Bill Bedford's New O4/5 Conversion Arrives

[Atlantic 3279]

I've only put this under a new title so as to draw attention fairly to the topic. For details of availability etc please see Bill's own thread, titled (near enough) "Add on Bits for RTR Locos".

Since the postman didn't arrive with this until about 11am today, I didn't open the box until 1pm, the state of affairs shown in these first photos was achieved by 4-30pm, and the work on this loco certainly isn't the only thing I've been doing this afternoon, you'll all be able to judge just how simple and quick this conversion potentially can be. Apart from de-oiling the 3D print, hitting it with a first coat of primer, making the fitting adjustments / corrections that Bill advises, finding out that a hair-drier with a suitable nozzle can also be used to persuade the plastic handrails to straighten, and discovering just how fragile Bill actually means that those handrails really are , I believe I have also solved the problem of how to make a reliable and detachable screw-fixing for the front-of-boiler-to-running-plate joint without interfering with the fit of other parts or with the ability to reinstate the original Bachmann superstructure if desired.
Okay, it was my day off work today and the wet windy weather nullified any daft plans for 10 mile country walks or for maintenance work on the car, hence I had time available, but how much simpler could anybody possibly want a loco conversion to be?
I'll go into more detail in a while, after eating, but here are the taster images:

[strang steel]

Excellent photos, thanks. Mine arrived this morning as well, but I have been too busy decorating to do anything other than take the body out of the packaging and admire it.

[davidwest]

Thanks for posting Graeme. I've an 04/8 on order

[S.A.C. Martin]

Looks terrific Graeme. I am waiting funds before ordering it myself. Will you go into the "de-oiling" process too? I've had a few 3D prints from various companies and they all seem to use different chemicals in the printing process

[rob]

These printed bodies are an outstanding concept superbly realised by Bill,these conversions deserve to be a big sucess....this will be beautifully executed by Graeme and I believe its biggest step forward since Hornby and Bachmann began to produce their new generation models....should broaden horizons very much indeed....looking forward to seeing this finished!

[Atso]

Wow, that looks excellent, full marks to Bill Bedford for getting this done!

Graeme, what do you think of the surface finish and any thoughts about cleaning it up? I usually use fine wet and dry mounted on a tiny rubber block (former moulds) and then finish up with a rub down with a glass fiber pen.

For degreasing I usually use a ultrasonic cleaner with a squirt of washing up liquid to remove the remaining waxy residue. This may take upto 3 or 4 runs before I'm happy that I've got rid of everything. Please use Halfords primer or similar as I've heard reports of some paints not taking to the surface too well - Halfords is fine and I've not had any problems using other paints on top of it.

[Atlantic 3279]

Time for some more details. It has taken longer to get this material ready than I had originally expected, so if I run out of time tonight I'll carry on tomorrow morning - it looks like I'll have some spare time.

As Bill points out in his instructions, the 3D print arrives covered in an oily residue. Wanting to get on as quickly as possible, and wondering just how tenaciously oily this stuff was going to be, I disregarded Bill's advice about using warm soapy water (note also the observation above about having to clean items several times even when using ultrasound). Instead I took a chance on the stability of the acrylic material and cleaned the whole lot down using plenty of white spirit and a soft brush. After blotting most of this off and letting the residue dry, I then thought it a good idea to further clean the surfaces with kitchen cream-cleaner and a soft-ish old toothbrush, prior to a final rinse and dry. The toothbrush soon broke one of the rear rails on the cab! It's a good job we have superglue....
Cleaned and dried, as shown below, the 3D print looks much more opaquely white and coarse / velevety than it did whilst still "oiled up". In fact the surface felt almost "sticky" in places, possibly to the rich texture, possibly in reaction to my spirit-cleaning. The primer went on well enough shortly afterwards anyway. Being a cynic, I'm tempted to wonder whether that oily coating is an inevitable and / or necessary consequence of the manufacturing process, or does the manufacturer (Shapeways I gather) use it partly because it gives the initial illusion of a smooth finish?
Here's the de-oiled item.

Despite deliberate use of a black background to try to emphasize the edges of the white subject, this is the best image I managed from my auto-focus camera!

[Atlantic 3279]

A blow over with Halfords primer produced this, much easier to photograph and cruelly emphasizing some of the unwanted surface texture which seems particularly pronounced only above handrail level on only one side of the boiler. Some other areas are very very smooth, and it seems not to depend purely upon whether the ares are flat or curved.

That must do for tonight. More tomorrow, and I'll try to remember to post up a picture of "Thompson's Turbomotive" elsewhere too.

[2002EarlMarischal]

A blow over with Halfords primer produced this, much easier to photograph and cruelly emphasizing some of the unwanted surface texture which seems particularly pronounced only above handrail level on only one side of the boiler. Some other areas are very very smooth, and it seems not to depend purely upon whether the ares are flat or curved.

Really helpful Graeme thanks. I assume mine is in transit having jumped onto the bandwagon as soon as it became available on the Mousa website, and I am very much looking forward to receiving it.

I'm surprised so far about 2 aspects - the oily coating, and the irregularity of the surface finish - it will be interesting to see if we all have the same manifestation or whether it varies from body by body. Fascinating stuff, and I feel we are very lucky to have the opportunity to benefit from this pioneering technology - many thanks to Bill for his efforts.

As the late, great Sid James would perhaps have said "carry on trailblazing!"

[jukebox]

Interesting that the underside surface seems to be a lot more refined - look at those smokebox saddle rivets; perhaps the model needs to be "inverted" and printed from the opposite side to that which it is now?

Also - taking nothing away from the idea, as I think it is excellent and applaud it 10,000% - surprised at the inclusion of handrails, pipes and smokebox handle cast in resin - whilst I understand the driver that this should be "plug and play", I would have expected the target audience would be able, and want, to roll their own for addtional fidelity.

All very exciting stuff, and a peek at what may well be the future of limited run models!

[Atso]

Hi all,

The oily residue is a result of the printing process as the material is supported by a wax layer which stops hollow sections and undercuts collapsing while being printed. When the model is removed from the machine it is a block with the wax on the outside and the model protected within. This wax is then removed by applying a low heat but leaves the residue noticed by Graeme.

I have to agree with Bill's instructions that the best method of removing the wax layer is with soapy water some others using Shapeways have noticed that other methods have caused problems with the model (although I don't recall white spirit being one of them).

The layering effect is a consequence of the printing process and cannot be avoided (at least not at an affordable cost). I suspect that others will notice that the layering is more visible in places other than shown in Graeme's pictures. This is due to the orientation the model is printed in and as a result one side will always be more defined than the other. Nothing to worry about though as some careful work with various grades of fine wet and dry will remove this.

I usually coat the model with two different Halfords primers, red and grey (never white as it doesn't seem to like the plastic!) and then start rubbing down. The two coats show how far I've rubbed as well as showing up on any further rub downs afterwards. Please try and avoid filler primer as I've never successfully used it on a 3D print without obscuring detail. However I do find that as you approach a smooth finish a light top coat of Halfords car paint (Brooklands green in my case as that's what I've got to hand!) can often help with this final stage.

I am watching with interest how this develops and look forward to seeing some excellent models!

[Atlantic 3279]

The lack of adverse comment (so far) about white spirit comes as something of a relief.....

I'm leaving the printed handrails etc in place for the time being so that we can all see what they are like, and see how quickly the resultant model can emerge if they are left alone. I am fairly certain that I will replace them in metal however, since they are both phenomenally fragile and (I feel) over-scale in thickness.

Before I carry on with the main theme, I'll say what I discovered about straightening the handrails with a narrow flat nozzle on a hairdrier, before bending them again under subsequent body-handling pressure! I directed the stream of hot air at right angles to the length of the boiler, directly onto the bent section(s) of handrail, from either above or below the handrail, so that as far as possible the flat layer of hot air was flowing over the handrail but missing the boiler itself. I had to apply what seemed like quite a lot of heat, whilst watching like a hawk to see whether anything disastrous was starting to happen. I noticed three things, two of which seem slightly contradictory, but I can only report what I observed. I have nothing more to add to this:
1. Sometimes the handrail would straighten whilst the heat was being applied, the sag of the original curve apparently having to be "upstream" into the flow of hot air in order to straighten out. For such thin material it seems surprising to me that one side would get hotter than the other by a sufficient amount to cause differential contraction, but who am I to know such things? Maybe it was just the airflow blowing the softened handrail towards the straighter line?
2. In other cases the handrail did nothing until the heat source was removed!?!? Fathom that one out.......
3. Sometimes it was necessary to orientate the work so that gravity assisted in straightening the handrail, otherwise it just remained bent or the sag got even worse.

[2002EarlMarischal]

I have to agree with Bill's instructions that the best method of removing the wax layer is with soapy water some others using Shapeways have noticed that other methods have caused problems with the model (although I don't recall white spirit being one of them).

All these tips are very useful gentlemen. I wonder whether for soap one could substitute "Fairy Liquid"? As I understand it, this cuts the grease from dirty pots and pans. Perhaps it might be gentler than white spirits but more effective than every day soap?

[earlswood nob]

Good morning all
The O4/5 looks good already.
I am going to have to get one. I have recently built an O4 chassis to replace a Kays nuclear proof original, if I construct a brass footplate using GK's methods it would only need plasticard splashers to complete a new loco. A tender is available from Dave Alexander to finish the model.
Musing whilst walking this morning,it should be possible to produce an O4/4 from the O4/5. It would need the boiler & firebox lengthening and the cab shortening and a soide window fitted.
The scratch chassis would have to be slightly longer and the plasticard spashers would be different.
A further thought would be to purchase the Bachmann O4, use the Bill Bedford body to produce an O4/5 and convert the original body into a B4 or C4 which had a similiar boiler.
Such are dreams
Earlswood Nob (a signalbox near where I grew up)

[mick b]

Re handrails sounds like it shrunk as it got cooler, and pulled itself straight ?

I think I would also go for metal handrails, it will also make cleaning the Boiler up so much easier to do. Dont like the look of the Smokebox door handle much either , looks a bit weird?


Re cleansing the body, how about washing up liquid and Cif ?. I always use on all my models without any problems.

Are these mouldings porous?, if yes I would not use white spirit on them personally, as very slow to evaporate and is oily too.


Just acquired a O4 which I want do as a O4/8 will wait to see how this progresses , before either using a Bachmann B1 for the conversion or a Bedford