Scratch building (the way I do it)

[N15class]

I as part of my build for the 2015 build a loco competition I have been doing bits on my method of making the parts. I thought I would start a thread here. It may be of help or interest to those who may want to have a go themselves.

 

I will initially just transfer the post I have done there to here but I will add others as I go along.

 

Here is the copy of the first post.

 

 

 

As this is the first bit done since deciding to show my methods. It also happens to be the simplest bit of cutting and form, well I think it is anyway.

 

I am going to show you the routine for the cab roof of the G6. I use this method for most of the large pieces and when you need parts that are the same width, frame spacers etc. First off you need to find the roof size. Front to back is easy I measure the length of the cab and add 0.5mm overhang each end, some have more but this seems quite tight. For the length over the arc you can use geometry to get the answer, but with the model at hand I run a rule over the arc two or three times just to check it has not slipped, then add 1mm each side for over hang, this can be reduced with a file at the end if it is too much.

 

I am making this from 0.5mm (0.020") You can't cut right through so easily as you can with 0.25mm. Make sure the the edge of the sheet is straight and true up with a file if needed, I tend to use just one sheet for this sort of cutting so the edge is always straight. It is best to plan your cuts so you do not waste material. It may be better sometimes to cut out in a different method if the off cut will be of no use for other parts.

As you see here I use a 12" rule as the straight edge this one is so worn the numbers are invisible. I then use my best 6" one to set the cutting edge from the edge of the sheet, This is good down to about 0.25mm.

 

 

Next I score with a heavy duty knife, lightly at first and getting a little heavier once there the score line is deep enough not let the blade wander.

 

 

 

 

I then remove the straight edge and score vertically and quite firmly keeping digits out of the way. With 0.5mm sheet it is hard to go through but you will find the sheet starts bending upwards, look at the reverse and you should see where the knife has been. I find it easy now to snap the sheet. If the sheet wants to bend rather than the cut the cut is not deep enough score more. On narrow items it is best to use a smooth jaw vice to help when snapping.

 

 

 

Next check that there is a square end if not either cut it square as shown below or tidy up with a file if it is only a little out.  To cut the length off the strip requires I set an engineers square with the ruler as with the first cut.

After repeating the cutting process you can snap the part off. You will notice I have marked a double arrow on it. This saves rolling it the wrong way, I often mark before I do any cutting. I have made things the wrong way around and try to avoid if possible.

 

 

Next we need to form the curve on this. It is a simple arc. I have used my rollers, but it is just as easy with a broom handle etc on a mouse mat or Yellow pages. This is the same whether it is a roof like this or a boiler barrel. I used the hand method on all my 4mm builds.

 

 

 

Here we are resting on the cab with the right radius etc. It now just needs detailing which will take far longer than this.

 

 

 

I will add will be adding more shortly.

 

 

 

 

 

[Horsetan]

I do hope you explain your working inside motion!

[N15class]

I do hope you explain your working inside motion!

Good point. I will do that when I take it to bits for painting.

[Andy Reichert]

I've always had trouble with similar bending methods finding that the very ends of the sheet do not actually get curved. But yours look correct and great. Do you have something extra you do to achieve that, you can share?

 

Andy

[N15class]

I've always had trouble with similar bending methods finding that the very ends of the sheet do not actually get curved. But yours look correct and great. Do you have something extra you do to achieve that, you can share?

 

Andy

On a simple arc like the roof I just pass it through the rollers each way around a few times. But yes for boilers etc I tend to curve the ends slightly around a broom handle or similar. The easiest way is to lay a ruler on the bench and then put the sheet down onto the bench with the edge just on top of the steel rule then role the dowel over the sheet towards the rule, the last bit is curve the closer you go to the rule the tighter it will be. A very good of doing tumble  homes on coaches too.

I will show how in a future post as sometimes especially for me pictures are better than words.

[hayfield]

Peter

 

Thank you for starting a new thread, I for one will be very interested.

 

Before you start cutting anything what plans do you use please, as some plans only show certain profiles etc. Chassis frames is one example of things like wheels getting in the way

[N15class]

Peter

 

Thank you for starting a new thread, I for one will be very interested.

 

Before you start cutting anything what plans do you use please, as some plans only show certain profiles etc. Chassis frames is one example of things like wheels getting in the way

I like to get a general arrangement drawing if I can. But what ever drawing you use, you must cross check details to photos. The drawing is just a guide and things can be changed while being built or in the years of service since building. I create a file on here that has as many photos of the class I can find particularly the one I want to build if I can. This way you can see what has changed over the years, what the part actually looks like if you are not to good at picturing things off of a plan.

 

This is the GA that I am using for the G6 along with about 30 pictures I managed to find. I also have a couple of drawings that were done for modellers probably from magazines. But these again are just used as a secondary source if I cannot sort it out from the GA and photos.

 

 

Although you should not scale from drawings I always print a dozen copies scaled to full size for 7mm scale. I can the cut and paste onto the sheet material for cutting around. Mainly for things like the cab and tank sides, the frames. It is probably more accurate than trying to mark out all the dimensions needed.

[N15class]

Here is another part of my scratch building methods, (others are available) 

 

This time I am making out as the parts are not plain rectangles.

 

 I will be making the cab floor, the spacers to set the floor at the right height, two tool boxes to one each side of the coal hole, and the locker for the rear spectacle plate. Materials the floor is 0,5mm nickle silver. The tool boxes and locker are 0.25 brass as it was handy, and the spacers 0.5mm brass. The sizes are taken from drawings, scaled from pictures and sometimes guess work and the model. The cab floor needs to be made to fit what already has been done. But the height is taken from the drawings. The locker and tool boxes the depth and height are taken from the drawing but the width is looking at photos and guesstimating. You have thinks that give you hints like the spectacle windows the locker is not going to cover those, you may be able to see on a picture that it looks to be about half a windows space away from the window. Or if like me on this photos of the class are in short supply I have about 40, compared to the Ivatt tank where I have 200 ish not including the photos of the preserved engines. I looked at the O2 class very similar and guessed Adams would use a standard part rather raising a new drawing.

 

We as modellers do things wrong we take the GA drawing to build the model. The builders of the real thing would have a drawing for each component. The GA just shows them where that bit should fit. This is why we need to look at pictures so much. just to check the the builder actually put the part where the GA said and to see what other repairs modification have been made through its life up to the date you wish to model.

 

I know I will probably keep repeating these things but it is important if we want to get closer to an accurate model of the prototype. I know we have to have compromises, because we may be running on the wrong gauge, need to fit an electric motor. But if we are going down the scratch building modifying a kit route, it is either because we are unhappy with what was available or we enjoy actually building something. Me I want to stretch my ability with each new model, and learn something new with each build if I can. So if you can get a picture of both sides of the loco and in the era you are modelling. With my G6 I only have a few photos in the era and livery mine will be in so lots of educated guessing. If some one comes up with things I have got wrong all the better.

 

Right enough waffling time to do something.

 

First off as they are quite simple shapes I do very poor sketches on a scrap of paper, this just acts as an aid memoir, and saves keep having to remember. You will see I have written small next to a couple of numbers. This is just a reference to know I need to make slightly smaller. Take the width I know the spectacles etc are all 55mm. So if I make the floor 55mm wide it will be a struggle to get it in. So a few extra passes with the file you will have something that will go in easier ideal if it needs to be removed a few times before permanently fitting or you want it as a removable item.

 

 

 

 

Next up is solder any multiple layers as needed. Here I have folded the end of a piece of material for the tool boxes, the locker will be cut from the rest of the piece. The floor spacers four pieces have been soldered together. I always have a pile of off cuts on the bench from previous parts I will check these first before soldering more together, saves material and time. Also I quite often use large pieces as it is less wasteful and easier to hold.

 

 

Next  we need to mark out for this I coat the surface with either black or blue indelible marker. Then it is a combination of ruler square, dividers and scriber. Again as before I make sure that one edge is straight, this then works as the datum for measuring and to square of off. the first picture shows the first line drawn. This was measured from the straight edge, I put the handle of the square against the edge and hold the ruler against this. It is the easiest way I know to get the ruler in line with the edge. I then mar the dimension with the scriber. I do this both sides of the sheet. Get them as far apart as possible as you end up with less error when the line is drawn.

 

 

You can use dividers with one pin extended slightly, or odd leg calipers. ( which I always mean to buy) Aswell for scribing these lines that are parallel to the datum edge.

 

I then draw a centre line using the square, I then prefer to use the dividers for marking out either side of it I just scribe a little arc with them at the set dimension, then locate the scriber point on the arc, you can often feel the tip going into the arc just scribed. Then slide the square to the scriber. I find this way around is more accurate for me.

 

 

 

Here are the the floor, boxes, and locker all marked out.

 

 

This is my set up for using the piercing saw.

 

 

 

 

Now hopefully the video I made whilst cutting out the floor will be of interest. I use 3 blade sizes for the saw. O, 4 O and 6 O.

 

 

To be continued, I will show how the parts are folded etc next post.

Edited June 22, 2015 by N15class

[N15class]

Following on from the previous episode.

 

Here are the parts after cutting out but prior to filing. Followed but the parts having been separated and still needing the solder cleaning up.From left to right,floor spacers, bunker tool boxes and lids, locker and the cab floor.

 

 

 

I now need to to fold up the locker and tool boxes. I find to get a nice sharp corner you need to do a little work. It is either this or soldering lots of bits together to make the boxes, Not nice when the components are small. Firstly I score the fold line a few times as if you were wanting to cut through. I do this as the shallow grove is a guide for the three square or square file. Working with one corner in the grove lightly at first, or you may not follow it, one there is a reasonable groove you can press harder. When you can see the tell tail line in the other side you have gone deep enough. It will now fold just like a half etched corner in a kit. It does not look as neat as it should. I was rushing as I wanted to get the photos etc before collecting my wife.

 

 

 

Depending on the size of the components I will either use smooth jaw pliers, my vice which also has smooth jaws which are 59mm wide, or 250mm bending bars. I will do these fold in the vice apart the bottom of the locker which was done with the pliers. I set the part up with the fold just above the top of the jaws this allows a slight space for bending it to just over 90 degrees it will spring back a little. If you try folding with the jaws in line with the centre of the grove you will never get it to 90 degrees.

 

 

And the tool boxes with the lids soldered on.

 

 

 

Here the floor is in place but the locker etc are just tacked until I take the back out and add the details of hinges etc, please do not look at the soldering I had already unplugged and did not get away with it. The rear spectacle plate will be removed and the boxes will be soldered whilst it is out. The other detail will be added to them at the same time. Also as the floor is in I can now add the sides and ends of the side tanks inside the cab.

 

 

 

 

The G6 is going into the cupboard for a few days as I need to get an Ivatt 2MT tank.

[sleeper]

Hi Pete,

Did you make your rollers for forming boilers etc or are they ready made? if you get time maybe you could do a short demo of them

 

cheers Roly

[N15class]

Hi Pete,

Did you make your rollers for forming boilers etc or are they ready made? if you get time maybe you could do a short demo of them

 

cheers Roly

Hi

 

No I bought them from GW models. I had the 6" ones originally. But I traded them for 10". I wish to some extent I had kept the shorter ones. There is not too much in 7mm that is ove 6" long. The ones I have now flex a little in the middle. So you have to be very careful with larger items.

Yes I will do a video to show there use.

[DavidB]

I'm loving this thread Peter - it's so refreshing to see this kind of work being done amidst all of the petty grumbling elsewhere about the perceived shortcomings of mass produced models and their manufacturers. Some useful tips too for my own current and planned scratch builds. More please!

 

David

[N15class]

Sorting out the details for the Ivatt I came to fit the boiler washout plugs, only to find there were non or I had lost them, most likely the previous.

 

The boiler ones are recessed in from the cladding. So after a little thought I decided to use a length of tube with a scrap of brass at one end with a central hole with a length square bar.

 

I decided to do one to check it all worked, but as soon as I started I decided to use telescoping tube. 4mm, 3mm, and 2mm along with 1mm square bar for the plug.

 

I started off by measuring and cutting the tube I ct the 4mm to 3mm in length. I then realised the length is not critical as when together they can be adjust to the right depth. Again for cutting I use a heavy duty knife, by rolling the tube under the blade it works like a pipe cutter. The newer the blade the less burr you need to clean out from the internal hole. Watch they don't ping away or you will make more than needed.

 

 

I then soldered the rings of the 3mm tube over the 2mm, which will be cut later. File the end flat.

 

 

I then put a length of 1mm square in a pin vice with about 1.5mm sticking out. The four corners were than given a very gentle wipe with a needle file. This is because 1mm square does not fit in a 1mm round hole. Be gentle or you will over do it. I then push it into the hole and solder in place. Cut and file to length, I left them about 0.75mm long. I used a 500mm length of square, by soldering then cutting there is no waste and no trying to get 4 bits the same.

 

 

Now slip what you already have done into the 4mm tube rings and I used the depth gauge on my vernier to set the top of the plug 0.75 from the top. Solder the outer ring in place. It is now time to cut the 2mm tube do this as close as you can to the 3mm. Again no waste, in fact all the material you have cut has been use.

 

 

Here are three all completed ready to go in. The forth is already in place. It was made to prove the theory. You will see from the side view they are all different, but from the business end they are the same.

 

 

Here they are soldered in place, I am pleased this. It is one of the jobs that gets put off, because it seems more complicated than it is in reality.

 

 

It slowed the build slightly but it only a hour or so and adds to the overall effect.  I hope I have showed that there are simple ways to do things, and it can be with just a few tools. Yes it can use more tools and a lathe, but I am sure the result would be no better. I always try and work to the KISS principle of engineering.

 

 

 

 

[N15class]

I'm loving this thread Peter - it's so refreshing to see this kind of work being done amidst all of the petty grumbling elsewhere about the perceived shortcomings of mass produced models and their manufacturers. Some useful tips too for my own current and planned scratch builds. More please!

 

David

Thanks

I have always preferred doing rather than waiting for someone else. When I was working I used to be climbing the walls at the end of the day whist training the apprentice carpenters. Watching them spend the day doing 3 hours work, it was so hard not to grab their tools and do the job.

 

If you are on about the latest Hornby model I think I may of instigated something by stating something about the handrail.

Edited June 24, 2015 by N15class

[Horsetan]

....climbing the was ....

 

Climbing the what? *scratches head*

[Stubby47]

Climbing the what? *scratches head*

 

 walls ?

[ianblenk]

This is brilliant! Ever thought about writing a book?

 

Ian B.

[ian@stenochs]

I like the washout plugs. A shortcut I have used is to utilise 4mm axle bearings, the type for pinpoint bearings. Just drill a hole to suit the square wire. I had lots left from my P4 days when I started again in S7 but they are quite cheap to buy.

Ian.

[micknich2003]

I too am enjoying this thread. If you can get hold of them, read the Model Railroader articles on loco building wrote by the late Mel Thornburgh from the mid '30's to the early '60's. Mel was a genius and using only the most basic hand tools he turned a sheet of tinplate into a museum quality model.

[N15class]

Climbing the what? *scratches head*

My fingers never type as quickly as I think, Now corrected. Must proof read.

[N15class]

This is brilliant! Ever thought about writing a book?

 

Ian B.

Thanks Ian

It has never crossed my mind. After reading Guy Williams book, I thought my efforts were quite poor.

 

I like the washout plugs. A shortcut I have used is to utilise 4mm axle bearings, the type for pinpoint bearings. Just drill a hole to suit the square wire. I had lots left from my P4 days when I started again in S7 but they are quite cheap to buy.

Ian.

Thanks Ian

 

Now that's a good idea. I will need some more fire box plugs soon.

 

I too am enjoying this thread. If you can get hold of them, read the Model Railroader articles on loco building wrote by the late Mel Thornburgh from the mid '30's to the early '60's. Mel was a genius and using only the most basic hand tools he turned a sheet of tinplate into a museum quality model.

Thanks Mick

 

I had not known about Mel but will look him up and add to my reading list.

[Jon Fitness]

Thanks

I have always preferred doing rather than waiting for someone else. When I was working I used to be climbing the walls at the end of the day whist training the apprentice carpenters. Watching them spend the day doing 3 hours work, it was so hard not to grab their tools and do the job.

 

If you are on about the latest Hornby model I think I may of instigated something by stating something about the handrail.

I suppose it's important to be able to improvise and make your own bits rather than wait for the rather dodgy postal service that appears to hinder your progress!

JF

[N15class]

I suppose it's important to be able to improvise and make your own bits rather than wait for the rather dodgy postal service that appears to hinder your progress!

JF

I think it was more the years of being a skint single parent, who liked expensive toys.

[hayfield]

Peter

 

We each take inspiration from those who have the ability to communicate on a level we can understand, especially when the methods used are within our own capabilities.

 

I have never yet been able/ attempted to scratch build a loco in metal and is something after following your threads I plan to do. Cost of the project is an important reason, but for the modellers of us obtain much pleasure when building something from a kit and are rightly proud of our efforts. Being able to scratch build must be very satisfying indeed.

 

Please keep your building methods coming. I for one would like to know what information you need prior to starting a project (idiots guide please) Thanks for showing the GA drawing but do you use other things as well

Edited June 25, 2015 by hayfield

[ianblenk]

Hi Peter,

 

Write the book!

 

I have been inspired to try and complete a Neilson box tank I started some years ago, you make everything accessible.

 

Ian B