train magnet sizes

[Rene Rechthaler]

to support the discussion in 9448.dat
https://library.ldraw.org/parts/27031
i made some pics of my parts:
   
from top to bottom:
-long cylinder (7.5mm), long magnet (D10mmxL7mm), overall cylinder length 8mm
-short cylinder (6.5mm), long magnet (D10mmxL7mm), overall cylinder length 8mm
-short cylinder (6.5mm), short magnet (D10mmxL6mm), overall cylinder length 7mm (these are too short to connect)
-"modern" magnet (2959c01.dat) with the holder (2607.dat) (magnet size D10mmxL7mm)
Also, the rear connector is always the same (could be subfiled)

I have more train magnets but have to dig them out...
i tested them, but i guess due to the age the older ones are weaker.

[N. W. Perry]

Are there any use cases where the length of the magnet makes a functional difference? Could it be could enough that the magnet (sub)part is a simple cylinder that can be scaled on the user side?

[Willy Tschager]

Beside the magnet lenght how about the different hooks?

w.

[Orion Pobursky]

I think the first 2 cases (8mm overall length) aren't worth distinguishing.

The 3rd is debatable but since it doesn't come up up elsewhere, I'm not sure it's worth our time.

[Gerald Lasser]

The magnets come in combination with the plates 509 and 753,  I redid them when doing the coupling hooks

I do not have u9448 (BL: x547c) with me, but I do have the other two 499 vatriants (BL: x547a / x547b)

x547c is a totally different construction as it clips onto the plate

x547a/b are closed, so the plate (509/753) clips onto them

I would model the two different casing sizes/lengths of the 499.

It needs an overhaul anyway as the digital shape, especially of the rounded sides does not refelct the real part

The current setup does not match the real life

Code:

1 15 0 0 30 -1 0 0 0 1 0 0 0 -1 78329.dat

1 10 -70 0 0 0 0 -1 0 1 0 1 0 0 509.dat
1 4 -38 9 0 1 0 0 0 1 0 0 0 1 499c01.dat

1 10 70 0 0 0 0 1 0 1 0 -1 0 0 509.dat
1 1 38 9 0 -1 0 0 0 1 0 0 0 -1 499c01.dat

The current 499c01 would need a longer magnet

Top: existing parts (just needs a different magnet), bottom, elongated parts.

   

[Rene Rechthaler]

   
added the part numbers (and I forgot to mark the gap, it exists)
the difficulty is that the two existing magnets 70023 and u9044 have to fit into the same part.
both magnets should be D10mm (25LDU), but dont match that.
top and bottom variants have the same small offset from magnet to rim, the center one has a bigger distance.
(would it be ok to scale the u9044 by 1.2 in length for the center one only?)

[Magnus Forsberg]

added the part numbers (and I forgot to mark the gap, it exists)
the difficulty is that the two existing magnets 70023 and u9044 have to fit into the same part.
both magnets should be D10mm (25LDU), but dont match that.
top and bottom variants have the same small offset from magnet to rim, the center one has a bigger distance.
(would it be ok to scale the u9044 by 1.2 in length for the center one only?)

Why a longer magnet?
It must be possible to move it inside the red/blue holders.
I remember having to glue them back into the holders.

[Rene Rechthaler]

Did you measure them?
the shortest magnets are 7mm overall, there has to be a 6mm magnet inside...
the longer ones are 8mm overall -> D10x7mm magnet
the 2959c01.dat is even easier to measure -> D10x7mm magnet (part is wrong)
same for 735.dat: i have a disassembled one -> D10x7mm magnet (part is wrong) (ok could have different versions)
cant check all my variants now, some parts are too well stored
for 499.dat: the outer sleeve is D11.8xL6.5mm and can fit both D10xL6mm and D10xL7mm
has another version with 7.5mm sleeve (rest is identical), fits only the D10xL7mm

[Willy Tschager]

This is the comparison on the PT

https://library.ldraw.org/parts/27031
https://www.bricklink.com/v2/catalog/cat...ge?P=x547c

https://library.ldraw.org/parts/9826
https://www.bricklink.com/v2/catalog/cat...ge?P=x547b

https://www.bricklink.com/v2/catalog/cat...ge?P=x547a
Not in LDraw

So what are we gonna do? I also do think we should use the magnets available in our library and adjust them to the holder so that you can build the combinations shown in Rene's pic.

w.

[Rene Rechthaler]

How should we handle the wrong sizes of the official parts?
70023.dat is D24xL16, but should be D25x17.5 (D10x7mm)
u9044.dat is D26xL15, but should be D25x15 (D10x6mm)
both magnets should be able to fit into 499.dat

one more thing (if we open that package and start to rework things):
2959.dat should have flat sides at the hinge
https://www.bricklink.com/v2/catalog/cat...=73092#T=C
outer diameter 12mm (30LDU), but distance of the flat sides are only 11,7mm (~29LDU)