Workbench - kitbuilding a loco - PDK D40 kit

[THS92-GWR-NO]

Hi all 

 

So - in addition to my layout building I've been so curious to try kitbuilding a loco that I ordered a D40 from PDK models. 

 

Status right now: 

• Have ordered the D40 kit from PDK
• Wheels from Markits Models are on order
• And I've been looking on gears and motors from High Level

 

So, before I get all the parts - anyone got newbie tips (mainly don'ts) for someone who hasn't done more than plastic kit buildings and wagons before?

[Portchullin Tatty]

Hi Thomas,

 

I am note sure why this post has gone unanswered!  So let me offer a few pointers.

 

Firstly, an inside valve gear 4-4-0 is not a bad place to start loco building, so well done for that.  I was almost unaware of PDK kits, which is surprising given that i am rather fond of the D.40s so thanks for alerting me to them!

 

Secondly, how well can you solder?  I suggest that if you are not partly proficient, you spend a bit of time practising and also looking at other threads on soldering here.  Things like cleanliness of the metal, a good amount (but not excessive) heat, a good flux and the right solder are all important things to get to grips with.  My advice would be to use 145 degree solder throughout but to stick the white metal parts with araldite if this is your first etched kit.

 

The chief difference in building steam locos in comparison to anything else is the need to get the chassis free running.  To do this it is essential that the coupling rods exactly match each other and then exactly match the wheel base.  To do this you will need a jig.  At their simplest, these are little more than axles with turned ends - such as these available from the Scalefour Society (although there are other suppliers) at the more sophisticated end there is the Avonside Jig https://www.eileensemporium.com/materials-for-modellers/category/avonside-chassis-squared-jigs

 

 

The key thing to do is make the coupling rods as a pair, ensuring that the holes are opened out with either a drill that is perfectly vertical (ideally in a pillar drill) or a broach that you check is vertical relative to the coupling rods.  Making these as a pair is best achieved by tack soldering the two parts together with the etched holes lined as best you can (use a cocktail stick in each).  The opening up that I have described should then get to be exactly the same.

 

Once you have the coupling rods made, then mount these on the axle jigs once you have either the fixed bearings on them as well or the hornblocks if you are going for a flexible chassis.  This picture grabbed from a thread by Wenlock shows this with hornblocks:

 

 

Once you have secured the hornblock guides or bearing in place, the jigs can be released and the wheels installed - Markits are great for a beginner as they automatically quarter correctly and can be taken off and put back on a couple of times.  Open out the bearings on the axles or coupling rods very slightly (this means a few turns on the broach, not so that they are sloppy. 

 

Take your time over this and be methodical about making sure that you are keeping these distances consistent.  Chassis building is not easy, even for experienced modellers (I still get very tense when it comes to seeing if they work!) but if you have taken care and kept these distances consistent, the chassis should roll along with a finger and you should be pleased with yourself.

 

There are loads of threads on here, the Scalefour Forum and a number of books.  Iain Rice's remains a good one even if it was written prior to the creation of jigs which is why they do not get mentioned.  

 

https://www.amazon.co.uk/Locomotive-kit-Chassis-Construction-4mm/dp/1874103100/ref=asc_df_1874103100/?tag=googshopuk-21&linkCode=df0&hvadid=430901814613&hvpos=&hvnetw=g&hvrand=7896416428407628308&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006977&hvtargid=pla-301998311411&psc=1&tag=&ref=&adgrpid=97419295182&hvpone=&hvptwo=&hvadid=430901814613&hvpos=&hvnetw=g&hvrand=7896416428407628308&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006977&hvtargid=pla-301998311411

 

Good luck

 

 

[Guest Jack Benson]

On 13/12/2021 at 04:34, THS92-GWR-NO said:

Hi all 

 

So - in addition to my layout building I've been so curious to try kitbuilding a loco that I ordered a D40 from PDK models. 

 

Status right now: 

• Have ordered the D40 kit from PDK
• Wheels from Markits Models are on order
• And I've been looking on gears and motors from High Level

 

So, before I get all the parts - anyone got newbie tips (mainly don'ts) for someone who hasn't done more than plastic kit buildings and wagons before?

Hi,

All recent builds are similar to the D40, small and tight on space.
 

The drive is standard on all, HLK 13mm coreless and RoadRunner, normally the higher ratio for slow running.

 

StaySafe

[THS92-GWR-NO]

On 04/01/2022 at 15:01, Portchullin Tatty said:

Hi Thomas,

 

I am note sure why this post has gone unanswered!  So let me offer a few pointers.

 

Firstly, an inside valve gear 4-4-0 is not a bad place to start loco building, so well done for that.  I was almost unaware of PDK kits, which is surprising given that i am rather fond of the D.40s so thanks for alerting me to them!

 

Secondly, how well can you solder?  I suggest that if you are not partly proficient, you spend a bit of time practising and also looking at other threads on soldering here.  Things like cleanliness of the metal, a good amount (but not excessive) heat, a good flux and the right solder are all important things to get to grips with.  My advice would be to use 145 degree solder throughout but to stick the white metal parts with araldite if this is your first etched kit.

 

The chief difference in building steam locos in comparison to anything else is the need to get the chassis free running.  To do this it is essential that the coupling rods exactly match each other and then exactly match the wheel base.  To do this you will need a jig.  At their simplest, these are little more than axles with turned ends - such as these available from the Scalefour Society (although there are other suppliers) at the more sophisticated end there is the Avonside Jig https://www.eileensemporium.com/materials-for-modellers/category/avonside-chassis-squared-jigs

 

 

The key thing to do is make the coupling rods as a pair, ensuring that the holes are opened out with either a drill that is perfectly vertical (ideally in a pillar drill) or a broach that you check is vertical relative to the coupling rods.  Making these as a pair is best achieved by tack soldering the two parts together with the etched holes lined as best you can (use a cocktail stick in each).  The opening up that I have described should then get to be exactly the same.

 

Once you have the coupling rods made, then mount these on the axle jigs once you have either the fixed bearings on them as well or the hornblocks if you are going for a flexible chassis.  This picture grabbed from a thread by Wenlock shows this with hornblocks:

 

 

Once you have secured the hornblock guides or bearing in place, the jigs can be released and the wheels installed - Markits are great for a beginner as they automatically quarter correctly and can be taken off and put back on a couple of times.  Open out the bearings on the axles or coupling rods very slightly (this means a few turns on the broach, not so that they are sloppy. 

 

Take your time over this and be methodical about making sure that you are keeping these distances consistent.  Chassis building is not easy, even for experienced modellers (I still get very tense when it comes to seeing if they work!) but if you have taken care and kept these distances consistent, the chassis should roll along with a finger and you should be pleased with yourself.

 

There are loads of threads on here, the Scalefour Forum and a number of books.  Iain Rice's remains a good one even if it was written prior to the creation of jigs which is why they do not get mentioned.  

 

https://www.amazon.co.uk/Locomotive-kit-Chassis-Construction-4mm/dp/1874103100/ref=asc_df_1874103100/?tag=googshopuk-21&linkCode=df0&hvadid=430901814613&hvpos=&hvnetw=g&hvrand=7896416428407628308&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006977&hvtargid=pla-301998311411&psc=1&tag=&ref=&adgrpid=97419295182&hvpone=&hvptwo=&hvadid=430901814613&hvpos=&hvnetw=g&hvrand=7896416428407628308&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006977&hvtargid=pla-301998311411

 

Good luck

 

 

 

Greetings Mark! 

 

I see I've missed my notification of your reply. My appologies for that. Real life has a tendency to catch up with one. 

 

Glad to hear I could point you in their direction! 

 

Soldering I've done a bit of since starting with DCC convertion of locos, but never soldiered a kit before. With a 4-4-0 I hope the coupling rods will be ok to make. 

 

I'm sure I'll be having a lot of questions when I get started. 

 

On 05/01/2022 at 11:33, Jack Benson said:

Hi,

All recent builds are similar to the D40, small and tight on space.
 

The drive is standard on all, HLK 13mm coreless and RoadRunner, normally the higher ratio for slow running.

 

StaySafe

 

Hi Jack! 

Thanks for the pointer on drive. Going to be interesting getting the last pieces to the puzzle. 

 

Thomas,