Post by paultomlinson on Jun 28, 2007 12:19:06 GMT
Hi Mike Hopefully you can borrow a jig but don't hold your breath! Don't know if you have access but I intend to drill/ream holes through the axles as per the real thing and then it's simply a case of using a flat surface, a rod through the axle with a spacer the same size as the crankpin set up against a square. Hopefully MW have accurately keyed the axles and wheels. What do you think about the quality of the bits in this kit compared to other kits? I see we are fitting an axle pump but the tender does not have a provision for a water feed and return, a question I put to MW some time ago and never got a response. Paul
Post by paultomlinson on Jun 28, 2007 17:59:22 GMT
Mike Forgot to mention before you stick the wheels to the axles, you will find that the recess on the back of the wheels has not been turned to the correct diameter so the balance weight plate will not fit. Looks as though the wheels will have to be returned to MW unless you can do the machining yourself. Paul.
The keying of the axles and wheels on my Britannia was very accurate and I didn't use a jig.
My Britannia tender has only one feed from the handpump and one other feed, plus a return pipe for the axle pump bypass. I suspect that the plan is to feed from the handpump outlet to the axlepump inlet, and to feed both injectors from the other feed. I'm not sure if it's a good idea to feed the handpump through the axlepump, since a failure of the axlepump O-ring and packing would then cause the handpump not to work. The boiler does have 4 clack valves, so there's an inconsistency somewhere.
Post by paultomlinson on Jun 28, 2007 20:45:27 GMT
Hi John On the Duchess tender there are two water valves presumably for two injectors, a feed from the handpump and even if the axle pump feed was taken from the handpump (not a great idea) there is still no return to the tender tank. If only MW would reply to my telephone calls and emails! Paul.
Ps, any news on the Britannia parts as this was supposed to be taking priority?
Well, thanks to Paul and JJ! I guess its not worth worrying about checking the quartering based on JJ experiences, so be it, one less worry. The quality seems about the same as previous kits, yes the inside balance weight plates don't fit, but I'm sure that I can butcher them to fit accordingly; it looks like all the bolt holes between them should line up. Michael Breeze's drawings only show two water feeds, one a force feed from the pump and one from the strainer in the bottom of the tank. So, I've no idea how MW's are going to do it, but I don't really care either, its up to them to 'deliver' a proper functioning water feed system, and we're a long way off completion....... Do you like the swarfe? I was given a bag of swarfe collected from under Fred Dibnah's lathe, (and there's a letter of authentication with the bag!), so guess what's going in my araldite mixture! Can't weight to get on with it. Enjoy the fettling, Mike
Hi MIke I'll check my wheel quartering on a jig and let you know(will be a while though, just about to go on holiday) As for the swarf! That's something I'll not be using, note that not all the cavities of the balance weights were filled so might be worth some investigation. If you do fill the cavities then I would recommend plastic padding (metal variety), it's very easy to file and leaves a good finish. Paul.
Post by paultomlinson on Jun 30, 2007 18:58:44 GMT
Just spent the day working on the wheels and axles. I have turned the faces of the wheels, the original machining resembled that of a ploughed field.Whilst I was working on the face I also turned the recess to a full .035" to allow the balance weight plate to sit flush with the wheel. I increased the diameter of the recess on the back of the wheelto allow the balance weight to sit correctly. Whilst on the back I machined the step of the spokes away, looks a lot better now. The quality of the wheel castings varied enormously, there was a considerable amount of flash between the spokes of one wheel requiring a hacksaw and some filing. I have drilled the axles as per the prototype to allow me to use a jig to check the quartering. Unlike all the other axles supplied so far, these axles did not have a square shoulder for the wheels to sit up against, two minute job with a parting tool sorted that one out. This needs to be looked at so the wheels can sit square at the correct back to back measurement. More info in a couple of weeks but now off to seek some sun!! Paul.
Post by paultomlinson on Jul 16, 2007 17:19:50 GMT
Ah, back to the grindstone after a couple of weeks away. Almost finished the wheels today including balance weights. Anyone tried fitting the sheaves around the eccentrics? You will find it's a great inteference fit and it took me an awful long time to get these things to rotate smoothly. Paul
That jig on e-bay will only deal with wheels up to 5 and 3/4" and I suspect the Duchess wheels are around 7". The jig looks exactly like the one illustrated in "Model Steam Lococmotives" by Tim Coles published in 1986. He explains how to use it and even 20 years ago was advocating Loctite to secure the wheels.
If anyone is interested I can e-mail them the relevant 2 pages. Regards Jim
Thanks to Brian for spotting the jig, and to Jim - yes, its too small! I've arranged for a friend to check the wheels to ensure that the quartering is correct, and he is also resolving the MW mis-machining so that the balance weights will fit properly; thanks to Paul for the heads-up on that problem! Just got to get the eccentric sheaves sorted now........ Best wishes, Mike
Post by paultomlinson on Jul 31, 2007 20:04:40 GMT
And another thing Mike....... Before painting your lubricator boxes, make sure that they fit the chassis. On mine they would not sit far enough down due to the brake cylinder stretcher., I had to mill .090" off part of the base to get the required clearance. Not convinced the main springs are strong enough so I am replacing these with dummy leaf springs around a coil spring so I can adjust the weight on each driving wheel as required. Made a pair of guard irons today for the bogie, surprised they are not included in the kit. Replaced the front coupling hook and coupling with one of the correct LMS style. All axles now finished and painted so should get the wheels on this week, let you know about the quartering shortly. Paul.
Well Ishould have known better. I have spent some considerable time working on the wheels and axles and finally I came to stick them together this evening. Once set I have measured the"quartering". One set is at 89.2 degrees, one at 86.8 degrees and one at 86.1 degrees. How's that for accuracy?...CRAP! I will now have a devil of a job separating the wheels as I have used Loctite 603. I assumed the quartering would have been accurate as everything is CNC machined, what a mistake. If anyone knows how to dissolve Loctite 603 could they let me know. Paul.
Paul I generally use heat. If it will fit in the oven about 200C seems to work. If is is too big I use gentle heat from a blow tourch. The loctite note sugests 250 but things usually can be parted before reaching 250.
Thanks for the warning Paul! Loctite's website gives the same advise as Julia.... circa Gas-Mark 8! Pity about the quartering; which is the reason for the origins of this post; the key-ways are machine cut, but human indexed. Another MW 'mistake'? How are the other Duchess Builders doing, no sign of anything from Jason... If any of them are reading this and don't want to post, It would be nice to hear from them by way of a PM if they would like to get in touch. Rgds, Mike
Managed to take one wheel off each axle without resort to heat. A brass drift and a big hammer!!! Wheels now back on, quartered properly and pinned with silver steel. I do hope MW are reading this and will help their other customers. Paul
I'm sorry if my comments on the accurate quartering of the Britannia wheels led you to glue the wheels prematurely.
The procedure that Ian at Modelworks recommended to me was to key and glue the 3 wheels on one side and fit their coupling rods, then key the wheels on the other side without gluing and find which two of these gave the smoothest rotation with their coupling rods fitted, and glue these 2, then fit the final wheel and coupling rod without its key, mark a line across the wheel and axle, glue it on this alignment without the key, then finally file the key to fit and glue it in. In practice my wheels still turned freely with the key in the final unglued wheel, so I glued it with its key in place; there was then a very slight stiffness at the 45 degree positions, but this disappeared after a few minutes running on air. I don't know if the axles were all at exactly 90 degrees, but they must have all been at pretty much the same angle and I guess that's what matters.