Horsetan Posted February 19, 2013 Share Posted February 19, 2013 I thought Eileen's did spring steel wire. Could you not use that? Link to post Share on other sites More sharing options...
Adrian Posted February 19, 2013 Share Posted February 19, 2013 Question: For springing for csb's, can I use WOUND guitar wire, or must it be plain? I'm sure I read somewhere that Adrian (Cherry??) had used 0.9mm wire to suspend a 7mm Jinty? I've asked at the local music store and theirs only goes up to 0.7mm plain. And they don't do piano wire. It may well have been one of my postings, don't use wound guitar wire then inner core will be too small. You should be able to get spring wire from any local model engineering firm, alternatively one of the online shops. I got mine from Folkestone engineering who do a range from 0.7mm to 1.6mm. Link to post Share on other sites More sharing options...
JeffP Posted February 19, 2013 Author Share Posted February 19, 2013 Ah...thanks Adrian. I suppose I ought to start at 1.0 mm and work up if needed? Link to post Share on other sites More sharing options...
Miss Prism Posted February 20, 2013 Share Posted February 20, 2013 I suppose I ought to start at 1.0 mm and work up if needed? No. The first step is to determine what the loco might weigh. Jazz's Duchess weighs in at 1.25kg, whereas a whitemetal-boilered DJH A2 box weighs in at a monster 4kg (including tender), say 3kg for the loco. That's quite a difference. Weigh your bits, Jeff. After that, assume say 70% of the loco weight will be carried by your drivers. If your loco is 1.5kg, then a steel beam of 0.6mm diameter would be suitable. If your loco is 2.5kg, 0.7mm diameter would be suitable. Link to post Share on other sites More sharing options...
JeffP Posted February 20, 2013 Author Share Posted February 20, 2013 Ah...thanks for that. I'll weigh it now: result: 2.807 kg, including box, wheels, sundry spares, all etches etc, but no motor or gearbox. I'd GUESS at around the 2.5kg mark when built. Ought I to be more accurate? Just the loco bits and it's wheels, no box etc? Link to post Share on other sites More sharing options...
ozzyo Posted February 20, 2013 Share Posted February 20, 2013 Hello JeffP, I think that I'd go for loco etches and casting only. I would say that the wheels don't count nor the motor and gearbox (mounted on the axle). After the loco is built you can get a better weight for it. Just had a look on the Markits web site and they do handrail pilers for the WDs in both 7mm and 10mm that could be of use to you for the CSB mounting points. OzzyO. PS. as it's your first time at using CBSs I'd start on the tender. If you make a ball's of it it will cost you less to replace it, than it would the loco frames. Link to post Share on other sites More sharing options...
Miss Prism Posted February 20, 2013 Share Posted February 20, 2013 Ought I to be more accurate? No need. All you are after at this stage is a ballpark figure. What this does tell us though is that the bookies' clear favourite for your beam is 0.7mm diameter. (So no need to stock up on extra sizes of spring, unless you want to weight it up to 4kg, and you'd need only to go to 0.8mm for that.) You also now know that the hole (in frame and hornblock fulcrum points) does not need to be significantly greater than 0.7mm. (Suggest 0.9mm or 1mm will be suitable - it doesn't matter much.) Btw, I'm thinking 0.8mm to 0.9mm deflection for your drivers. Link to post Share on other sites More sharing options...
JeffP Posted February 20, 2013 Author Share Posted February 20, 2013 What do you think of Ozzy's idea to start with the tender? Then I need another eight hornguides and hornblocks....Whose ought I to use on the tender? Link to post Share on other sites More sharing options...
ozzyo Posted February 20, 2013 Share Posted February 20, 2013 What do you think of Ozzy's idea to start with the tender? Then I need another eight hornguides and hornblocks....Whose ought I to use on the tender? Hello JeffP, sorry to reply to a question about why to start on the tender that I recommended as your starting point. But this is why I'd use this as my starting point. 1). less cost to replace, if you make a balls up of it. 2) you have a set of horn blocks that you can use that won't be seen, the M.F. ones you have, you have said that these are designed for beam compensation so the top of them will be missing from them. 3) you will not be able to see them so if these are not right so what? On the loco would you be able to see the horn guilds, I think not. 4) On all 7mm builds you will have to think ahead and try and see what you will require. 5) YOU have to start somewhere. 6) so why start at the hardest part the loco? OzzyO. PS. if you start on the tender you can use it for any tests that you want to under take as well. No valve gear or any of that sort of thing to get in the way. PPS. after all the locos I have built I still like to start on the tender. It's a bit of a bu99er when it's a tank loco though. Link to post Share on other sites More sharing options...
JeffP Posted February 20, 2013 Author Share Posted February 20, 2013 OK, point(s) taken. The tender it shall be. Now, where to source an eight-pack of hornblocks.............? Edited to say: an hour's searching hasn't turned up ANY machined hornblock bearings on their own. Anybody point me in the right direction, please? Link to post Share on other sites More sharing options...
Miss Prism Posted February 21, 2013 Share Posted February 21, 2013 I'm not sufficiently familiar with what's available in 7mm, but assuming that you have rejected the use of the normal range of Slaters hornblocks or the more expensive Hobby Holidays ballrace ones, it looks like you could be making your own. Something square with a 3/16" bore through it, held between horncheeks of bits of angle secured to the inner frames, will suffice. Longitudinal accuracy is not required because no rods are involved, so the block does not need to be slotted. Height consistency (bore axis to top face) of the blocks will however be required if you are CSB-ing the tender. Link to post Share on other sites More sharing options...
dibateg Posted February 21, 2013 Share Posted February 21, 2013 Jeff - Meteor Models do some, these are the ones I always use:- http://www.meteormodels.com/www.meteormodels.gbr.cc/info.php?p=10 Link to post Share on other sites More sharing options...
JeffP Posted February 21, 2013 Author Share Posted February 21, 2013 I've bought some of those for the loco, not cheap, are they? But I was after the actual square bearings, rather than the whole hornblock, since a) they won't be seen under the tender and b ) even if they were, they would be wrong, the tenders used outside bearings. I'll look at making some, or getting some made. Link to post Share on other sites More sharing options...
dibateg Posted February 21, 2013 Share Posted February 21, 2013 Or - you could use standard round bearings that slide up and down in a slot in the frames. Solder some brass wire to them on the inside, that can stick up vertically in the chassis and pass through a hole in the floor/home made bracket. That arrangement will allow vertical movement, but prevent rotation - and is cheap! Cheers Tony Link to post Share on other sites More sharing options...
Miss Prism Posted February 21, 2013 Share Posted February 21, 2013 Or - you could use standard round bearings that slide up and down in a slot in the frames. Solder some brass wire to them on the inside, that can stick up vertically in the chassis and pass through a hole in the floor/home made bracket. That arrangement will allow vertical movement, but prevent rotation - and is cheap! Yep, and it is a small step from that to convert the sticky up thing into a CSB carrier: http://clag.org.uk/pics/csb-gallery/will-litch-tender-1.jpg (These carriers are jig constructed, to ensure consistent axle bore to beam axis, as detailed here.) Link to post Share on other sites More sharing options...
JeffP Posted February 21, 2013 Author Share Posted February 21, 2013 Any links to the bearings, the round ones? Thanks. Or I might invest in a small parting off tool with 1.35mm blade, some 5/16th brass bar from Eileens and have a go........ Alternatively, I may cheat, take one up the road to my eldest lad's mate, and ask him to machine me some up at work. Link to post Share on other sites More sharing options...
Adrian Posted February 21, 2013 Share Posted February 21, 2013 Any links to the bearings, the round ones? I would have thought you'd already have some in the kit. Link to post Share on other sites More sharing options...
Grasshopper John Posted February 21, 2013 Share Posted February 21, 2013 Well I'l go to top of our stairs and stamp on a grape Jeff your going to build and 7mm at that. I am seriously thinking of 7mm down the road. What you will find ( If you dont already ) is that you cannot have enough tools, since i took up this hobby i have a nice collection already and there is room for more I will follow you with interest Jeff, bout time as well. ATB Grasshopper Link to post Share on other sites More sharing options...
3 link Posted February 21, 2013 Share Posted February 21, 2013 Well I'l go to top of our stairs and stamp on a grape Jeff your going to build and 7mm at that. I am seriously thinking of 7mm down the road. What you will find ( If you dont already ) is that you cannot have enough tools, since i took up this hobby i have a nice collection already and there is room for more I will follow you with interest Jeff, bout time as well. ATB Grasshopper Whoaa..... hold your horses, it still hasn't started yet , nearly two whole pages and not a soldering iron raised in anger . Martyn. Link to post Share on other sites More sharing options...
Horsetan Posted February 21, 2013 Share Posted February 21, 2013 Whoaa..... hold your horses, it still hasn't started yet , nearly two whole pages and not a soldering iron raised in anger . I like the way that Jeff is thinking aloud about what he needs, and chasing down every potential problem. The other side of the coin is that he could also be raising as many hurdles as possible in order to give himself a reason not to build it..... Link to post Share on other sites More sharing options...
N15class Posted February 22, 2013 Share Posted February 22, 2013 I always find it is easier to solve the problems as I am building, if I think to much before I start I start to find problems that dont exist. I often borrow one bit or another from a different kit, to save time and order the part and put replacement back. Come on Jeff just get started most of your worries will fade away as you work. Link to post Share on other sites More sharing options...
ozzyo Posted February 22, 2013 Share Posted February 22, 2013 Hello JeffP, is this the sort of thing that your after? This is how they come, it's in six's but I could do you a set of eight, or more. Let me know if you want any and I'll work out a price for you. Or you could get them from J.L.T.R.T. OzzyO. Link to post Share on other sites More sharing options...
JeffP Posted February 22, 2013 Author Share Posted February 22, 2013 It's most likely that work will begin on Monday next week, since the better half has been on holiday this week and keeps wanting to go places and do stuff, usually shopping....... I'm now waiting my parting off tool and a piece of 5/16th square brass to have a go with. I shall also have to purchase a 3/16th drill, since all mine are metric. There ARE bearings in the kit, but they aren't slotted, just meant to go through the frames and be soldered in. Thanks Ozzy, those look to be what I need, the actual bearing, not the horncheeks(?? Hornguides?) I'll have a go at making some, now I've gone to the extent of ordering the bits, but may get back to you if I'm not satisfied with the ones I manage to produce. Thanks for the offer. Your post appeared while I was in the middle of writing this, hence the edit. Link to post Share on other sites More sharing options...
Grasshopper John Posted February 22, 2013 Share Posted February 22, 2013 SWMBO surely knows were the shops are Jeff, Building is Faaaaar better than window shopping. stop stalling man, this is not a springboard its the 10M straight in jobbie get in there and Dae somethin Grasshopper J. Link to post Share on other sites More sharing options...
Western Star Posted February 22, 2013 Share Posted February 22, 2013 I shall also have to purchase a 3/16th drill, since all mine are metric. If you are thinking of using the drill to produce the bore for the axle... then maybe drill undersize and then use a taper reamer so that the axle just slides into the bore without tightness or rock. regards, Graham Link to post Share on other sites More sharing options...
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