eddieprice

I want to build a 32 bit to 5 bit encoder using a diode matrix. I am happy with the circuit for the diode matrix - there are 32 rows with 5 columns with diodes placed at the appropriate intersections to generate a 5 bit BCD code. The code for each of the 32 rows is obtained by closing a switch to +5V. My question relates to a need to note which switches have been operated to set-up the required route for the turnouts and feeds for a z gauge model railway. I would like to place an LED against each switch which would illuminate and stay illuminated as each switch is operated - the switch is operated once and then returned to its OFF position. I need some sort of latch. I thought of a D-type such as the SN74HC373 octal latch. I have tried various connections but cannot achieve the effect that I want. Is a D-type the right sort of thing or is there something else? Eddie Price

Just been reading some of the threads on 3D printing, and it has got me thinking that it could be a way of making the roof. There is a lot of detail on the class 47 roof which would be difficult to scratch build. But it would be nice to get hold of some decent drawings. Does anyone know of a source for the class47. Up to now I have been using photographs.

Making progress slowly. I now have a chassis and cab framework. There is a 6V lead acid battery in the middle. I think 6V should be enough; it would be a simple matter to change it for a 12V battery. From the motor spec. I will need about 4.8V to achieve a scale maximum speed of 80mph. I need now to complete the radio control circuitry to see if it runs.

Thought you might like to see what progress I am making with my Gauge 1 model of a Class 47. To date I am part way through making the two bogies. The side frames are machined from 6mm brass. There are two electric motors to each bogie. I am in the process of making the brake lever details for each bogie - there are a lot of bits!!!

Thanks Tom. Just what I need. Nice photo as well. Good view of the buffers. Eddie

Hi again. Can anyone tell me what the dimensions of the buffer beam are in the Class47. This is a front view, but it is difficult to judge what happens behind the buffers. I believe the buffers are 22" in diameter. It looks as though it should be about 7' 6" wide.

Yes I think you are right. Only the front box is attached by means of a pivot. For the central box the beam enters a box like structure beneath the axle box as can be seen in this photo that I found on Flikr. This is a photo of a couple of guys painting a class47 and it does show the beam entering into an opening beneath the axle box.

Thanks Pugsley. Yes I can see what you mean. I found this drawing today and as you say my "suspension" beam is an equalising beam. The two outer axle boxes appear to be attached by a pivot to the equalising beam. What about the centre box? Is the beam attached in a similar manner to the centre axle box or is it attached to the frame?

I am still looking for class47 detailed shots to help with building a gauge 1 version. I am trying to puzzle out what keeps the axle boxes in place. Here is an image. I know there is a suspension bar beneath the axle box. Is this what holds the box in place? The box can move up and down. Is there anything to prevent the box moving in and out, apart from the suspension bar fitting in a slot at the bottom of the box? I have built a couple of steam locos and the sides of the axle boxes are slotted so that they can only move up and down in the horns.

I think I have worked out how the inner set of springs are attached to the bogie and the spider, and so on with the machining.

Hello Jon. I wonder if I could beg some information about your model. I am interested in the springs on the bogie. I can understand the outer pair, but am not clear of where the bottom ends of the second inner pair attach. I assume the tops are attached to, what I think is called the spider. You can see it in one of my photos above. It houses the bearing that connects the bogie to the body work. It looks as though the bottom end may be attached to, what I call, the supension arms that are connected to the axle boxes??? I have started to machine brass for the bogie. I have machined the wheels - all one dozen!!! Eddie Price

Jon, have you tried www.class47.co.uk. There are some photos there of the 47414, but not detailed ones. Google "class47 47414"

Beautiful modelling Jon. Gives me something to aim for. As to the spring Tom, I would say it's 5" in diameter by 20" long, based on a photograph published by you actually last July. I imported the photo into my CAD program. I then added a circle to match the wheel, which should be 3' 9" in diameter. From this I scaled the spring.

Been playing around with Google Sketchup and this is an image of the bogie that I hope to make. Its a 2D image rather than the 3D one produced within Sketchup. But the 3D file is about 5Mb and you need a viewer to see it

Some great photographs. I have made a start on making the bogies and there is a lot of detail in some of your photos. Also a good side elevation of the complete loco. Most photos are taken 3/4 view and are impossible to scale. Great Eddie Price