Greetings -

Junior is pretty much done, however....

I cannot get a seal at the fitting to the gauge. The mating surfaces look good and I replaced the teflon seal at the gauge. Pulled and reinstalled the assembly several times, trying different schemes, to get it to seal, all to no avail. Have applied more force to the nut than usual, and looking at the seal it seems to be mating well to the gauge fitting.

It's a steam leak coming out of the rear of the fitting nut at the rear of the gauge where the copper tube enters the nut. Starts leaking well before 1 bar.

Any ideas welcome.

Looks like I found the problem. There was a hairline crack at the fitting to the gauge. Tried silver brazing it, but without much luck. Will give it one more go and if still unsuccessful will bite the bullet and order a new tube. Dang thing is $65.

Often I find that taking photos and enlarging them through cropping on my computer shows me details I hadn't seen before. Glad you found this one.

Hello:

cuppajoe wrote: ... hairline crack at the fitting to the gauge.
... will bite the bullet and order a new tube. Dang thing is $65.

IMHO, overpriced.
Like most (if not all) Cimbali parts.

If I am not mistaken, these tubes have a Serto brand fitting soldered each end and the nuts press them against the male ends to seal, metal on metal.

If I were in your shoes and since the problem seems to be in the tube itself, I'd carefully recover the Serto fittings at each end of the old tube by desoldering them and then re-solder/weld them with silver solder (the stuff used in air conditioning piping) to a new piece of tubing which you will have to make yourself from a length with the right dimensions (ie: OD/ID).

All you need (besides some practise) is a Mapp torch, the solder and the powder/paste flux.

Hope this helps.

Cheers,

CIV

Edit: spelling due to lack of coordination at certain speed. =-/

Agreed, $65 does seem a bit much of what it is.

This is what I've been trying to fix the crack with. Enough horsepower to do the tube replacement? And much difference between the flux in the kit compared to the powdered product you recommended?


Thanks

Hello:

cuppajoe wrote:Agreed, $65 does seem a bit much of what it is.

Quite so ...
It's my pet peeve with Cimbali.

cuppajoe wrote: This is what I've been trying to fix the crack with.

Maybe OK, don't know about the flame.
It's a matter of practise, practise and eventually getting the hand of it.

Check these guys out:
http://www.youtube.com/watch?v=lxXrw1hENb8
http://www.youtube.com/watch?v=kIKQ-FL96uU
Soldering with silver for begginers well explained.

Try to do some on a scrap piece of pipe to see if the flame is high enough.

cuppajoe wrote: Enough horsepower to do the tube replacement?

Can't say from here, it does seems a bit underpowered.
Silver soldering needs good heat, I use a Worthington Mapp/Pro gas can.
The copper tubing has to glow cherry red.

cuppajoe wrote: And much difference between the flux in the kit compared to the powdered product you recommended?

This flux thing is 'the' most essential item (besides proper heat) to get correct.
It is related to the material to solder and the solder itself.

If you do not get that right (been there a lot) it can be quite frustrating.
Spent days trying to silver solder with the wrong flux ... 8^/-
Very frustrating.

I recommend practising a lot.

Pieces to join must be squeaky clean for the soldering process to work properly.
Do post a couple of photos of the ends of the pipe with the nuts moved back, would like to check the fittings are Serto.

Cheers,

CIV

That torch is butane, which should heat to 1970C in air. MAPP should heat to 2010C in air. They're pretty close. I like the guideline to heat the copper tubing until it glows cherry red.

Hello:

drgary wrote: That torch is butane, which should heat to 1970C ...
MAPP should heat to 2010C in air ...

Sounds about right ...

But the thing is the 'rate' at which the torch used with any of these two gases can heat the piece to solder.

If the piece is too large for this 'rate' (ie: loses heat faster than what the torch can give it) things won't work well.

One trick is to use a 'bed' of those special bricks/tiles used for fireplaces and such, they will reflect heat to the piece being heated.

drgary wrote: I like the guideline to heat the copper tubing until it glows cherry red.

That's about the right temperature.
But not too much above that colour, as some solders and fluxes will misbehave if the temperature is too high.

Cheers,

CIV

Thanks guys, most helpful.

The one fitting is marked Serto, the other end is completely different.



In any case, it's the fitting itself that's damaged, so looks like time to bite the bullet. The damaged end appears to have been worked on before.

Also hit it with the torch again and not getting anywhere near hot enough. Certainly not close to 'cherry red'.

Hello:

cuppajoe wrote: The one fitting is marked Serto, the other end is completely different.

It looks different but methinks the fittings may be both Serto albeit one of them with a different nut.

cuppajoe wrote: ... the fitting itself that's damaged ...

Quite so.
Severely mistreated.

cuppajoe wrote: ... looks like time to bite the bullet.

Hmmm ...
Hold on a bit, there's plenty hope yet.

cuppajoe wrote: ... not getting anywhere near hot enough. Certainly not close to 'cherry red'.

You need a good torch, won't get anywhere with what you are using now.

Get yourself a Bernzomatic (or equivalent) torch like this one:
http://www.bernzomatic.com/item.html?id=18

There are other models you can check out, I think Home Depot or similar stores carry them.

Then check these guys out:

http://mdmetric.com/serto/
http://www.serto.com/chen/online-catalog/

Have a look at the Serto site and the catalogue and send the people at MDmetric an email with photos and see what you get in terms info on the needed parts.

Two fittings to solder, a replacement nut and some copper tubing is all you will need.
The bending can be tricky but if I could do it, so can you.
One trick is filling the tubing with water and freezing it, the ice inside keeps the copper from buckling.

Use those $65 to buy a torch, the replacement parts and learn to solder with silver.
Believe me, you won't regret it. :D

Cheers,

CIV