automatic drain cocks

[jamienwr]

Hi all,
I'm just wondering if there is anywhere that sells automatic drain cocks for a 5 inch gauge Polly 3?
There is a slight problem with my engine as one of the drain cock holes has been opened up to 1/4 inch and the rest are standard size (1BA thread, but I'm not sure how many millimeter's or inches that is)
Hope you can help
Thanks
Jamie

[lordsimon]

hello there

depending on what type of cylinder you have you could always if theres enough room open the hole up a little more tap it

say you have 1/4 think between the bore and the out side of the cylinder.

get a piece of metal the same as the cylinder to make a plug

you want 1/8th over hang as you will need to grip it
turn it down to the size to die the out side but before die drill and tap the 3/8 piece down a 1/4 to 1 ba so you have a 1/8 left

now with the split die open up so you get a tightish thread with some loctite

thread in the 1/4 with the 1ba taped bit on the inside of the cylinder

so now file of or mill the 1/8 over hang till you get to the thread which you may need to just run the 1 ba tap back through

so what you should get is a nice tight plug that will not come out with your 1ba hole still there for the right drain plug

this is what i may do if i had that problem as it save trying to drill and tap all the other holes

simon

hope this makes sence i cant spell lol

[jamienwr]

CHeers simion, I did understand that (don't know how because I'm new to model engineering),
I will try and manufactur the parts myself but I doubt i'll be able to do a good job myself lol

[waggy]

Jamie,

I'm sure you will do a good job, have faith in yourself!

Now, make like a pair of curtains, pull yourself together and do it!

There is always plenty of advice here, don't forget that.

Regards,

Waggy.

[steam4ian]

G'day Waggy et al.
I am intrigued by the idea of automatic drain cocks.
How do they work?
Can I see a sketch without infringing on copyright?

Regards,
Ian

[baggo]

Hi Ian,

have a look at:
modeleng.proboards20.com/index.cgi?board=Images&action=display&thread=1168277143

I've got a copy of an article by Bob Thomas on these that I can send you if you are interested.

John