Richards Workbench, Heljan 31s and JLTRT Class 40s
- Thread starter richard carr
- Start date
Dog Star
Western Thunderer
Amazing - my first thought when I saw your pikkie was "that looks like something from Kier Hardy"... now he is a WTer so we may learn more about how that finish was achieved.
richard carr
Western Thunderer
The production etches for the bogie chassis have now arrived.
So I have beenbusy making up the other 3 chassis's that I need. To help solder the bearings in place I made up some wooden jigs to help keep everything lined up. These take about 5 minutes to make using some spare wooden ply sleeper as the starting point this is version A
Then I decided to spend another 5 minutes making version B
I found the B version to be better its worth doing as the better lined up they are the easier and faster it is to file the bearing to the correct size for the axle.
I have some of these spare so if anyone wants one they are £17 each or £34 a pair plus postage.
So I have beenbusy making up the other 3 chassis's that I need. To help solder the bearings in place I made up some wooden jigs to help keep everything lined up. These take about 5 minutes to make using some spare wooden ply sleeper as the starting point this is version A
Then I decided to spend another 5 minutes making version B
I found the B version to be better its worth doing as the better lined up they are the easier and faster it is to file the bearing to the correct size for the axle.
I have some of these spare so if anyone wants one they are £17 each or £34 a pair plus postage.
daifly
Western Thunderer
That seems awfully expensive for some bits of scrap wood.
john lewsey
Western Thunderer
richard carr
Western Thunderer
Yes but think of the profits, all those Heljan diesels I'll be able to buy !!!!!!!!!!!!!!!
richard carr
Western Thunderer
Now I have got back from holiday I have done a bit more work on the 40s.
I carried on building the bogies the first thing to do was to solder up the chassis once it had been folded for a bit of extra rigidity.
I then made up the beams
Again I used some wooden jigs to help hold everything square and avoid burnt fingers.
A twin beam I then cut these in half with a piecing saw. The beams are designed to use 2.5mm OD tube with 1.5 mm ID rod required.
I then made up the attachments for the bogie to the body that come with the kit, here are the bits.
There is a finished one in the bottom right corner, I have added a piece of 2.5mm OD tube, 1.5mm rod then passes through the chassis sides and the tube t form the pivot.
Here's a pair of finished chassis's I hadded the supports for the resin bogies to each side, the front one alighns with the bottom of the slots and rear one with top.
I have also soldered the screw that connects to the body to the bogie pivot.
I carried on building the bogies the first thing to do was to solder up the chassis once it had been folded for a bit of extra rigidity.
I then made up the beams
Again I used some wooden jigs to help hold everything square and avoid burnt fingers.
A twin beam I then cut these in half with a piecing saw. The beams are designed to use 2.5mm OD tube with 1.5 mm ID rod required.
I then made up the attachments for the bogie to the body that come with the kit, here are the bits.
There is a finished one in the bottom right corner, I have added a piece of 2.5mm OD tube, 1.5mm rod then passes through the chassis sides and the tube t form the pivot.
Here's a pair of finished chassis's I hadded the supports for the resin bogies to each side, the front one alighns with the bottom of the slots and rear one with top.
I have also soldered the screw that connects to the body to the bogie pivot.
Attachments
OzzyO
Western Thunderer
Hello Richard,
in post #17 you had this photo,
Of one of your class 40 bogies going through a B6 point. Looking at the far pony wheel it looks very close to the top part of the frames. This could be a possible cause of shorts. It may be an idea to file an angle from where the vertical meets the top to the front, at the front you should only need to remove 1.5mm max. to give you all the clearance you should need.
Out of interest what axles have you allowed side play on and how much.
Looking at your bogies it appears that you are not using any form of bearings and using the pivot beams directly onto the axles. So you have six bearing points per bogie, with a loco weighing approx. 5lb if all of the weight is distributed evenly that is approx. 6.5oz. per bearing point.
Looking at the photo below, all of the weight will be transmitted to the bogie above the middle driver.
Then when you look at the two pivots that transmit the weight to the wheels they are so uneven in the spacing. It may work OK. But something tells me that you could have problems. Unless you are going to use the front rubbing plates to transmit some of the weight as well.
I think that if I were doing it (I'm not that well up on compensation) I'd have a centre beam between the two front powered axles with a Y shape at the front so that the front beam would fit between the legs.
I hope I'm wrong as it looks a nice set of frames.
OzzyO.
in post #17 you had this photo,
Of one of your class 40 bogies going through a B6 point. Looking at the far pony wheel it looks very close to the top part of the frames. This could be a possible cause of shorts. It may be an idea to file an angle from where the vertical meets the top to the front, at the front you should only need to remove 1.5mm max. to give you all the clearance you should need.
Out of interest what axles have you allowed side play on and how much.
Looking at your bogies it appears that you are not using any form of bearings and using the pivot beams directly onto the axles. So you have six bearing points per bogie, with a loco weighing approx. 5lb if all of the weight is distributed evenly that is approx. 6.5oz. per bearing point.
Looking at the photo below, all of the weight will be transmitted to the bogie above the middle driver.
Then when you look at the two pivots that transmit the weight to the wheels they are so uneven in the spacing. It may work OK. But something tells me that you could have problems. Unless you are going to use the front rubbing plates to transmit some of the weight as well.
I think that if I were doing it (I'm not that well up on compensation) I'd have a centre beam between the two front powered axles with a Y shape at the front so that the front beam would fit between the legs.
I hope I'm wrong as it looks a nice set of frames.
OzzyO.
richard carr
Western Thunderer
Ozzy
Thanks for your concerns, you may be right about the potential for a short but it will have to wait until I have one of the bogies properly powered up.
As for the compensation it works just fine, I already have 2 forties running using this system and they run lovely thats why I'm continuing to develop it with the radial truck to get even more sideplay on the leading axle. The system uses 3 point compensation as each beam has its own independent pivot, its an application of the 3 legged stool so that all the wheels remain in contact with the track at all times. Mike Sharman wrote a nice little book on how to do it for all sorts of wheel arrangements years ago.
There isn't that much sideplay on each axle about 1.5mm because the outer frames limit the amount of movement you can get, which is why I need to get so much more on leading axle, the outer frames are wider there.
Richard
Thanks for your concerns, you may be right about the potential for a short but it will have to wait until I have one of the bogies properly powered up.
As for the compensation it works just fine, I already have 2 forties running using this system and they run lovely thats why I'm continuing to develop it with the radial truck to get even more sideplay on the leading axle. The system uses 3 point compensation as each beam has its own independent pivot, its an application of the 3 legged stool so that all the wheels remain in contact with the track at all times. Mike Sharman wrote a nice little book on how to do it for all sorts of wheel arrangements years ago.
There isn't that much sideplay on each axle about 1.5mm because the outer frames limit the amount of movement you can get, which is why I need to get so much more on leading axle, the outer frames are wider there.
Richard
lancer1027
Western Thunderer
Richard, can i ask who's wheels have you used?
Rob
Rob
richard carr
Western Thunderer
Rob
They are my own wheels turned up from some cast iron bar, with mild steel axles, live on one side and tufnel insulated on the other side.
Richard
richard carr
Western Thunderer
Not particularly but it works well enough as it is.
I agree it would work better if the bogie/body pivot was in the centre of the bogie but that would require a big nut coming up in the centre of the cab ! On some locos it will not work for example on a DJH 47 the pivot point is well forward of the bogie centre and 3 point compensation does not work as no weight goes to the rear axle of the bogie, I know as I tried it.
Although I haven't got to it yet I will balance the powered bogie with some lead
Richard
OzzyO
Western Thunderer
Hello Richard,
I did write a mess. about why you should have compensated about the front wheel size, 3' in dia. rather than 3'9" and that could make a difference in the size of the beams between the two front wheels .
I'm not sure about your point about a big nut in the centre of the cab? Why?
I did write a mess. about why you should have compensated about the front wheel size, 3' in dia. rather than 3'9" and that could make a difference in the size of the beams between the two front wheels .
I'm not sure about your point about a big nut in the centre of the cab? Why?
richard carr
Western Thunderer
Ozzy
I have just had a good look and no the bogie pivot isn't that far off centre so it wouldn't come up through the cab, but it would be a real pain to move it, a lot of resin would need removing and leave the floor of the body fairly weak.
It works as it is so why change it.
Richard
I have just had a good look and no the bogie pivot isn't that far off centre so it wouldn't come up through the cab, but it would be a real pain to move it, a lot of resin would need removing and leave the floor of the body fairly weak.
It works as it is so why change it.
Richard
john lewsey
Western Thunderer
It all looks rather good to me Richard
