A Chequered Chieftain at #10

[Richard Goodwin]

Vince....there seems to be a few types on Amazon, link below:
https://www.amazon.co.uk/s?k=jbweld+ori ... b_ss_i_1_6

Could you have a look please and let me know which one? A link would be good....VMT

[Vince Cutajar]

https://www.amazon.co.uk/JB-WELD-MAC826 ... 144&sr=8-2

Vince

[Stephen White]

Richard, I used to use the two part epoxies but I've recently started using UV activated glue and it's much better (stronger and adheres better). The only limitation is that the glue obviously has to be visible to the UV light source, so fillets and butt joints are fine but you'd struggle with gluing flat plates surface to surface. I've used it on the hull front where I changed the profile. I've done a piece on UV glue here on the Forum, somewhere.

[Richard Goodwin]

Many thanks Vince. I thought that was the the one but just wanted to be sure.

Stephen, thanks for your reply. I've seen your posts on that subject but as you say, the UV wouldn't get through for this particular application I'm thinking of. Thank you for replying though.

Regards to both and hope your keeping safe and well.

[Richard Goodwin]

There was I sitting in the garden soaking up the rays; one eye on my G&T, the other watching the etch primer drying when I suddenly had a eureka moment. I had been thinking about how I was going to make my own thin braided wire and still keep the definition of the braid when I painted it, then the penny dropped as to how.

I was going to be using 1mm diameter malleable wire as the former and 2mm solder wicking braid as the braid; the trick however, would be to get the wire in the braid. After cutting a length of braid and and ensuring it wasn't twisted anywhere along its length, the first 25mm was opened up using a scriber whereupon a stiff 1mm rod with the end rounded was then inserted and gradually worked up through the flattened braid; it takes a little patience but it can be done.

Now for the painting and the need to keep this definition...

Give the braid a thin coat of etch primer. This will fill up any gaps but don't worry, leave it for 5 mins to dry and then squish up the braid along its length..

This has the effect of knocking off all the etch between the wires and brings back the depth of definition as seen below..

Next, apply for primer basecoat and again squish up the braid after 5 mins. The example below was done in white since that will be my base for the Berlin Camo scheme..

you can now apply some drops of superglue to hold the braid in place if needed, after which, apply the top coat but this time, don't squish the braid. The example below is early Berlin Blue Grey.

I believe the picture above clearly shows a good definition of the braid with the final diameter of the wire being 1.5 approx and will prove useful for the Chieftain! I've certainly seen braided wire on the turret cheeks going to the smoke dischargers as well as around the exhaust box.

[John Clarke]

Nice touch Richard

[Vince Cutajar]

That's a great idea of using the desoldering braid.

Vince

[Richard Goodwin]

Sorted the rear towing lugs today. The supplied item looks like this.....

As you can see, it is one continuous angle down from the eye to the angle plate and stops there. However, when you look at an original, it is very different. Note the sharp angle down from the eye till after the hook (red arrow) whereby the angle shallows out and that the foot of the lug goes under the angle plate (blue arrow). Also note the hole allowing the lug to avoid the sticky out part of the angle plate (green arrow).

real towing lug.jpg (171.58 KiB) Viewed 2422 times

Now I don't know for certain but an educated guess would be that the initial steeper angle ensures the hook stays more upright to assist with installing a cable. The picture below shows what I mean...

So the intention is to try and reproduce the original; one problem though, I don't have any drawings and there's not much chance to get out to a tank to make some measurements so its going to have to be best guess so a template is in order starting with the shape of the supplied lug....

Next I draw my best guess line from the eye using a couple of measurements I took in relation to how far the back of the hook would need to extend beyond the original and then after the hook, changed the angle to run parallel with the supplied lug....

I used a profile gauge to get the angle of the lug relative to the angle plate and drew the rear of the lug....

then finally estimating the foot underneath which i believed ran parallel to the ground.....

Clearly some fine tuning would be required once the piece was cut out. Now the supplied item was in 8mm but as I said previously, I'll be doing mine in 6mm. After cutting out and with some adjust on test filing, i was happy with the result..

Using this as a template, another was produced with the final installed look being as follows....

DSCF0986-1.jpg (142.89 KiB) Viewed 2422 times

Although I'm quite happy with the result, if I had to do it again, I would make the initial angle steeper and in that way, I could reduce it till absolute spot on. This was a best guess but a good result methinks.

[Richard Goodwin]

Finally, a well known DIY store has delivered my mdf and ply so I can now continue with the 'dreaded' exhaust box!

Onward and upward cutting the front plate to reduce it down by 30mm. Am going to do this again with the router so the same process used before to cut the sides will be repeated except this time the surround will be in 6mm mdf since the front plate is 6mm!

Double sided tape has been used again to help keep the work in position and hold the pieces in place once the cut has been made...

Cut lines marked and guides installed ensuring that the calculation of distances was taken into account as previously demonstrated! With that the cut was made; again using 0.25mm cuts and hoovering up after each pass....

The next thing to consider was the side pieces. Now Stephen has kindly supplied a Mk5 production drawing of the box which shows the sides to have a 5 degree angle from the vertical which makes it perpendicular to the ground when mounted on the rear plate. This would mean that the main rear plate was 85 degrees from the horizontal! Whilst there is talk of a possible alternative build standard to this, as far as 03 EB 20 is concerned, the photographic evidence clearly shows her exhaust box being upright...

However, before cutting the sides, best check the model itself first!

So it differs by about 2 degrees; now that may not seem much but when you draw that angle and an 85 degree angle on the sides of the plate, it makes a difference of around 3.5mm!

SO before I try and adjust the rear plate, i thought it best to install the glacis plate, the turret tray and the rear deck to see how much wiggle room I had in the adjustment. Now I wasn't expecting a lot since I had previously done this when I was working on the angle plate.....

There was very little room for any more adjustment so again the final angle was measured...

So it looks like my cutting angle will be 83.2 degrees from the horizontal or putting it another way, 6.8 degrees from the vertical. If I get that, then my exhaust box should be perpendicular to the ground. So tomorrow will be the big cutting day; wish me luck!

[Steve Norris]

Hi Richard
This is going to be a very accurate exhaust box. Love the set up you have for creating the rebates, very inventive.
As for the exhaust box angle, I just used the mark 1 eyeball and it turned out near enough.
Looking forward to seeing more of your build.
Regards
Steve

[John Clarke]

Looking good Richard,

I think I got one of those prototype thingy exhaust boxes, the one's that come virtually symmetrical.

You know the one, the one that fitted to the mysterious Mk4.

Shazbat!

But if I cut carefully.......

SAM_2447.JPG (169.56 KiB) Viewed 2356 times

[Richard Goodwin]

Gents, thanks for your comments.

Unfortunately Steve, I can no longer rely on the Mk1 eyeball even as an estimate hence the need to use various tools and gauges to check and align. I wish i could, it would save a lot of aggravation Because of the setup I'm using, its unlikely that I will be able to cut to that exact angle although it will be Mk1 eyeball close, the jig I'm using will however, ensure that both sides are cut the same.

John, fabulous job on the detail mate and has certainly given me some idea's. I do enjoy reading your blogs; great sense of humour. It's a shame that not many of us are showing our work but hey ho. I'm fortunate to have got the benefit of those that have gone before me and learnt from the techniques etc they have used which for me, is what this forum is all about! I in turn try and pass that knowledge on with my own twists which is why my blogs tend to be detailed. Hopefully, the time taken to do that is worthwhile! One last point, every time I look at this box, I see something extra myself and wonder when will it stop

Btw, the angle gauge is part of my anti mirror defence

[John Clarke]

Totally agree Richard, The more blogs, the more ideas, the better it gets.

My general guide is the rule of thumb, having big thumbs, trying to scale the un-scale-able has become a bit of a mare.

But on "reflection" it's a nice day, and I'm going to tear the exhaust box off "again" and try and straighten it up.

and that's a contradictory statement if I ever heard one. But it's my "anti anti" mirror defense

I think Lock Down is sending me doolally.

Now where did I put the grinder?

[Richard Goodwin]

Time to chop the angle on the side plates! Reconfigured the side plate jig to hold the work securely whilst cutting....

Note the black lines I've added to assist with alignment when refitting of the guide! Now I'm going to admit a mistake I made here to demonstrate the possible effects of not using double sided tape to help hold the work securely. After taking the picture, I should have removed the work from the surround and added the tape but instead installed the guides. I suddenly remembered that I hadn't done it but thought that the lower guide that was virtually covering the work would hold it in place! WRONG

The picture below shows the two cut pieces together for comparison....

Look at the left piece, you can see that the cut isn't straight and that there is a couple of gouges taken out of it. I was very lucky it wasn't worse, so let that be a lesson to all!!
Anyway, now for the top plate. Using the jig previously used for the front plate, the surround was reconfigured for the plate; note the use of double sided tape

The next picture shows the cut completed and both parts of the plate are held in position by the tape! Just making the point here!!

The box was then constructed and the top and bottom plates filed at an angle to match the side plates. The box was then installed on the rear plate of the tank and the angle checked! Now I would've been happy with plus or minus half a degree bearing in mind the method used and the use of mdf for guide rails. I was quite surprised at the end result.....

Exhaust holes next up......they are getting moved!

[Vince Cutajar]

Great result.

Vince