Tuesday, April 12, 2016

More Brass Bits

Yesterday I finally managed to clear enough space (by temporarily dumping things elsewhere) to setup the lathe to turn a full set of spectacle plates. If you remember I ran out of brass after making one last time.

Armed with some new brass rod I set everything up and made a start on turning the 6mm rod down to 4.25mm for the outer diameter. My plan was to turn down quite a length of rod so that I could make four or more in sequence ensuring the outer diameter stayed the same. Initially I must have got the tool height wrong because as soon as I tried to take a small cut the tool dug in which tried to lift the front of the crossslide. While a little bit of pressure on the front of the crossslide stopped that happening the surface finish was terrible. So I stopped, made coffee, and then set everything up again. This time it was fine so I carried on.

The sequence was essentially to turn down the rod for the outer diameter, drill the central hole to 3.5mm (I would possibly have preferred this to be a little bigger but I was limited by drill sizes), face off and then turn down the end to 0.75mm to 4mm in diameter. This leaves me with a frame on the end of the bar which I then parted off. At that point I could just repeat the process from the facing off step to cut more frames.

I decided a photo of just four rings wouldn't be very interesting so instead we have a group shot of the main brass bits I've made for this model.


I actually made six parts, even though I only needed four. The first one I parted off badly which distorted it, and one pinged off never to be seen again during parting off leaving me the four I needed. This does mean that my success rate is climbing since I turned the buffers as two thirds of the parts were usable; it might even have been as high as 80% if I'd been able to find the one that got lost.

There will likely be a bit of a pause again as I'm getting ready for a work meeting next week that won't leave me much, if any, free time but then I have some annual leave so hopefully I'll be able to crack on with the final detailing and some painting...... although that would mean I need to settle on a colour scheme. I'm also not sure yet if I'll fit the window frames before painting, and then paint them brass coloured, or polish them up and fit them after painting. Anyone have any thoughts on which would look best? I'm thinking painting them might help me make them look worn and dirty as I don't want an ex-works condition loco.

Sunday, April 10, 2016

The Footplate

So far most of the work on making Skarloey look less like a cartoon character and more like the prototype it is based on, has revolved around detailing above and below the footplate. I have, however, been working for some time on the footplate itself. Specifically I've cut it into two pieces!

As you may remember, I've been working towards a model showing Talyllyn not as it is today but as it was in it's earlier pre-preservation life. So far that had meant moving the blower pipe to the drivers side, but I've now made a more drastic change by altering the footplate. Currently the locomotive has a footplate that runs along both sides of the boiler and encloses the tops of the wheels. Originally though there was no such footplate, with just a thin strip on the fireman’s side to give him somewhere to stand when topping up the water tank. To model this I've cut away the plastic footplate and added a thin metal strip which results in this.


It still needs some tidying up and a little filler in places but I think that looks fairly promising. You also notice that I've remove the box (I assume toolboxes although could be a sandbox I suppose) from the front right as again originally there was only one on the front left.

I think the main things left now are the remaining window frames and possibly a replacement chimney, but both require me fully reclaiming my desk again so I can get the lathe out. Hopefully that won't take too much longer.

Saturday, March 26, 2016

A Little Less Like a Cartoon Character

I hate having to pack away my modelling stuff when people come to stay as I never end up getting the space back quickly. This time it's been over a month since I last had anything to report, and in fact I've still not cleared my workbench. Mostly this is because work has been hectic, but we've also been trying to tidy the house a bit so keeping stuff on my desk has given us more room to work. Anyway, this morning I managed to grab a little time and space to do some more work on turning the model of Skarloey into less of a cartoon character.

As well as the face, the main problem with the model, as it comes, is that the cylinders are seriously over sized compared with the loco on which Skarloey is based. Also, probably as it's marketed as a toy, the crossheads are seriously chunky looking. Fortunately all these problems can be solved with Narrow Planet's new detailing kit. This kit is truly a joint effort containing parts from four different people, which improve the look of different aspects of the model. I won't necessarily be using all the bits in the kit but I've now fitted the new cylinders, slidebars, connecting rods, coupling rods, and crossheads.


It's once you get the original cylinders off the model when it becomes obvious just how big they are, or how small the replacements are in comparison. The new cylinders just slide onto the chassis, but the slidebar brackets and crossheads need soldering together before they can be fitted. Fortunately the etch design makes this really easy as you just align the outer frames using some cocktail sticks and then let solder wick between the layers. One thing you have to be careful with is that originally the brackets for the slidebars were plastic so it's important to make sure the metal replacements don't cause a short; hence why I've painted them and nothing else.


Fitting all the parts is very straight forward and the model is soon back running again. I made slightly more work for myself as in stripping the model right down (something you don't need to do if you are just fitting the detailing kit), I managed to have almost all the motor wires come loose -- the original soldering to the small board was shockingly bad. Anyway now I have the new cylinders and slidebar brackets in place I can start to build the rest of the bodywork back up.

Monday, February 29, 2016

Monocle

When working on the cab yesterday I realised that the rear windows didn't have any moulded surrounds. The front windows do have surrounds and I'd been intending to leave them as they didn't look too bad. As even old photos show rims around the rear windows I'm going to need to do something about them, so I think I'll now be replacing the ones on the front as well. On every model I've fitted window rims to they have been etched and while I could easily go that route I thought I'd see if I could turn them instead. Unfortunately after making the buffers I had just a tiny piece of rod that was roughly the right size left so as a test I made a monocle instead of a spectacle.


The hole in the cab is approximately 3.5mm so I opened this out to 4mm and then turned a rim with an outer diameter of 4.25mm and a central hole 3.5mm across that was a push fit in the enlarged hole. It probably needs for the rim to be slightly less proud of the cab and the edge rounded if possible, but as a first test this shows that the approach should work (a good job after I'd opened out one window hole already) so when the 6mm brass rod I have on order arrives I'll turn four rims rather than drawing up etch artwork.

Sunday, February 28, 2016

Replacing Moulded Details

One of the things that now often puts me off buying ready to run models is the inclusion of moulded details. While I understand that fitting details by hand to a model would raise the price above what was economically viable, I think they nearly always ruin the look of what may otherwise be a fine model. On Skarloey there are lots of moulded details; in fact I don't think there is a single detail which isn't moulded. Given I don't have to worry about damaging the paint finish etc. I've decided to really go to town and replace many if not all of the moulded details.

So far I've removed the following details from the model; rear lamp, rear lamp brackets, blower pipe, cab handrails, drivers side boiler handrail, the number plate on the cab rear, and a small disc like feature from the cab rear the function of which I'm at a loss to explain.


Of those details so far I've only replaced the blower pipe and cab handrails but already I think that dramatically improves the model. Interestingly I didn't just have to replace the blower pipe but I've moved it from the firemans side (where it is currently on the prototype) to the drivers side where it was pre-preservation. This also raises the issue of which of the other details I need to add back. For example, the only old photo I've found showing the rear of the cab doesn't show any lamp brackets or a number plate, although a drawing I have shows one lamp bracket rather than the three currently fitted. I'll keep looking for more photos before I make any decisions but if anyone knows when the extra brackets etc. were added or any other info about such small details it would be great if you could leave a comment.

Wednesday, February 24, 2016

Success Rate: 40%

The feedback on my first attempt at turning a buffer suggested that the problems with the surface finish were related to the speed at which they were being made. Specifically that I was probably turning the lead screw too quickly, but also that I might need to run the lathe faster than the 1500rpm I was using. I've now had another go using a faster lathe speed of 2450rpm while turning the lead screw much more slowly. This reduced the problem considerably although I notieced that the grooving was still present but was only happening when reversing the lead screw so was solvable by backing off the crossslide after taking the last cut to set a specific diameter. After a few false starts, mostly related to me not being able to count, I've now produced four almost identical buffers that I'm more than happy with.


In total I've turned 10 buffers giving me a success rate of just 40% but for my first lathe based project I don't think that's too bad at all. One thing I did learn is that I really want some resettable handwheels. In the end I resorted to facing off the brass bar until the dial read 0 so that it was easy to count out the other measurements along the bar. I also know I really want a collet chuck for holding small items as doing the final work with the buffer held in the 3 jaw chuck by the locating pin was fraught with problems and in one case I ended up with it clamped out of centre somehow which ruined the buffer when I added an off centre notch around the front face.

Anyway, I'm really happy with how these have turned out and in retrospect I'm actually quite impressed that the success rate is as high as 40%, I thought I'd go through a lot more brass than that before producing four usable buffers!

Tuesday, February 23, 2016

Third Turn's a Charm (Almost)

Having finished the boiler backhead and cab detailing (or at least the bits attached to the body casting) I've turned my attention to one of the other details of the original model which I think can be improved... the buffers. Certainly the loco is currently fitted with some rather distinctive buffers that have a circular core wrapped with a metal band as you can see in this photo.


If you remember back to the original model the buffer heads are just plain disks. Now no matter how skilled I might be with a file there is no way I could accurately file those heads down to represent the prototype and anyway given I own a lathe turning replacements sounds like a lot more fun.

I've actually been thinking about how to turn replacements for a few days, as having never turned anything without Paul's supervision I had to think about the best way of approaching them all on my own. In the end I drew a picture with dimensions and then a list of steps (on the left hand side, the right hand side is notes I made while turning the first attempt).


If you can't read my handwriting (sometimes I can't even read it so I wouldn't be surprised if most of you think it illegible) by plan was to basically work inwards in steps; turn the bar down to the max width of the head first, then turn down the rest to the width of the shank, and then turn down just the locating pin. The only complications being the slightly smaller diameter of the front and back of the buffer head. Turning the one on the back of the buffer head is easy, but the one on the front I decided probably needed doing after I'd parted off the buffer by turning the buffer around and mounting it on the lathe using the locating pin. After lots of careful measuring and turning I had my first attempt completed.


Unfortunately, just as with my first turning, I managed to loose some of the buffer head when parting off, so the head ended up being a lot thinner than I intended, so much so I didn't bother to re-mount it to do the final work on the front face. While it was far from perfect I had at least turned something so I set off to have another go. This time I managed to make the buffer head too big when parting off and when I went to try and rectify this with it mounted the other way around in the lathe, I got my handles mixed up and took off too much, so that was also a bust. On the third attempt though (I still parted off too much but I then faced off the buffer to thin it down) I produced something that dimensionally I was fairly happy with.


The shank could do with being a touch thinner but I could live with it as it is now. The main problem is that the surface is not very smooth. I'm guessing I've not set something up right as I basically end up with lots of grooves around the turning, which are easy to see in the photo and easy to feel as well. After my experience last time I made sure everything was nice and tight and as far as I can tell nothing shifted while in use. My guess is I've got the tool at the wrong height or angle, but I'm not entirely sure. Anyone have any suggestions as I need to figure out what I'm doing wrong before it's worth turning a full set of four replacement buffers.