Does anyone know what thread is on a 6mm flare nut/ male?
- Thread starter 1972Ren
- Start date
No idea but are you sure it is a 6mm and not some very close imperial size? 1/4 for instance?
I would try whatever threads I had on hand to see if anything goes in, or go to bunnings and try their selection of threads until something went in well. They also have UNF and UNC to choose from apart from imperial.
Measuring with a caliper might give a hint too. The root or crown diameter of the thread (or whatever is accessible) can be an identifier.
I would try whatever threads I had on hand to see if anything goes in, or go to bunnings and try their selection of threads until something went in well. They also have UNF and UNC to choose from apart from imperial.
Measuring with a caliper might give a hint too. The root or crown diameter of the thread (or whatever is accessible) can be an identifier.
Plenty of classic Renaults have imperial threads on the brake pipes - Lockheed! If you have a sample of what it has to go into, I'd take it to a good brake place and see if they can match it up.
I think he may be looking at a bleeder nipple.
he's just copying my question from a couple of weeks back. They aren't metric threads. Have a quick read here:
https://www.aussiefrogs.com/forum/index.php?threads/brake-cylinder-bleed-nipples.144437/
available everywhere and all over ebay.
The best is to take the sample into a place like Super Stop (in Box Hill, Melb - if you are a local) and get them to match it up.
I recall they are not metric, but were close and would screw in a bit before getting firmer, and by them you've probably stripped something you didn't want to.
So be very careful and 'measure twice and cut once'.
I recall they are not metric, but were close and would screw in a bit before getting firmer, and by them you've probably stripped something you didn't want to.
So be very careful and 'measure twice and cut once'.
More info, though now just as a matter of interest.
I have an old steel petrol tank (non french car).
It's outlet was just a piece of copper tube, but I wanted to install a bolt on fitting, so bought some 6mm copper tube from Reece Plumbing, and appropriate flare fittings. I called them 6mm, but yes I suppose they are correctly called 1/4" flare fittings.
As I had already brazed a larger nut onto the tank, I was considering tapping the nut so I could screw in one end of male-male 1/4" flare union. So was wondering what is the thread spec.
I thought it was 7/16th UNF. The thread pitch definitely matched a 7/16th UNF bold. But the flare nut wouldn't screw onto the bolt, and I don't have 7/16th UNF nut to check it on the flare male. Ok, thinks I, I will run a 7/16th UNF die over the thread, as it must simply be a different thread profile. That just buggered the thread.
In the end I brazed the male-make union in, and I still don't know what the thread is.
I have an old steel petrol tank (non french car).
It's outlet was just a piece of copper tube, but I wanted to install a bolt on fitting, so bought some 6mm copper tube from Reece Plumbing, and appropriate flare fittings. I called them 6mm, but yes I suppose they are correctly called 1/4" flare fittings.
As I had already brazed a larger nut onto the tank, I was considering tapping the nut so I could screw in one end of male-male 1/4" flare union. So was wondering what is the thread spec.
I thought it was 7/16th UNF. The thread pitch definitely matched a 7/16th UNF bold. But the flare nut wouldn't screw onto the bolt, and I don't have 7/16th UNF nut to check it on the flare male. Ok, thinks I, I will run a 7/16th UNF die over the thread, as it must simply be a different thread profile. That just buggered the thread.
In the end I brazed the male-make union in, and I still don't know what the thread is.
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The plumbing fittings that you bought from Reece will be BSP threads. Imperial brake fittings are UNF and are not compatible with BSP threads.
For easy DIY at home you would be better off with compression fittings. I think you would be better off removing that fitting you brazed onto the outlet of the tank and clean in up the best you can and use compression fittings.
These compression fittings are available in brass and stainless steel.
Maybe if you explained exactly what you are trying to achieve the advice would be less general, there is plenty of experience here to help guide you.
Just so everyone can have at least one good laugh for the day, this is the full story of what transpired.
*Brazed a nut on side of tank. Drilled to 6mm. Brazed a copper tube into that. Would have all been fine; just needed to attach flexible fuel line with a hose clamp but decided it wasn't well positioned, so...
*Brazed another bit of copper pipe to the front of the tank, and cut/brazed the first one shut.
*Used an epoxy tank sealant (hint: warm the resin up ALOT if using one, as the epoxy is otherwise hard to coat over all internal surfaces). Despite blowing air in through the outlet at some length, it ended up rather restricted with expoxy. Like, unusably.
*Thinks: oh screw it I will braze a male-male union into the original nut and make a flared fuel line hose. Went to Reece for said parts. Took the tank outside as using the gas welder now made it belch burnt epoxy fumes. Being outside I didn't realise how much I was heating the brass fitting, and melted both the ones I bought.
*Next day, back to Reece Plumbing for more fittings. Went to try again, and the acetylene ran out.
*Went to BOC for replacement bottle. Next day, when I went to have another attempt, I moved the gas bottle trolley and, not having put the restraint chain on, both bottled fell over, broke both oxygen gauges and the bottle pressure acetylene gauge.
*Went to buy a new gauge, swearing at myslelf in the car, and bought an acetylene gauge which I didnt really need, rather than an oxygen one. Got home, realised mistake, went back for the other gauge.
*Brazed the flare fitting in. Great! Cut off the other, redundant outlet, tried to braze it shut, but - suddenly! - there is a hole in the tank.
*Cut a 0.75mm steel plate and brazed that over the hole.
*Finally, after looking at this item on 6 consecutive days, it has the desired outlets and no leaks. THANK GOD.
*Re-sealed inside to replace the burnt epoxy.
On the plus side, my skills with brazing sheet metal, and copper / bronze do-dads have improved immensely.
*Brazed a nut on side of tank. Drilled to 6mm. Brazed a copper tube into that. Would have all been fine; just needed to attach flexible fuel line with a hose clamp but decided it wasn't well positioned, so...
*Brazed another bit of copper pipe to the front of the tank, and cut/brazed the first one shut.
*Used an epoxy tank sealant (hint: warm the resin up ALOT if using one, as the epoxy is otherwise hard to coat over all internal surfaces). Despite blowing air in through the outlet at some length, it ended up rather restricted with expoxy. Like, unusably.
*Thinks: oh screw it I will braze a male-male union into the original nut and make a flared fuel line hose. Went to Reece for said parts. Took the tank outside as using the gas welder now made it belch burnt epoxy fumes. Being outside I didn't realise how much I was heating the brass fitting, and melted both the ones I bought.
*Next day, back to Reece Plumbing for more fittings. Went to try again, and the acetylene ran out.
*Went to BOC for replacement bottle. Next day, when I went to have another attempt, I moved the gas bottle trolley and, not having put the restraint chain on, both bottled fell over, broke both oxygen gauges and the bottle pressure acetylene gauge.
*Went to buy a new gauge, swearing at myslelf in the car, and bought an acetylene gauge which I didnt really need, rather than an oxygen one. Got home, realised mistake, went back for the other gauge.
*Brazed the flare fitting in. Great! Cut off the other, redundant outlet, tried to braze it shut, but - suddenly! - there is a hole in the tank.
*Cut a 0.75mm steel plate and brazed that over the hole.
*Finally, after looking at this item on 6 consecutive days, it has the desired outlets and no leaks. THANK GOD.
*Re-sealed inside to replace the burnt epoxy.
On the plus side, my skills with brazing sheet metal, and copper / bronze do-dads have improved immensely.
These are HVAC flare fittings, so they are not BSP.
It's done now, and the flare fittings are perfect for fuel lines, but I will look at the compression fittings for future reference. Plus I had the flare tools from when I replaced brake lines.
*I have just had a look at that, and yes compression fittings certainly would be easier than bothering with the flares. Thanks.
Noted and thanks, but I still don't know what the thread is on the flare fittings!
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