Monday, July 6, 2020

10HP Baguley: Step 6

Moving on to step 6 and we continue building up the cab area

Fix the cab floor to the white metal plinth making sure the planking detail is uppermost, carefully making sure the two parts are aligned properly as you may have issues getting into the cab a little later! Drill out the holes for the brake column and gearbox controls, the brake column is formed with a piece of 0.3mm wire and wheel, gearbox controls are formed from 2 lengths of 0.3mm. Now fix this sub assembly into place in the cab.
Gluing the two parts together was easy enough; there is no way I'm going to risk soldering white metal parts given the tools and skills I have. I then drilled out the holes (using a 0.4mm drill as I couldn't find my 0.3mm drill bits).

I did, however, solder the brake wheel to the 0.3mm diameter wire as I tend to find that soldering wheels to wire gives a much longer lasting join than using glue.

I trimmed the wire to length having test fitted the floor into the cab. I've deviated from the instructions (again) as I'm not permanently fitting the brake column or gearbox levers at this point as they'll by a nightmare to paint in situ.

Once I was happy that the floor fitted level inside the cab and that I could fit the brake column into the hole, I then glued the floor in place.

And with that done there are just two steps of the instructions left, excluding painting of course.

Friday, July 3, 2020

10HP Baguley: Step 5

Step 5 of the instructions is so short I almost didn't give it its own post but here it is...

Add the grab rails to the cab using 0.3mm wire, cutting them flush with the top. Trim back any protruding beading on the rear cab sheet.
As I said short and simple and it results in this...

And yes, before anyone mentions it, I do know I need to clean up the inside of the rear cab sheet. Not quite sure how it got covered in so much unused solder cream.

Thursday, July 2, 2020

10HP Baguley: Step 4

Right, let's have a look at step 4 of the instructions which read:

Take the front cab and bend the sides to 90°, attach to the footplate. Add the front making sure it lines up perfectly with the hole, followed by the sides.
Having read the instructions I decided to pretty much ignore them and go my own way. I decided that I'd probably find it easier to build up the front cab wall before attaching it to the footplate. I started by laminating the front overlay on to the cab before bending the part to shape.

No clever tools this time, just a cocktail stick and a scrap of wood to hold the two parts in alignment while I soldered them together. A little bit of cleanup where solder had leaked from the edges and the part looked perfect.

With the front overlay in place I carefully bent one side to 90° and then soldered on the overlay, before repeating the process for the second side overlay.

As you can probably guess the main issue with adding the side overlays was how to hold the parts while soldering. Folding just one side and the part is easy enough to tape to a piece of wood. With both sides folded this is more complex, but using an old wooden clothes peg worked really well. A little more cleanup and it slotted easily in to the footplate and could then be soldered into place to finish this step of the build

It may need a little filler on the corners but in real life it's less of an issue than in the cruel close up photo. Either way I'm happy with that and it didn't involve accidentally unsoldering anything from steps 1 to 3.

Saturday, June 27, 2020

10HP Baguley: Steps 2 and 3

Okay, so I know I said I'd do a post per step in the instructions, but firstly step 3 is very short, and secondly it appears I didn't take any photos of the finished step 2 so they are a bit muddled together. So without further ado here are the instructions for step 2:

Attach inner cab back to footplate with the half etch detail facing inwards, followed by outer cab back with the upper beading facing outwards, followed by the other buffer beam. Add 2 lengths of 0.5 brass angle @ 14mm to the half etch recesses, bend the upper cab beading to form part of the grab rails to 90°
Quite a bit more to do in this step than step 1, with quite a bit of laminating parts together to form the rear cab wall. The rear of the chassis has three small tabs which go into slots on the inner cab wall and while the parts fitted together perfectly I wasn't sure how best to hold them so they were at right angles (so the wall ends up vertical) while I soldered them together. In the end I settled on using a present I received last Christmas.

Yes, I was given a set of 1-2-3 blocks for Christmas and this was the first time I'd used them. Their weight meant they didn't move and nicely held the wall part in place, while I could also use them to ensure the two parts were at right angles to one another. Okay, so being metal they acted as a heat sink meaning I needed longer with the iron to make joint, but it worked perfectly, and no burnt fingers!

With the inner wall in place I then laminated on the outer wall and buffer beam, again using a coupling hook to help with the alignment. With the rear wall built up I thought it wise to check that the chassis still fitted before going any further.

It was more difficult to fit than before, so I've eased the half round holes I filed a little further, but other than that there were no issues at all. Now while I'm yet to finish step 2 of the instructions here is what step 3 says.

Form the buffer beam irons to shape, using the profile jig in the etch. Trim the excess material to length, in line with the half etch notches, fit these formed irons to both front and rear buffer beams, using the alignment marks.
After the hassle of trying to solder the brass angle to the chassis to form the valences I opted to superglue them in place this time. I also superglued the buffer beam irons as I didn't want to risk disturbing the buffer beam overlays.

The buffer beam irons were quite awkward to fit as I'd only just left enough room behind the Greenwich couplings. In retrospect if I was building the kit again I'd do things a little differently. I'd probably fill in the slot in the buffer beam, and then either solder a small upright section to the middle of the buffer beam iron, or maybe make a single piece version from brass sheet. In fact if I had any of my experimental etched couplings they might be a good starting point. I should point out this isn't a criticism of the kit, as the current version allows you to easily produce a prototypicalyl accurate model while having a slot for the couplings. It's just that the nice buffer beam irons get lost behind the coupling which seems a shame. I'm now in two minds as to whether or not to alter the model to remove the Greenwich couplings, any thoughts would be greatly appreciated.

Thursday, June 25, 2020

10HP Baguley: Step 1

For want of any other way of dividing up the build of this kit into separate posts I thought I'd go with a post per step of the instructions; so hopefully you can look forward to a further seven posts after this one and that's before I paint it.

Okay technically what I had to do first comes before even step 1 as the instructions for swapping the motor point out that you'll need to slightly file away part of the footplate etch to allow it to clear the longer motor and it's wires.

You can just about see that in the photo as I've filed two small half round notches in the footplate to help the wires pass through. You might also notice that I've added a small 3D printed piece to the front of the chassis (it's a light grey colour) so it becomes the right length.

Having done that I could move on to step 1 of the instructions for building the body.

Take the front footplate and fold the buffer beam to 90°. From the 0.5mm angle supplied cut 2 lengths @ 31.5mm and fix into the half etch recesses to form the valances of the running plate, file back any protruding material. Drill (gently) through the 4 holes for the grab irons in the brass angle with a 0.3mm bit. Attach buffer beam aligning with the coupling slot.
It all sounds simple enough and mostly it was. I choose to solder the kit together rather than using glue, and I did find attaching the valances to be really quite fiddly, as they kept twisting as I tried to solder them in place. I deviated from the instructions slightly as I choose to fit couplings at the same time as attaching the buffer beam overlay as that helped with the alignment. I'm not sure if the slot didn't etch fully (happens frequently with small holes) but I found I had to thin down the shank of a Greenwich coupling quite a bit before it would fit, but fit it eventually did.

Saturday, June 20, 2020

Flaws in Both Design and Manufacturing

With Canopus finally finished and a little modelling time opening up now that my son is back at nursery I had a look at what I could work on next. Now I do have a number of projects already on the go, but they all require some thought or scratch building. What I wanted was something a little simpler where I could just "follow the instructions". Looking through my stash of un-built kits and I've picked the Narrow Planet kit for the Baguley McEwan Pratt ‘677’ 10HP 0-4-0PM. This is actually the most recent kit I've bought, but as it uses a ready-to-run chassis should be a little easier than most of the other kits I have to hand. Famous last words!

The kit is designed to use one of the tiny Japanese N gauge chassis, specifically the TU-DB158 from TGW (Tsugawa). As you can see from this official diagram the chassis really is tiny.

While using a ready to run chassis like this does make things easier, I did know that I needed to do some work to it first, but it turned out to be a little more than I expected.

Firstly, as with many of these tiny chassis, the motor is not designed to be used with the standard 12V track supply. In fact the motor in this one is rated for only 4.5V. One option would be to fit a resistor to make it safe to use with 12V, but to be honest the tiny motor isn't brilliant and the kit instructions suggest changing the motor and recommends using a 0615 from Tramfabriek. This is actually really easy to do as you just need to unsolder the existing motor wires, slide the motor out, swap the worm gear from the old motor to the new, slide the new motor back in, and finally solder the wires on to the pickups. If it all goes smoothly then it would take probably all of about five minutes.

As you can see the new motor is a little longer, but given it will still fit inside the body then it's worth it to have a really good 12V motor in use. Now as I said that modification was nice and straightforward. Unfortunately there is still one design flaw and one manufacturing flaw that I had to deal with before I could move on to the body.

Let's start with the design flaw. The design work for the kit was almost completed when it was discovered that while the chassis would run fine on plain track it had a nasty habit of derailing when passing through point work. Both axles of the chassis are powered and so there is a series of gears linking them together. These gears are module 0.4 with 11 teeth and have a maximum diameter of 5.2mm. Unfortunately the wheels on the chassis are 5mm (excluding the flange) meaning that the teeth of the gears protrude 0.1mm below the top of the rail. On plain track that's not a problem but the gears catch on the rails when passing through points. I've no idea how this wasn't spotted during design, testing, or manufacture of the chassis, but clearly it's something that needs fixing.

It's difficult to see the problem, especially in photos, but with the chassis on the wrong tracks of my dual gauge (14mm and 9mm) test track you can just about see that the gear rests on the third rail and actually raises the chassis up slightly. The solution is fairly easy but you do have to be careful and take it slowly. Once I'd got the decent motor in, I secured the chassis upside down using some blutak and then with the wheels turning gently rested a small file against the gears to grind away the ends of each tooth. I think I've taken off enough to fix the problem, but the only OO9 points I have are currently a bit difficult to access in the garage. Rather than taking off too much I'll just revisit this later if it's still a problem.

While fixing the gears I spotted the manufacturing flaw, in that one of the wheels wasn't perpendicular to the axle. If it had just been slightly off I might have left it, but there was a serious wobble. Fortunately the chassis uses split axles, with each wheel only having a small axle stub which is fitted into the plastic axle. This means that I could remove just the single problematic wheel. Using a modelling knife behind the wheel it was easy to prise it off. I then removed the pin holding the coupling rod so that the wheel was completely separate to the chassis. It took me a while to find a way to hold the wheel that would also let me straighten the axle stub. In the end, I used one of the collets from my lathe, which highlighted just how bent the stub axle was.

I'm not sure what the wheel and stub axle are made from, but it's quite strong whatever it is, and took a fair amount of force to bend it. It's still not perfectly straight but it's the best I could do, as I didn't want to risk snapping the axle from the wheel. Once straightened putting the wheel back into the chassis was easy, but it took a long time to get the coupling rod pin back in. It's a tiny pin and it's a tight fit into the hole in the wheel. I tried lots of different ways of holding it and pushing it in and all failed. I had to be careful as the last thing I wanted was for the pin to ping off into oblivion. In the end I lightly superglued the pin to the end of a piece of acrylic rod and then pushed it home. As it seated itself properly in the hole the glue gave way leaving almost nothing to clean up.

After all that I was quite happy to see it trundling up and down my test track without any problems. It would benefit from a little weight (which the body will provide) but it runs a lot better than it did before I started to fix it, so I'm now happy enough with it to start work on the body.

Thursday, June 18, 2020

Alan Keef K12 Diesel: A Duplo Epilogue

As I mentioned in a previous post, my son loves playing with his Duplo. While his nursery was closed and I was looking after him we did quite a few of the challenges Lego posted on Twitter. Unsurprisingly trains came up a few times and it wasn't difficult to get him to build something.

On one occasions though, when I told him the challenge was a locomotive his answer was that he wanted to "build one like you did in the magazine". He was of course referring to the K12 diesel locomotive. He'd probably been reminded of it, because a day or so earlier the latest copy of the REVIEW had turned up and we had looked at it together, and the inside of the front cover was a full page Narrow Planet advert which included a photo of my completed model.

So we got the Duplo out and looked at the picture. Now I was a little concerned because I wasn't sure how he was going to do the wasp stripes. I shouldn't have worried though as he was adamant he wasn't going to add them. Which is fine of course because, as you may remember, only AK6 was fitted with the extra protection back and front onto which the wasp stripes are painted.

He started quite logically by finding all the orange Duplo pieces he has and then started to put them together. To say I had a very proud parent moment when he finished would be a serious understatement. Posed next to one of my prototype models that doesn't have the wasp stripes and I was very very impressed.

Okay, so I'm sure if he'd wanted to he could have built a better locomotive from his Duplo, but given the relative lack of orange pieces he had and the size of the pieces I think he did an excellent job. I think we're going to have a lot of fun doing modelling projects together when he's a little older.