bluestag

CSB is fine for six and eight and ten coupleds. The article I referenced is about compensation being used to shift 60% of the weight of a loco onto a single driver. It is easier to set up than CSB as well.

Simple mistake.

It's in 7mm. I have bought built up a couple of 7mm locos with rigid drivers, and they run fine. I do like sprung and compensated, as a rule. My 0-4-0 4' shunter was my first 7mm loco. It is compensated on classic Sharman principles: the driven axle is rigid, and the front axle rocks. As long as the wheels are reasonably clean, it runs well. But this loco was designed as a rigid chassis with a front sprung axle.

I'm well along building a 7mm Modeller's World LNWR Precedent (Jumbo). The kit is easily 40 years old, although it was developed somewhat by Mercian, apparently. Mine is an OLD one. It is of course a 2-4-0. I am building it with the drivers rigid, and the leading axle sprung with a Slaters unit. I had it running on 6'9" drivers, but found the kit was designed for smaller wheels; 6'6". I put them in last night. This lowers the chassis by about .75mm. Previously the front axle would derail on certain points. The wheel would climb up the check rail and run over it. Now it does not. So far, so good. At this point the chassis is running as a single wheeler, with the motor on the front driver. My track is not utterly flat, and at times the little bit of vertical movement left on the front axle lifts the driver to cause it to spin. I'd like to defeat that. So I have conflicting aims. Keep the carrying wheels on the track, and get traction on the center axle. Somewhere in the distant past I seem to remember someone advancing a rule to limit the vertical rise of an axle to less than the flange depth. Does anyone with experience have any opinion?

If you can, get and read a copy of MRJ 20. There is an article in there about compensating a 4mm single, and getting it to haul.

While waiting for bits for the loco, I have nearly finished the tender.

Now the blasted thing is derailing regularly on the inside curve of a Peco turnout, coming in from the toe end. The leading wheel gets half way along the check rail, and climbs up over it. There is no play on the drivers at all. The front end skews hard over, too far because there will be a set of spats hiding the sandboxes, which the wheels will foul. I have the front axle having movement upward, such that it does not lift the drivers off the track. Possibly too much, reducing the amount of down force from the Slaters springs. I MAY have to strip down the chassis and install narrower frame spaces, and allow the rear axle some side movement. Drat!

No, he photoetches other people's drawings. I need soup to nuts. Kevin

He retired several years ago. And he could find no quality etchers.

Yes. It's pretty limited, though.

Making headway. The tender is on loan from my A Class. May not be able to do much over the next week as I need my chum's rolling bars for the boiler. Not seeing him until the Sunday after next. This sure is a simplistic kit, but it is the only one for a Precedent, so I just have to do what I can.

Hey guys, Who will custom etch name (curved) and numberplates for my 7mm LNWR Precedent. I thought Narrow Planet, who have produced all my numberplates, would do it, but they say they can't do a curved nameplate. Kevin

The disc has already been cut out. It was never marked. I soldered the prototype disc to some brass stock and cut and filed the stock down to a disc. There was no place to put the pivot of a compass.

Yes, I was scribing the lines with an xacto knife. One gets pretty fine lines.

That's a NICE tool! Wish I had one. And it's the right size.

That would demand accuracy as much or more than the technique I used.

The circle has to be a very exact diameter. I soldered the former from the kit that is supposed to go in the smokebox to a bit of brass and fretted and filed until I had a copy.

I'm jealous. Where DO you find Mashimas these days? I'd use an 1824 if I could get one. (Not a 1624?)

Ken, What size motor is that? I'm starting a build on a LNWR Precedent from an OLD Modeller's World kit. I started with an 1833 Mashima on the front of the forward driven axle, but it is taking too much room in the firebox. It is just a mm or two too long to stand upright, leaving the firebox clear for lead. I'm going to try a 1524, not as powerful but leaving me all sorts of room for weight. The Precedent, despite being wildly successful, was in fact a fairly small loco. Kevin

To answer my own question. I blued the disc with a blue sharpie. I drew two chords on the face of the disc. Using a ruler, they were four 7mm scale feet across. Or as well as I could, and marked the half way point. As well as I could. Then used the end of the rule for a square, drew two lines perpendicular to the chords, at their half way points. Where they cross is the putative center of the disc. I have a nice small compass, with two sharp points and a screw to set the width very exactly. I was able to feel the intersection of the two scribed lines, and measure out to the perimeter. Then a 30thou drill (.75mm?) was felt into the point, and a small divot made. The compass was used again to judge how true the divot was. The divot was drifted as needed by holding the drill off perpendicular, and deepening the divot slightly. Measured again. Repeat about four times until the center was judged to be within 5 thou of being correct. Drill thru. The cab face is half etched down where it is visible, with rivets and other detail left proud. There is a half circle defining the land for the boiler. The disc was laid on the face of the cab, and being a bit smaller (16 thou or there abouts) than the land on the cab, it was possible to judge the placement of the disc as centered. The drill bit was brought to bare, and a divot created. Once it was a few thou deep, it was possible to see it thru the hole in the disc. It was off a bit, so again the divot was drifted. Eventually I drilled thru. Then both pieces were drilled out to clear the screw that would hold them together. A screw was soldered to the disc, and a nut run on it to tie it to the cab face. The alignment was NOT perfect. Not to worry. Try though I might, I had not drilled the hole in the disc perfectly on center. I dialed the disc around on the face of the cab, and found an alignment that was quite close. I scribed a line in the disc to define the ideal alignment, and hey presto. An hour's worth of work and two jewler's saw blades later, I am ready to make temporary connections between the cab and boiler. I do hate to be rushed!

I have made a disc, the same diameter of the disc supplied with a loco kit. The 2nd one has a large hole in the middle. It is a former for the boiler. I want the firebox to have one as well, with a small hole as perfectly in the center as I can achieve, for a small screw to clamp it to the cab face. So that I don't need to solder the boiler to the cab prematurely. I've googled it, and found a few suggestions. All of which look manageable with wooden discs six inches or larger. My disc is a bit over 1", and marking out on it is a challenge. Does anyone have a method that is achievable on such a small disc? 16thou brass, btw. Kevin

Yes. I have a sinking feeling about the boiler, which has the bands etched proud. They look a bit narrow to me compared to Fox transfers. Tomorrow I'll cut a bit of transfer out and apply it to the etching. I would not be surprised to see that making a new boiler is advisable. The only holes in the boiler are for the chimney etc. None of the smaller fittings are provided for. Oh well, it is no Finney kit.

Got a set of instructions from a chap on Gauge O Guild site. Thanks to everybody. Did not know better: the kit was intended to be built with undersized wheels (6' 6" rather than the 6' 9" wheels I bought. I will admit that the clearances of the foot plate vs flanges is almost non existent. Don't know if the splashers will fit the scale wheels or not. Just got to forge ahead. I'm surprised to say that I learned little from the instructions, meaning that it is an indifferent kit. But I need a Precedent! It seems that it is a feature, not a bug, of the kits for the Cauliflower and the Precedent that the frames be WAY wide. I fitted the top hat bearings from the outside. The instructions have them going in from the inside. How I'm supposed to fit plunger pickups is a mystery. But never mind. There are not provisions in the kit for plungers. I built it with 26.35mm spacers, and it all seems well. As long as there are springs on the front axle, it seems to hold the road. Still waiting for coupling rods from Premier. So it runs as a single wheeler for now. And I'm going to put in a smaller motor to allow more lead in the firebox. Hopefully the loco will weigh more than 1.5 lbs, without burning out the new 1525. News as it comes in.

Got a set of instructions from a chap on Gauge O Guild site. Thanks to everybody. Did not know better: the kit was intended to be built with undersized wheels (6' 6" rather than the 6' 9" wheels I bought. I will admit that the clearances of the foot plate vs flanges is almost non existent. Don't know if the splashers will fit the scale wheels or not. Just got to forge ahead. I'm surprised to say that I learned little from the instructions, meaning that it is an indifferent kit. But I need a Precedent! It seems that it is a feature, not a bug, of the kits for the Cauliflower and the Precedent that the frames be WAY wide. I fitted the top hat bearings from the outside. The instructions have them going in from the inside. How I'm supposed to fit plunger pickups is a mystery. But never mind. There are not provisions in the kit for plungers. I built it with 26.35mm spacers, and it all seems well. As long as there are springs on the front axle, it seems to hold the road. Still waiting for coupling rods from Premier. So it runs as a single wheeler for now. And I'm going to put in a smaller motor to allow more lead in the firebox. Hopefully the loco will weigh more than 1.5 lbs, without burning out the new 1525. News as it comes in.

Going to try a 1525, which will fit vertically and free up all the smokebox for lead, just the ticket in a 2-4-0.