/errors?

I've had a couple appear when I was building Springbok, the main one is that, if the frames and the boiler are built 'to drawings' then the blow down valve bushes and the holes for them in the frames don't actually line up.... This is I found out later is a well known problem! Also the running boards are too low and foul the top of the valve gear.

On Don Young's Doncaster, I have found that the front tender wheelsets foul the back of the front stretcher. I though it was my work, but having re drawn it and overlayed the wheels and axle centres I found that the 'interface' was designed in!

Now a minor problem like this I have no real problem with, though knowing in advance would be handy, but a situation where the boiler and frames won't match?

[fostergp6nhp]

Has anybody built 'Natal' as drawn by Martin Evans, if so what if any errors were there on the drawings?