Horsetan Posted January 6, 2011 Share Posted January 6, 2011 ....I do not regard my advice as bad. .... Papal Infallibility? Sure the Pope sometimes says things he doesn't really mean, and.... Link to post Share on other sites More sharing options...
Kempenfelt Posted January 7, 2011 Share Posted January 7, 2011 Just a quick word of warning in response to Spocky's post, be aware that a metal vice will act as a heat sink! If you really do need to clamp the job, a possible sugestion would be to use pieces of wood (possibly pinch some coffee stiring sticks at the next available opportunity) to use to insulate the job from heat loss. I orginally used a piece of steel milled angle to ensure my folds were at right angles! When I was couldn't get my solder to flow, a quick chat to an expert soon identified the eror of my ways! Hope it helps! Link to post Share on other sites More sharing options...
bertiedog Posted January 7, 2011 Share Posted January 7, 2011 Small tip if you want extreme accuracy with soldering, it does not have to be done for everyday work, but especially adding things like tiny lamp brackets etc, it to paint office correction fluid around the area. it can be adjusted with the tip of a scalpel when dry, and then the parts slipped together and heat applied, the solder cannot over run past the correction fluid edges. The correction fluid wipes away with solvent. The smaller brass part can be pre tinned, the body does not need it, add a dash of flux to the body brass area, surrounded by the fluid. For small details the 148 medium melt solder will do fine, or use old scraps of whitemetal kit metal, melts at about 130 or so, and alloys correctly with brass. The technique still demands a powerful iron, with a small tip. despite the delicate work. Also, if you can't get leaded solder if is totally possible to make your own, 60% by weight lead free tin solder, to 40%by weight lead flashing sheet, Melt small amounts in a stainless steel bowl, (Poundland doggie bowl....), with a gas flame, remove any oxide dross from the molten metal with a metal spoon and pour out carefully in a strip on to a suitable surface, I use a sheet of aluminium, to cast a stick of perfectly good general purpose lead solder. Do not do this if you feel awkward with handling hot metal, but the quantity is very small, wear gloves and eye protection, and do not breath any fumes.. In line with the tighter regulations on lead, the leaded solder is still made, but in wire form it will get difficult to source, it's use remains legal and regulated for arts and crafts that demand it's use. Cored rosin fluxed leaded solder is already out of production, as it is for electrical uses and these uses now demand lead free solder is used. Another tip to carefully control the amount of solder added to the joins, is to pre-cut wire solder with cutters, into same sized tiny pellets, and add to the joint with tweezers. As the tinned iron heats the joint, and the flux, only a fixed amount of solder can run, the common error is to try to add more by applying the wire, but it is very difficult to get the right amount to melt, it only comes wit experience, and even then the pellets can help. Stephen. Link to post Share on other sites More sharing options...
craigwelsh Posted January 7, 2011 Share Posted January 7, 2011 I thought all military uses were exempt from being lead free and were still putting lead solder into their electronics. The high silver content lead free stuff seems ok as an alternative for electrical work though i'm not sure about the longevity of the joints compared to lead. - Build it rigid. Don't compensate or spring the chassis. A rigid chassis runs much better anyway as long as you weight the loco properly. Thats why no RTR's are compensated. Additional cost is the reason nothing too fancy is put into RTR; Bachmann don't even bother with axleboxes for example! Mind you some RTR like the Pannier tanks do have a sprung middle axle which is better than having it sitting higher than the outer two axle all of the time or having sloppy bearings. I hope the OP hasn't been put off by all this anyway, especially as we seem to have got into home made solder preparation guidelines now . Link to post Share on other sites More sharing options...
bertiedog Posted January 7, 2011 Share Posted January 7, 2011 In theory the tin solder should last much longer, bar a problem known as tin whiskers (google it), lead tin was estimated by the GPO (large user, research from Dollis hill lab), was that tin lead lasted about 50years without failure, but could fail at about 40, dependent on purity, but there are lots of electrical gear far older in working order. The GPO were setting very high standards to what they considered still un oxidised. As before notes are for all not just the original poster, if we all started new threads for each comment or advice then it would get even more complex, it is likely that those interested in soldering are reading the thread already. Stephen. Link to post Share on other sites More sharing options...
Kenton Posted January 7, 2011 Share Posted January 7, 2011 Another tip to carefully control the amount of solder added to the joins, is to pre-cut wire solder with cutters, into same sized tiny pellets, and add to the joint with tweezers. As the tinned iron heats the joint, and the flux, only a fixed amount of solder can run, the common error is to try to add more by applying the wire, but it is very difficult to get the right amount to melt, it only comes wit experience, and even then the pellets can help. This one is excellent and I have been doing it for years without remembering that it is a good tip for beginners. Using less solder in making a join is a lesson that is very hard to learn. The belief is that just a bit more solder will fill any gaps and hold the parts together better. This may be true to some extent for white metal work where it really isn't soldering but more like gluing with solder, but for brass n/s the smallest amount of solder is best. It took me many years to learn that so much time is saved by using less as the clean up chore is reduced almost to nothing. If you have a de-solder braid/wick and are using it for anything other than dismantling kits then you are using too much solder. Link to post Share on other sites More sharing options...
Sailor Charon Posted January 7, 2011 Share Posted January 7, 2011 Another tip to carefully control the amount of solder added to the joins, is to pre-cut wire solder with cutters, into same sized tiny pellets, and add to the joint with tweezers. As the tinned iron heats the joint, and the flux, only a fixed amount of solder can run, the common error is to try to add more by applying the wire, but it is very difficult to get the right amount to melt, it only comes wit experience, and even then the pellets can help. Stephen. Thanks for the tip. While I've soldered kits in the past, this year will be the first time I've ever tried to solder in N gauge - Come to think of it, I may have done it before, but until I read your post, I'd forgotten all about it. So yes, I think you've probably saved me quite a bit of trouble. (Because I've only been doing crude electrical soldering for the last couple of years) Link to post Share on other sites More sharing options...
bertiedog Posted January 7, 2011 Share Posted January 7, 2011 Going back to the GWR 7200 282 big tank, I remembered that the front step was the limit, not just the back, it is in the way of the required swing for tight curves. You can move the step forward as in the drawing attached, it does not look as bad as leaving it off. I rigged up the spare Cotswold 280 chassis with wheels, and a temporarily fitted rear bogie, and tried it on diminishing curves and the front step interferes in 00 at about 5 foot 6 inches. With the front step removed, or moved forward, the chassis with Hamblings wheels profiled to RP25 standard, normal back to back on a 13.5 width chassis goes around 3 foot 6 inches. This was pushed motion, not powered. I would expect all the currently available wheels would make no difference to the radius limit, although Markits Romford do have a slightly raised boss on the back that reduces side play available. Even with Ultrascale or Gibson would need thin metal washers to prevent the wheels rubbing on the chassis. If the rear step is exactly as scale it also hits the wheels flanges, but a small amount of moving back, about a 1mm or so will get the rear wheel to clear. The problems vanish in P4, but with the use of scale curves, but then the GWR had no curves....did it not? I would agree with Metropolitan that rigid chassis are OK, all things being made accurately, any play in the bearings etc., provides a bit of give. Most springing on 4mm models is far too generous, on a mid 1970's Kemilway chassis it had compensation beams that allowed 4mm movement up and down. more than a touch excessive. Most track we use is effectively dead flat, and a movement of .5mm is all that is needed, 1mm is a bit generous. only over a frog that causes the tyre to drop will the springing have any effect, there are no potholes on model track, or at least any I have seen. But with a long wheelbase the GWR 282, might have slight trouble over a hump, the transition between the grade and the flat, causing the middle wheels to be in contact, but the outer will float; hardly likely to derail, but it will rock n' roll fore and aft a bit, and also loose electrical contact with the front and rear wheelsets.. The reason few commercial makers fit springing is simply cost, it was fitted to Japanese HO brass as standard in the later years and the later locos ran better for it. Bachmann strive to keep costs low, there aren't even brass bearings in most of the range, but they do spring the middle axle, to improve pickup over slight humps. Stephen. Link to post Share on other sites More sharing options...
Metropolitan Posted January 7, 2011 Share Posted January 7, 2011 The reason few commercial makers fit springing is simply cost, it was fitted to Japanese HO brass as standard in the later years and the later locos ran better for it. Bachmann strive to keep costs low, there aren't even brass bearings in most of the range, but they do spring the middle axle, to improve pickup over slight humps. Stephen. Hi Stephen Whilst I agree with you that one reason why RTR loco's are not sprung is cost; another is that is not necessary! All my recent RTR steam loco purchases run with astonishing smoothness and never ever derail. What full springing can do is smooth out the action of the loco on the rails if that is of importance to the modeller. As far as I understand it, on a prototypical full sized steam loco the springs allowed for about 1" of movement on the driving axles. Thus, on our 4mm models, the springs should allow for no more than a thou or two of movement!..... And they say that giving the coupling rod holes 0.5mm of play is bodging!!! The odd spring is one thing to which I have no objection but the Sharman 3 point compensation system which seemed to catch on like a religion years ago, and which many kits cater for, is absolutely rubbish and should be avoided!! A rigid chassis, (with the odd sprung axle should you feel the urge), is simpler and will run much better! Link to post Share on other sites More sharing options...
bertiedog Posted January 7, 2011 Share Posted January 7, 2011 It is not a traction or de-railing issue with springing or the lack of, it is the even electrical pick up being lost when wheels on an unsprung loco come out of contact with the track. On a hump it is quite possible for an 060 to sit on two wheels only, and rock, the front and rear wheels draw no power. Mike Sharman demonstrated on a deliberately bad track, designed to cause problems to any loco but one with full springing, and power pickup remained at all times. Sprung locos do pull better, all wheels are in contact at all times. !mm springing equates approx to 2.8 inch movement on the real loco, so .5 mm is about correct, not just a few thou, nearly 20 thou movement, i have seen commercial locos with this sort of slop, or more, on unsprung chassis, which make them act as if sprung in a way.. The real nuisance of springing is to get the rate right, too stiff and it is next to useless, and also to make sure the side rods will operate with the up and down movement smoothly, it may work, but is it really smooth.in operation. Tri-ang solved it all, simply make the centre wheels so small they do not touch the track, it works!!!.or if your Hornby, thin the wheels and put smaller flanges,or fit flangeless trailing wheel..... Link to post Share on other sites More sharing options...
Metropolitan Posted January 7, 2011 Share Posted January 7, 2011 The odd spring is one thing to which I have no objection but the Sharman 3 point compensation system which seemed to catch on like a religion years ago, and which many kits cater for, is absolutely rubbish and should be avoided!! If it was rubbish, kit makers would not cater for it. I have no problem with it and i feel it works well, possibly not so well if not executed correctly. A few 7mm kits even use this method and just a little care works wonders (no sloppy con-rods etc! ) My Hornby Black 5 runs superbly. Immaculately. Without compensation. The reason kit makers felt the need to include this nonsense is that, regretfully, they listened to [Admin edit] It ain't the loco it's YOUR TRACK!!! Compensation is a waste of time!!! And, to be honest, so is springing. Weight is the real answer. Link to post Share on other sites More sharing options...
Metropolitan Posted January 7, 2011 Share Posted January 7, 2011 The odd spring is one thing to which I have no objection but the Sharman 3 point compensation system which seemed to catch on like a religion years ago, and which many kits cater for, is absolutely rubbish and should be avoided!! If it was rubbish, kit makers would not cater for it. I have no problem with it and i feel it works well, possibly not so well if not executed correctly. A few 7mm kits even use this method and just a little care works wonders (no sloppy con-rods etc! ) Yes they would. Kitmakers are like sheep. Sometimes I think they are their own worst enemies! Link to post Share on other sites More sharing options...
Kempenfelt Posted January 7, 2011 Share Posted January 7, 2011 Refering back to the OP, I see Scanman's build of a High Level pannier chassis has popped back up, please refer to this link if you haven't already seen it. http://www.rmweb.co.uk/community/index.php/topic/17831-grasshopper-minded/ This is a good example of what to expect from a High Level chassis and it looks like it's been made rigid and in accordance to the instructions. Alternatively if you look at my own blog you can get an idea of what is involved with the High Level Jinty chassis, however please be aware that I have diverted away from the instructions and have made my own alterations. These included incorporating compensation (as per the instructions), changing the horn blocks, adding a keeper plate and a buss bar, and eventually I will get round to installing wiper pick-ups as appose to the plunger pick-ups it was desinged for. Just a couple of variation of this type of chassis and examples of what can be produced from the kit. Hope it's of use! Best Wishes Paul Link to post Share on other sites More sharing options...
Jol Wilkinson Posted January 7, 2011 Share Posted January 7, 2011 My Hornby Black 5 runs superbly. Immaculately. Without compensation. The reason kit makers felt the need to include this nonsense is that, regretfully, they listened to [Admin edit] It ain't the loco it's YOUR TRACK!!! Compensation is a waste of time!!! And, to be honest, so is springing. Weight is the real answer. John, your comments clearly defines the difference that has developed over the years, between two of the main philosophies of 4mm modelling. The first eschews any developments that involve making loco chassis work more effectively (and we are talking kit building, not RTR which often has quite different reasons for their design parameters) - but happily welcomes new concepts such as DCC in the hope it will overcome the mechanical indifference of their models. The other, usually the EM/P4 modeller (but not always) having set out to work to more accurate wheel/gauge standards, look for ways to build better running models. You've fallen for the usual misbelief that weight will overcome all problems, that you can build chassis that are aligned to .0001", that your track - built on a wood substructure with cork/foam underlay and plastic track bases is accurate to the same degree. Even if you could build a chassis or track that accurately, are your Markits wheels also each to the same diametric accuracy? I very much doubt it. I have designed a number of loco kits in recent years. They have included sprung bogies or radial trucks and included the facility to incorporate compensation or springing if the builder wants to add it. Why, because thats what a number of customers want and that's how I would build the loco anyway, because it gives better electrical pickup, better traction and smoother running. So to incorporate the option into the design is sensible. Just stuffing a load of lead in the model will not produce the same results. What you do may work well enough to meet your requirements and modelling standards. But don't decry or try to belittle those that seek a better way, work to different standards, and in many cases produce very good models. Jol Link to post Share on other sites More sharing options...
Horsetan Posted January 7, 2011 Share Posted January 7, 2011 This is all getting reminiscent of the divide between Christianity and Islam. There's those of us who know that compensation / springing works and want it in their (kitbuilt/scratchbuilt) chassis. And then there's Metropolitan - you criticise him at your peril, for ye shall suffer eternal damnation, etc. :lol: Wars have started over less. All we wanted was a bit of an oul pray...... Link to post Share on other sites More sharing options...
Adrian Posted January 8, 2011 Share Posted January 8, 2011 This is all getting reminiscent of the divide between Christianity and Islam. There's those of us who know that compensation / springing works and want it in their (kitbuilt/scratchbuilt) chassis. And then there's Metropolitan - you criticise him at your peril, for ye shall suffer eternal damnation, etc. :lol: I was just going to say "Don't feed the troll", but that's usually self defeating - so I like your style! Link to post Share on other sites More sharing options...
Metropolitan Posted January 8, 2011 Share Posted January 8, 2011 John, your comments clearly defines the difference that has developed over the years, between two of the main philosophies of 4mm modelling. The first eschews any developments that involve making loco chassis work more effectively (and we are talking kit building, not RTR which often has quite different reasons for their design parameters) - but happily welcomes new concepts such as DCC in the hope it will overcome the mechanical indifference of their models. The other, usually the EM/P4 modeller (but not always) having set out to work to more accurate wheel/gauge standards, look for ways to build better running models. You've fallen for the usual misbelief that weight will overcome all problems, that you can build chassis that are aligned to .0001", that your track - built on a wood substructure with cork/foam underlay and plastic track bases is accurate to the same degree. Even if you could build a chassis or track that accurately, are your Markits wheels also each to the same diametric accuracy? I very much doubt it. I have designed a number of loco kits in recent years. They have included sprung bogies or radial trucks and included the facility to incorporate compensation or springing if the builder wants to add it. Why, because thats what a number of customers want and that's how I would build the loco anyway, because it gives better electrical pickup, better traction and smoother running. So to incorporate the option into the design is sensible. Just stuffing a load of lead in the model will not produce the same results. What you do may work well enough to meet your requirements and modelling standards. But don't decry or try to belittle those that seek a better way, work to different standards, and in many cases produce very good models. Jol Hi Jol I am not decrying anyone. And I am not in any way anti this or that standard or gauge. I do disagree that compensation makes for a better running loco. The reverse is true and I would be more than happy for any of my kit built locos to stand trial over your compensated ones on good, bad, and indifferent track! . Running quality is one thing I do get right! And I do not regard it as essential or wise for a beginner, about to embark on his first build (of a 2-8-0!), to have to worry about having to fiddle with beams and ridiculous hornblocks wobbling about everywhere. I agree that weight in not panacea for all ills. But it is important. I try to get the weight of the loco up to a point just before the wheels wont turn with the loco set against a buffer stop. The proof is there for all to see: The best running loco's at my local P4 club are RTR Co-Co and Bo-Bo Deisels or RTR 0-6-0's which have had their wheels removed and P4 wheelsets plonked in! Being RTR all are uncompensated or sprung. A Co-Co is in effect two 0-6-0's with tiddly wheels!! Is is easy to be blinded by a convention with which one has spent many years slavishly obeying. . Link to post Share on other sites More sharing options...
Kenton Posted January 8, 2011 Share Posted January 8, 2011 Perhaps I'm on John's side - a little bit here - (stands back and expects the same flaming that John appears to be receiving in this thread) First to reiterate somethings said earlier: - we are all entitle to express our experiences and expertise gained over the years in answer to the original question - as long as we respect that it may not be the only valid solution and that others may follow a different set of opinions/standards. - in a thread like this it is easy to forget that different people work to different standards and just because some people choose to work in OO does not make them less of a modeller than someone who works in P4 (or any so called "fine scale") The debate on compensation and springing could feed and fuel much heated debate and folk stamping feet in respective corners. The majority of good kit designers give us a choice in the matter. It is a choice that we usually make according to our view or stand on the "fine scale" argument. Those with P4 in mind will generally go to springing whereas those content in OO are also content in rigid chassis. I seem to fall somewhere in the middle. Most builds are rigid but some are not. I will not go out of my way to spring a chassis just for the sake of it or because someone has indicated it is possible (as nice as it is to know that) It is generally more complicated and time consuming and often far more trouble than it is worth. But I can see why it gets done and why it gets requested by people almost like it seems like the latest "must have". "My loco's fully sprung and DCC fitted, which means I'm better than you, ya-de-yah" At the end of the day you should do what works or feels right and worth the effort. Link to post Share on other sites More sharing options...
John_Hughes Posted January 8, 2011 Share Posted January 8, 2011 Depending on the circumstances it can actually be easier to build a compensated (or sprung) loco than a rigid one; it all depends on what you have to start with. For instance, I'm currently working on the chassis of a Wills Flatiron - very nicely designed by the excellent Mr. Sibley, but a total pain to put together as a rigid chassis; sprung, it offers almost no problems at all. Horses for courses! Link to post Share on other sites More sharing options...
MarkC Posted January 8, 2011 Share Posted January 8, 2011 Depending on the circumstances it can actually be easier to build a compensated (or sprung) loco than a rigid one; it all depends on what you have to start with. For instance, I'm currently working on the chassis of a Wills Flatiron - very nicely designed by the excellent Mr. Sibley, but a total pain to put together as a rigid chassis; sprung, it offers almost no problems at all. Horses for courses! It's one to be recommended, imo, as a 'first go' at compensation/springing, as it's got a little complexity (the bogie) but no outside valve gear to worry about. Mark Link to post Share on other sites More sharing options...
alastairq Posted January 8, 2011 Share Posted January 8, 2011 IN the sprung versus unsprung-weighs-more-than-a-brick, .and I subscribe to neither camp having had issues with both.....let us not forget the inimitable Guy Williams....whose masterpieces pounded the rails at Pendon for...how long? And who advocated unsprung chassis, tender-mounted motors, and what looked like depleted uranium superstructures.....? Mind, he also played the other side of the fence.... I agree with bertiedog.....the main issue I have suffered from is a difficulty keeping all the wheels doing the picking-up, in touch with the rails....trying to make a silky purse out of the sow's ear of an American MDC chassis has resulted in experiments to introduce some degree of flexibility in one or more axles..for the above reason. Link to post Share on other sites More sharing options...
John_Hughes Posted January 8, 2011 Share Posted January 8, 2011 It's one to be recommended, imo, as a 'first go' at compensation/springing, as it's got a little complexity (the bogie) but no outside valve gear to worry about. Mark Actually I was intending to just give the bogie plenty of weight, in the Guy Williams manner, and let it look after itself. Now you've made me think about doing more.... Link to post Share on other sites More sharing options...
PenrithBeacon Posted January 8, 2011 Share Posted January 8, 2011 I'm a total novice in loco building too and I've been attempting to build a chassis for a RTR engine for some time. I'm about to start on my third attempt! I have to say that much of the stuff that's been written here is no help at all. Is there a blog to which the tyro can attend? Regards Link to post Share on other sites More sharing options...
Kenton Posted January 8, 2011 Share Posted January 8, 2011 I'm a total novice in loco building too and I've been attempting to build a chassis for a RTR engine for some time. I'm about to start on my third attempt! I have to say that much of the stuff that's been written here is no help at all. Is there a blog to which the tyro can attend? Regards You could always start your own topic - being specific to the chassis you are trying to build posting what specifically seem to be your problems and detailing (pref with photos). The problem with this thread is that it has wandered a bit and the OP did intimate that it was not exactly novice territory - giving some of us the opportunity to wander off and "debate" some less than novice issues that always stir things up around the bar area at a show. Knowing what the exact chassis is will probably bring forward comments from someone who has actually built it as well as those with simply suggesting alternatives. If you have had 3 attempts you are probably in a pretty good position yourself to have a very clear idea of what is going wrong. Simple questions to ask are things like what gauge, what alignment jigs used, sprung/unsprung. Link to post Share on other sites More sharing options...
MarkC Posted January 8, 2011 Share Posted January 8, 2011 Actually I was intending to just give the bogie plenty of weight, in the Guy Williams manner, and let it look after itself. Now you've made me think about doing more.... It's very simple, John. The bogie's not sprung with the rest of the chassis; it's still basically a simple swinging arm/pivot to the body, with a light spring to hold it down. However, the clever bit is that one axle runs conventionally in plain holes, but the other moves up & down in slots, pivoting on a vertical plate in the centre. Have a go - you'll not regret it Cheers Mark Link to post Share on other sites More sharing options...
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