Look at the boiler drawing – the hollow blower stay screws backwards into the blackhead and simultaneously forwards into the smokebox tubeplate. An interesting job to install!

Also while not an issue on a track with no points, but the spring pins foul pointwork if not shortnened.

It is well known in the Model Engineering world that many drawings from various different sources contain errors, and I know that this is much discussed at clubs and on forums such as this.

In the eight years that I have been running Kennions I have discovered that Model Engineers are some of the cleverest, intuitive and inventive people, and very often will solve a problem with drawings; the resulting satisfaction calming their initial frustration, and in no time at all they move on and the problem they had, the exact detail of it, and how they solved it becomes a distant memory only to be re discovered by the next person to come along.

May I just say, as a supplier to the industry, and I speak as someone who has never built a steam locomotive, how difficult it is to persuade customers to advise us in detail of any errors that they have found so that they can be corrected.

Of course we would not wish to sell drawings containing errors if we could correct them and we will endeavour to find someone to take a look at the Tich 7.1/4" for us.
Richard Clark

GLR Kennions Ltd

Peter,

I for one would really appreciate some clear pictures of your problems because I have considered building something like a large Tich some time in the future. It might also help Kennions and others builders.

Phil H

As a fan of old Model Engineer magazine, I can confirm readers have complained about errors in plans supplied with kits, articles, and books since Percival Marshall was a smooth cheeked lad. Finding errors seems to be part of the 'fun'.

Never likely to build anything as complicated as a Tich myself, but even for considerably simpler objects I like to more or less formally redraw plans to make sure I've understood them. Redrawing is a very good way of detecting mistakes and finding missing dimensions. Usually redrawing is no more than a back of an envelope sanity check, but I often go to the trouble of doing a working 2D drawing with projections in QCAD, or even build the object in 3D with FreeCAD. Fusion360 is my go to tool for checking dynamic aspects like joints, alignment, movement and interference, but I've also modelled moving parts in Meccano or Lolly Sticks and Cardboard.

I recommend Stewart Hart's Pottymill as a beginners first engine because the plans have no significant errors. My construction skills and ability to read plans improved enormously after building this relatively simple engine, and I now find it easier to eyeball mistooks in plans. I still check plans carefully though – it's a variant of 'measure twice, cut once'.

Dave

We now have someone willing to look at this with a view to us being able to issue revised drawings.

This may result in the need for adjustments to some of the castings and if necessary we will adjust the patterns to take account of this.

Richard Clark

GLR Kennions Ltd

at last as i struggled with my 5" Tich I have 2 complete sets of drawing both different at one point it was going in the scrap what i did in the end i got the important things working and I have a running chasse the rest will be best fit converted to metric as i feel fit. . I am 3/4 through building the boiler the only thing the drawing need notes on them rather ten getting eye strain looking at it for hours. I must say if a set of drawing was in a cad file in metric I would purchases a set.

Oh dear, the Golden Chestnut rears its ugly head AGAIN. Pity none of the old designers are no longer with us, they could be horsewhipped or lined up against a wall and machine gunned. That would ensure they never again made erroneous drawing/dimensional errors. Many items on the "Flee" ? the advertisers obviously don't have the ability/intelligence/determination to sort the problems or have swept them up from an estate sale and hope to be able to retire on the proceeds of an "Antique hand built" sale.

First, many of the drawings were originated BY HAND under the constraints of a limited timescale WITHOUT the advantages of CAD and 3D modelling facilities and the final customer being the checking facility.

In Industry, when DRAUGHTSMEN were employed to design and produce drawings for manufacture even the CHECKERS missed paper recorded errors and it wasn't until the design hit the shop floor that these were spotted and recorded. In the case of our "Toy" trains, errors cost the builder tens of pounds/dollars/yen. In industry, the quantity of the finished product determines the urgency of drawing mods on a COST basis, loss of a few thousand pounds, sort it out on the "Shop floor", mass production? sort drawings PDQ. This is not news to anyone who has actually worked in a DRAWING OFFICE and understands what is involved in the Mod system.

Todays suppliers are few and far between so trying to castigate one ( "Not Fit Foe Purpose&quot for a set of drawings probably not originated by themselves is a LITTLE offside. BCAD, the weapons of choice were a razor blade, pounce and a bottle of ink and the ability to understand the interaction of associated parts to changing ONE dimension. Many of todays designs are transposed, parrot fashion, by GRAPHICS persons who can produce a pretty picture but know naff all about how steam engines/locomotives work and despite the intricacies of electronic assistance, can still manage to miss record digits.

Never ceases to amuse those who chime "Is there a metric version"? With todays instant draughtsman program(me)s, it's the mere press of a button to instantly change for imperial to metric so what's the Problem? The problem is, the interaction of the various bits to each other in TRUE metrication of a design, an inch at 25.4mm has to be machined from something bigger if you say this is a metric "Conversion" rather than 25mm and UNDERSTANDING what difference (16 thou) makes to the design and the parts ASSOCIATED to it. So, IF YOU THINK YOU'RE BRAVE ENOUGH, HAVE A GO. Sadly, many were away from skool the day they did Maffs and an ability to count to more than twenty. Also, the inability for some keyboard warriors to locate the spline chunk button for English.

So PLEASE stop trying to shoot the messengers and as a modification to an old statement for those whose disposable income, so "What shall I do now?"far exceeds their ability, Six munce ago I cutn't even speel Muddle ingineer and now i are one.

Regards Ian

Long retired Drafty and Engineer.