Loco building - Do I have what is needed?

[jhockuk]

I am very keen to get on and build my first standard gauge 7mm loco (I have built a couple of 014 loco's), I want to be sure I have what I need before I start.

The loco I have to build is an 0-6-0 Judith Edge Sentinal, I have the kit, wheels, gear box, motor and buffers, so that should be it.

Tools?

I am OK when it comes to soldering but what concerns me is the building of the mechanisem.

When building the 014 loco's I ended up buying a GW wheel press, as this kit uses Slaters wheels that are already on the axles I can only assume I will need to take them off at least 1 axle in order to fit a gear to that axel. All the 014 loco's have been 0-4-0's and had no rods so no need for quartering.

Does that mean I need a wheel puller and wheel press suitable for 7mm loco's?

If so do such things exist?

Quartering? What do I need to achieve this, it seems to be some sort of dark art...Will this require taps and dies?

Sorry for all the questions, I am quite new to all this and would really like to have a loco up and running, but before I start I want to make sure I have what I need to build the model.

James

 

[Dikitriki]

Hi James,

Why don't you post a photo of the wheels, then we can advise you properly?

If they are 'normal' Slaters' driving wheels, there is no need for wheel pullers or quartering devices.

The hesitation I have is that you say they are already on the axles, which is not usual for Slaters.

Richard

 

[Dog Star]

A perusal of the Judith Edge catalogue notes that the Sentinel 0-6-0 engine is (a) outside cranks and (b) supplied with 14mm disc wheels (which is probably for the 4mm kit). If the wheelsets come from the Slaters C&W range then the wheels are supplied mounted on a shouldered axle.

Given that the engine has outside frames, the key question seems to be "how are the cranks secured to the axle?" and that then dictates how the cranks are to be quartered.

regards, Graham

 

[Oz7mm]

James

Wheels pullers do exist and I have one here. I see you describe yourself as being from deepest darkest Hertfordshire which would well describe my address. I don't know if you can make contact off line on this forum but if possible please do so and I would be happy to assist you where I can if you're indeed just up the road

John

 

[jhockuk]

Thank you gents.

I will post up some pictures this evening of the wheels and read the relevant parts of the instructions and post up what it says.

 

[Scale7JB]

You may need some pickups too, to finish the engine..

With a little cleaning up, I get on very well with the Slaters plunger pickups. Ideally if I can I use split axle pickups, but that's a whole other new skill and mindset..

JB.

 

[Steph Dale]

James,
If you can post photos of what you've got then I'm sure the expertise is on this 'site to help you.
You already have the most important thing to build a working model; you're prepared to pitch in and have a go and unafraid to ask questions...!
Your only problem here might be deciding which solution to follow up on as you're bound to get several for any problem you post.

Number of solutions = number of problems x (number of people present + 1)

Steph

 

[jhockuk]

Sorry it has taken a while but here are some pictures of what I have:

 

[adrian]

Hi,

I'm confused with the wheels supplied and whether they are suitable for the kit. These might be ok for the 0-4-0 sentinel but as Graham mentions the 0-6-0 is an outside crank loco if it's this one http://www.ukmodelshops.co.uk/judithedge/kit/117.

What is supplied in the kit for the outside cranks? are there any axle extensions?

For the wheels you show then you will need to take one wheel off to fit the gearbox but I'm still trying to work out where the bearings fit because if it's the outside crank Sentinel then where are the axle bearings. Is it a dummy inside chassis?

 

[Dog Star]

James,

The Slater's wheels have an axle of 1/8" diameter and that is compatible with the Branchlines gearbox) based upon what is written on the card backing for the Multibox parts.

What Adrian has written is key to the original question... how are the wheels supported in the frames and how are the cranks attached to the wheels? Please take photos of the relevant parts of the instructions / parts so that we can see how this kit is to be assembled.

regards, Graham

 

[jhockuk]

With any luck this should explain, but from what I can tell, there are axle extensions and open bearings are supplied with the kit.



I have taken pictures of the relevant (I think parts of the instructions).





I think I am OK to publish them as only the diagrams in the instructions seem to have a copy right attached to them.

If not I will remove the pictures from the post.

 

[jhockuk]

I am slightly less worried about the wheels than I was as the axle design means they should stay in gauge and be easy enough to get back on, from what I can tell.

 

[adrian]

Hi,

It all becomes clearer now, I suspected there must have been some axle extensions as it was supplied with the coach wheels.

So yes before you fit the extensions then you will need to fit the gearbox to the axle.

As the quartering seems to be done by just soldering on the cranks in the right position, there are no positive locations for the quartering so there will be a bit of trial and error but nothing too difficult. From the instructions I presume it's going to be a rigid chassis.

Although the instructions say epoxy the extensions onto the axles if the fit is close then I'd be tempted to use Loctite rather than epoxy. In my opinion it's a cleaner finish and stronger bond. I'd also use Loctite on the wheel you removed, the coach wheels are push fit on but once removed they don't go back quite as firmly so I put a spot of Loctite on. Just beware that once the extensions are fitted then you won't be able to remove the wheels. Again another reason for loctite in that it will break it's bond with a bit of heat. So if you do need to remove them a touch with a soldering iron will allow you to remove the extensions.

 

[Dog Star]

Hi James,

Asking questions on WT is a good thing, how you deal with selecting an answer that is appropriate is up to you.

Your most recent photographs of bearings and journals plus instructions are most useful and put the kit design into context. As I read the material, the kit designer has intended the builder to use Slater's standard Carriage disc wheels which have an 1/8" axle and pin-point journals - the kit provides bearings for the inner loco frames and that means that one wheel needs to be removed from each axle. An axle is machined with shoulders to maintain the back-to-back for a wheelset so you shall have no problem in either removing or fitting wheels to from/to axles. The turned axle extensions are to fit onto the end of the axles once the wheels have been fitted permanently into the frames - the use of epoxy to retain the turnings on the axle means that disassembly of wheels is not possible (easily... WTers can achieve the impossible) after fitting the extension pieces.

Turning to your original post... the instructions mention that the inner bushes need to be "fitted: to the holes in the inner frames and that use of a reamer is recommended. A search of the Squires on-line tool catalogue is going to help to find something suitable.

You may wish to consider obtaining several lengths of 1/8" silver steel rod for use when fitting the axle bushes into the inner frames... and this may require use of a 1/8" taper reamer.

I do not see the need for a wheel press nor that a wheel quartering jig is going to help you with this style of frame / wheel construction.

 

[jhockuk]

Thank you guys most helpful responses. Time to get on with kit I feel.

It will be a challenge for me but from what has been said none of the processes involved seem to taxing, so patience and persistence should pay off.

Adrian, thanks for the tip about loctite and heat, I have to make some adjustments on an 014 bent frame Simplex I am building and I have used loctite on the gears, now I know they can be adjusted I feel much better.

Now to fire up the soldering iron...

 

[SimonT]

James,
for what it is worth, here are some photos of my Sentinal.


In the view above of the chassis installed in the body, you can see that I have given the centre axle a small amount of movement which I have sprung. You can also see how one wheel on each needs to be removed to thread through bearings or gearbox. The wheel is then replaced on the axle.

This view will hopefully give you an idea of what the finished chassis will look like. Being a Mike Etch design, the chassis went together straight and true, so hopefully yours should do too.


The pick ups are a mixture of back scratchers and rim scrapers.

With a crank pin removed you can see how the axle builds up. Solder the laminations together to make the crank, tap the crank pin hole 10BA and then solder the crank to the axle extension (at the moment I cannot remember how I ensured they were all true other than trial and error). The extensions are secured to the coach axle with Stud Lock on one side. Quartering was done by eye using screw lock on the unsecured axle extension. Screw lock parts easier than Stud/Bearing Lock

I hope this helps and look forward to seeing your build.

Simon

 

[jhockuk]

Thanks Simon, most helpful.

So I am going to need a 10ba tap in order tap the crank so I can attach the crank pin?

 

[jhockuk]

A quick read of Wikipedia reveals there are 3 types of tap...

I think a tapered tap would be best as this is a very small hole?

I really wish they had made more of engineering when I was at school!

 

[adrian]

The type of tap to be used isn't really governed by the size of the hole, although I can see where a tapered tap might be easier.

The hole should be drilled to the 10BA tapping size and then use the tap. Personally I have few taper taps, I mostly use 2nd taps. As long as you hold it square then you can get a 2nd tap to start the thread quite easily. The taper taps need a lot more turns to get the thread fully formed because you need to feed it in further. With these small details and soft metal then I think to some extent using a taper tap with the extra turns gives you more opportunity to mess up the thread so I'd recommend a 2nd tap. You can always practice on a few of the scrap etches to build up confidence. Avoid the plug taps, these are really for finishing off blind holes which you would have started with a taper or 2nd in the first place. As the hole is open all the way through then a taper or 2nd is fine.

Even though you shouldn't need to with brass always remember to back off a third when cutting the thread to remove the chip. The tap is cutting a groove in the metal and will block up the tap so turn a quarter or third to cut the thread or until it gets stiff and then back off a third, the back of the cutting edge then knocks off the chip and makes the next cut easier. Again you can get cutting compound to make it easier, for brass you can get away without it really but I'd recommend it if you were threading steel. A small pot will last a lifetime.

 

[D G Williams]

If Adrian doesn't mind me adding my tuppence worth - the recommended 10BA tapping size drill is No 54 or 1.4 mm. (See table 7 in 'Drills, Taps and Dies' by Tubal Cain). Backing off when cutting the tread is essential, especially when using tiny taps - and a light touch is advisable. (No prizes for guessing how I know this!)
Happy New Year from David