Jump to content
 

Scorpio 7mm 51XX by PAD


PAD

Recommended Posts

Now that the  JLTRT 57XX is  all but  finished awaiting  the  arrival of  the  etched plates from Guilplates, I have  managed to make  a start on the  Scorpio 51XX.

 

Unlike the  57XX, it  is  packed  in a nice sturdy box suitable for storing the completed model (albeit  with added padding).

post-13414-0-87757900-1454922626_thumb.jpg

 

And here'what's inside.  The Slaters wheels were sourced from Scorpio with the kit. I'll be getting  a suitable  ABC motor gearbox unit  later.

post-13414-0-90121400-1454922625_thumb.jpg

 

The  cab rear and  the  front drop plate are now in nickel silver instead of brass and  hence the  gaps in the  brass etches. Perhaps an original error in the  etchings  has  been corrected??

Here's the  castings laid out. Overall they look quite good, although any that don't  fettle  up well will be  replaced if  better items  are available.

post-13414-0-06555300-1454922702_thumb.jpg

 

Here's where I have  got  to so far. Most of  the  rivets on this  kit  need punching out which I don't  mind but  there's about  400 just in the  frames!

 

post-13414-0-05723700-1454922628_thumb.jpg

 

The frames need a slight  alteration which is  mentioned in the  instructions  which are  very comprehensive,

 

And the  frames, spacers and  compensation beams ready for  soldering.

 

post-13414-0-16121700-1454922633_thumb.jpg

 

Cheers,

Peter

 

Link to post
Share on other sites

I followed the build of your 57XX with great interest, excellent work, and so nicely reported. 

 

The 51XX can build into a good model, Brack's has a really nice example, that he built a couple of years ago. There are challenges with the boiler length,and height, front weather board position and cylinder widths, nothing that can't be amended with the parts supplied however, you could graft in the 56XX boiler from JLTRT as they are the same GWR standard 2.  I would advise the use of the drawings in Great Western Journal no 5, as a guide, these are reproduced there in 7mm scale thanks to Tony Reynalds, if memory serves me correctly, and would serve dividends no doubt.

 

I will follow this with the utmost interest and best regards,

 

John

Link to post
Share on other sites

Hi John,

Thanks for the kind words on the 57XX. One thing I overlooked was the route indicator disc and power class letter. Should have put that on before the weathering but will have to do it later. The GWR is a little outside my comfort zone and these livery details completely passed me by till now.

 

Thanks also for the heads up on the boiler issues and the drawing in the GWJ . I have a copy of that as part of the research and will check out the boiler parts. By front weather board do you mean the cab front plate? What is the problem with that?

 

Just an additional comment on the instructions. As I said they are very comprehensive with a mix of diagrams and text. Two or three areas where slight ammendments to the etchings are needed are also noted. Here's one of the two chassis diagrams.

post-13414-0-06672800-1454965754_thumb.jpg

 

The only negative aspect is the photo copies of the etches. The various parts are all numbered clearly to match up to the references in the text, including an additional number identifying how many of the parts there are, where there are more than one. That's all fine but the quality of the photo copied images of the frets is very poor making them difficult to see easily. To make things easier I have printed the photos I took of the frets and added the numbers to these. Much easier to follow. This is the photo copy from the instructions of the chassis fret. Not good!

Cheers, Peter.

 

post-13414-0-52431900-1454966181_thumb.jpg

Link to post
Share on other sites

Hi Peter,

 

The Front Weatherboard is the traditional GWR title for the cab front plate as we would call it, the GWR loved it's titles, the drawings of the frames are called the Erecting Plan and the GA the Frame Plan, all makes sense.......!? honest.

 

If you build the boiler as etched,the cast shoulder of the Belpaire moves the cab front back to far, by about 3mm, so check the boiler assembly against your drawing, shorten as required, both in height and length this will allow you to move the cab front forward to the correct position.

 

I will talk with Dave Murdoch if I see him on Friday, as he completed his last year. Hopefully I will see Alan (Brack's) in about 2 weeks and discuss his build and the issues he had and how he resolved them, for his is outstanding.

 

Pity you can't get down the Hardwicke (GlosGOG) April 3rd.

 

It will all sort itself out I am sure, we'll enjoy the journey with you

 

John.

Link to post
Share on other sites

After a decent session at the bench I now have a rolling chassis. I have assembled the parts as per the instructions with one small modification. It is suggested that the turned brass pivot for the compensation beam is added from the inside and soldered to the outside of the frames. Don't like that for two reasons. First it then needs to be trimmed, filed back and cleaned up. Second after all that there is very little contact between the pivot and the frames. Seems to me at some point in the future this could pop out. Therefore I soldering it from the outside where there is better contact with the flange on the pivot. The beam does not need to be fixed to the pivot as is is held in place by the axle bearings. Here's the frames showing the inside and outside views. Sorry about the poor image quality.

post-13414-0-63320600-1455131511_thumb.jpg

 

And here's the frames assembled.

 

post-13414-0-99552100-1455133006_thumb.jpg

 

The rear truck is just a simple pony truck not a radial truck as on the prototype. As long as it looks the part when finished and functions ok I can live with that. It's a bit flimsy so I'll beaf it up a bit later to make it more robust. Also got the front pony truck done as well and fitted all the wheels. All is square and everything runs so far. I will also add some side control to the trucks later.

post-13414-0-89861600-1455133380_thumb.jpg

post-13414-0-77186400-1455133407_thumb.jpg

Cheers, Peter

Link to post
Share on other sites

Looks good, It's a shame it was not designedwith the radial rear axle I am sure it would be as easier to draw than the changes needed to make it a pony truck.

Not sure about that, as the pony truck is a very simple one piece etch.

post-13414-0-60051700-1455138454.jpg

As long as it works OK I don't mind either way. What I don't like are the coupling rods which are designed to pivot on the centre crank pin not at the joint behind it, as on the prototype. In 7 mm that's not acceptible to me and I'll be modifying them to pivot at the joint. Don't know if all the Scorpio kits are like this, but the Seven Duke was, so I assume the Brittania is as well. I have an Acorn rebuilt Merchant Navy that has this set-up and I have found that as there are three separate etches running on the crankpin bush, they wear grooves in it. Much better to have the three soldered as one thick boss to spread the contact evenly along the bush. Cheers, Peter

Link to post
Share on other sites

Hi PAD, been tempted by one of these kits for a while...

 

I'm a GE modeller usually, but I'm also a fireman on the Epping Ongar Railway, and spent more time on our 41xx than any other engine, and quite fancy a model of one.

 

If you need to know any details, just ask as I know the engine pretty well..

 

JB.

Link to post
Share on other sites

Hi PAD, been tempted by one of these kits for a while...

I'm a GE modeller usually, but I'm also a fireman on the Epping Ongar Railway, and spent more time on our 41xx than any other engine, and quite fancy a model of one.

If you need to know any details, just ask as I know the engine pretty well..

JB.

Hi JB, many thanks. I will take you up on that if I get stuck. I took over 200 photos of the pair at Didcot so hopefully I have enough info. However, if you see anything that does not look right, don't worry about being critical, just give me shout.

Cheers, Peter

Link to post
Share on other sites

Made a start on correcting the coupling rods, and also did some work on the cylinders and slide bar brackets.

Here's the  coupling rod laminates before  soldering.  As can be  seen they are designed to pivot on the  center crank pin, not at the  joint behind it  as  on the  prototype.

post-13414-0-90869200-1455381691_thumb.jpg

 

First thing is  to line them up in some  way to solder them at the  middle crank pin boss. Again the  Avonside  jig  is a big help, but is not  essential.  

 

post-13414-0-49886200-1455381693_thumb.jpg

 

After soldering the  front section and  the  middle  boss, you  then have  a rigid coupling rod, but  without the the rear laminates added yet.

post-13414-0-81679800-1455381695_thumb.jpg

 

Then the  rear rod is cut free at the  joint and  the  center of  the  joint drilled through on the  out laminate. I then replaced them in the  jig with the  rear laminate also in place  and drilled all the  way through.  The  rear section can then be tack soldered away from the  joint to keep the  laminates in line, and  then both sections can be taken out and  put  in the  vice to solder all round.

post-13414-0-74544900-1455381697_thumb.jpg

 

After that both rods were cleaned up and  pinned at the  joint with some nickel silver rod.  After trimming and  cleaning up this  is  what you  have.

post-13414-0-83406400-1455381699_thumb.jpg 

 

A nice touch which you  don't always see, is  the  "cork" represented on the  middle laminate.  Much better than having  to drill the  oil pot later and solder in some  wire for  the  cork.

 

Here's the slide bar bracket parts.

post-13414-0-35262600-1455382957_thumb.jpg

 

And after soldering.

post-13414-0-96428800-1455382958_thumb.jpg

 

In the  vice for  cleaning up.

post-13414-0-83273800-1455382960_thumb.jpg

 

And finished

post-13414-0-58503300-1455382962_thumb.jpg

 

I put a good fillet of  solder behind the  fold to strengthen it  up.  No need to clean up as it  won't be  visible.

post-13414-0-57160200-1455382964_thumb.jpg

 

Moving on to the  cylinders. Got  the  wrappers in place and placed in the  frames along with the slide bar brackets. When the  slide bars are  in place this  will make  a nice rigid removable  unit.

post-13414-0-06589400-1455383270_thumb.jpg

 

On to the  cylinder castings. Here's the  parts after some  fettling, but  not complete.   The  slide bars on the  right had  only received a quick whiz with the  wire brush in the  mini drill.

post-13414-0-72410800-1455383565_thumb.jpg

 

After some thought I decided to epoxy the  cylinder plates rather than solder in place.  These are meaty castings and soak up a  lot of  heat so it is  difficult to get  away with the  minimum mount  of  solder, which means a  lot  of  cleaning up afterwards. Excess epoxy is  much easier to remove and also givse  you  a few minutes to ensure that everything is  lined up before it cures.  The  slide bars were soldered in place however. (horses for  courses!)

post-13414-0-41069000-1455384010_thumb.jpg

post-13414-0-57805100-1455384104.jpg

post-13414-0-66396600-1455384012_thumb.jpg

post-13414-0-72074000-1455384144_thumb.jpg

post-13414-0-85011900-1455384145_thumb.jpg

 

And the  cross heads with the lubrication hole drilled. I Think it  is  to access a cork in the  small end of  the  correcting rod.  Perhaps Scale7JB could comment on that?

post-13414-0-53532400-1455384308_thumb.jpg

 

The clearance behind the  cross head will be  very tight when the  coupling rod is  in place, so the clearance on the  front wheels had  been kept  to a minimum. I did this by moving out  the  top hat bearings having centered the  wheels (with Costa Coffee stirrers), rather  than having  to add washers.

post-13414-0-97527300-1455384745_thumb.jpg

post-13414-0-73610500-1455384822_thumb.jpg

 

I'm really pleased with how  it's going so far. The castings need a little more work than some more  expensive kits, but  they look the  part when fettled. I now  have to correct the left hand coupling rods and  get the  other  set  of  slide bars fettled and  fitted.  At the  moment the  chassis is  quite  flexible and I will be  making additional spacers at some point to make it  more rigid.  Need to get  the  motor gear box from ABC before doing that though.   Soldering  the slide bar bracket in place  would help but  I won't  be  doing  that as mentioned above. I'll put  a spacer underneath with a captive nut and screw the  bracket cross plate with a  counter sunk screw.

 

Cheers,

Peter

 

 

 

 

Link to post
Share on other sites

Absolutely mate, finger hole for the corks.. You could possibly open it up Ever such a little bit, but I don't know any dimensions off hand..

 

Our 41 is a bit weird, as it has different designs of connecting rods either side, one has a cork in the top of the boss, and the other has a cork projecting at 60 degrees so can be filled from aft the crosshead.

 

So much got Western standardisation..

 

JB.

Link to post
Share on other sites

 

A nice touch which you don't always see, is the "cork" represented on the middle laminate. Much better than having to drill the oil pot later and solder in some wire for the cork.

 

Don't often see as it somehow gets filed off ahem redface2.gif
Link to post
Share on other sites

Absolutely mate, finger hole for the corks.. You could possibly open it up Ever such a little bit, but I don't know any dimensions off hand..

JB.

Thanks JB. However, looking at this shot of a large prairie cross head, I think I'll leave it as it is. I found this on here the other night but don't recall who thread it was, so thanks to whoever posted it.

Cheers, Peter.

post-13414-0-44648100-1455397637_thumb.jpg

Link to post
Share on other sites

 There seems to be plenty of space behind the slidebars.

 

Hi N15class, there does now, but I hope there will still be clearance when rods are on. Jazz built one back in 2012 and wrote:-

"The big problen was absolutely no room for the crossheads to clear the coupling rods."

However, we shall see.

Cheers, Peter

Link to post
Share on other sites

There seems to be plenty of space behind the slidebars.

Hi N15class, there does now, but I hope there will still be clearance when rods are on. Jazz built one back in 2012 and wrote:-

"The big problen was absolutely no room for the crossheads to clear the coupling rods."

However, we shall see.

Cheers, Peter

 

By the time the rods and the cross heads are in place there won't be much room at all, on my 42xx I had to pack the front axle out until there was no side play at all..

 

ATB,

 

Martyn.

Link to post
Share on other sites

Made a start on correcting the coupling rods, and also did some work on the cylinders and slide bar brackets.

Here's the  coupling rod laminates before  soldering.  As can be  seen they are designed to pivot on the  center crank pin, not at the  joint behind it  as  on the  prototype.

attachicon.gif20160211_120900-1.jpg

 

First thing is  to line them up in some  way to solder them at the  middle crank pin boss. Again the  Avonside  jig  is a big help, but is not  essential.  

 

attachicon.gif20160211_123520.jpg

 

After soldering the  front section and  the  middle  boss, you  then have  a rigid coupling rod, but  without the the rear laminates added yet.

attachicon.gif20160211_125002-1.jpg

 

Then the  rear rod is cut free at the  joint and  the  center of  the  joint drilled through on the  out laminate. I then replaced them in the  jig with the  rear laminate also in place  and drilled all the  way through.  The  rear section can then be tack soldered away from the  joint to keep the  laminates in line, and  then both sections can be taken out and  put  in the  vice to solder all round.

attachicon.gif20160211_131914.jpg

 

After that both rods were cleaned up and  pinned at the  joint with some nickel silver rod.  After trimming and  cleaning up this  is  what you  have.

attachicon.gif20160211_152839-1.jpg

 

A nice touch which you  don't always see, is  the  "cork" represented on the  middle laminate.  Much better than having  to drill the  oil pot later and solder in some  wire for  the  cork....

 

Crankpin-jointed rods are common in 4mm scale, and not necessarily easy to correct either.

Link to post
Share on other sites

I'm on a business trip but brought my bag of tricks with me so I could do a bit of fettling in the hotel. Wanted to get the other coupling rod modified and laminated so had to improvise as I don't have the Avonside jig with me. Here's what I did.

post-13414-0-58735100-1455669117_thumb.jpgpost-13414-0-23465300-1455669149_thumb.jpg

It's the same sequence of events as with the other rod but using a piece of wood drilled to take steel pins from the Avonside to line things up.

post-13414-0-36446400-1455669240_thumb.jpg

 

Worked a treat. The jig is nice but not essential and it could be done with any suitable size rod or tub to go through the crank pin holes into a piece of wood.

post-13414-0-27784700-1455669459_thumb.jpgpost-13414-0-11529400-1455669478_thumb.jpg

 

I have also got the slide bars and bracket fixed to the cylinders.

 

 

post-13414-0-95120300-1455669801_thumb.jpgpost-13414-0-86018600-1455669821_thumb.jpgpost-13414-0-04533300-1455669849_thumb.jpg

Cheers,

Peter

Link to post
Share on other sites

Archived

This topic is now archived and is closed to further replies.


×
×
  • Create New...