122 Dmu

Simon

Flying Squad
Bit busy over the weekend, but tonight I have sanded down the epoxy filler on the roof edges and added plastikard to the roof "downstand" in order to lose the inward bow on one side.

The filler sands beautifully and the resulting edge is good and durable - very impressive.

Sanded.jpg

As this picture shows, on the "pushed out" side I could really do with running some more filler along the roof's edge towards the middle of the vehicle so that the roof edge is parallel to the top of the bodyside. I'd get away with not doing it, but will persevere as although it's more work the method will definitely yield the required result. I may well make the fixing bolt and bracket assembly first though, this will ensure exact alignment of the body to roof assembly when adding the filler.

It's getting there….
 

Simon

Flying Squad
JB Weld epoxy steel, mine came in two 1 oz tubes in a blister pack which I bought from Avery Knight and Bowler in Bath. It was quite expensive, I originally bought it to re-fix the steel bridge deck to the welded up girder bridge in the garden.
 

Simon

Flying Squad
I have now made up a roof fixing arrangement, captive/soldered 8BA nuts on brass strip bolted and then epoxied to the inside of the roof, "bolts" made by soldering cut bolt into each end of brass tube, (plus a washer under the bolt head) - just like Triang!

Roofix1.jpg

I have since attached the roof with the two bolts tightened up, with one side masked, a fifth pass of epoxy filler now made to bring the roof edge out to be parallel to the "straightened" side.

Roofix2.jpg

Only worry is that I forgot to put Silicon Grease on the masking tape before spreading the filler:rolleyes:

I'm sure it'll all come apart just the same, but I'll let the filler really cure first.

Simon
 

Simon

Flying Squad
Years without anything and then endless pictures of tedious bodged filling:rolleyes:

Well, I reckon it'll benefit from a sixth and final pass with the epoxy filler….

Andagain.jpg

Another upcoming issue is matching the roof profile to the cab profile at the joint. The problem being that on the cab master I have done the usual thing and in sanding the profile shape have effectively sanded down the "back edge" as well.

I seem to recall this is the result of some basic error in my sanding technique that I was probably told about in woodwork lessons of yore, although remembering our teacher perhaps not:))

Simon
 

Martin Field

Western Thunderer
Considering JB Weld is used by engine builders to repair broken castings and fix cracks, your use of it as a simple filler is certainly a use I've never seen it used for, but it will a) stick like the proverbial to an undergarment and b) be as fine a filler as you've used, if a little on the hard side to rub down.
I'd always use Milliput yellow/green for bulk filling but where fill needs to meet glue, you've done the right thing. Last time I used JB Weld it was repairing the magnesium sump of a Maserati 4 1/2 Litre V8! A job it did perfectly well where all other attempts to repair had failed.
 

Simon

Flying Squad
Considering JB Weld is used by engine builders to repair broken castings and fix cracks, your use of it as a simple filler is certainly a use I've never seen it used for, but it will a) stick like the proverbial to an undergarment and b) be as fine a filler as you've used, if a little on the hard side to rub down.
I'd always use Milliput yellow/green for bulk filling but where fill needs to meet glue, you've done the right thing. Last time I used JB Weld it was repairing the magnesium sump of a Maserati 4 1/2 Litre V8! A job it did perfectly well where all other attempts to repair had failed.

Crikey, I didn't realise it was as high tech as that!

I have just applied another bead of it to the slightly curved side and a small amount on the other side to fill a very slight gap along the lower edge, this is the sixth and hopefully final application of this filler.

You are right that it is quite hard to sand down, I have some pieces of very durable sanding belt that I have stuck to a piece of 2" X 1" timber with double sided tape to give myself a tough sanding block, which I use wet. I will finesse the shape of the roof with knife stopper and rub it all down with wet and dry before applying ribs etc.

Well, you all thought you were going to get away without seeing another picture of drying filler but I'm afraid I just couldn't resist it….

Railcars.jpg

I've perched the Hudswell Clark railcar on top to liven things up a bit.

In this shot you can see the problem I alluded to earlier where the cab roof profile doesn't match that of the roof section.

Simon
 

Martin Field

Western Thunderer
Ah, now you've put all that JB Weld on you won't be able to change the curvature of the roof sides. Which one is the more correct, the roof or the cab?
If you need to change the profile quickly now, you can use car body filler. It's cheap and quick and you can get the shape by making a template that fits the cab (assuming that's the correct one) and then after loading the roof with filler you draw the template along creating the radius and shape you need. It'll rub down easily and quickly too. The JB Weld will give it a good solid base.
I used to build show cars for the Germans and this was just one of the many dodges we used to hurry stuff along.
 

Simon

Flying Squad
It's the cab casting that is "wrong", but I like your idea of making a template and then drawing it across filler, I may well give that a bash. The "wrongness" results from over sanding the back edge of the cab when I made the pattern, as noted earlier.

Thanks for your ideas!

Simon
 

Martin Field

Western Thunderer
You're very welcome, Simon, but I note that the cab roof is generally sharper at the edges and therefore higher than the main roof at the edges, so either the main roof has to be "pulled out a little" or the cab has to be knocked back a bit. Do you mean you over sanded the central part of the back of the cab?
I think just as a gut feeling that the edges of the main roof need more "volume", but I don't have the drawings.
 

Simon

Flying Squad
A quick sand and a blow over with primer and I reckon the job's a good 'un.

Roofdone.jpg

I'm going to try and get the back edge of the cab casting to match next, you can see the mismatch in this picture.

Contemplating ideas, currently involving cling film and Ronseal epoxy wood filler, I'm not sure I'm brave enough to try tonight….
 

Dan Randall

Western Thunderer
I can't believe how well you've captured the look of the cab Simon - it looks spot on. :thumbs:

Will you be modifying the master to make a Class 121 after? ;)

Some driving trailers would look nice too......


Regards

Dan
 

Martin Field

Western Thunderer
Simon, you could do that in one hit with Milliput yellow/green. Honestly. It's perfectly mouldable with a spitty thumb, then sets hard after a night in a warm place, files down to shape and sands to a glass-like finish, ready for paint. Trust me, half the slot car patterns I do are modified or sculpted using Milliput and I can do a complete car master in (guess what?) 1/32nd scale in 2 days. Take this one. It started life as a hideously mis-shapen repop of a dodgy diecast and I must have put a 1/4 of a pack of Milli. on it, in one hit, then filed it back to an accurate shape. This pic shows the last application of Milliput to the roof and bonnet, which were both very sunken and generally mis-shapen. Some one shot epoxy putty I stole from VW's design studio in 1997. I still have and use it. Am I guilty? Nah!
004.JPG
This one shows the completely new front end in Milliput, repairs to the tail end and even repairs to air bubbles and damage.001.JPG
Just trying to save you time and hassle.

Cheers.
 

Simon

Flying Squad
Thanks Dan, whether I'll ever attempt another one is currently a bit of a moot point, but I would like a 121 in rail blue. It's all the frames around the windows that put me off - perhaps someone (else) could do an etch with matching window frames. I think that was Cynric's thought, I wish he was still with us to see this finally happening:(

Anyway, keeping positive and in a "for Gawd's sake get on with it" frame of mind, I have deployed cling film and Ronseal wood filler and reckon the result is not bad. I will fine fill to get the surface finish right, but the fit is pretty good, and the filler has also filled the slight gaps between roof and cab castings, resulting in a much more rigid structure with the roof bolted in place, this last feature has really cheered me up as it was quite "floppy" before.

Filler1.jpg

I have a slight issue on this position at both ends, in that the roof dome is higher than the aluminium roof towards its edge.
Filler2.jpg

Rather than fret too much over this, I may simply place a roof rib along the join (attached to the aluminium roof) to mask the join, which is otherwise bound to be obvious whatever I do.

Compared to prototype there wasn't a rib in this position, but I think I am going to deploy modellers licence as the benefit of losing the joint will outweigh any rib misplacement issue I think. Overall I'm quite chuffed with this now, it suddenly feels much more credible.

One looming "issue" is that the brass along the tops of the bodyside would be better filed back flush with the bodyside rather than being proud as now. I'm wondering whether if I support the sides with a long piece of corrugated cardboard set inside and between the sides I might then be able to file the brass back flush with the sides using one of my big files.

Anyway, that's enough for tonight!

Edit: I really ought to get some Milliput, that car looks great:thumbs:

Simon
 

Martin Field

Western Thunderer
The Milliput won't stick very well to the wood filler, Simon, but it's always worth having. I have 4 packs on the shelf so I never run out!
The discrepancy twixt body gutter and cab gutter must be annoying. I find if I can't put pressure on something I can gently (to avoid heat) disc it down with one of those rubber jobbies and a course disc or a cutting disc, but in that case I would use a fast sanding disc and just stroke it away. You ain't a real modelmaker till you've got rid of a bum steer or two without making them worse<G> Good luck.

Martin

Edited to say:- There are a lot of good quality, accurate 1/32nd scale car bodies around with good glazing and wheel inserts for ally wheels with decent tyres that would smarten any G1 layout of the 50s/60s/70s. I just did a Mk 3 Capri and there are sports cars like the Lotus Elite, AC Ace, A-H Sprite, etc. And I have a Bedford Big S cab and a Thames Trader in the offing. My chum does SAABS and a very nice Sunbeam 90 as well as Land Rovers and a Rover P6(police car?)
 
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Yorkshire Dave

Western Thunderer
One looming "issue" is that the brass along the tops of the bodyside would be better filed back flush with the bodyside rather than being proud as now. I'm wondering whether if I support the sides with a long piece of corrugated cardboard set inside and between the sides I might then be able to file the brass back flush with the sides using one of my big files.

One idea is to stick a sacrificial strip of styrene to the bodyside under the brass with double sided tape, support from the inside with a block of wood (I think corrugated card will have to much give) then attack with a large first cut file. This way you can be fairly rough until the double sided tape appears. At which point you can use a second cut or finer file followed by emery paper to tidy up.
 
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