Laser Cut Catenary Portals

[Titan]

On 27/12/2020 at 10:46, letterspider said:

 

The longer arm would be straightforward but I don't know the typical diameter of the pole on the prototype- it looks about 6 inches to me in photos - which would be 2mm

so that is my first question - what is the diameter on the prototype?

 

It's 4 inches.

 

On 27/12/2020 at 10:46, letterspider said:

The third question relates to the top wire of the catenary. In the photos I have seen and from what I remember, the suspension wire is usually going through a pulley - is that necessarily the case?

 

Not necessarily the case but it is common. There does have to be some means of allowing the catenary to move a little bit along track due to hot and cold causing expansion or contraction.  More recently small cantilevers like on the WCML upgrade have been favoured.  I would say inclusion or otherwise is down to personal preference.

 

 

[Dagworth]

On 27/12/2020 at 10:46, letterspider said:

 

 

So my second question -

Brass is easier to solder than steel but I am not confident the horizontal arm would have sufficient stiffness. Can I get a strong solder joint in steel? Can I solder steel to brass? To begin with I know I will need to get Carrs flux for steel.  

 

Ade

 

I make my registration arms from 22 gauge guitar string (my wires are 16 gauge guitar string). It solders easily and has a good amount of flex if needed.

 

Andi

[letterspider]

Thanks for all the replies!

[nhdesigns]

I've used the same OHLE portals you've mentioned and I have to say they are worth the price for them. Easy to assemble and modify, as I've had to do due to size limitiations on my layout. I've gone and managed to add some registration arms as well. Now I just need to prime and paint it all.