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WW1 Thornycroft restoration

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A question to the master painter. Why such a small brush when the flat areas are so large? Did you keep rotating the tank so that the flat panels were always horizontal as there doesn't seem to be a single run from any of the rivets! A general question too. What are the drill holes for in the side panels?

 

Barry.

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]A question to the master painter. Why such a small brush when the flat areas are so large? Did you keep rotating the tank so that the flat panels were always horizontal as there doesn't seem to be a single run from any of the rivets! A general question too. What are the drill holes for in the side panels?

 

Barry.

 

[/i]Well, for jobs like that, I would use either 1 1/2" and/or 2" brushes. No special tricks and I expect the Professionals would say that I have got it all wrong - but it seems to work for me! With that seam, it was a smaller brush being used there as I wanted to make sure that the paint really reached into the joint.

 

And yes, I do prefer to paint on a horizontal surface so I rotate the object where ever possible so that I can paint on a horizontal surface - that does obviously help eliminate any runs.

 

There is an "Instruction to Drivers" enamel plate fixed to the side panel of the tank and that side panel was pre-drilled and tapped to take that plate before assembly. When the painting has been completed, the plate can be finally screwed to it.

 

Tony

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As always excellent innovative work from the Gosling gestalt :thumbsup:

 

Will you be injecting a sealer inside the double skinned end of the tank to prevent internal rusting?

 

Bernard

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In the same vein, will you be using a chemical liner inside the tank to protect the metal from modern fuel?

 

Inspiring work as always

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If lining a tank, I can recommend POR15. It was used to line my M151A2 tank in 2007/8, and is still performing as per manufacturers intention (the filler neck is large enough and the tank small enough to see a good deal of the interior).

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We won't fill between the end plates as once the oxygen iis used up, they will stop corroding.

 

I'm not planning to line the interior at the moment but I should be pleased to hear some thoughts both for and against. What are the actual issues with modern fuel and what might be going on inside the tank? I don't think of ethanol as being that aggressive towards metals, unless you know different!

 

Steve :)

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Steve

 

Given what you have told us about how surprised you have been at how quick the steel for that tank has rusted, I would be concerned about condensation induced internal rust.

 

PQR-15 or equivalent should mean you never have any problems with rust contamination.

 

The problem I had with my Kettenkrad is that with age and probably vibration, the rust turns into a powder finer than talcum, it then got straight through the fuel filter (like the thing did not exist) and clogged up the carby. Caused me quite a bit of grief. Which is why I used the Aussie equivalent of PQR-15. There is a process involved and you have to be careful not to get it on anything you don't want it on, including you as you will not be rid of it till your skin sheds at that location (I heeded the warnings and took due care).

 

Regards

Doug

 

We won't fill between the end plates as once the oxygen iis used up, they will stop corroding.

 

I'm not planning to line the interior at the moment but I should be pleased to hear some thoughts both for and against. What are the actual issues with modern fuel and what might be going on inside the tank? I don't think of ethanol as being that aggressive towards metals, unless you know different!

 

Steve :)

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We won't fill between the end plates as once the oxygen iis used up, they will stop corroding.

 

Steve :)

 

I learn something from every post, but that one's so obvious I should have known! :embarrassed:

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It's not so much the fuel that you need to worry about, as previously said it's the condensation and water content of the fuel that is the issue. I know with my MUTT tank the tank the decision was made to line it as it had been repaired and was a bit thin in places. Our CVRT has an old (unlined) Bedford lorry tank installed, and that is forever putting rust into the fuel filter.

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someone sent me this I'm not that bright.

 

"Ethanol becomes corrosive once it starts to oxidize. This will cause corrosive acid to form. Secondly algae growth formation is caused by water contamination.

 

Ethanol is already water soluble so if not addressed properly it could cause major issues with any metal in a vehicle's fuel system or fuel pumps."

 

And this

 

"Ethanol itself is not particularly corrosive. When the oil companies first started blending ethanol in fuel, it corroded some rubber and plastic gaskets on some cars and equipment. Manufacturers figured it out and substituted new materials. The unlucky consumers whose equipment was ruined or whose fuel systems had to be replaced just took it on the chin as per usual with most government programs.But that wasn’t the end of it.

Ethanol attracts water. When the two get together, they create the perfect environment to grow a type of bacteria called acetobacter. After getting drunk on their EPA-sponsored kegger in your gas tank, the acetobacter excrete acetic acid. And acetic acid is very corrosive.

If you’re refilling your gas tank every week or two, acetobacter don’t have time to grow a sufficient size colony to damage metal parts in your fuel system. But if your fuel sits for longer periods of time these microorganisms continue to multiply until your gas tank contains damaging levels of acetic acid."

 

No I don't really understand it either other than best advice is line fuel tanks.

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When the oil companies first started blending ethanol in fuel, it corroded some rubber and plastic gaskets on some cars and equipment. Manufacturers figured it out and substituted new materials. The unlucky consumers whose equipment was ruined or whose fuel systems had to be replaced just took it on the chin as per usual with most government programs.

 

I think a lot of this "information" comes from the US and might not be UK-relevant.

 

If you are worried about ethanol then avoid the E10 petrol. BP Ultimate, for example, contains only dead dinosaurs.

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Thank you for all of that gentlemen. Lots of food for thought there. I must take a look inside the Dennis tank and see what is going on there as that is unlined.

 

A while back, Barry very kindly 3d-printed the patterns for the silencer ends for us.

 

DSCN3807.JPG

 

DSCN3809.JPG

 

They are super. However, the process produces a textured surface which will make it very difficult to slide the sand out so he recommended painting them with a two-part epoxy called, not surprisingly, 'Pattern Coat'. He sent me a sample which I used for the first coat. You have to be very quick with the stuff as it is like trying to paint with a jelly after about five minutes but it does fill the surface very well. I carefully rubbed it back, (a most tedious job!) before applying a second coat and then rubbed that back as well. The surface came out very smooth and I am sure they will be fine.

 

DSCN6825.JPG

 

DSCN6826.JPG

 

DSCN6827.JPG

 

Dad dropped them off at the foundry this week so that is another pattern ticked off the list!

 

Many thanks, Barry.

 

Steve :)

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The carburettor has been occupying my bench for ages so I thought it time to sort it out and get it fitted so that it would be out of the way! The manual has a very useful section of the bronze, updraft Solex with barrel throttle with which they were originally fitted.

 

Carb Drg.JPG

 

After about five years of looking, in other words, twenty three years ago, I managed to track this one down which is almost right but of the 1923 pattern which has a slightly different idle arrangement. Conveniently, the manual quotes the jet and choke sizes and the dealer managed to match the jets for me but didn't have a 28mm choke tube.

 

DSCN6828.JPG

 

DSCN6829.JPG

 

I started pulling it apart and fortunately, this was fairly straightforward.

 

DSCN6830.JPG

 

DSCN6831.JPG

 

DSCN6833.JPG

 

Then the choke tube. This came out OK but has a hole and slot in the side which does not line up with anything. It has also been filed on the outside diameter so I think it has had a hard life and probably come out of something else as the dealer knew that I wouldn't be using it. It has a 22mm throat.

 

DSCN6835.JPG

 

DSCN6837.JPG

 

DSCN6839.JPG

 

Then the end plates on the barrel. These appeared to be simply pushed in so I tapped the end of the throttle barrel with a mallet until one came out.

 

DSCN6840.JPG

 

Oh.....

 

DSCN6842.JPG

 

So that was what the screw was for!

 

DSCN6843.JPG

 

I then attacked the screws with heat and an impact driver. I twisted the end off twice but eventually got one out.

 

DSCN6846.JPG

 

DSCN6848.JPG

 

It is metric, 5x0.75mm for which, of course, I don't have a tap or die. A quick call to Tracy Tools had them in the post the next day and I cleaned it and the hole up .

 

DSCN6849.JPG

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The main jet had a polish.

 

DSCN6855.JPG

 

Then the throttle and end caps. I couldn't wire brush them as it took off the nickle so I was left with just Brasso as I couldn't find a solvent that would touch the muck on the outside. I dressed the damaged cover with a needle file and then polished the ends flat with fine emery paper on the surface plate so that the throttle would have a reasonable chance of sealing against them.

 

DSCN6852.JPG

 

I drilled out the screw which I failed to remove earlier and then ran the tap through very carefully. This was successful, I am pleased to report.

 

DSCN6853.JPG

 

All of the original bits, ready to fit. Cleaning the main castings was exceptionally painful as I could not find a solvent which would shift the muck and resorted to hand scraping and Brasso. What should I use to clean a carburettor?

 

DSCN6856.JPG

 

Now, on to the bits I had to make. The venturi should have a 28mm throat, according to the manual. However, I was surprised to find that the diameter through the throttle was already 28mm so that there would be no divergence until after the throttle. I was fortunate to be able to borrow a Solex MOV40, which is a later incarnation of mine, and was interested to find that the venturi in that one also had no divergence. I find this puzzling but it gave me the confidence to turn one up.

 

DSCN6866.JPG

 

DSCN6868.JPG

 

DSCN6857.JPG

 

DSCN6858.JPG

 

Then I turned up a replacement screw to secure the end cover.

 

DSCN6860.JPG

 

I fitted the covers using the mill and the lathe as presses in order to make sure that I put them in squarely. This worked well and I managed to remove almost all of the end float in the throttle barrel without it binding.

 

DSCN6862.JPG

 

DSCN6863.JPG

 

DSCN6865.JPG

 

Clean up the banjo and final assembly and it is ready to fit.

 

DSCN6871.JPG

 

DSCN6872.JPG

 

Something to take to Devon the next time I am heading that way. Now it is back to pattern making.

 

Steve :)

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Steve,

 

What made you suspect that it was a M5 x 0.75 screw? It would have been so easy to think it was the standard M5 x 0.8 pitch. It would need a very sharp eye to spot the difference. Very impressed!

 

Barry.

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What made you suspect that it was a M5 x 0.75 screw? It would have been so easy to think it was the standard M5 x 0.8 pitch. It would need a very sharp eye to spot the difference. Very impressed!

 

I am pretty sure that we have an M5 x 0.75 thread tap in the fire engine garage, bought especially for the Zenith on that vehicle.

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I don't have a suitable thread gauge as we are not geared up for metric! I took my glasses off, looked closely and then counted ten threads against a 6" rule which does have a metric scale. I tried to make it 0.8mm pitch but it just didn't work so I settled for 0.75. I did hold the tap against the screw first, though, just to make sure.

 

Macro vision is about the only advantage of short-sightedness!

 

Steve :)

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I don't have a suitable thread gauge as we are not geared up for metric! I took my glasses off, looked closely and then counted ten threads against a 6" rule which does have a metric scale. I tried to make it 0.8mm pitch but it just didn't work so I settled for 0.75. I did hold the tap against the screw first, though, just to make sure.

 

Macro vision is about the only advantage of short-sightedness!

 

Steve :)

 

Nice to meet up & chat Steve down at shuttleworth the weekend

 

 

The 2 subsidy trucks there were great...

 

Did you see the 1920 Albion Charabanc...?

 

 

They let me have a go at starting it...

 

Quite easy...and with no modern gimmicks on it...

Edited by flandersflyer

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The main jet had a polish.

 

attachment.php?attachmentid=129363&stc=1

 

Then the throttle and end caps. I couldn't wire brush them as it took off the nickle so I was left with just Brasso as I couldn't find a solvent that would touch the muck on the outside. I dressed the damaged cover with a needle file and then polished the ends flat with fine emery paper on the surface plate so that the throttle would have a reasonable chance of sealing against them.

 

attachment.php?attachmentid=129361&stc=1

 

I drilled out the screw which I failed to remove earlier and then ran the tap through very carefully. This was successful, I am pleased to report.

 

attachment.php?attachmentid=129362&stc=1

 

All of the original bits, ready to fit. Cleaning the main castings was exceptionally painful as I could not find a solvent which would shift the muck and resorted to hand scraping and Brasso. What should I use to clean a carburettor?

 

attachment.php?attachmentid=129364&stc=1

 

Now, on to the bits I had to make. The venturi should have a 28mm throat, according to the manual. However, I was surprised to find that the diameter through the throttle was already 28mm so that there would be no divergence until after the throttle. I was fortunate to be able to borrow a Solex MOV40, which is a later incarnation of mine, and was interested to find that the venturi in that one also had no divergence. I find this puzzling but it gave me the confidence to turn one up.

 

attachment.php?attachmentid=129371&stc=1

 

attachment.php?attachmentid=129372&stc=1

 

attachment.php?attachmentid=129365&stc=1

 

attachment.php?attachmentid=129366&stc=1

 

Then I turned up a replacement screw to secure the end cover.

 

attachment.php?attachmentid=129367&stc=1

 

I fitted the covers using the mill and the lathe as presses in order to make sure that I put them in squarely. This worked well and I managed to remove almost all of the end float in the throttle barrel without it binding.

 

attachment.php?attachmentid=129368&stc=1

 

attachment.php?attachmentid=129369&stc=1

 

attachment.php?attachmentid=129370&stc=1

 

Clean up the banjo and final assembly and it is ready to fit.

 

attachment.php?attachmentid=129373&stc=1

 

attachment.php?attachmentid=129374&stc=1

 

Something to take to Devon the next time I am heading that way. Now it is back to pattern making.

 

Steve :)

 

Carb cleaner

 

It's quite aggressive stuff so don't get it near painted surfaces or rubber diaphragm/seals etc...

 

 

Failing that then throw it in a tub of Tol...

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Carb cleaner

 

It's quite aggressive stuff so don't get it near painted surfaces or rubber diaphragm/seals etc...

 

 

Failing that then throw it in a tub of Tol...

 

I've seen Amal carbs that have been cleaned in an ultrasonic cleaner and they looked as clean inside and outside as new ones:-

 

https://en.wikipedia.org/wiki/Ultrasonic_cleaning

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Ultrasonic cleaners are the best method. Lot of carb and gearbox specialists use them. Also some tool hire places. Probably get a cheap one on eBay but depends on your usage.

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A few odds and ends going on this week. I have turned up two more carburettor choke tubes of 27 and 26mm bore so I will have something to play with when we start the engine for the first time.

 

DSCN6888.JPG

 

It was nice to meet up with several forum friends at Old Warden Steam Rally the other day. I was pleased to see that John Marshall has the same size carburettor on his Thornycroft as we have. It gives one confidence!

 

I have just bought some 'Wynns Carburettor Cleaner' in Halfords. I hadn't thought that there might be such a thing until FlandersFlyer mentioned it a few days ago. There is always something new to learn!

 

More posts shortly.

 

Steve :)

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Father has been to the foundry this week and picked up the latest castings. These are the silencer ends for which the patterns were so kindly printed by Barry and also the the top water pipe for which I am indebted to John for the loan of his original to use as a pattern.

 

DSCN4222.jpg

 

The moulder was very pleased with the finish on the pattern due to the 'Patterncoat' paint as it made it much easier to extract them from the sand. It was painful to rub back but obviously well worth doing.

 

DSCN4223.jpg

 

DSCN4226.jpg

 

DSCN4228.jpg

 

DSCN4230.jpg

 

DSCN4231.JPG

 

Dad now has some more homework!

 

Steve :)

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