Building an Ace Kits "K"

oldravendale

Western Thunderer
Very true, Peter, and even though I'll have done what I can the K will still be something of a compromise. The tender was a case in point, but after some considerable juggling it got there in the end, and I suspect the same will be true of the loco, although I'm advised that the basic dimensions are OK. However, I'm not making the eccentric main crankpins, for example, and the crankpin throw is insufficient for a K, so the Slaters wheels themselves are a compromise. However, the slidebars and motion bracket were quite offensive to the eye so deserved a bit of TLC.

Ultimately rule 1 will apply on the basis that, if it looks like a K, and drives like a K it probably is a K (but Nick Dunhill had better look away now:D).

B
 

oldravendale

Western Thunderer
I used my rolling bars for the first time to create the cylinder wrappers. I followed previous advice and loaded some thinnish brass ahead of each wrapper to avoid the flattened bit at the start, and also a piece of thin card to absorb the punched rivets (GW Rivet Machine). It worked beyond belief - no creases and a perfect curve on each which just needed a tweak to fit the cylinders like a gloves. For very nearly the first time the cylinder wrappers fit exactly, and there is actually a nice touch, there being a half etched rebate at front and back which naturally fits around the cylinder "armature".

I'd previously fitted a thin walled tube of 2.0 mm ID between the cylinder front and back in which the piston rods will slide. All in all a surprisingly creative day - surely the best for a long time on this kit.

Photos will follow in due course, but if the weather holds tomorrow will be a "masking the green and spraying the black" day on Evening Star......

Brian
 

Lancastrian

Western Thunderer
I have very similar problems with the Ace kit for the Urie H16. Thankfully LG have produced castings for motion parts, but the frames, bogie and pony truck etches are just about passable, whilst the motion brackets are useless.
 

oldravendale

Western Thunderer
Here are the promised update photos. They are not great quality - in fact :shit: - but I keep a snapshot camera in the workshop which is really not up to the job. Rather poorish pics than a potentially damaged DSLR......

100_0496.JPG

This is part of the fret produced for me by that nice Mr ST of this parish. Each cylinder back comprises four etch layers sweated together to give the correct chunky depth to the back of each cylinder. Additionally Simon has provided the glands to go on the rear of the cylinder backs. In comparison the two discs which have been released from the kit fret are what is supplied, one for the front and one for the back of each cylinder. They are both too small in diameter and give no impression of the actual appearance of the prototype.

In order to create the correct appearance for the front of the cylinders I'm currently producing these discs using the new versions as a pattern for size. They will also be created by sweating together from nickel silver to give the correct diameter and depth.

100_0497.JPG 100_0498.JPG 100_0499.JPG

These are the promised photos of the cylinders under construction. The cylinder claddings have been rolled to shape and are superb fits on the "armature". The use of rolling bars saved much time! The tube gives the LG piston rods some support and will be cut back flush once the new cylinder backs are in place.

Brian
 

oldravendale

Western Thunderer
Bet you thought I'd given up, but.............

100_0504 - Copy.JPG

Above is all the bits from Simon plus the cylinder parts from the original kit. The slidebars, motion bracket and cylinder backs and glands are made from multiple etches sweated together. The discs are the cylinder fronts which have been created from scratch and of which I am quite proud as they appear to actually be round! They comprise four layers sweated together. The parts remaining on the etch are the brackets to mount the slidebars on the frames. Note the twisty tabs on the motion brackets which made assembly a doddle.

Now we get to the dry run of fitting all the components together. The piston rod and crosshead are by Laurie Griffin. Otherwise parts are by Simon T, fitted to the original Ace kits carcass. After a bit of final fettling the crossheads slide smoothly, so I'm about to solder the whole lot up and move on. Clearances between the motion bracket and front wheel set are prototypically extremely tight - in fact I believe Simon thought I was working to S7 standards.

I wanted the cylinder/slide bar assembly to be removable so fitted a cross piece, drilled it and tapped accordingly. The motion brackets had no direct means of fixing, so I constructed a cross piece which slides in to place within slots in the frames and to which the motion brackets will be soldered. The slidebars are soldered to the cylinder backs and motion brackets, and thus the cylinders, slidebars and motion brackets can be removed as a single unit. 100_0511 - Copy.JPG 100_0513 - Copy.JPG 100_0514 - Copy.JPG 100_0515 - Copy.JPG 100_0516 - Copy.JPG
Brian
 

oldravendale

Western Thunderer
I've hit a problem and been wrestling with it, off and on, for most of this week.

Having completed the chassis using a chassis jig and the conn rods to set up the hornblocks the holes in the conn rods were opened out a trice using a reamer so that the chassis ran down an inclined bit of track as an 0-6-0 without any binding. In order to clear the inside of the slidebars the front crankpin screws have been replaced with 10BA threaded crankpins. (Although not relevant as they currently play no part I've also fettled the slidebars and crosshead to a smooth but not loose sliding fit and will finish them using the Brasso treatment). I fitted the motor/gearbox (Portescap), driving on the rear axle expecting all to be straightforward, and the chassis ran on the rolling road, initially a bit lumpy but over the course of a few minutes slowing down and eventually binding.

It was clear that at the ten past two position the right hand rear crankpin was solid, with no movement. The left hand rear crankpin was solid when it reached the quarter to three position. (Left hand leads at present, but I reckon that should be a right hand lead). I therefore cheated by opening out the rear crankpin hole in each conn rod using a reamer, reassembled and things were no better. I've now repeated this several times and feel I'm approaching the point where I'll have to bush the rear conn rod holes due to excessive slop! (I probably exaggerate, but you'll understand what I mean). Each time a rear conn rod seizes the crankpins on the other five wheels appear to have some freedom, so I've not, so far, opened out the crankpin holes for the front axles any further.

It appears that, by driving the centre wheel set, the problem goes away. Entirely! I've yet to actually move the motor to the centre wheels but I'm pretty confident that everything will run smoothly.

Note that I've built various, though not a huge number, of locos up to and including this, including (in reverse order) a 9F, A3, Adams Radial , Black Five - even a Dukedog with inside valve gear - and several 0-8-0s and 0-6-0s, so I'm not without some experience of making minor adjustments so that things run sweetly. This one, however, is just defeating me at the moment. And for once I believe it's not anything to do with the kit.

Does anyone have any thoughts about the next attack on the problem? It's now driving me nuts. I've currently taken the chassis back to wheels without conn rods, and all is free running. I've yet to remove the motor to check the free running of the chassis again without motor and with conn rods. At that time I may swap the centre wheel set for the rear just to see whether that makes any difference.

And while discussing things chassis-wise, does anyone know a source of threaded crankpins? I can make my own but would prefer to avoid the faff.

Brian
 

Steph Dale

Western Thunderer
Dad,

I've got some ideas, but need pictures.
1. What do the coupling rods look like? (Not con rods!)
2. With the chassis set up right hand lead indicate where the problem is/are, if it's still there!
3. A shot along the axle of an assembled wheelset - is the quartering; a. 90 degrees, b. greater than 90, c. less than 90?

You can check that the quartering is consistent on all wheels, if it's not that's a problem.

How does the chassis run on the track? The dynamics of running on a rolling road are different to those of running on track, and if you can't get it to do both then track running is the priority.

You've used all the crank pin bushes I did then? Must be your turn to do a batch:D

Steph
 

mickoo

Western Thunderer
On the W1 I found it ran fine on the track but a pig on the rolling road and I had a tight spot like yours under power and found one of the crank pins wasn't quite square.

MD
 

oldravendale

Western Thunderer
Thanks Mick and Steph.

I'll be back to you soon - today oi mostly be putting up fencing.

And yes, Steph, I meant coupling not conn rods.

B
 

richard carr

Western Thunderer
Brian

Are you certain the gearbox is fine, I once had a fault portescap where one of the side bearings was too large allowing the gear axle to weander around a bit, it never ran smoothly and was only fit for the bin.

Is your rolling road level and square, I use a baccus one and it's easy to get it a bit out of square.

Have you checked the wheels, slaters wheels can come lose as the screw doesn't always seat properly and the countersink can stop the wheel being locked onto the axle.

At least it's not the kit.

Richard
 

simond

Western Thunderer
Brian

your problem puzzles me too... Please try this and see what happens;

Roll your loco to a position where it locks up, then don't move it!
Take your tweezers and try to move the other end of whichever rod is jammed.
When I say "move it", I mean, to and fro along the axis of the crankpin.
I'm guessing that there is some axial play, and you will be able to tell if it moves.

If it does move, it's not a problem with the rods & chassis - which might point to wheel bearings or motor. If it doesn't move, then it seems to me that the rod is tight with respect to the chassis, or the quartering is out, as Steph suggested.

I'm not sure about your 10 past 2 / quarter to three positions... if the rods are tight when the wheels are at front or rear dead centre, but loose at top or bottom dead centre, then it's a spacing issue. on the other hand, if they're tight at 45 degrees... I'd be looking at quartering.

interested to hear how you get on
best
Simon
 

oldravendale

Western Thunderer
Thanks for these additional suggestions chaps. Here's an update on where I am now, having managed to grab 1 1/2 hours in the workshop yesterday evening.

Coupling rods were removed and the motor/gearbox run on just the rear wheel set. Sweet as a nut, so I'm confident it's not the Portescap. Rolling road checked for squareness. It'd be difficult to get out of square - it's called a Locolocs or something similar and I bought it from Chris Basten several years ago. Locos running in on it can sometimes be a bit lumpy but have never locked up previously. Wheels and fitting have been checked and have not come loose on the axles.

Wheels were then removed from the axles and re-quartered, right hand leading. At the same time I checked the washers on each axle to ensure they are the same both sides and I'd not picked up two different thicknesses in error. Chassis was then pushed up and down a piece of track, and let run by gravity by lifting each end in turn. This was done at least a dozen times and there were no problems. Coupling rods were refitted and the same process followed. The chassis ran under gravity as smoothly as any I have ever built before.

Cup of tea and scratched head, thinking that I may have accidentally adjusted something which has corrected the problem. Back on the bench and idly ran the chassis back and forth, back and forth under gravity whilst cogitating about what might have given the problem - after all, I'd like to know so that I can avoid doing it again! Then, out of the blue, it locked up. I'd followed the process Simon has proposed previously, checking the movement of the rods on the axis of the crankpin, and did it again. Once again the coupling rods are locking up on the rear wheels. Duly released and run up and down again, and eventually it locked up again. On the next occasion I took a torch and checked to see if any components were simply binding on one another, but there is clear air behind the wheels and behind the rods.

Once again I'm at a loss. I cannot see how a chassis will run smoothly and then suddenly change characteristics.

Any new suggestions?

Brian
 

richard carr

Western Thunderer
Brian

Something is catching somewhere, it could be one of the crankpin screws, the head just catching the frames in a certain position normally of course its fine. Too much side play is the cause.

Other than bring it to Telford and we can all have a look at it.

Richard
 

Steph Dale

Western Thunderer
Dad,

Next time it locks up try tapping each of the coupling rods in turn and see which one is tight - that way you will at least be able to start working out where to look.

Did you take any photos of the chassis made up? We're all still working blind...

Steph
 

oldravendale

Western Thunderer
Thanks Richard.

Crankpin screws are countersunk in to the wheels. Knuckle pins are filed back to ensure that they don't foul the wheels (they did initially but had already been filed back).

Steph - I will take photos but no time right now. Garden stuff is getting in the way, and I'm fishing tomorrow, starting at stupid o'clock. Hopefully I'll get to it on Tuesday.

Thanks for the comments.

B
 
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