Parkside compensation springing.

[Hal Nail]

I am well aware i'm covering old ground here but even the mighty Google isnt throwing up the right links.

 

I'm about to build a Parkside Toad and with its longish wheelbase, I feel compelled to try some form of springing. I've often used bent paperclips under a loose axle on Parkside wagons, or nothing, or brass compensation units (not so keen on these) and a couple of Slaters wagons I bought had home made rocking axle box units which is a possibility for this kit given the W irons come separately to start with.

 

However given the long plastic springs would effectively mask anything behind them, I'm thinking of using wire springs (guitar string?) to support the usual Parkisde floating axle box units.

 

Can anyone who has tried this advise what gauge and length of wire they would recommend? And does it actually work or not worth the hassle?

 

I'll be honest i never actually run anything but its the principle

 

 

[Simond]

Ian

 

try this

 

(or a page or two earlier)

 

HNY

Simon

 

[Hal Nail]

11 hours ago, Simond said:

Ian

 

try this

 

(or a page or two earlier)

 

HNY

Simon

 

Nice! I must have missed that at the time somehow - I had remembered you trying coil springs.

I think the trusty Les Paul might be getting new strings...

Particularly pleasing given all my stuff is in storage other than basic tools and the one kit, that I can do this with what I've got to hand!

 

[Simond]

Let me (well, all of us!) know how you get on as I think there’s an argument for a simple jig to bend the springs,and I’d like to make one.  
 

I tried to keep it all in one plane as that means the same spring works in all 4 (or 6) locations, and the jig would be simpler.  I have in mind a metal plate with a horizontal stop, against which the wire is laid, and a couple of pins around which the wire can be bent,  if I get it right, the edges of the jig can provide the location for the snips to trim the wire to size.

 

I suspect the same approach would work for brass wagons too.

 

good luck!
Simon

[Hal Nail]

3 minutes ago, Simond said:

Let me (well, all of us!) know how you get on as I think there’s an argument for a simple jig to bend the springs,and I’d like to make one.  
 

I tried to keep it all in one plane as that means the same spring works in all 4 (or 6) locations, and the jig would be simpler.  I have in mind a metal plate with a horizontal stop, against which the wire is laid, and a couple of pins around which the wire can be bent,  if I get it right, the edges of the jig can provide the location for the snips to trim the wire to size.

 

I suspect the same approach would work for brass wagons too.

 

good luck!
Simon

 

Will do and belated HNY back!

 

How "stiff" should 7mm wagon actually springing be? The Peco mineral/coil underframe has the external leaf springs themselves working but its pretty hard so I've never been convinced there is enough give to actually do anything in anger.

 

Equally you dont want the thing wobbling around! Presume its a bit trial and error?

 

I'm reminded of a friends Citroen DS whose pneumatic rear suspension was playing up. Watching him driving along deadpan while it furiously bucked up and down like an elephant on an airbed was quite amusing.

 

Ian

 

 

 

 

[Miss Prism]

11 hours ago, Simond said:

Ian

try this

(or a page or two earlier)

 

Is there a specific post (or even page?).

 

[Miss Prism]

13 minutes ago, Hal Nail said:

How "stiff" should 7mm wagon actually springing be?

 

In 4mm, the empirical value of a sprung wheel deflection is usually taken as 0.5mm. It is reasonable therefore to think of approx 0.8/0.9mm deflection for 7mm scale.

[Hal Nail]

19 minutes ago, Miss Prism said:

 

Is there a specific post (or even page?).

 

Page 45, Christmas day!

[brossard]

As I think I mentioned elsewhere, I have used both Slaters and Bill Bedford systems for springing.  They both work, but IMO, I think I prefer Slaters:

 

 

The idea is to replace the plastic axleguards with brass ones as shown.  There are holes in the flange for screws or they can be glued.  The bearing carriers must be fettled to achieve a sliding fit.

 

This is a pic of the Bill Bedford product:

 

 

The model is a Parkside LNER Toad E.  You can replace the axle guards or, as I did, stick them behind.

 

The springing is acheived by steel spring wire.

 

 

I did a few wagons with springing and it is nice.  However, there is a price for the spring kits and extra work to fit them.  I have decided they are not essential for what I'm doing.

 

John

Edited December 29, 2021 by brossard

[Hal Nail]

1 hour ago, brossard said:

I did a few wagons with springing and it is nice.  However, there is a price for the spring kits and extra work to fit them.  I have decided they are not essential for what I'm doing.

My thinking was that on the GWR brake which has very wide leaf springs, it would be easy to hide a piece of steel wire behind them and then have a dropper down to the parkside floating axle box. Basically a home made Bedford!

 

Reading the chat on Western Thunder that is linked on Simon's thread, someone has basically done exactly that. Now I've seen it tho, I like Simons idea and particularly that you can set up the ride height before anything is fixed (and easily tweak it after). Plus its free if you have any old strings lying around!

[Simond]

The essential economy of it is one of the key attractions…

 

Simon

[Hal Nail]

Two types from the link Simon posted. I've used a .17 guitar string (Rotosound!). The Bedford derivative is a bit stiffer I think but there isnt a lot in it* and it was more fiddly to do. It is loose in a hole on the left with a bit of scrap sprue to stop in coming out. the right end is free to slide between two guide wires poked into holes.

 

Its a lot harder to see all this in the flesh than in the photos!

 

I liked the idea of the spring being self contained on the w iron but actually Simon's type is probably easier to adjust if set up free standing and then fixed to the floor.

 

Im going to have to think about the assembly carefully as this wagon has clasp brakes which I'll need to be able to add and I need to get the ride height right before everything is fixed.

 

*Edit - actually with a bit more testing I don't think my curved one is anywhere near stiff enough. I suspect the tighter curve Simon had used makes a difference. I still like the idea but am going to revert to the other type for now just to get this rolling. 

 

 

 

 

Edited December 30, 2021 by Hal Nail

[Hal Nail]

The other pair. The spring is a loose fit so very free to move and sits horizontal against the right hand hook in use; the little L shapes are my first safety hoops

 

Whilst I can honestly say I had a horizontal spring in mind, someone on Western Thunder had done exactly the same and after tinkering, I've ended up with pretty much the same.

 

I've been reinforcing the upwards extension of the axle box unit with offcuts of guitar string but i'm not sure if that is really needed as it's only under load in one direction.

Edited December 31, 2021 by Hal Nail

[Hal Nail]

Here is assembly method - with everything loose it is hard to test ride height.

 

On one side I've fixed the sole bar. The front part of the 2 axle box units is a tight fit so these can be pressed together and hold position in the w irons but still be taken apart. The other side were loose (my error) so I've glued the boxes together and nipped out the tie bar (on an angle to help glue them back) so the box units can drop in. I've filed a bit off the top front on the axle box so they can slide up.

 

I might have it riding a fraction low under weight but it seems to ride very smoothly with all 4 wheels on the deck on my uneven work matt. It won't absorb one wheel hitting a piece of wire etc whereas compensation does deflect - but at this point my knowledge of what to actually expect from springing is lacking!

 

 

 

 

 

 

Edited January 1, 2022 by Hal Nail