Garden Railway Forum

Hi all, ive just tested a Melrin Midas which i brought of ebay recently and i am glad to say it steams very well. It takes about 6-7 minuets to boil but i think this is normal and i cant get it above 20 on the pressure gauge so i assume thats the blow of pressure as the safety valve lets a little steam out. The loco runs very smoothely and quietly and seems to be very steady a little steam is escaping from around the cylinder area but not much and i think this is fairly normal. I plan to re paint it and possibly add a crank to the regulator for radio control.
Any advice on how to run these locos would be greatly appreciated and i have a few questions:

How much water does it need (i know there is a water glass but im not entierly sure how much to put in?)

How do i empty the water from the boiler (is it just through the safety valve?)

How much do i need to turn up the gas?

How long will the engine run for? (only ran it for 5 mins)

How can i re paint it? (will i need primer? will i need to remove old paint?)

thanks in advance
Joe

Fill it up to about 2/3rds of the way up the glass.
I use a syringe and a length of plastic tube to empty the boiler after a run, sucked out via the safety valve hole.
Gas is a funny one, you will need to get used to it as they all vary. One comment that is often heard at meetings where newbies are running is "turn the gas down"
The loco should run for longer than 5 minutes, I get around 25 mins from my Merlin.
If you are going to repaint then ideally remove the paint, if you cant do that then sand the old paint as flat as possible. You will need to prime bare brass with etch primer.

Ok cheers, how do i remove the paint? one thing ive noticed is its a bit difficult to light as it sometimes pops but doesnt light but other times it lights but you dont realise until theres smoke coming from the chimeny, you can hear it alright when its got some pressure though

Paint stipper such as nitromors but it is REALLY, REALLY, REALLY nasty stuff. Or thinners (available from any motor factors.). Brake fluid can be used as well.

With all the above make sure you wash the body thoroughly afterwards.

Heres a picture, i do think it needs a new paint job but it does look nice :


another quick question, how long does it roughly take to fill the gas tank as i dont really want to be over filling it?

cheers
Joe

Keep filling until the gas starts squirting out from around the valve.

Well just tested it again and after a while it was steaming nicely and the gas was lasting much longer but i think the gas jet may be a little blocked because i cant hear the gas flowing through as good as i think it should be and it seems to take a while to gain pressure, so will clean that tomorrow, ive noticed that the loco doesnt really need much regulator to get it moving on the tracks which is a good thing

Removing paint - Nitromors is proven but really nasty. Brake fluid is crap. I use BioStrip - effective especially when in a warm environment eg by a radiator or fire, and completely non toxic [no fumes, no skin issues] - unless you swallow it.

Big Jim:108202 wrote:Paint stipper such as nitromors but it is REALLY, REALLY, REALLY nasty stuff.

In 2006 the selling of paint strippers that included dichloromethane (also known as methylene chloride) was prohibited, so Nitromors is not as "nasty" as it used to be. It also is not as effective as it used to be.

Ahhh, that would explain why the 5 gallon drum I found at a farm sale 15 years ago works and the stuff I bought before Xmas doesn't.

Well ive got the body of today to have a proper look and the boiler, valve gear etc look to be in very good condition however while getting the gas jet out to check that was ok i noticed that gas was leaking from the gas control nob, any idea why and how i can fix it and also if there is a way of completely unscrewing the gas nob?

I have tried to wash out the gas tank as best i can but i presume the control nob needs a new seal of some description

cheers
Joe

Big Jim:108215 wrote:Ahhh, that would explain why the 5 gallon drum I found at a farm sale 15 years ago works and the stuff I bought before Xmas doesn't.

Same applies to a lot of products now unfortunately, creosote, oil based gloss paint etc, the old traditional stuff which works has been banned, the modern environmentally friendly Euro-crap doesn't.

When I started to build my brass loco body I wondered why I suddenly couldn't solder any more. Then I realised it was the awful lead-free solder I'd bought, it just wouldn't flow. I managed to find a large reel (enough to see me out !) of proper 60/40 lead/tin solder on eBay and lo-and-behold I could solder again !

Brian

Old fashioned creosote can still be bought if you can find any and can prove a 'Legitimate use'. Rust removers such as jenolite have gone the same way, ie crap.

Well ive got the body of today to have a proper look and the boiler, valve gear etc look to be in very good condition however while getting the gas jet out to check that was ok i noticed that gas was leaking from the gas control nob, any idea why and how i can fix it and also if there is a way of completely unscrewing the gas nob so i can remove the gas tank from the cab?

I have tried to wash out the gas tank as best i can but i presume the control nob needs a new seal of some description

cheers
Joe

On my Merlin the gas tank was secured to the cab roof and was removed buy un bolting the roof and removing the cable ties that held the white gas pipe on.

As to changing the control valve seals, try unscrewing the knob and see if it comes out of the body, it may be just an O ring seal.

The best way to check for leaks is to fill the tank and cover liberally with soapy water and see where the bubbles issue from, or stick in a basin of water.

Thanks jim, i will try unscrewing the control nob as that stops me removing the gas tank from the cab

The knobs are just a screw fit infact the one on my Zillertal is loose and I need to put some thread lock on. The regulator knob as a pin through it which needs removing first.

Well i got the white nob of and set up the burner out of the engine and it worked well, i seem to have sorted the gas flow, it still is leaking from the gas control nob but not to badly i will put the loco back together and give it a steam tomorrow as i tried today but it wouldn't light properly probably because i hadn't secured the burner and put the cab and gas tank back on fully.

Well today i tested it properly and after getting the gas jet out to unblock it again it runs really really well with a large smoke plume, really pleased with my purchase i will run it on the rails next week i just need a new gas filler valve for it

Just ordered a syringe to empty the brass boiler but unfortunately it has got a little water in it for now but the syringe should come in the post in 4 Days