Bachmann headcode box 24

[Porcy Mane]

On 17/01/2022 at 08:41, sulzer71 said:

This may be of interest to some of you , whilst I had a couple of these locos in many pieces I discovered that if you are willing to sacrifice the switches in the tanks and 'lop off' the support that holds them a Rail Exclusive Baby Boomer speaker (other speakers are available) removed from an SLW 24  fits very snugly in the tank facing down

 

Been there, done that.

 

I used the water tank as a second speaker housing/resonator box on the 24/1. No need to remove the switches for that conversion.

 

The fuel tank was used on my on-going 25/0 conversion. There is enough room on top of the large PCB to mount the switch circuit board if you feel the need but I just made up a shorting cap.

 

 

 

If you're happy removing some metal from the chassis block, the original speaker can be substituted with a larger version along with an improved resonator box. The upper resonator box was made from plasticard to leave enough space to fit my drive mechanism for the working fan.

 

 

Whilst I was on, I substituted the tank mounting spigots with 0.8 mm self tappers. I used genuine Knowles Sambo* speakers rather than the Chinese sourced equivalents. These are the same size as Knowles Dumbos* but have different frequency responses due to different cone materials used in manufacture.

 

 

* Unavailable from Knowles for about a decade but copies are available.

 

 

 

Massive improvement over the original sound reproduction and now on par with the SLW.

 

I suspect the sounds supplied with the Bachmann chip are by Mr Chetter with a few additional sounds, altered functionality and different horns. I would like to alter the horns but at the moment haven't found was CV's they're located on.  (Above 900?)

 

P

 

Edited April 23, 2022 by Porcy Mane
Re-upload photographs following outage.

[sulzer71]

24 minutes ago, Porcy Mane said:

 

Been there, done that.

 

I used the water tank as the speaker housing/resonator box on the 24/1. No need to remove the switches for that conversion. The fuel tank was used on my on-going 25/0 conversion. There is enough room on top of the large PCB to mount the switch circuit board if you want but I just made up a shorting cap.

 

 

If you're happy removing some metal from the chassis block, the original speaker can be substituted with a larger version along with an improved resonator box. The upper resonator box was made from plasticard to leave enough space to fit my drive mechanism for the working fan.

 

 

Whilst I was on, I substituted the tank mounting spigots with 0.8 mm self tappers. I used genuine Knowles Sambo* speakers rather than the Chinese sourced equivalents. These are the same size as Knowles Dumbos* but have different frequency responses due to different cone materials used in manufacture.

 

* Unavailable from Knowles for about a decade but copies are available.

 

 

Massive improvement over the original sound reproduction and on par with the SLW.

 

I suspect the sounds supplied with the Bachmann chip are by Mr Chetter with a few additional sounds, altered functionality and different horns. I would like to alter the horns but at the moment haven't found was CV's they're located on.  (Above 900?)

 

P

 

Excellent work @Porcy Mane , I just tried it as I had it in bits and a speaker sat on the bench  , I will refer to this when it finally comes to sound fitting mine

[Porcy Mane]

3 minutes ago, sulzer71 said:

when it finally comes to sound fitting mine

 

One thing to be aware of:

 

Due to the design of the speakers the rear of the speaker has to be completely isolated  (air tight) from the front cone side  (The bit that faces into the resonator chamber). If it isn't the speaker will pop & crackle far louder than a giant bowl of Rice Krispies.

[sulzer71]

10 minutes ago, Porcy Mane said:

 

One thing to be aware of:

 

Due to the design of the speakers the rear of the speaker has to be completely isolated  (air tight) from the front cone side  (The bit that faces into the resonator chamber). If it isn't the speaker will pop & crackle far louder than a giant bowl of Rice Krispies.

Thanks for the advice , I am actually considering getting rid of the circuit board completely with the exception of the end sections and replacing it with a Zimo ADAPLU50 board + MX645 then having the chassis top milled to possibly fit an EM1/2 to use in conjunction with a speaker in the tank 

[Porcy Mane]

24 minutes ago, sulzer71 said:

Zimo ADAPLU50 board

 

When I dump the PCB's I use the Lais adaptor boards It saves space  (and money).

 

24 minutes ago, sulzer71 said:

then having the chassis top milled to possibly fit an EM1/2 to use in conjunction with a speaker in the tank 

 

I think milling to find enough space to fit an EM1 could weaken the integrity/strength of the Bachmann chassis block.

 

For the sound improvement  (I appreciate that's a subjective thing) of an EM1 over two dumbos, for the extra work involved; I don't think  it's worth it.

 

I've filmed a comparison between the standard Bachmann speaker, my set up and an EM1. I'tll take a week or so to find the time to edit it and post it up, should any one be interested.  I find the two Sambos give much improved clarity and fidelity over the EM1. Although the EM1 gives more bass, the sound reproduction is softer and less well defined. 

 

P

Edited January 17, 2022 by Porcy Mane

[sulzer71]

Just now, Porcy Mane said:

 

When I dump the PCB's I use the Lais adaptor boards It saves space  (and money).

 

 

I think milling to find enough space to fit an EM1 could weaken the integrity/strength of the chassis block.

 

For the sound improvement  (I appreciate that's a subjective thing) of an EM1 over two dumbos, for the extra work involved; I don't think  it's worth it.

 

I've filmed a comparison between the standard Bachmann speaker, my set up and an EM1. I'tll take a week or so to find the time to edit it and post it up, should any one be interested.  I find the two Sambos give much improved clarity and fidelity over the EM1. Although the EM1 gives more bass, the sound reproduction is softer and less well defined. 

 

P

I happen to have a bunch of ADAPLU50's so that's the reasoning behind using those , they were bought as I intend to fit them to all my Heljan 26s/27s , I'm not sure milling the chassis would weaken it too much tbh as there looks to be a bit of clearance with the circuit board removed anyway so the milling would be very minimal , I would certainly be interested in seeing a video of comparisons , could you a comparison with the Suttons too? I've just been looking for the Knowles speakers but can't find many places in the UK that have stock , where do you get yours if you don't mind asking? Cheers 

[sulzer71]

@Porcy Mane ignore the part about the speakers , just realised you noted neither are available 

[Porcy Mane]

18 minutes ago, sulzer71 said:

where do you get yours if you don't mind asking? Cheers 

 

When Knowles was ceasing production I bought the last 40 Sambos and 10 Dumbos direct. I think they were old stock. I've pulled some out of very old Ipads.

I sometimes wonder if they are the same as that still available from China and probably made in the same factory? I doubt there is a large difference in sound reproduction???

[pauliebanger]

There are several different manufacturers of these drivers, all with 18mm x 13mm form factor, but quality of sound output varies quite a lot.

 

Philip Sutton undertook a lot of 'blind' testing of various manufacturers' offerings when the company who supplied Knowles announced that they were ceasing production. The type eventually selected was head and sholders above the rest.

 

Don't ask me where SLW finally sourced their drivers - it was a blind testing!

 

Best regards,

 

Paul

[sulzer71]

25 minutes ago, Porcy Mane said:

 

When Knowles was ceasing production I bought the last 40 Sambos and 10 Dumbos direct. I think they were old stock. I've pulled some out of very old Ipads.

I sometimes wonder if they are the same as that still available from China and probably made in the same factory? I doubt there is a large difference in sound reproduction???

I'm just searching for alternatives , it appears they are around 13x18x4.5 would you say?

[Porcy Mane]

21 minutes ago, sulzer71 said:

I'm just searching for alternatives , it appears they are around 13x18x4.5 would you say?

 

Dimensions are here:

 

KnowlesDumbo2403-260-00057.pdf

 

KnowlesSamboWaterProof2403-260-00133.pdf

[sulzer71]

This is all @'CHARDs fault lol (from an old thread)

[w124bob]

Since the pictures of my original 25/0 conversion are not appearing here's some new ones along with a second conversion. The two chosen were both Holbeck locos 5168 uses the chassis from 24035 with all the lighting circuit boards swapped over. 5172 is a renumber of my first conversion first shown some pages ago, I made a rookie error as I didn't check the picture I was using and numbered it 5170. Only to have it pointed out that 5170 had a replacement cl 25 style headcode box at one end!

 

[meatloaf]

Ive managed to mangel the pickups on mine whilst refitting the body screws on one bogie. Can anyone tell me how to remove the base keeper plate so i can get to the pickups?

 

Ive tested each wheel and the pickups that arent working are working and which arent. X works - 0 dosent. Runs but obviously stalls on every point.

 

 

X - X     X - X

X - 0     0 - 0

 

So on one side theres only one working out the 4. 

 

Any ideas beefore i take to my local shop to try and fix

[Porcy Mane]

29 minutes ago, meatloaf said:

Any ideas beefore i take to my local shop to try and fix

 

Unless somone has found a simpler way;

 

I found it was body off, disconnect the JST's, remove pcb and pop off the bogie tower retainer to allow the bogie to drop away.

First you need to remove the two screws below the bogie that partly retain the cosmetic outer frame, then you need to get at the top of the bogie to lever the bogie clips at the front and rear ends over and away from the bottom of the metal gear tower. You might be able to straighten the pick ups without removing the Cosmetic part of the bogie.

 

See here:

 

 

SLW at top, Bachmann at bottom here showing  access to the pick ups without removing the cosmetic bits.

 

[andyman7]

On 27/05/2020 at 19:24, GRUNFOS said:

Thanks to the Boys at Barwell I received a detail pack for the model I mentioned earlier, got it finished now. Thanks chaps.

 

 

Having researched the possible alternative numbers for 24 137 as supplied by Bachmann, the only one I could find that worked (i.e. retaining both Class 24 type headcode boxes into TOPS blue, doors not welded up; no tablet catcher/Lucas headlamps; external gauges fitted to both tanks) was 24146 - and even that had smooth sided rather than stepped bogie sandboxes. 24 141 appears to have gone to the grave with only one external tank gauge and a stepped sandbox at one end. 24s are a minefield!

[MikeParkin65]

Just to flag up that all liveries (except perhaps RTC) are currently listed in the Bargains section of the Kernow website - £190 for sound fitted seems a particular bargain. I'd get another myself but just bought the last sound fitted D5135 from the Class 37 Preservation Ebay page for £5 less 😎

[Covkid]

On 13/07/2023 at 13:16, MikeParkin65 said:

Just to flag up that all liveries (except perhaps RTC) are currently listed in the Bargains section of the Kernow website - £190 for sound fitted seems a particular bargain. I'd get another myself but just bought the last sound fitted D5135 from the Class 37 Preservation Ebay page for £5 less 😎

 

In addition to this Mike there is a very appealing offer from Kernow listed as K9919

Bachmann 32-416  blue "skinhead" 24035 and three Accurascale HUO pack T hoppers in TOPS grey.

 

£189.99  

 

Seems like a bargain to me, particularly for the LMR modellers 

[Covkid]

On 13/07/2023 at 13:16, MikeParkin65 said:

Just to flag up that all liveries (except perhaps RTC) are currently listed in the Bargains section of the Kernow website - £190 for sound fitted seems a particular bargain. I'd get another myself but just bought the last sound fitted D5135 from the Class 37 Preservation Ebay page for £5 less 😎

 

On 14/07/2023 at 17:31, Covkid said:

In addition to this Mike there is a very appealing offer from Kernow listed as K9919

Bachmann 32-416  blue "skinhead" 24035 and three Accurascale HUO pack T hoppers in TOPS grey.

 

£189.99  

 

Seems like a bargain to me, particularly for the LMR modellers 

 

I succumbed !!!

Excellent value from KMRC (no connection other than as a satisfied customer)

 

Just as a footnote - 24035 is not fitted with a boiler water tank, which I would ideally like to modify mine into blue 5026 with number and arrers on all four corners.  In the process of sawing up their 24s, does anyone have a spare tank they no longer need, or are they avaialble from Bachmann spares maybe ?

 

Thanks in (maybe hopeless) anticipation !!! 

 

Edited August 1, 2023 by Covkid
Additional content

[sulzer71]

2 hours ago, Covkid said:

 

 

I succumbed !!!

Excellent value from KMRC (no connection other than as a satisfied customer)

 

Just as a footnote - 24035 is not fitted with a boiler water tank, which I would ideally like to modify mine into blue 5026 with number and arrers on all four corners.  In the process of sawing up their 24s, does anyone have a spare tank they no longer need, or are they avaialble from Bachmann spares maybe ?

 

Thanks in (maybe hopeless) anticipation !!! 

 

Bachmann have a complete underframe https://Bachmann-spares.co.uk/product/category/710/class-24-2020-blueunderframe-yellowbeam-roundbuffer-blackshanks-32-442/e3244-210-02 , works out pricey though with the postage but let me check when I get home this evening , I may have a spare water tank

[Covkid]

17 minutes ago, sulzer71 said:

Bachmann have a complete underframe https://Bachmann-spares.co.uk/product/category/710/class-24-2020-blueunderframe-yellowbeam-roundbuffer-blackshanks-32-442/e3244-210-02 , works out pricey though with the postage but let me check when I get home this evening , I may have a spare water tank

If you do, please PM me.  Thanks.   

[sulzer71]

7 minutes ago, Covkid said:

If you do, please PM me.  Thanks.   

Will do

[sulzer71]

20 hours ago, Covkid said:

If you do, please PM me.  Thanks.   

@Covkid , apologies , didn't get chance to check last night but will make sure I do tonight , I'm 99% sure I have one as I have stripped several of them in the past