Suspension….

Simple suspension was my aim for the TOR models and I think I have achieved that. My 49 and 47 class locos have run successfully with the springy suspension I came up with a few years ago but I think my latest idea is much more successful, as the old idea did add some resistance, but I didn’t want to go to the expense of building complete new bogies so I accepted it. This new method adds springing to each individual wheel and provides improved electrical pick up without the resistance.

So I will try and explain what I have done as photos are a bit tricky.

Step 1.

Hopefully you can see here, the idea is to take a length of 8 thou phosphor bronze wire  and eventually make a “Z” shape.

Solder the wire to the inside edge of the bearing and fold as above. This is where it gets tricky because normally, you would put the axle together and drop in the bogie, but here I am going to fix the bearing in the pick up frame, without any wheels or gearing attached, which gets a little fiddly later.

 

I use some packing and a peg to hold things in place but I removed the peg in the pic so you can see. But from here I will bend the wire back along the top of the pick up frame and solder in place which creates that Z shape I was referring to earlier. Repeat for all 6 axles.

Now the failing with this is that not all wheels are equally sprung,creating issues, but it works and will make the loco run reliably. This will get us thru full exhibition weekends with reliable running.

However, discussions on rebuilding the side frame completely  has commenced.  So I would say things in the future will have a more accurate resolution. Stay tuned.

Andrew

4908 waits for 4716 from Canowindra to arrive so it can continue with its loaded wheat train to Cowra.

Wheel Exchange Part 2…

Co-Co bogies with P87 are tricky as the wheels can lock in curves which derails the leading or trailing axle. The solution to this is to allow extra lateral movement in the centre axle. We have to pack the back of the wheel to stop the Phosphor Bronze bearing from falling out of the pick up housing anyway so the solution is to pack the end axles with 20 thou Phosphor Bronze and the centre with 10 thou. Unfortunately each loco seems to be different as the centre axle isn’t always dead centre such as the 49 Class so some experimentation is required.

Clearly this pic shows the comparison in the wheels, and reminds me why I went down this path.So here you can see the packing, what you may have noticed is that the gearing is not in the centre of the axle, this makes the packing interesting as the axle will slide a little further one way then the other but isn’t a major issue.

I have had a change of plan on the suspension, so this has made things a little slower then I thought it would be but there are some benefits to the new idea.  I will do some testing this week and report back next week.

Bye for now..