Scalefour Forum

Well, Paul Cram, I've made crossings up into soldered units by various means but was never convinced that tolerances of a few thou' could be met by sticking flexible plastic chairs round something to hold it. The position could also be easily influenced by the tracks leading off so I felt critical a...

It's all in the word "now". They weren't like this originally as my first post described although they used what is a very common arrangement.

DaveB

Sent this a while ago and it appeared then disappeared. This is second retry - am I barred? Right, I'll try again. Much of my layout was built over 25 years ago and I started using the latest technique back then which used plastic chairs and sleepers. I found it difficult to build stable crossings s...

Oops on a few scores there. The kit was derived from a GA of a vac fitted engine so that arrangement should be correct although this area of the drg is rather busy as the exhaust steam injector is down there too. These were later removed. I don't know where I derived the steam brake arrangement from...

Yes, re-inforcing plastic chaired pointwork with a few soldered sleepers concentrates stresses caused by thermal expansion and leads to failures so would suggest that you need Philip's or Enigma's mix for safety. I've used a couple of pcb sleepers to hold crossings and they just break off, same with...

I've been keeping out of this as it's so long ago since I built my J39 that there's no chance of me adding anything to what I've put in the instructions - or missed out, as the case may be. Now you have all the bits you should just be able to line up the cut-out to clear the axle and the hole that t...

When I lived down south there were some MM 45xxs being built and there weren't any reports of problems. I never heard of one maker being better than the other. Some of our group knew MM very well. With kits of this quality you can have faith and press on whereas there's been plenty in the forum wher...

You're completely ignoring the Masokits etched chairs which Julian has just used successfully - these must be the best way to make soldered pointwork. I recall that the negative comments about potential new point kits was genuine concern over whether the technique could meet the P4 tolerances and gi...

My Finney V2 is mostly half etched - it's ok when it's finished but it did wander about during construction. Some of it could be 2/3 rd etching. There's the odd full thickness strip to re-inforce - did you consider these? There's plenty of Finney kits been built.

DaveB

At least the prototype arrangement guided the hook at the front so there was a tendency to pull towards the track centre. With Jacksons installed by the book and no front guide it's an unstable arrangement, especially on curves where the couplings follow the chord. Sorry for deviation but I was poin...

For a long time I've felt that securing Jackson couplings to the opposite end of the vehicle can contribute to problems at crossings and elsewhere, particularly with longish or poor running trains and now use a pulling post behind the nearest axle as in MRJ 223. I suppose propelling round curved dia...

Careful here! Martin also warned about meeting P4 tolerances with cast chairs. I think we might wait for evidence that a P4 version of the product is possible. Poor bloke hasn't even got started yet. Is the Exctoscale product definitely done for? This is tried and tested - "oven ready" I t...

You've pretty much trashed the idea of P4 tolerances there, Philip. We've no idea what equipment Simon has - collets would do a nice job or perhaps soft jaws, although these don't seem to be available for mini-lathes. And 3 jaw chucks don't wobble if they are good quality, mounted correctly and not ...

Well, I can't get any of these common primers to stick to my models any better than plain gloss paint despite careful cleaning and degreasing. Perhaps, then, someone has the knowledge to give an answer to this question: they are all sold for use on car bodies which are essentially steel. Does this m...

I suggest you bend the check rail very sharply, Julian, despite knowing the prototype bend radius. This is a difficult area and the test is to see if a wagon can be pushed down the wrong way. I usually cheat with the filed bits too, making them just a little longer and sharper than the prototype blu...

Yes, it's easy to get them to run almost true but that last little nudge has always eluded me. My gauge has parallel faces but the axle slot is just a tiny bit out (it wasn't intended for this job) and that stuffs it up. They are a very nice wheel, however and even with a small wobble are very reluc...

Gauges were no longer available when I asked last Scalefourum and I've never managed to get the wheels running truly as I don't have one. The official instructions claim that the first wheel will go on square of its own account, given a bit of fiddling to get the position right. Guy uses his block h...

The purpose of the gaps is to allow for possible variations in the length of the plastic sleeve so care is necessary if working from this. We do, however, have the advantage that we can check the sleeve before going ahead - obviously not possible when designing the tooling. Wobbly wheels are still t...

5 thou' is more than 0.1mm which is pretty close to 4 thou'. Why do you want to put washers in the gaps and which will prevent you getting equal pin-point protrusion each end?

DaveB

The gaps don't have to be equal, just as long as you don't push the wheels up to the axle sleeve and expect the correct b-b. It's difficult to get these wheels to run true without the Exacto b-b gauge as you need to hold the axle perpendicular to the wheel due to the clearance in the hole. Just be s...

I agree completely, Terry, too much theorising and too many test planks. You can end up trying to build the perfect model and never getting anywhere. The first turnout you make won't be as good as the 20th so the sooner you start the better. Priorities change when you're building a complete layout. ...

You'll only get a suntan with UV so you're safe or disappointed, whatever your point of view.

DaveB

I started this earlier but it seems to answer your comment Dave. Assuming that here we are referring to the usual model fold along an etched line but if you change the geometry of a bend in any way, as in making it sharper, then it will not come out as the designer intended - or rather thought he in...

With motion parts, it's possible to assemble the joints off the engine so that they are nice and free but when placed on the chassis perhaps the conn rod gets a slight twist or the radius rod is pulled to one side so there is instant friction. This is worse with forked joints or when just trying to ...

My reason for suggesting supplementary heating was to avoid a time when there's no possibility of heat - a sort of warmer frost-stat, if you like. Of course some thermostats have this facility but I feel it needs to be a bit warmer than frost protection. My workshop is currently at about 12 deg so I...