Megapoints Controller (Point Servos)

[TimberSurf]

I have been asked about components, the "off the shelf" spacers were obtained on Ebay (long lead time from China), search for "M2 Tapped Brass Stand-Off Pillar", I got 8mm, but had to add washers, so perhaps 9mm might be better. Screws are all M2 x 6mm (countersunk and pan head), the aluminium extrusion was cut from a meter length of 40mm x 10mm, available only at larger B and Q stores. As you can see from pictures, I had to pack up the height with wood, to get the right throw, but that is because my boards are only 6mm ply, should be fine on 10mm+ thick boards. Washers are needed with the mounting screws, so the holes can be oversize and allow final positioning.
Final adjustment of micro's was finicky, so although self tappers would do, the holes would need to deadly accurate. I ended up elongating/widening the holes to give the right position, but as I used nuts and bolts, hole size does not stop them being clamped in the right position.

[Dave47]

Thanks very much for the details and quick response.

[TimberSurf]

No problem, although I forget were I get things as it was quite a while ago and what I got exactly! The screws for the pillars should be shorter, probably were 4mm or 5mm long. The hardest thing to find was nuts! I bought them in 25's of washer, star, bolt (10mm) and nut kits. http://www.ebay.co.uk/itm/M2-M2-5-M3-M4 ... 35d0f84b0c, others from http://www.ebay.co.uk/itm/Hexagon-Full- ... kBhY1de73A and again http://www.ebay.co.uk/itm/M2-M2-5-M3-M3 ... js6nBerG6Q

[TimberSurf]

It is a cheap system if you have a lot of points in one area, and you don't need to switch live frogs. Looks like it might be based on an Arduino.

Megapoints now do a 4 way controller (rather than being stuck with a 12 way) and a daughter board to control frog polarity

They also now do point position indicators and block detector sensors and a communal input card to feed back to DCC.

[Tom@Crewe]

Does anyone have the problem of twitching with Megapoints?

I purchased a controller some time ago now. I have not been able to work on the railway for some time

Before I had a forced break I was having some problems with the Points controller, the problem being that the servos twitch all the time. I tried different servos. They are fitted as advised with the alloy channel.

I took each one off the layout to make sure nothing was binding, I now have them all hanging free with no control rods connected and they still all twitch some more than others.

I have the Servo Controller V1.8f, a frog controller 12 way V1.3a, feeding 4 relay module boards and using HW 15178 servo’s. All as recommended

Is there any way to stop the twitching? or is this something all Megapoint controllers do?

[TimberSurf]

I spoke with Dave briefly on Sunday.

There is an issue with servo's as they hunt to find position, usually exasperated if you set them beyond their mechanical endpoint (trying to push the point blade past its stop). But the general buzz can be seen on any servo, the answer is to switch it off after it has moved.
This is now a feature for new releases and can be incorporated by sending your boards back for a software update

"Servo pulses are automatically disabled approximately half a second after the final position has been reached. If you have a ticking or buzzing servo this should quieten it. Analogue servos will appear as though the motor has been powered off. Digital servos will continue to hold their position but in a quieter manner as digital servos regenerate the last known pulse internally (that’s what makes them digital servos)."

[Tom@Crewe]

Yes that's the problem I have. other than that is fantastic, easy to wire, full instructions, slow and accurate movement. Its only that constant twitching that spoils it and if that's cured with a update they are perfect for me.

I have sent it back just waiting for it's return now, fingers crossed.

[Tom@Crewe]

I have now received back the re-flashed board with the latest update and fitted it back on layout,
The re-flash of course came back with factory setting so I had to reset end-stops which is easy enough and expected.

I works a dream, nice slow movement, no twitching, fantastic.

[Taw Valley]

Hi guys

Sorry to bring up an old thread but it seemed rude to open up another one regarding the same product.

To operate 4 points using servos etc. Would mega points be the way to go or is there another alternative at a cheaper price?

Cheers guys

[TimberSurf]

There are a number of suppliers that do less than 12 per board, look at Peco, heathcote,dingoservo,walthers to name a few, or you could build your own from discrete components or an Arduino!