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View Full Version : How to get 6 brazed parts apart at the same time.



outsider347
01-06-2016, 03:46 PM
I am replacing the tunnel assy in a 1979 Porsche 911. The tunnel is the conduit that houses everything that needs to go from the front, to the back of the car.

Inside the tunnel steel tubing, of various diameter is brazed to the end cap of the tunnel. I'd like to keep the steel tubes in tact so I can re braze them when I get the tunnel welded in

There are 6 tubes that are brazed in. The end cap has to come off of all 6 at the same time ...........
Picture getting a 6 prong IC soldered to a pc board removed

I used to service electronic gear, and I used to un-solder 1 leg, and blast the it with component chill spray. Messy , sometimes worked

Wondering if anyone might have a good trick to accomplish this without making a mess of the thin wall steel tube

Tks for your suggestions
ed

jackdawg
01-06-2016, 04:29 PM
Sounds like sourcing some more steel tube might be simpler.

roadkillbobb
01-06-2016, 04:49 PM
got a picture?

tapwelder
01-06-2016, 06:59 PM
Photo would be helpful? Why so important to get them out at same time. If location/position is an issue then mark and take photos before removal of individual tubes.

rlitman
01-06-2016, 07:08 PM
I'd cut a section out of the end cap, and weld that back into the replacement.

outsider347
01-06-2016, 08:41 PM
Pics of tunnel
1314021131403113140411314051

the 6 tubes are what I am referring to. The flanges, I'm not worried about

I'd rather not cut then weld the steel around the tube, as I am attempting the "un tampered/repaired" look when the resto is done.

2 of the tubes are vacuum so can't have leaks

Hope I answered the questions

tks Gents

ed

Sedanman
01-06-2016, 09:07 PM
This is seriously redneck and dangerous so don't try this at home. That being said, l would have an air blow gun ready and heat one joint to the point of liquifying the braze and then blow the filler out of the joint. Do this to all of the joints. Have a backstop on the other side to catch the splatter. Wear LOTS of protection!

roadkillbobb
01-06-2016, 09:13 PM
why cant you unbraze the pipes from the body tube? and then take them out 1 at a time..

outsider347
01-06-2016, 09:15 PM
I was thinking the same thing...but thought I'd see what you guys thought

outsider347
01-06-2016, 09:19 PM
why cant you unbraze the pipes from the body tube? and then take them out 1 at a time..

I wanted to leave the tubes affixed at the opposite end, so they end up registered to the original position

roadkillbobb
01-06-2016, 09:25 PM
make a wooden template for the other end so when you put the pipes back in they are perfect..

outsider347
01-06-2016, 09:31 PM
Better clarification... I hope!

I'd like to get the end cap removed from the new tunnel, so when I install it , the tubes which are welded in many places to the inside of tunnel, so I can simply run the tubes thru the (original) end cap that is sill affixed in the car. then weld the replacement tunnel in

roadkillbobb
01-06-2016, 09:33 PM
make a wooden template, just like the end cap you want to take out, but for the other end..it will hold the pipe positions when you reinstall them..

outsider347
01-06-2016, 09:46 PM
make a wooden template, just like the end cap you want to take out, but for the other end..it will hold the pipe positions when you reinstall them..

The other end (front) has only 2 tubes, doesn't have the end cap. so no problem with the front
all of the tubes are welded to the inside of the tunnel . I'd rather not cut the tubes loose from the tunnel

roadkillbobb
01-06-2016, 09:51 PM
then a couple of friends with torches...lol

tapwelder
01-06-2016, 10:03 PM
I assume the entire assembly is the tunnel. You want to keep the part with 10 or 12 tubes protruding through it. If that is the case, then cut it out as close to the manifold thingy as possible, then heat and unwrap like an old tuna can.

Sharon Needles
01-06-2016, 10:56 PM
I'm wondering if you could use a braided ground strap type material as sort of a giant solder wick. Heat up the braze and wick it away from the joint with the strap.

outsider347
01-06-2016, 11:09 PM
I'm wondering if you could use a braided ground strap type material as sort of a giant solder wick. Heat up the braze and wick it away from the joint with the strap.

Since the braze is a majority brass (I'm guessing) what material should the braided strap be?

roadkillbobb
01-06-2016, 11:12 PM
just heat the braze up and wipe off with a wire brush..........

outsider347
01-06-2016, 11:14 PM
just heat the braze up and wipe off with a wire brush..........

sounds like a good place to start

Smurph
01-06-2016, 11:42 PM
Since the braze is a majority brass (I'm guessing) what material should the braided strap be?
Had to do something similar. It was copper to brass with silver solder and I used a brandy new weld brush. It coated the brush in silver and was the envy of all the other welders. I assume steel is your best bet.

denrep
01-07-2016, 01:50 AM
Torch in one hand, air blow-gun in the other.
Warm filler to melt and blast away with air; repeat.

Smurph
01-07-2016, 02:11 AM
Torch in one hand, air blow-gun in the other.
Warm filler to melt and blast away with air; repeat.

Wear coveralls. Scratch. Suit of armor.

denrep
01-07-2016, 09:27 AM
Wear coveralls. Scratch. Suit of armor.

Naaah, not with decent aim.
But it wouldn't hurt for coworkers to suit up, and to put the dog out. :laugh:

outsider347
01-07-2016, 05:46 PM
Got it done
1315371

The blow it out with air method didn't work at all. Only cooled it down quickly

Had to sacrifice the end cap.....Cut into sections around each tube.
Wire brushed the heavy's, then pealed the metal around the tube carefully

What worked well on the 3rd one, was to trim around tube, put a little flux on, heat to molten again, then I was able to slide the steel off the tube

Thanks to all for suggestions
ed

Mr. Smith
01-07-2016, 05:56 PM
As a Porsche nut, I thank you for not butchering those tubes to get them out.

rlitman
01-07-2016, 06:05 PM
Nice work!

outsider347
01-07-2016, 08:12 PM
As a Porsche nut, I thank you for not butchering those tubes to get them out.

For sure!
............I have to put all this back together
I just got the replacement F. floor section, pedal section, & front suspension pan from Restoration Designs. Nice fitment metal from those folks