Silver Fox 4 COR Conversion

[3283 Comet]

I am building a 4 COR EMU for a friend who has wanted one for quite some time. We had hoped that one of the RTR manufacturers would make one, but it hasn't happened. So when I saw the Silver Fox conversion kit I offered to build it, and here we are. The kit is made to convert four Bachmann Bulleid coaches, which as it turned out, another friend had spare and was willing to part with. However recent events being as they are I wont be seeing my mate for a while, and thought that posting some pictures on here would be a useful way of keeping him informed of progress with the build. Now this isn't going to be a five minute job, and will probably take most of this year to complete, as I will have to complete this i between all of the other calls on my precious spare time. As this is my first post hopefully all the photos will appear and in the right place, we shall see....

 

So to start with I thought I would make the drive unit, and test it works with all four coaches before I cut everything up. The power unit is a Hornby 5 BEL motor bogie bought from Peters Spares, which should be more than good enough for a 4 car unit. 

 

Donor Coach for this is a Bachmann Bulleid SO

  

 

Here it is taken apart, which is  pretty easy once you know how. I found the trick is to get the middle clips out first, on one side, and it just about falls apart.

 

The underframe has to be seriously altered, and everything below the solebar has to go. This is what is looks like at the start.

 

and this is what it looks like once its all gone, no turning back now....

 

Next was a hole for the motor bogie and mount, this took a while to make sure I was happy with the location, as the bogie centre is different than on the donor coach. But comparing to drawings and checking a few measurements i think its about right.

 

 

and finally for now a start made on putting it back together. Two pieces of plastikard are provided for the sides of the motor mount, along with a clear perspex top. I fitted the sides, and will now wait until the glue is fully set before attaching the top, and checking the ride height etc.

 

  

 

So that's it so far.A long way to go but a start has been made. Hopefully I can get a rolling chassis completed in the next few weeks, so i can test it out with the other 3 coaches. 

 

Comet

 

[5Bel]

Hi Comet,

 

I will be following this topic closely as I have one to do. Will be interesting to see your methods.

 

Cheers for now, Ian

[MarkC]

15 minutes ago, 5Bel said:

Hi Comet,

 

I will be following this topic closely as I have one to do. Will be interesting to see your methods.

 

Cheers for now, Ian

Me too. I will be building a Class 124 using Silver Fox sides and ends. I've already got other 'how to' guides, but other ideas are always welcome

 

Good luck

Mark

[3283 Comet]

Thank you Mark and Ian for your comments. As I haven't made one of these kits before i am sticking quite close to the instructions included in the kit (for now at least), but they are quite brief, and I have not fully understood some of them. But in general the conversion looks relatively straight forward, and i am quite used to kit building.

 

So only a small amount of progress today. The sides for the motor bogie mount had glued pretty solid, so i decided to glue the top on. The top is a pre-drilled piece of clear plastic, but when i looked at it, the hole didn't appear to be in the centre. Out came my ruler, and it proved my eyes weren't wrong, it was about 1mm off centre. Now that doesn't sound much, but it might spoil the look of the unit stood on the track when looking at it face on. So i made a replacement from 60 thou plastikard. Not wanting to repeat the same mistake I drilled the hole in a slightly larger piece and trimmed the edges to the correct size, thus making sure it was in the centre, or as close as could get it. 

 

I also made two small strengthening pieces to glue inside the corners, as I was worried the weight of the motor bogie would be reliant on one small joint. I have glued it all together using Plastic Weld, and it is now under a light weight until it is fully cured.

 

I will post a photo of the completed piece when I get some natural light on my work bench. When it is glued hard it will also allow me to check the ride height and see what, if any adjustments are required.

 

Comet

 

 

[3283 Comet]

The motor bogie mount has now been completed, although it did take two attempts. When I attached the top plate to the sides the chassis was around 1.5mm too high. After much measuring, checking, and head scratching, I took the decision to take the top plate off and add a 60 thou packing piece. This seem to have solved the problem. 

 

 

 

The chassis sits a little low, but I can add washers to adjust this. I have now wired up the power bogie, and had it running up and down a few yards of track. It seems to work fine, even without any additional pickups or weight. The next job will be to add some weight around the power bogie and try a load test with all four Bulleid coaches. I am planning on adding additional pickups to the trailing bogie, but i haven't fully decided how to do that yet.

 

Comet

 

 

 

[roythebus]

I'd have thought it would be easier to chop up Maunsell coaches to make the Nelson? Far nearer the body shape than the Bullieds. but then the conversion kit was probably designed before the Maunsells were introduced.

[SRman]

1 hour ago, roythebus said:

I'd have thought it would be easier to chop up Maunsell coaches to make the Nelson? Far nearer the body shape than the Bullieds. but then the conversion kit was probably designed before the Maunsells were introduced.

 

I thought that at first, too, but then remembered the Maunsell loco-hauled stock is only 59' long, so there would still be a lot of hacking and joining to do.

[John Tomlinson]

On 22/03/2020 at 14:58, MarkC said:

Me too. I will be building a Class 124 using Silver Fox sides and ends. I've already got other 'how to' guides, but other ideas are always welcome

 

Good luck

Mark

And another one, I have a 119 to be built in a similar way.

 

You seem to have made a sound start with the power unit.

 

John.

[3283 Comet]

18 hours ago, SRman said:

 

I thought that at first, too, but then remembered the Maunsell loco-hauled stock is only 59' long, so there would still be a lot of hacking and joining to do.

 

This was something that was discussed when i first saw the kit. The Bulleid coaches have a much more curved profile and not the slab sided look that the 4 COR units had. Before the donor coaches were acquired I read through the instructions and the flattening of the sides, or what remains of them, is addressed. I had assumed (not being a die hard SR man) that the 4 COR unit would have been based on Maunsell coaches, but in fact the four coaches are longer at 62' 6" over the headstocks. So the Bulleids are a better starting point as long as I can get the correct profile to the sides.

 

I will start looking at the body conversions once I am happy with the running of the unit. Testing will get underway in the next few days, time permitting.

 

Comet

[roythebus]

OK thanks.

[number6]

Interesting. Surely the only thing in common between a Bulleid coach and 4COR is the colour?! I think you should create a fantasy Bulleid EMU - an express version of the 4Sub instead. In all the imaginary loco threads has anyone sketched up something like this? Follow the end profile look at a Sub and add a corridor connection... 

 

Good luck anyway!

[BernardTPM]

Both the roof (slightly shortened) and trailing bogies would be the same. That's the bulk of what would be used in the kit, I should think.

[dasatcopthorne]

Please take this constructively. You need the mainframe from the Brighton Belle as in  the pic. Also remember that  no SR EMU had shoebeams quite like Hornby's version. 

 

 

Edited March 27, 2020 by dasatcopthorne

[3283 Comet]

On 27/03/2020 at 12:34, dasatcopthorne said:

Please take this constructively. You need the mainframe from the Brighton Belle as in  the pic. Also remember that  no SR EMU had shoebeams quite like Hornby's version. 

 

 

 

Yes, you are absolutely right, the power unit I have is the correct type, but has a different bogie frame on it. The kit comes with sides for the two bogies at each end of the unit, which are the same as the Hornby 5BEL type. But to use the bogie sides will require some significant modification to the existing frame, so I am looking at options for this. The spare frames are out of stock at present so I might wait and see if I can get one later. Im in no hurry as this kit will no doubt take me a while to complete. I think for the non- powered bogie I will make a new frame from plastikard to accommodate the sides in the kit, rather than graft them onto one of the Bachmann bogies as is suggested in the instructions. 

 

Thanks for the info about the shoebeams, I will have to look through some of the pictures I have to see if I can match the prototype.

 

Comet  

[3283 Comet]

I have completed the load testing, and after trials with various different weights I concluded that the minimum I will need is between 150 - 180g of additional weight in the power car. I tested the power unit with the 3 un-modified Bachmann coaches on a 1 in 40 gradient, which is similar to the ruling gradient on the layout that this model will be used on. I loaded the power unit with car wheel weights, and with 120 grams it would work, but there was some slipping, particularly when restarting on the gradient. On the flat it was fine. So I added further weights to bring the load up to 180 grams and it worked fine, and will crawl on the gradient at low speed without slipping.

 

I have to say the Hornby power bogie has plenty of grunt, and works really well, but is geared a little high for my liking. The testing also confirmed it could also use additional pick ups from the trailing bogie, once i work out how.

 

I will make some weights from lead sheet to fit around the power bogie, and see if i can reach the weight required.

 

Comet

[Robert Shrives]

Good to read of progress - a case of Cor - blimey I suppose!  I was looking at an N version with Electra printed sides on mk1 sides so hopefully slab sides versus  curves not so pad in N .. 

 

Robert  

[3283 Comet]

I have now glued in place enough lead to make up the required weight. It does block some of the windows of the guards compartment, but there isn't much choice if you want weight over the driving wheels. I also decided to replace the original coach weight with a new one from lead sheet. This way I have managed to get about 240g of additional weight into the driving unit, most of which is right over the power unit.

 

 

I have tested the unit with the other 3 coaches and it works really well. I also attached another 4 coaches to the rear and it happily pulled those up the gradient too. So if a 4RES happens to appear that can be attached without a problem.

 

Next job is to fit the underframe detail and its ready for painting, which will be done once i have the other 3 coach underframes converted.

 

Comet

 

[3283 Comet]

I decided that before I finished the delicate detail in the underframe it would be better to make sure the refurbished coach body fitted the chassis. So I have started the conversion of the body for the drive unit. First job was to remove all the raised detail on the sides which was done with a flat blade and a light rub over with fine emery paper. 

 

 

The detail above the windows was removed once the window had been cut out, which was easier. The removal of the tank on the roof was more tricky and involved some serious filing and scraping with a blade. The vents came off quite easy, although care was needed to avoid stabbing myself with the blade, as a lot of pressure is needed to get through the tough plastic. 

 

 

With this done i cut out the windows using a metal slitting disk in a mini drill, which did the job very easily. The instructions suggested removing all the windows along the entire length of the coach except for the ends, but i was worried this would leave the remaining coach very weak. The overlays are very thin and wont give much structural support to the coach body on their own. So i left two additional supports in places that missed he windows. 

 

 

I then filed the remaining vertical supports flat to remove the Bulleid profile, and make the vertical profile required for the 4 COR. I glued the sides on with impact adhesive, although i was careful not to put too much on, as the plastic of the overlays is thin and I didnt want the glue to affect the sides. This process was quite simple, the new sides stuck well to the original coach. I then made the required adjustments to the roof, although I preferred to remove the end of the roof and take off a further 2mm to allow the end to be stuck back on. This was easier than trying the cut the roof to the required bow ended profile. As you can see I needed a slither of 20 thou plastic to get the roof to join up correctly, 

 

 

The ends did need a little work to make them match the body, and i am still not happy I have everything aligned perfectly. I plan to give the body a thin coat of primer which should show up any imperfections and I can fill / sand those areas. The ends still need some details adding such as pipework and corridor details. As you can see the weight around the motor shows in the first vestibule and the luggage area, but all the passenger compartments and the driving end are clear. At least its beginning to look more like a 4 COR now. 

 

[DJDAVE]

Looking good Mate!

[John Tomlinson]

I'm interested in how you've applied the overlays.

 

The instructions with my Silver Fox 119 seemed to imply that having cut out the windows on the base shell, you should then glue in the clear perspex, to reinstate the integrity of the shell, then glue on the overlays. Working in this order, then logically the overlays should be painted before you glue them on, or else you are faced with a hideous masking job!

 

By leaving some of the window level plastic on the original coach you've taken a more traditional approach to the problem, and as long as the overlays aren't so fragile as to be damaged before you get to putting in the perspex, this approach should work.

 

John.

[3283 Comet]

6 hours ago, John Tomlinson said:

I'm interested in how you've applied the overlays.

 

The instructions with my Silver Fox 119 seemed to imply that having cut out the windows on the base shell, you should then glue in the clear perspex, to reinstate the integrity of the shell, then glue on the overlays. Working in this order, then logically the overlays should be painted before you glue them on, or else you are faced with a hideous masking job!

 

By leaving some of the window level plastic on the original coach you've taken a more traditional approach to the problem, and as long as the overlays aren't so fragile as to be damaged before you get to putting in the perspex, this approach should work.

 

John.

 

Having read them again to check, it appears that the instructions for the 4 COR are different, perhaps due to the ends having to butt up to the sides. The glazing is the last part to be fitted to the body in the instructions I have. I did vary form the method given in the instructions, as it was suggested to stick the sides on with double sided tape, but i preferred to use impact adhesive, as i just didnt think that tape would be up to the job, and there is only a very small area at the top of the sides left to stick too. 

 

I have to say, having done this one coach, I wouldnt like to paint the side first before sticking it on, as I have needed to apply small amounts of filler to make the joins at the ends as seamless as possible. Rubbing down the filler would ruin the paint job. I always prefer to add glazing last if possible as it makes painting so much easier.

 

The overlays are robust enough, and if you can leave in a few extra uprights between windows it definitely helps keep the whole thing more rigid.

 

Comet  

[John Tomlinson]

55 minutes ago, 3283 Comet said:

 

Having read them again to check, it appears that the instructions for the 4 COR are different, perhaps due to the ends having to butt up to the sides. The glazing is the last part to be fitted to the body in the instructions I have. I did vary form the method given in the instructions, as it was suggested to stick the sides on with double sided tape, but i preferred to use impact adhesive, as i just didnt think that tape would be up to the job, and there is only a very small area at the top of the sides left to stick too. 

 

I have to say, having done this one coach, I wouldnt like to paint the side first before sticking it on, as I have needed to apply small amounts of filler to make the joins at the ends as seamless as possible. Rubbing down the filler would ruin the paint job. I always prefer to add glazing last if possible as it makes painting so much easier.

 

The overlays are robust enough, and if you can leave in a few extra uprights between windows it definitely helps keep the whole thing more rigid.

 

Comet  

Many thanks for the reply. The 119 suggests using double sided tape, an idea I'm uncomfortable with for several reasons, so I'll be glueing as you have done.

 

I'm very heartened by your tale, as I don't like the idea of pre-painting before the job is done - it's far too easy to do something later that makes a mess.

 

Thanks again, I'm sure I'll be following your approach.

 

John.