dave flint Posted October 17, 2011 Share Posted October 17, 2011 With a morning at home and the wife out at work, I thought it would be opportune to test and chip my latest purchase - a G2 with the small cab, Bachmann 37-478 with the LMS tender. The decoder fits in the tender, and it easily opens (remove two screw at the back of the tender, although brake rodding gets in the way), Drop Bachmanns own 21 pin chip in..... test it (works fine), but then the bopdy won't fit on...... The chip protrudes too far forward, stopping the body going back on ! To accomodate a speaker - used by a minority IMHO - they've spoiled it for most users, by putting the pcb right at the front of the tender, and running out of room for their own chip ! It looks like I should be able to unscrew the one screw holding the PCB and chip in this position, but having done this, my pcb won't budge, and by pulling it I'm getting lots of creaking and groaning from the pcb and tender. So, do I take it back, or does someone do a 21 pin decoder that's smaller or orientated differently ? Nice one Bachmann. Sorry - rant over, but really cheesed off !! And apologies for the poor pictures. I'm using a crappy loan phone whilst the smartphone is in works. Link to post Share on other sites More sharing options...
neal Posted October 17, 2011 Share Posted October 17, 2011 It could be me, but I fear that the decoder should be the other way around? See: http://www.Bachmann....pdfs/G2A_01.pdf I have two of the original batch both with Bachmann decoders, and I didn't have any problems, seems odd if the tender design has changed for later models. Perhaps the pcb is 180 degrees out? N Link to post Share on other sites More sharing options...
gordon s Posted October 17, 2011 Share Posted October 17, 2011 You are correct Neal. From memory, the decoder has a feed through socket and Dave has put it on upside down. Simply turn it over and it will fit inside the tender no problem. Funny how we are quick to blame every one else when things don't go to plan..... Link to post Share on other sites More sharing options...
andyrush Posted October 17, 2011 Share Posted October 17, 2011 You are correct Neal. From memory, the decoder has a feed through socket and Dave has put it on upside down. Simply turn it over and it will fit inside the tender no problem. Funny how we are quick to blame every one else when things don't go to plan..... If it is anything like the one I had, turning the chip over is not the answer. The problem is due to excess solder blocking one of the pin sockets. Mine went back to the vendor and was fixed. Still cost me the postage, though Link to post Share on other sites More sharing options...
dave flint Posted October 17, 2011 Author Share Posted October 17, 2011 "Simply turn it over and it will fit inside the tender no problem. Funny how we are quick to blame every one else when things don't go to plan..." Really ? With the chip installed as shown, the loco goes in the right direction, but it doesn't have lighting to test on it. The missing pin is correclty located in the bottom LH corner (see my top picture). If I turn it over, then the pins won't orient properly. I'm prepared to accept that the PCB is out by 180 degrees, as the blanking chip pointed forward too (on the Bachmann service sheet it points backwards.....), but it is much shorter than the chip, and fitted in the tender without problems. Remember, the PCB won't budge - at least not with the force I'm prepared to exert on it. The chip itself went into the NRM DELTIC without fuss as a trial, and went in excalty the same way as this one........lights and direction working normally there. Link to post Share on other sites More sharing options...
34theletterbetweenB&D Posted October 17, 2011 Share Posted October 17, 2011 Assembly error, the socket has been installed wrong way round in the tender. If the designer had employed poka yoke technique so that there was only one way around the socket could be installed, then the assembly operative could not make the mistake. Definitely return as 'unfit for purpose'. Link to post Share on other sites More sharing options...
gordon s Posted October 17, 2011 Share Posted October 17, 2011 OK, fair enough, as I said I was endeavouring to help you from memory and years of experience in pcb connectors. From your description, it could have only been the board or the chip were the wrong way round. An assembly error or a QA issue, but not 'design stupidity' by any means. I'm sure you will get it sorted without problem.... Link to post Share on other sites More sharing options...
deltic56 Posted October 17, 2011 Share Posted October 17, 2011 "Definitely return as 'unfit for purpose'. " A bit strong I feel one inncorrect example out of hundreds sold it does not warrant this type of rant. Common sense should be employed Link to post Share on other sites More sharing options...
34theletterbetweenB&D Posted October 17, 2011 Share Posted October 17, 2011 That's not a rant, that's the correct and logical thing to do. Unless the manufacturer is made aware that assembly errors are occurring, there can be no systematic correction. There are good proven techniques in design to prevent this kind of assembly error, and learning how to drive out error at every stage is always the way forward for lowest cost in the complete process. I'll take my eight-sigma hat off now... Link to post Share on other sites More sharing options...
deltic56 Posted October 17, 2011 Share Posted October 17, 2011 One inncorrect example out of hundreds is the IMPORTANT part of the post. You can have all the production checks in the world and still one will slip through. Perhaps in Hatfield things are different?? Link to post Share on other sites More sharing options...
RMweb Gold RedgateModels Posted October 17, 2011 RMweb Gold Share Posted October 17, 2011 Steady on chaps, we seem to be heading down the road to thread lockingness There are good proven techniques in design to prevent this kind of assembly error The above quote suggests that Bachmann could have designed the PCB in a way that it could not have been fitted incorrectly - thus eliminating any error, however infrequent. The original OP was a tad, lets say, tactless in it's title, lets not continue in this vein. Link to post Share on other sites More sharing options...
Andy Y Posted October 17, 2011 Share Posted October 17, 2011 Steady on chaps, we seem to be heading down the road to thread lockingness It was quite close to that with the original topic title. Link to post Share on other sites More sharing options...
RMweb Gold mcowgill Posted October 17, 2011 RMweb Gold Share Posted October 17, 2011 An assembly error or a QA issue, but not 'design stupidity' by any means. I would disagree, we use poka yoke techniques in design here and it makes a world of difference to problems caused by incorrect manufacture/assembly. For those who don't understand the term, the idea is to design something such that it is impossible to assemble it incorrectly, different shaped and sized dowels/spigots/holes etc that mean that if the board is turned upside down or the wrong way round it's not possible to fit it. It doesn't add anything to the cost of the model if it's introduced at the design stage. If you don't design out potential assembly errors like these, the guy at the bench assembling them WILL manage to put them in wrong some or even all of the time. Martin Link to post Share on other sites More sharing options...
34theletterbetweenB&D Posted October 17, 2011 Share Posted October 17, 2011 One incorrect example out of hundreds is the IMPORTANT part of the post. You can have all the production checks in the world and still one will slip through... As Martin has explained, the poka yoke principle is to make it impossible for the assembly operation to go wrong. The correct build quality is designed in, rather than assembly errors inspected out. The standard aimed at is not 'only one in a few hundred' but defect rates pushed toward one per billion. Anyone seriously interested should read 'Toyata Production System', or 'Canon Production System' for an insight into what may be achieved. I might note at this point that one of the leading figures in pushing this quality revolution, Dr Joseph M Juran, lectured the American Association of Motor Manufacturers in 1962, telling them that the Japanese motor industry would tear them apart. They laughed then... Link to post Share on other sites More sharing options...
RMweb Gold Oldddudders Posted October 17, 2011 RMweb Gold Share Posted October 17, 2011 Can anyone suggest why a British steam loco needs a 21-pin socket and hence decoder? If 6-pin is ok for Kernow's 0298, then it is also good enough for any other steam loco that doesn't have lights/sound/smoke, presumably. I have been convinced there may be a need for diesel and electric locos with multiple light options, but steam? Link to post Share on other sites More sharing options...
RMweb Premium spamcan61 Posted October 17, 2011 RMweb Premium Share Posted October 17, 2011 If the designer had employed poka yoke technique so that there was only one way around the socket could be installed, then the assembly operative could not make the mistake. There do seem to be many missed opportunties by the designers for proper design for manufacture, maybe it's not considered cost effective given the volumes involved: the VEP bogie orientation and the random engine tender polarity on the MN(?) come to mind. Link to post Share on other sites More sharing options...
RMweb Premium spamcan61 Posted October 17, 2011 RMweb Premium Share Posted October 17, 2011 Can anyone suggest why a British steam loco needs a 21-pin socket and hence decoder? If 6-pin is ok for Kernow's 0298, then it is also good enough for any other steam loco that doesn't have lights/sound/smoke, presumably. I have been convinced there may be a need for diesel and electric locos with multiple light options, but steam? My guess is that they want a one size fits all decoder socket, so that a sound chip can be easily added for example: I wouldn't be surprised if the 8 pin socket slowly dies out. Link to post Share on other sites More sharing options...
frobisher Posted October 17, 2011 Share Posted October 17, 2011 Can anyone suggest why a British steam loco needs a 21-pin socket and hence decoder? If 6-pin is ok for Kernow's 0298, then it is also good enough for any other steam loco that doesn't have lights/sound/smoke, presumably. I have been convinced there may be a need for diesel and electric locos with multiple light options, but steam? Bachmann are transitioning to using 21 pin sockets on all their new models it would seem, but in particular it seems to be associated with anything that has provision for a speaker for a sound setup. Link to post Share on other sites More sharing options...
Bernard Lamb Posted October 17, 2011 Share Posted October 17, 2011 Perhaps in Hatfield things are different?? They were known to experience problems of this nature with certain aircraft parts. It happens. With toy trains rather more often than with aircraft. Toy trains are also a lot cheaper. I also find it infuriating but I doubt if having a rant on here, or taking any other action, will make a blind bit of difference. Bernard Link to post Share on other sites More sharing options...
34theletterbetweenB&D Posted October 17, 2011 Share Posted October 17, 2011 As for Hatfield: a flagship for design quality as the basis for end product reliability remains: Davall Gears. Link to post Share on other sites More sharing options...
craigwelsh Posted October 17, 2011 Share Posted October 17, 2011 The thread may have had a silly title but its produced some useful input as normal on rmweb; I'd known about the concept but didn't know it had such a great name - 'poka yoke' thanks chaps . The most common one at Bachmann is putting the morton clutch brake lever on the wrong side. Link to post Share on other sites More sharing options...
RMweb Premium spamcan61 Posted October 17, 2011 RMweb Premium Share Posted October 17, 2011 I might note at this point that one of the leading figures in pushing this quality revolution, Dr Joseph M Juran, lectured the American Association of Motor Manufacturers in 1962, telling them that the Japanese motor industry would tear them apart. They laughed then... Thing is, weren't many of these ideas American in origin anyway? I used to work with an ex Toyota UK process guy, he was six sigma black belt yada yada; anyway, he claimed that at least some of the ideas formalised by Juran et al. were originated by Americans supporting the post war rebuilding of Japanese industry. Link to post Share on other sites More sharing options...
mow Posted October 17, 2011 Share Posted October 17, 2011 Not adopting the poka yoke approach to assembly has higher costs - disgruntled customers, reworked items, wastage, hidden administration costs and an unquantifiable damage to reputation. Link to post Share on other sites More sharing options...
RMweb Premium spamcan61 Posted October 17, 2011 RMweb Premium Share Posted October 17, 2011 Not adopting the poka yoke approach to assembly has higher costs - disgruntled customers, reworked items, wastage, hidden administration costs and an unquantifiable damage to reputation. The costs are different, not necessarily higher, I've know companies spend millions to save thousands; poka yoke is like any other tool, there are appropriate and inappropriate times to use it. Link to post Share on other sites More sharing options...
RMweb Gold Oldddudders Posted October 17, 2011 RMweb Gold Share Posted October 17, 2011 Thing is, weren't many of these ideas American in origin anyway? I used to work with an ex Toyota UK process guy, he was six sigma black belt yada yada; anyway, he claimed that at least some of the ideas formalised by Juran et al. were originated by Americans supporting the post war rebuilding of Japanese industry. That was my understanding. The whole Quality issue was one of the key tenets of the US team - was his name Deming? - and the Japanese lapped it up on the basis that this must be the way that US industry was organised. Little did they realise that by so doing, they were putting themselves in the box seat for selling excellent goods worldwide, with the result we all know. Where is the Deming for China, I wonder? Not being a conquered nation, they may take a bit of convincing, especially as much of the developed world is now in debt to them. Link to post Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.