Highland Bodgery

[uax6]

I'm trying to get a few of those unfinished projects out of the way, so the Banker has had a bit of work, rubbing down, patch painting to act as filler and then more rubbing down, and a coat of red oxide again.

After being sprayed this morning:

 

Hopefully it will dry soon and the finish be good enough to apply the top coat. There is some really crappy bits around the lifting rings on the tank tops, which I just can't clean up, so they will have to do. I think some fire irons on top will hide it.

 

I've been buying bits and bobs from ebay too, the latest batch being T9 tender bits. No expense spared here, as long as its around the £5 mark! I got 4 6 wheeled bodys for £4, and have been getting odd underframe bits as and when they appear. The T9 tenders are very useful for HR locos, as both the 6 and 8 wheeled ones are very close to HR ones. I'll be doing some stuff on these at some point in the future, and as always piccys and descriptions will be on here.

 

Do you remember way back I tried making a mould of a Banker chimney? Well this is how it turned out:

Not brillant, It would appear that the mould box needs to be a bit stronger than cardboard, so yesterday I decided to have another go, this time using plasticard (20thou):

The blue is plasticine, pushed down well, and then the chimney and sprues pushed in half way. I also decided to have a go at moulding a dome and safety valve bonnet (I might need them in the future). I decided that I could do these in a single mouldbox and as a single part mould (ie a flat bottom which you just pour into.). This meant that I needed to fill the bottom curve of the fittings so that they would sit flat with no undercuts. Plasticine was again used:

 

The two where then put into the mould box:

 

The next stage was to spray them with mould release (I used cheap Wilco house polish, as it has silicone in it. It doesn't say so on the tin, but if you spray it on your fingers you can feel the slippyness of it).

I then painted latex onto the fittings, and continued to pour it into the mould, tapping the sides to get the air bubbles to the top.

 

 

These have been left to dry, and hopefully they will be usable. If not I'll try again, and build up the moulds a small layer at a time.....

 

Andy

[ozzyo]

Another tip when applying numbers is to draw a thin pencil line (use one of the mechanical pencils for this, the lead is normal 0.5mm) about 1.5mm above and below all of the numbers on the sheet. So you then have two datums to work to. You could also draw in the C/Ls for the numbers as well. 

 

In one of your posts (#94) a while back you mentioned the spacing of the numbers, I think that you got some of them mixed up a bit.

a) Spacing between the centres of any two '1s' 13"

b ) Spacing between the centre of '1' and any other figure 15"

c) Spacing between the centres of any two other figures 19".

 

The above spacings are for 14" gold numerals (page 8 Locomotive liveries of the L.M.S.) 

 

The following are the spacings for the 18" gold numerals (page 5 of the above book),

a) Spacing between the centres of any two "1s" 16"

b ) Spacing between the centres of '1' and any other figure 20"

c) Spacing between the centres of any two other figures 24"

 

It also help when your fixing transfers to apply them onto a gloss background.

 

One other thing to watch out for if use numbers / letters from two different sheets is that the colour can be different on them, this can show up more on the gold coloured transfers, don't ask how I know?

 

Some nice building work going on here.

 

OzzyO.

 

EDIT. to add post number.

Edited July 4, 2013 by ozzyo

[Colin parks]

Hi Andy,

 

Just catching up with your thread.  You have been busy!  The Terrier looks nice and a lot chunkier than its southern cousin with the extended tanks and almost solid wheels.   The photos of your mould-making are interesting.  Can the moulds be re-used or are they one-offs? 

 

All the best,

 

Colin

[uax6]

I have got the measurements right on the loco, I think I just got confused writing them on here! I agree about both the colour and the gloss paint, and I don't intend to mix them again! Indeed I don't like the pressfix ones, and they are a real pain to get into the right place, the methsfix ones being all round better!

 

The Brighton Terriers look much older and more fragile than their older sisters, mind you I wonder if the Lochgorm ones would be able to match the work the Brighton ones did! I wounder if one of the A1X's could be cosmetically transformed into a Lochgorm one for a change?

 

The moulds I hope will be reusable. I will be using resin, if I can find the two bottles that I've had for 3 years in the garage, I hope it will be ok!

 

The bad news is that the Banker needs more filling.... and that J83 might get the razor saw attacking it too!

 

Andy

[N15class]

Another tip when applying numbers is to draw a thin pencil line (use one of the mechanical pencils for this, the lead is normal 0.5mm) about 1.5mm above and below all of the numbers on the sheet. So you then have two datums to work to. You could also draw in the C/Ls for the numbers as well. 

 

In one of your posts (#94) a while back you mentioned the spacing of the numbers, I think that you got some of them mixed up a bit.

a) Spacing between the centres of any two '1s' 13"

b ) Spacing between the centre of '1' and any other figure 15"

c) Spacing between the centres of any two other figures 19".

 

The above spacings are for 14" gold numerals (page 8 Locomotive liveries of the L.M.S.) 

 

The following are the spacings for the 18" gold numerals (page 5 of the above book),

a) Spacing between the centres of any two "1s" 16"

b ) Spacing between the centres of '1' and any other figure 20"

c) Spacing between the centres of any two other figures 24"

 

It also help when your fixing transfers to apply them onto a gloss background.

 

One other thing to watch out for if use numbers / letters from two different sheets is that the colour can be different on them, this can show up more on the gold coloured transfers, don't ask how I know?

 

Some nice building work going on here.

 

OzzyO.

 

EDIT. to add post number.

I do believe BR carried on the same spacings as LMS.

[Portchullin Tatty]

 I wounder if one of the A1X's could be cosmetically transformed into a Lochgorm one for a change?

 

 

Whilst I like the idea, I sense that this might be seen as heresy..............................

 

They could even use yoru thread as a guide!

[ozzyo]

I do believe BR carried on the same spacings as LMS.

 

Hello Peter,

 

I don't think that that can be correct, as the number sizes I mentioned were at the smallest were 14" .

 

When the "1947" livery was introduced, some things changed, in that before that centres of the letters L.M.S. were normal at 60" centres.

 

IIRC the centres of the letters on the Fowler tenders were at 53" with the M offset to the rear if the tender had a riveted body.

 

When the "1947" livery came in the centres were to be as follows 'M' to centre of 'L' 5'3" (or 63"), centre of 'M' to centre of 'S' 5'0" (or 60").

 

All numbers on the cab sides to be "total width for four figures to be 50". These numbers were to have been 12".  

 

May be the 50" dimension was keep to, I don't know?  

 

OzzyO.

[uax6]

Yesterday saw the razor saw coming out to play. The J83 needed some more surgery to get it to look like a Scrap Tank (it looks more like scrap at the minute mind!). Deciding where to cut was a challenge:

 

There was 2 mm to loose out of the bunker thus:

 

Then the main part of the cab was marked out and cut:

 

Anyone for a convertable tank?

 

The cab rear was then cleaned up and fettled to fit square with the remains of the bunker:

 

It was at this point that I realised that the cab was too tall. This isn't so much of an issue as the hieght adjustment has to come out of the bit above the cab windows. Cutting this might be difficult now it's glued back to the body, doh!

 

The rest of the cab will also need to be lowered, so that will make the cab even more of a jigsaw!

 

Andy

 

[uax6]

Strange day yesterday, a mix of no trains and then a service that limped back to normal. I should have been able to get on with things, but found that what I did took forever!

 

The needed to reduce the height of the cab, so took a saw to the rear, just above the rear spectacles:

I checked (before I cut) that the front spectacles where at the same height (which they were) and did the same to front of the cab:

 

Then it was working out how to cut the top section down so that it would lower the roof. I decided to keep the gutter, and then file up to about the top of the gutter across the back of the cut off section, and then to file the lower section so that the gutter would fit lower down on it. Sadly I forgot to take pictures before it was stuck to the cab again, but you can see the cuts in the following shots!

 

This shot gives you and impression on the height lost in the process, which would seem to make a huge difference:

 

Thats as far as I got, so today I hope to get the front of the cab done, and maybe the sides too!

 

Andy G

[Castle]

Hi Andy,

 

Some nice work going on here of some interesting prototypes - well done! When I used to make silicone moulds many moons ago, the trick to prevent bubbles was to get a very cheap or near ruined (as it will be ruined afterwards!) brush and very carefully paint a layer onto the surface of the object first. This means that even if the main pour has air in it, the critical surface doesn't. Possibly a bit late for this job you are doing but it may help yourself and others in future!

 

All the best,

 

Castle

[uax6]

I did brush the latex over the detail bits first, but I haven't yet had the courage to break them open yet!

 

I had a good day yesterday, even though the temperature in the box peaked at 29.6*C.

 

The first job was the sorting of the cab front, this shows what I forgot to take pictures of before:

 

The next shot shows how much height has been lost:

 

Then it was time to fill some holes. The front slotted spectacles were filled with roughly shaped bits of plasticard, along with the remaining holes in the boiler:

(the dome one was left to set one side before being bent over to the other)

 

Then it was on with the cab cutting. What a jigsaw! To remove the height I cut the bottom sheets off, stuck them in position and the filed the top to match. The pictures below say it easier than I can type it! The roof is short so a temporary bit of plasticard was cement in place to keep everything square. One thing I have done is cut off the plastic handrails, these were removed and filed back to the shape of the plastic curve, then a 0.45mm hole drilled in the end to take a wire.

 

 

A couple of things were noticed along the way, firstly the rear cab sheet wasn't square to the rear, so that was undone one side (using a knife to break the joint, after soaking in solvent) and a pair of calipers used to get it square. The rear of this joint has 10thou plasticard holding it now.

 

When I had finished and cemented the roof in place, I put it ontop of the drawing and noticed that the opening was still too large! This was because I hadn't noticed that the front curve to the handrails was longer on the J83 than I now need. This will need rectifying today, and this will also need the cab roof cutting to shorten the opening too. Oh the joys of bodging!

 

Andy

[Colin parks]

Hi Andy,

 

An epic bit of cutting there!

 

All the best,

 

Colin

[uax6]

Colin, it's not the cutting I fear, it's the sticking it all back together! Having said that it seems to be going ok at the minute (touching a lot of wood!) ;-}

 

Yesterday we left it at the stage where I had discoved that the cab handrails are two different distances away from the cab cut outs. To illustrate this point, here is one marked out to cut it back to the correct size:

 

The other side was done to match:

 

Then it was a case of cutting the roof to get the main opening the correct size (or at least closer to the correct size!):

 

Approx 2mm was removed from the roof, and then it was stuck back in position:

 

Then the handrail bits were glued back too:

 

The shape of the cabside is more or less there now, just need to fill the gaps with plasticard (not looking forward to doing the roof!) and then it will be cutting 5mm off the front of the tanks. That will need serious though about how I'm going to repair the boiler.....

 

Andy

[uax6]

Second update for today, I thought I'd chance a look at the moulds!

 

Here they are before breaking open:

 

So I started on the dome/safety valve one and peeled off the plasticard sides, after the first side had gone:

 

Second side, and all is looking well:

 

Third side reveals a huge air bubble:

 

Pulling the rubber from the box gives this:

 

The dome and bonnet are still in there, so a pair of pliers was used to grip the sprigot of the originals (through the plasticine), which gives this:

 

Difficult to see, but they look pretty good, no obvious air bubbles, so this mould looks like it might be useable!

 

Now the chimney one, with one side off:

 

One of the short sides off:

 

Pulled out of the plasticine:

 

Again looking good, I've just got to build up a mould box again to hold this side at the bottom, and to allow the other side to be poured. I think I'll have to put some plasticine around the edges of the rubber/box interface to stop the fresh stuff running down the sides and sticking it all together. Looking good!

 

Andy

 

[uax6]

The other day in work I made up another mould box to carry the first half of the chimney mould. Effectively I just rebuilt the original plasticard box around the rubber mould, with the addition of plasticine to fill any gaps:

 

This is awaiting spraying with mould release and then adding the rubber.

 

The J83 also got some work done, just closing up the gap in the cab with some 20thou plasticard, the bits around the gutter will need some shaping and additional material, but I think I might wait to do that after I have filled and sanded the sides smooth.

 

I think you will agree that it is begining to look like a cab again!

 

Still not really sure what to do with the tank front shortening, I think possibly the best way is to cut them down and then getting things back to the correct shape will probably be quite easy, certainly trying to picture it in my mind as it is, isn't!

 

Andy

[ChrisN]

The other day in work I made up another mould box to carry the first half of the chimney mould. Effectively I just rebuilt the original plasticard box around the rubber mould, with the addition of plasticine to fill any gaps:

DSC05620.JPG

DSC05621.JPG

 

This is awaiting spraying with mould release and then adding the rubber.

 

The J83 also got some work done, just closing up the gap in the cab with some 20thou plasticard, the bits around the gutter will need some shaping and additional material, but I think I might wait to do that after I have filled and sanded the sides smooth.

DSC05622.JPG

DSC05623.JPG

DSC05624.JPG

 

I think you will agree that it is begining to look like a cab again!

 

Still not really sure what to do with the tank front shortening, I think possibly the best way is to cut them down and then getting things back to the correct shape will probably be quite easy, certainly trying to picture it in my mind as it is, isn't!

 

Andy

 

Andy,

Keep up the good work.  As I have said before I will probably have to do something similar to build any Cambrian locomotives so it is both interesting and thought provoking.

[uax6]

Although I haven't put anything up on here I have been busy, and not just with DIY around the house!

 

I have done the first pour of resin into the moulds, I'm using Alumilite resin, which is quick and easy to use. I purchased some little waxed pill cups and some 5cc syringes from ebay so that I can measure out small amounts of the liquid resin (remembering not to mix the syringes in the wrong container!) and then put it into the waxed pot to mix. This all goes very quickly, and then I poured into the moulds, this is quite messy, and I'll probably use another syringe next time.

 

The castings take about 10mins to go hard, and again I sprayed my mould release into the moulds first. The results? Well have a look:

 

They are not perfect, but the overall shape is there. The chimney came out better than I expected, although it's not round, more oval! This means that I possible c*cked up the mould, so will have to have another go at that. (Any ideas from those that have done this sort of thing before?). The tool box came out well, except that it's base isn't level! Again I think the mould didn't work very well!

 

The chassis for the scrap tank has been altered so that it has the correct wheelbase, a case of drilling a 3mm hole in the right place, and then opening this out for the romford axle to rotate nicely. I gave a bit more top and bottom room, so there is a bit of flexibility in there. I still have pick-ups to sort out on one side (sadly the romfords are all insulated, unlike the ones that came off) but need to get some bronze strip for that job. And I need to fill the holes in the chassis from the original axle and the magnatraction magnet, some lead will be going in these!

 

I've now started to do the coupling rods, filing down the triang ones to the flute, and then shortening them down to fit. The first job took about 2 hours in work to do, and I'll endevour to solder them up this afternoon....

This picture shows the filed and unfiled rods:

 

The rods on the chassis:

 

And the bits to make up the front section:

 

Andy

 

 

[Castle]

Hi Andy,

 

What I would do to cast that is as a beginner is to not to try to do it as a 2 piece mould. What I used to do for a mould that i only needed a limited number of castings from was to just cast it in one solid block and then cut down with a scalpel in a sort of very slight zig - zag line to split it apart just enough to get the master out. The mould is definitely then going to go back together again in the right shape and the exactly the right place. I would also make the walls of the mould thicker to help it keep its shape. With much thicker walls, you can just use a bit of tape to hold the mould back together and pour in from the top. When pouring the mould making material you have to do it REALLY slowly otherwise your big air bubbles will ensue. Try wiggling a bit of wire round in the mould to dislodge any trapped air. Once you have poured it, why not put it on top of something that vibrates to get the air out? We used to use scroll saws or some other tool for 5 minutes in the absence of a vacuum chamber but in a domestic setting the washing machine will probably do... The final point is that I used to work with an RTV silicone casting medium which will make a FAR superior mould than what you are trying to use. Simple and reasonably cost effective kits are available on line (I have seen a few on eBay for example) which will make this process a whole lot easier for you.

 

I hope this helps!

 

All the best,

 

Castle

[uax6]

Castle,

 

I hadn't thought of just casting in one big block and then cutting one side to get the master out. It sounds like a much easier way of doing it, thanks.

 

As for the moulding medium, I fear you are probably correct in that RTV will probably be better, so later today I'll be off investigating this. I take it that RTV is more dimensionally stable? Does it require a mould release?

 

I've proved to myself that I can make moulds and cast from them, so now I just need to move up a gear!

 

Andy

[uax6]

We left the each coupling rod in two pieces, so yesterdays job was to make them one again. I found that the easiest way to do this was to file the back of the dummy joint and the front of the one ended piece thus:

 

Then using a convienate heat proof surface (this was a blue engineering brick I found outside!) I used plasticene to hold the rods in the correct position:

 

And then using a hot 25 watt iron, soldered them together:

 

Giving this end result:

 

Then with them fitted to the wheels:

 

After I had done the second rod I took the motor out and pushed the chassis back and forth to make sure nothing was binding. It took me a bit of time to realise that I had the cranks at 180* to each other, which did cause a bind! Then when I had sorted that out, I discovered that the triang crank pins (yes they are the same thread as the romford ones) were too long and were catching on the chassis block! All is now well!

 

Now for the first piston rod. These need a single bar crosshead, so using an old triang 2-6-2T one I opened the 'flaps' that used to sit over the rod guides so that they were flat, and then soldered a bit of box brass to it:

 

I discovered that you need to use a short length as getting the heat into the joint with a long length of box was impossible. Turning the assembly over I filed one flat off and made it a nice curve like the real thing (if a bit larger!) and filed the top down slightly to, giving this:

 

Then I ran out of time, but it's looking promising. Tomorrow I'm on 12hrs so should get the other cross head fixed and then I have to shorten the con rods...

 

Andy

[Castle]

Castle,

 

I hadn't thought of just casting in one big block and then cutting one side to get the master out. It sounds like a much easier way of doing it, thanks.

 

As for the moulding medium, I fear you are probably correct in that RTV will probably be better, so later today I'll be off investigating this. I take it that RTV is more dimensionally stable? Does it require a mould release?

 

I've proved to myself that I can make moulds and cast from them, so now I just need to move up a gear!

 

Andy

Hi Andy,

 

RTV silicone rubber doesn't usually need a release agent but it won't hurt to do so! I would check your type of release agent against the instructions on the silicone however, it has been some years since I last did this in anger... You are correct that it is very dimensionally stable. The only trick is to make sure that you mix it correctly. To this end when purchasing, get a little pot of silicone dye too and add this when adding the catalyst. This means that when the colour is even, the catalyst (which is water like in its consistency and clear) is mixed in too. One other tip is to just pour out from the mixing pot only - do NOT go scraping the edges and bottom of the pot. This is where if any of your rubber remains without catalyst will like to live and you don't want that in your mould! Use a cheap disposable paintbrush and paint it on first before main pour and pour very slowly (it does this weird, unnatural seeming folding thing if you are pouring it slowly enough - cool to look at!) and a quick vibrate on something (ooooh errrrr!) to get the air out and leave for 24hrs.

 

Make sure the walls are of a descent thickness and if you use superglue and accelerator to make the mould box, clean it and let it vent off for a little while as I very rarely had small issues with a local interaction between them and the RTV and away you go. Just cut as much as you need to get the master out and a bit of tape to hold the thing together as your pour your resin and away you go! I sometimes used to find that the first casting out of a new mould wasn't very good but subsequent ones were so if at first you don't succeed...

 

Have fun!

 

All the best,

 

Castle

[uax6]

Sorry for the lack of updates, i seem to be struggling getting to the computer at home (I can't load images here).

 

I have been working on the Scrap tank, but i seem to have got bogged down with the valve gear. The issue is that to clear the crankpin on the leading axle the cylinders need to be set quite far out, so much so that they look rediculous! I've spent the best part of two shifts trying to work out how to get round this, and to that end I have ordered some 12 and 14 BA nuts and bolts, hopefully I'll be able to sort it out when they arrive.

 

Question for Castle: How thick should i make the walls of the mould for the chimney? Would 10mm all round be enough, or should I go thicker?

 

Hopefully I'll get an update on here tomorrow morning.

 

Andy

[Castle]

Hi Andy,

 

Go to 15 - 20mm and it definitely won't give you any trouble. Also, it is quite tricky to mix up small quantities of silicone so err on a slightly larger mould. If you have more than one object to mould then do them all at once.

 

I hope this helps!

 

All the best,

 

Castle

[ozzyo]

What about using Lego to make the mould walls, with the bottom ones on some plasticard with plasticine to fix them in position. If you hang the parts in position from the runners you will also be able to use the Lego bricks to form the outside of the rubber mould when you pour what your going to cast the parts in. This should stop any misshaping of the rubber.

 

Let me know if you want me to do a drawing of what I mean. 

 

OzzyO.

 

PS. you can also make the walls to any size that you want and reuse the Lego bricks time and time again.

[uax6]

As promised a progress report:

 

The cylinders you will remember were made some time back when I was making a batch for the Castles, so I just had to drill for the piston rod and the slidebar. The slide bar is the smallest piece of square section brass rod that the model shop had (about 1.5mm). To get it to fit I had to file the end that fits inside the cylinder down. I also put a length of plastic tube down the middle for the piston rod to follow (as the scrap tanks cylinders had quite large glands on the front face of the cylinder:

 

 

This was when I got stumped with the joints. I'm still waiting for the bolts to turn up, so I'm guessing there won't be much progress there until they arrive. I think the cylinders will have to be a bit wider out than they should, but fingers crossed they won't look daft!

Heres a shot to show the issue:

 

So I moved on to other jobs. One of the most important is the height of the buffers. As Hornby locos are high and I've put bigger wheels on, which made it even higher, I had to lower the body 2mm. The front end was achieved by filing down the chassis:

 

The back was by a combination of chassis filing:

and slotting the body holes on the bunker:

I hope to be able to cover these over later.

 

To secure the body to the chassis I raided the previous jinty shell that had been on this chassis. It had had a brass angle araldited to the inside with a brass bolt and nut arrangement to secure it. This was filled down to fit, and mounted to a bit of plasticard inside the boiler:

(the plasticard was fixed to the boiler first and than the brass angle was screwed to the chassis and both offered up. When everything was in position superglue was injected.)

 

To cheer myself up I got some boiler fittings out to see what she will look like when finished:

 

I hope to get on with the front end today.......

 

Andy G