iploffy
OC Blue Brigade
Yess... err... When will anyone ask about the colour that shall not be mentioned?
regards, Graham
not saying anything causes toooooo much trouble
7mm Steph's Infernal Combustion Workbench
- Thread starter Steph Dale
- Start date
not saying anything causes toooooo much trouble
Eastsidepilot
Western Thunderer
Steph Dale
Western Thunderer
And we're off...
This afternoon I started the model much as I usually do - by making sure many of the components are ready for assembly. In this case the obvious place to start was with the wheels, other jobs being done to fit around the effort and glue-setting times.
Here's the wheel showing how the original wheel (on the right) is hacked about and the front disc dropped in (left). The shape of the spokes really helps up by providing nice flat lands on which the disc can seat. Please note that this is the 'proof of concept' made up - the 'production' centres are in nickel-silver:
So after hacking all the wheel centres about they were then keyed using a small ball-shaped burr in my Dremel. Epoxy resin (or even kaptan resin - I'm using DevCon '2-ton') won't easily bond to glass-filled nylon, but will work well here as the two discs and adhesive will effectively encapsulate the nylon; the keying helps hold it all together until the encapsulation is complete (i.e. from tomorrow when I hope to fit the back disc). So here we are; 12 wheels with front discs fitted. We're about half way through the process, I think.
Roll on bed time. It's taken a great deal of effort (cutting spokes and keying the centres) and concentration (preparing gluing surfaces, keeping everything lined up, cleaning up the parts after gluing) to get this far!
More tomorrow, hopefully. I'll also try and explain where we are with 11001 and hopefully what's going to be involved in building the Class 12s.
Steph
This afternoon I started the model much as I usually do - by making sure many of the components are ready for assembly. In this case the obvious place to start was with the wheels, other jobs being done to fit around the effort and glue-setting times.
Here's the wheel showing how the original wheel (on the right) is hacked about and the front disc dropped in (left). The shape of the spokes really helps up by providing nice flat lands on which the disc can seat. Please note that this is the 'proof of concept' made up - the 'production' centres are in nickel-silver:
So after hacking all the wheel centres about they were then keyed using a small ball-shaped burr in my Dremel. Epoxy resin (or even kaptan resin - I'm using DevCon '2-ton') won't easily bond to glass-filled nylon, but will work well here as the two discs and adhesive will effectively encapsulate the nylon; the keying helps hold it all together until the encapsulation is complete (i.e. from tomorrow when I hope to fit the back disc). So here we are; 12 wheels with front discs fitted. We're about half way through the process, I think.
Roll on bed time. It's taken a great deal of effort (cutting spokes and keying the centres) and concentration (preparing gluing surfaces, keeping everything lined up, cleaning up the parts after gluing) to get this far!
More tomorrow, hopefully. I'll also try and explain where we are with 11001 and hopefully what's going to be involved in building the Class 12s.
Steph
Eastsidepilot
Western Thunderer
Nice work Steph, out of curiosity what was the wheel origionaly for ?.
Col.
Col.
mickoo
Western Thunderer
Dog Star
Western Thunderer
Steph,
In discussion with David White he suggested that I use a cyano for bonding metal to the nylon insert of Slater's wheels because of the hygroscopic nature of the nylon - hence the nylon "loves" cyano and forms a good bond. If you have tried cyano then please tell us the result. Indeed, please tell us why you have selected the noted epoxy product ('cos that would not have been my first port of call!).
regards, Graham
In discussion with David White he suggested that I use a cyano for bonding metal to the nylon insert of Slater's wheels because of the hygroscopic nature of the nylon - hence the nylon "loves" cyano and forms a good bond. If you have tried cyano then please tell us the result. Indeed, please tell us why you have selected the noted epoxy product ('cos that would not have been my first port of call!).
regards, Graham
iploffy
OC Blue Brigade
Because he's building two of them (post #13).
Kindest
Sorry can you pass my rain mac please
Steph Dale
Western Thunderer
I haven't a clue, but it's obviously an early prototype as it's representative of a wood or fabricated wrought iron wheel. The packet is marked 'Leicester and Swannington'.
You guys got it. That way I can be sure that building one isn't a fluke...
Graham,
I'm actually reasonably clued-up on adhesives and would have chosen cyano if I were sticking (for example) a balance weight onto one of Slater's wheels. However, cyano isn't particularly tough and is pretty hopeless in any structural application. It's also pretty hygroscopic and expands when it takes on water; so it's not stable either. Epoxy, on the other hand is pretty stable (DevCon 2-ton is aviation grade stuff), tough and strong. By the time I've finished assembling these wheels there actually won't be a continuous piece of the original wheel centre from hub to rim, so the adhesive/filler needs to be pretty strong, tough and bond well to nickel-silver.
The bonding of the adhesive to the glass-filled nylon is actually the secondary bond - once the wheel is made up the epoxy will encapsulate the major part of the original wheel, and I can then rely on mechanical locking of the adhesive to the nylon for the whole lot to stay together - assuming the bond to the front/rear discs remains good.
Oh and if you want a third reason then it's worked well enough on 11001...
Steph
Steph Dale
Western Thunderer
So this morning the wheels were all checked over and then it was time to prepare for fitting the back discs into the wheels.
To start with the back of the wheel was channeled out using my Dremel, mounted in it's stand and used much like a router, with a straight-sided dental burr. The edges then have a scalpel dragged round to clear off any 'rag'. The rear discs were then burnished with 150 grit emery paper to provide a good key. Assembly then progresses in small batches - they're all done now and I hope to provide you a photo once the adhesive has cured; at about 10:00 this evening...
Steph
To start with the back of the wheel was channeled out using my Dremel, mounted in it's stand and used much like a router, with a straight-sided dental burr. The edges then have a scalpel dragged round to clear off any 'rag'. The rear discs were then burnished with 150 grit emery paper to provide a good key. Assembly then progresses in small batches - they're all done now and I hope to provide you a photo once the adhesive has cured; at about 10:00 this evening...
Steph
Steph Dale
Western Thunderer
Faster than a speeding wassisname, I did take a shot of the wheels with the back discs in:
Which, as you can see, have rather less in the way of detail on their reverse sides. The next job (which I'll start in a few minutes is to bung a load of Milliput into the voids between the two discs. This will be wet sculpted whilst still soft so that I then have only to polish the surfaces with emery paper to makue up a set of 'good' wheels. There is further little job to do - filling the odd bit here and there to show where the balance weights have been cast into the voids in the prototype wheel.
And so thought turns to the body. One trick I've found over the years is that it nearly always helps to work from drawings larger than your chosen scale. Bit of a pain that for most of us Thunderers as most railway drawings are published at 4mm/ft. Thankfully the drawings I'm using are reproduced very accurately to 12mm/ft so the mental arithmatic becomes easy (1mm:1inch) and the drawings can be scaled down for use as templates. One other little trick here is to do a set of prints of said drawings onto tracing paper - that way you can drop the tracing over any parts to check for accuracy/conversion needs. And here's an example with the Class 12 cab drawing laid over the relevant fret for the Class 08. Unsurprisingly there are a number of differences:
So, shown here are a set of 12mm/ft drawings, their 7mm/ft counterparts on paper and an additonal set printed on film/tracing paper. Incidentally this isn't the full set of drawings of the Class 12 in the Wild Swan publication; there's a plan view included in this sequence of GAs. And further back in the book is a full Pipe and Rod diagram. That and the pictures means it's useful stuff.
Steph
Which, as you can see, have rather less in the way of detail on their reverse sides. The next job (which I'll start in a few minutes is to bung a load of Milliput into the voids between the two discs. This will be wet sculpted whilst still soft so that I then have only to polish the surfaces with emery paper to makue up a set of 'good' wheels. There is further little job to do - filling the odd bit here and there to show where the balance weights have been cast into the voids in the prototype wheel.
And so thought turns to the body. One trick I've found over the years is that it nearly always helps to work from drawings larger than your chosen scale. Bit of a pain that for most of us Thunderers as most railway drawings are published at 4mm/ft. Thankfully the drawings I'm using are reproduced very accurately to 12mm/ft so the mental arithmatic becomes easy (1mm:1inch) and the drawings can be scaled down for use as templates. One other little trick here is to do a set of prints of said drawings onto tracing paper - that way you can drop the tracing over any parts to check for accuracy/conversion needs. And here's an example with the Class 12 cab drawing laid over the relevant fret for the Class 08. Unsurprisingly there are a number of differences:
So, shown here are a set of 12mm/ft drawings, their 7mm/ft counterparts on paper and an additonal set printed on film/tracing paper. Incidentally this isn't the full set of drawings of the Class 12 in the Wild Swan publication; there's a plan view included in this sequence of GAs. And further back in the book is a full Pipe and Rod diagram. That and the pictures means it's useful stuff.
Steph
Steph Dale
Western Thunderer
In one way or another it's taken most of this afternoon, but I've now got all twelve wheels filled and sculpted. I ended up doing it in three batches as the Milliput was getting a bit tricky to deal with after working up four wheels.
The drill is to pack four wheel centres with Milliput and then go back to the first to roughly wet sculpt it. Once all four have been roughly sculpted I could then get in there with a wet V-shaped tool and get the shape refined.
The Milliput won't be fully hard until tomorrow, and then I'll get in there with some emery paper, fibreglass brush, etc. to put the finish on. And then it's on to the balance weights and they'll be ready for fitting. Pretty pleased so far:
Steph
The drill is to pack four wheel centres with Milliput and then go back to the first to roughly wet sculpt it. Once all four have been roughly sculpted I could then get in there with a wet V-shaped tool and get the shape refined.
The Milliput won't be fully hard until tomorrow, and then I'll get in there with some emery paper, fibreglass brush, etc. to put the finish on. And then it's on to the balance weights and they'll be ready for fitting. Pretty pleased so far:
Steph
Steph Dale
Western Thunderer
Grrr, they're still not ruddy finished. But it's a close run thing. I have managed to mould in place the balance weights in all wheels now (more on that tomorrow), but have realised that there's some horribly rough Milliput in some places which'll need re-filling. I've also got to build up the area around the rim on some of the wheels.
But we're nearly there. So much so, I've now started the finger singeing soldering. Yes, the filled wheels were placed on the amp to warm them up, Herbie Hancock came off, Ian Brown went on, the volume went up and I fired up the Antex. So this evening I've made up the front half of the coupling rods for both locos and should get the rear ones done over the next day or two. I'll have to make a little jig to form the joggle in the knuckle joint before I do that though.
So - immediate next steps are to finish the wheels with a further batch of filler and a good rub down. I'll also run wires down their backs for the split axle pick-ups so they can be blackened and painted in slower time.
The coupling rods will be made up, filed to finished shape/size and have oil pots, joint pins etc added.
And then I can start on assembly proper. The intention is very much to follow the instructions, making up the necessary parts to do the conversion to a Class 12 as I go. So saying, the coupling rods are not the first thing to appear in the instructions, but will be required for me to set up the chassis. I'm going to have to deviate from the instructions at that point anyway to get the Slater's insulated hornblocks in place for the split axle pick-up.
That'll do for now. Hopefully a little more tomorrow...
Steph
But we're nearly there. So much so, I've now started the
So - immediate next steps are to finish the wheels with a further batch of filler and a good rub down. I'll also run wires down their backs for the split axle pick-ups so they can be blackened and painted in slower time.
The coupling rods will be made up, filed to finished shape/size and have oil pots, joint pins etc added.
And then I can start on assembly proper. The intention is very much to follow the instructions, making up the necessary parts to do the conversion to a Class 12 as I go. So saying, the coupling rods are not the first thing to appear in the instructions, but will be required for me to set up the chassis. I'm going to have to deviate from the instructions at that point anyway to get the Slater's insulated hornblocks in place for the split axle pick-up.
That'll do for now. Hopefully a little more tomorrow...
Steph
Steph Dale
Western Thunderer
I realised this afternoon that I hadn't shown the tools I've been using for sculpting the wheels, so here they are:
The tool on the left has been used to form the balnce weights. The centre tool is the profiling tool for getting the angles between the front and back discs shaped and the dental tool on the right is what I used to pack Milliput into the wheel.
This shot shows how the balance weight tool is dropped into the wheel. It's wet at this point and so Milliput can be packed in to the bottom of each wheel cut out before removing the tool. So actually forming the balance weights nice and simply. It also helps that all wheels seem to have the same arrangement of balance weights, unlike the Classes 08 and 11, both of which have a larger balance weight on the centre wheels:
I've now mixed what I hope is the last batch of Milliput for these wheels. This has allowed me to smooth any rough patches in the existing surfaces. Once it's cured off I'll quickly knock up a sanding stick for any final polishing and then I'll likely declare them done.
Steph
The tool on the left has been used to form the balnce weights. The centre tool is the profiling tool for getting the angles between the front and back discs shaped and the dental tool on the right is what I used to pack Milliput into the wheel.
This shot shows how the balance weight tool is dropped into the wheel. It's wet at this point and so Milliput can be packed in to the bottom of each wheel cut out before removing the tool. So actually forming the balance weights nice and simply. It also helps that all wheels seem to have the same arrangement of balance weights, unlike the Classes 08 and 11, both of which have a larger balance weight on the centre wheels:
I've now mixed what I hope is the last batch of Milliput for these wheels. This has allowed me to smooth any rough patches in the existing surfaces. Once it's cured off I'll quickly knock up a sanding stick for any final polishing and then I'll likely declare them done.
Steph
Steph Dale
Western Thunderer
He he, probably not as patient as you might think. However, I'm not doing this in one hit and it's fitting in quite nicely as an hour to two, two or three times a week in the evenings. After a hard day at work doing something mindless after I've eaten is a good way to relax before bed...
Anyway, they're all done as far as the Milliput goes. I'm going to clean them up this morning, wire them and will post some pics a bit later. Now that the construction is sound I can do any further small filling jobs with something a bit quicker to use than Milliput.
And then I can crack on with the construction of the loco itself.
Steph
Anyway, they're all done as far as the Milliput goes. I'm going to clean them up this morning, wire them and will post some pics a bit later. Now that the construction is sound I can do any further small filling jobs with something a bit quicker to use than Milliput.
And then I can crack on with the construction of the loco itself.
Steph
Steph Dale
Western Thunderer
Patience is, apparently, a virtue. It also has its own rewards. Wheels done, construction starts in earnest this week. I've got a bit of an idea to get the wheels set on the axles with correct reference to the cranks, using a simple jig. With two of these locos to do, there's some sense in making use of small, quickly-made, simple tools for such jobs. Anyway, here's a pic of wheels, all ready for fitting...:
You'll note the wire down the back of the wheel, which is electrically connecting the hub and rim. It's a seperate piece of wire just in case I have an insurmountable problem with the split axles...
Steph
You'll note the wire down the back of the wheel, which is electrically connecting the hub and rim. It's a seperate piece of wire just in case I have an insurmountable problem with the split axles...
Steph
Steve Cook
Flying Squad
Brilliant bit of work Steph 
They look bloomin' marvellous, roll on the rest of the loco's
They look bloomin' marvellous, roll on the rest of the loco's 
lancer1027
Western Thunderer
Steph, they look SUPERB
. Already eagerly waiting for the next progress report ( with pics of course )
Rob
. Already eagerly waiting for the next progress report ( with pics of course )Rob