TUTORIAL MOD 7745 to Use the PF Motor Still on 12v Track

[bricks n bolts]

Hi all, I want to share a technique I've been using to get 12v power to the new PF motor, also useful for loco lighting. My track is grey era 12v and I wanted a way to use the new motors and not be reliant on the old ones which are getting very expensive and which I have a bad habit of breaking. My layout is on a table and crashes tend to be catastrophic, breaking the pins off many a good motor By comparison the new PF motors are very cheap and if I do break some of these it's not that bad. I know over-voltage is an issue but so far I've haven't had any problems.

The trick is to modify the type 1 pickup bricks from the 1969-1975 12v motors so they are compatible with the 9v conductive plates. Note I think the type 1 is better than the later 1976-1980 type 1 & 2 due to :

1. the side of the brick the pins are - they fit the right side of a standard wheel base.

2. the thick, 100% metal pins are better for this mod

3. the pickups themselves seem to be made of better quality metal (I don't know but it's more 'brassy' looking - things were made solid in those days!).

Obviously using such an ancient brick is both the beauty and the flaw to this as they are becoming rarer and on top of that you can say I either bring them up to date or brutalise them depending on your point of view. At least I can spray Teflon lubricant at them without fear that I'll break the motor whilst doing so.

The example I'm going to show you is to convert the 7745. I've also changed all the 7745 standard wheels to 9v/PF wheels as they are so much better from a friction point of view, which matters when using PF motors, and also look good in my opinion. I like the classics but also like to apply upgrades as it keeps things alive, plus some things I never liked such as the 7740 pantographs, so was happy to swap those for a modern design.

The rough and ridged 12v track probably doesn't help that much either regarding friction and I have a feeling the the PF motor wheels spin slightly on the curves due to the ridge on the inside tracks, it's not a big issue but I'll probably replace them with ME Model curves if/when they come out. I would probably go all the way to 9v if there was a viable pickup option that didn't rely on using old 9v motors which are soon becoming as expensive as the 12v ones.

Step 1 - Convert two Type 1 pickup bricks.

Note that the base of the pins exactly match the size of a stud!!

We need to cut and sand down the metal until we no longer have the pins but instead two metal studs. It took me a while to get fast at this, first I use some heavy duty cutters followed by sanding - be very careful not to accidentally sand off the top of the plastic studs! Here is a before and after :

The bricks are now 9v conductive plate compatible!!

Step 2 - Add a 1x2 conductive plate to one of the modified pickup bricks:

Step 3 - Add a 9v/PF wheel set to the pickup brick with the 1x2 conductive plate. I did try using motor wheels but the technic axle hole meant that the pickups were about half a plate too far or too close to the track.

Step 4 - Add a 2x8 conductive plate (these only seem to come in white) on top of what we have so far :

Step 5 - Attach a 2x4 conductive plate to the 2x8

Step 6 - Add one plain non-conductive 1x2 plate :

Step 7 - Add another 9v/PF wheel set on the other side :

Step 8 - Fill in / reinforce the missing gaps in the middle with standard plate / any decorations :

Step 9 - Add a bogie plate and magnet assembly :

Step 10 - Add a 9V wire to the other side. Note a 9v plug is two plates thick, so we don't need any more conductive plates to complete the circuit to the other pickup brick.

Step 11 - Add the second pickup brick so all elements are connected and we have a complete bogie!

Now we can put it with the loco :

Here it is on the track :

Without the roof, there is a 'plug tower' consisting of the PF motor plug, 2 9v/PF conversion wire plugs, 9v bogie pickup plug and for a 9v plug for the lights (which I converted to end in 12v plugs so I can still use the 12v light bricks). I had to lose a couple of studs worth of the decorative motors, but all in all it's hardly noticeable. I did also add one more weight brick at the end to give the PF motor a bit of extra grip, which means this 7745 now has two weight bricks.

From underneath, note the distance between the pickups is exactly the same as on a grey era 12v motor.

I also gave the end buffet car carriage one pickup for the lights. You can use two pickups but one is fine for lights - I don't mind the slight flicker you get when the train crosses switch points. This avoids the old problem with the 7745, whereby you have to run a wire along the whole length of the train just to light up the end car. I got an extra carriage for it, so that would be an extra pain!

Bear in mind that you may want to skip this if you are pulling more than 4 carriages as the additional pickup on the end carriage will increase friction.

That concludes the guide, hope you found it useful! More coming soon.

I should add this train is mega-fast!! I usually avoid over-charging it on 12v by the fact that at that speed it will derail. I find that as long as I have 2 trains running it's not a problem to whack it on full, but if the other train stops for some reason I'm in trouble. Plus, as I said, if I do break the motor I can still use the pickups and just get another cheap motor from S@H, a lot easier than trawling ebay for a good deal on an original 12v motor. Although I may try opening up one motor (probably when I break my first) and swapping out the internal model with a brand new 12v one (the same one mentioned in Railbricks used on model railways) and see how that runs.

Edited May 31, 2013 by Fugazi

[Toastie]

Hi all, I want to share a technique I've been using to get 12v power to the new PF motor, also useful for loco lighting ...

The trick is to modify the type 1 pickup bricks from the 1969-1975 12v motors so they are compatible with the 9v conductive plates. Note I think the type 1 is better than the later 1976-1980 type 1 & 2 due to ...

Hi Bricks n Bolts,

this is amazing! Exactly what I was looking for. See, you can run the power from your pickup into a PF LiPo. That one works like a charm with 12DC charging voltage. The LiPo is feeding a PF receiver and that one controls a PF train motor ... and you have converted the entire 12V gray era to fully compatible PF operation.

Beautiful work!!!

Regards,

Thorsten

[legomania1993]

Great idea. I'm not too familiar with the 12volt system, but have you ever considered using clone bricks and using pieces of metal to act as the pickups? Instead of using the old 12volt parts you could create your own pickups.

[bricks n bolts]

Hi Bricks n Bolts,

this is amazing! Exactly what I was looking for. See, you can run the power from your pickup into a PF LiPo. That one works like a charm with 12DC charging voltage. The LiPo is feeding a PF receiver and that one controls a PF train motor ... and you have converted the entire 12V gray era to fully compatible PF operation.

Beautiful work!!!

Regards,

Thorsten

Thanks a lot Thorsten! It means a lot as this is my first major posting.

I do find the idea cute as it bridges every train era to find a solution - it's one for us train heads.

I don't have a PF Lipo to try charging it directly. But I know what you mean, and had considered it after reading about a similar idea using 9v pickups in Railbricks.

It's cool and would mean that the train has a UPS system and can therefore run on any type of track, however the downside would be that the 12v interrupt rails / traffic lights would stop working, the expense of the Lipo box and you now have to find space for the Lipo box+receiver in the loco.

It would be fun though, especially if you had multiple track systems (I currently only really have 12v grey, some half broken bits of blue track which I don't use and literally just a couple of bits of PF track which I just got out of curiosity). This one train would be able to cross all track systems and never need a recharge!

I did order some bridge rectifiers which would mean with a bit of soldering I could complete the circuit for a such a system if I had a Lipo.

My thought is that I can use the rectifiers for lighting up LEDs when the train is both in forward and reverse. You can get LEDs that already have the resistor built in for running directly on 12v so there's not much more you need to do with them (have used them on the new lamp posts without the rectifier as they are static). You still have to work out how to mount the LEDs on brick though, I do like the 9v light bricks as you can run those straight off the conductive plates, annoyingly though they are now also no longer produced by TLG and are becoming expensive. We should get TLG to at least keep the 9v conductive plates as they are so useful/tidy generally.

Great idea. I'm not too familiar with the 12volt system, but have you ever considered using clone bricks and using pieces of metal to act as the pickups? Instead of using the old 12volt parts you could create your own pickups.

Thanks a lot legomania

That is the major flaw in the design is that these pickups are old in themselves, although will not break as easily as a motor.

I would try to create my own if I could work out exactly how. The closet thing I can see is the guide here on converting a 9v motor to also have 12v pickups.

Here he uses 7mm rivets for the pickups, some sheathing material and some very small springs. However he doesn't provide any links or any clue on where to start for sourcing this stuff. Does anyone know where to find rivets like that?

[LEGO Train 12 Volts]

Excellent solution!

I've used a similar system to run my 7745 smoothly on the track piking-up power from three different points, and for the rear wagon to pick-up power to feed the back-lights (without wiring the middle wagon)

so let me say (again) that your arrangement is neat, brilliant and original!

Edited December 17, 2011 by LEGO Train 12 Volts

[Brickaroo]

This is absolutely fantastic.

Off to Bricklink to buy some of those pick-ups. :-D

Great work!

[bricks n bolts]

Thanks a lot guys!

LT12V I saw your similar solution with the EN tender. I noticed you removed the curved decorative side, if you did that with one of the pickups on my bogie you can get the the buffer / magnet assembly one plate lower which would make it exactly the same height as most buffers. I didn't mind too much as it's on the front and it fits just fine under the loco but it's worth a mention.

I just realised that both you LT12V and Toastie are exactly the people I need help with for my next project!!

Which is to build a BR23! I've got the pdf instructions by Thorsten but am struggling on composing a list of parts so that I can order what I'm missing, I don't suppose you have any?

Here is what's started me off, I noticed that the PF motor has two 1x4 sections of brick I could attach my modified pickups to, however the standard wheel height would make them too close to the track, the same for BBB middle drivers, the same for BBB large drivers, BUT the BBB XL drivers fit perfectly!

Here is a mockup , just to house the motor/wheels/wires/lights :

It runs fine even on even on the 12V switch tracks, as long as you don't try going backwards!

9v conductive brick does the job of joining the pickups as with the loco bogie.

[LEGO Train 12 Volts]

I just realised that both you LT12V and Toastie are exactly the people I need help with for my next project!!

Which is to build a BR23! I've got the pdf instructions by Thorsten but am struggling on composing a list of parts so that I can order what I'm missing, I don't suppose you have any?

Thanks for your kind words bricks n bolts!

The BR23 is the first beauty you MUST have to enter in the BR world

However my BR23 is quite different from the origninal project written by Toastie because I have projected a less tall cab to use a medium BBB wheel and a standard lego coupling system (as you can see in the picture below):

In any case with this link: Official Ben Beneke Brickshelf Gallery you can find the file: 98_parts_list_br23.txt ...I think is that you need!

Greetings

LT12V

NOTE

Your new pictures are totally awesome ...I mean: XL Wheels and pick-up bricks ...WOW!

Edited December 17, 2011 by LEGO Train 12 Volts

[bricks n bolts]

Thanks for your kind words bricks n bolts!

There are so many great builders out there, this forum is just amazing and it's me who is honoured by any interest

The BR23 is the first beauty you MUST have to enter in the BR world

However my BR23 is quite different from the origninal project written by Toastie because I have projected a less tall cab to use a medium BBB wheel and a standard lego coupling system

It's a real beauty, I held off on getting an EN as I would much prefer to build one of these.

Funny, I was also thinking of using the medium BBB wheel for that back section. My whole base will be different because of the motor housing anyway. Also I will use a small BBB wheel for the front, I have some old red ones from the blue era but not the (likely rarer) red ones from the grey era as Thorsten has used, they look identical from the outside but the pins are different. There is also the version by Holger Matthes which uses the small BBB wheels, so I should be within the common variance.

I love your pictures.

this link: Official Ben Beneke Brickshelf Gallery you can find the file: 98_parts_list_br23.txt ...I think is that you need!

Thank you!!, I don't know how I missed that. Now I must work out some orders.

Your new pictures are totally awesome ...I mean: XL Wheels and pick-up bricks ...WOW!

There is nothing else I can see red XL drivers would go so well with but a BR23

[1974]

Hello bricks n bolts (or anyone else who have the answer)

How well does the PF motor attach to the 7745 train base? The PF motor has a 5mm stud while the old 12V system used 7mm studs/holes

I'm asking because I've bought a 7745 (not recieved yet) and I'm planning to convert it into PF. If I have to buy new trainbases it would be a bit of a bummer

Anyway thanks to b'n'b for the good work!

And yes, I'd very much like if TLG would do a re-run of those conductive plates! And in black to boot

Cheers,

Ole

[Rail Co]

Hi bricks n bolts this is a very creative way to use a cheaper PF motor. Just if I had the 12v system

Brick-on brick n bolts!

[harnbak]

Hi all, I want to share a technique I've been using to get 12v power to the new PF motor, ...

Excellent work ranging several decades of lego trains!

[BillytheKid]

Very interesting how you made this. I love to see this in real life how this works. Keep up the good work.

[1974]

Hello bricks n bolts (or anyone else who have the answer)

How well does the PF motor attach to the 7745 train base? The PF motor has a 5mm stud while the old 12V system used 7mm studs/holes

I'm asking because I've bought a 7745 (not recieved yet) and I'm planning to convert it into PF. If I have to buy new trainbases it would be a bit of a bummer

Anyway thanks to b'n'b for the good work!

And yes, I'd very much like if TLG would do a re-run of those conductive plates! And in black to boot

Cheers,

Ole

Allright, I got my 7745! Along with a large track and transformer to boot

I've made a mistake, the pin (on the motor) is indeed 7mm but_in length_, NOT diameter! The diameter is still only 5mm as used on all motors/bogie plates from 12V until now

Sorry for the confusion b'n'bs advise/MOD is all good!

It's been 25 years since I last had a 12V setup, so I got all worried for nothing

Now awaiting my 7727 ..

[bricks n bolts]

Hi Guys,

Sorry I didn't reply sooner. For some reason I thought I would get an email notifying me of any replies, but didn't...

Thanks for the compliments harnbak, RailCo and AFOL12V

1974, the difference between 5mm and 7mm bogie pins has never been an issue to me, except if you are using a non-standard train base built from brick, in which case the old 7mm ones seem better with technic plate holes, etc..

I've now also mod'ed my 7740, where I removed the PF plugs entirely and replaced with 12v ones. Those PF plugs are so bulky and hard to fit through the old train bases.

Cheers,

BnB