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Replace Bundy Pipes or Not?

PostPosted: Fri Aug 23, 2019 11:25 am
by Tmac897
I?m at the point in my restoration where I need to make some decisions about brake lines. I carefully removed the old lines and fittings before I refinished the frame, with an eye toward reusing, or at least reusing the old pipes as forms for new lines. Though still attached to the frame, they were disconnected from the MC, and have been ?dry? for more than 30 yrs.

I?ve already purchased new flexible ends to attach to the calipers. Telltale duct tape wraps told me all I needed to know about those.

But the pipes seem in good condition, and have the benefit of being ?original.? Pending some testing with compressed air for leaks, anything else of which I should be aware, or wary?

Re: Replace Bundy Pipes or Not?

PostPosted: Fri Aug 23, 2019 2:12 pm
by vxah
Not quite sure I understand about testing with compressed air for leaks? Where do you think they might leak? If there is the slightest doubt about their integrity then bin them and fit new, preferably steel rather than the horrid copper stuff!

Re: Replace Bundy Pipes or Not?

PostPosted: Fri Aug 23, 2019 2:26 pm
by Tmac897
Just trying to come up with a way to test the pipes for leaks before I reinstall them. Close up one end, connect other end to air hose, listen for any hissing. Or even paint the lines with soapy water and look for any bubbles. Not very scientific, but it works for natural gas plumbing connections, and hopefully can identify any obvious leaks and avoid having brake fluid all over my garage floor.

Re: Replace Bundy Pipes or Not?

PostPosted: Fri Aug 23, 2019 3:26 pm
by DavidLB
For what it costs I would replace with new non corroding kit of pipes from Automec David

Re: Replace Bundy Pipes or Not?

PostPosted: Fri Aug 23, 2019 5:29 pm
by MarkDa
Agreed on replace.
Brake pipes operate at much higher pressures than you will get out of an airline.
If you really want to test them cap off one end and connect the other to the master cylinder. Bleed through then apply considerable force on pedal.
This is one area that I wouldn't compromise.

Re: Replace Bundy Pipes or Not?

PostPosted: Sat Aug 24, 2019 11:13 am
by Tmac897
OK, thanks for your input.

Re: Replace Bundy Pipes or Not?

PostPosted: Sat Aug 24, 2019 1:41 pm
by Tmac897
Is there an Automec equivalent in the US?

Re: Replace Bundy Pipes or Not?

PostPosted: Sat Aug 24, 2019 2:46 pm
by Andy8421
I had understood that Kunifer (Cu Ni Fe), a copper nickel iron alloy was the pipe of choice for brake pipes. Steel corrodes, stainless is hard to flare without fancy tooling, and copper not permitted due to work hardening and cracking issues (at least I believe that is the case in the UK).

I tried to find out the composition of Automec pipes - a number of sites list them as 'copper' which is unlikely given the issues, Automec talk about cupro-nickel, so my guess is it is the same as Kunifer.

Re: Replace Bundy Pipes or Not?

PostPosted: Sat Aug 24, 2019 3:23 pm
by vxah
I use Oe type steel pipe with a paint over with clear wax oil type stuff, don?t go out much in the wet so corrosion isn?t really an issue.

Re: Replace Bundy Pipes or Not?

PostPosted: Sat Aug 24, 2019 5:37 pm
by mikealdren
Agree entirely with using Kunifer and brake pressures are about 10x typical air line pressures, 1400psi vs 120psi!

Re: Replace Bundy Pipes or Not?

PostPosted: Sat Aug 24, 2019 8:53 pm
by billwill
vxah wrote:Not quite sure I understand about testing with compressed air for leaks? Where do you think they might leak? If there is the slightest doubt about their integrity then bin them and fit new, preferably steel rather than the horrid copper stuff!



I'm in favour of Kunifer pipes (bronze ? ) it won't rust away like my old steel pipes did, yet it is stronger than copper brake pipes.

Re: Replace Bundy Pipes or Not?

PostPosted: Sat Aug 24, 2019 9:15 pm
by Tmac897
billwill wrote:
vxah wrote:Not quite sure I understand about testing with compressed air for leaks? Where do you think they might leak? If there is the slightest doubt about their integrity then bin them and fit new, preferably steel rather than the horrid copper stuff!



I'm in favour of Kunifer pipes (bronze ? ) it won't rust away like my old steel pipes did, yet it is stronger than copper brake pipes.


In the US most sellers list either stainless steel or copper / nickel.

Re: Replace Bundy Pipes or Not?

PostPosted: Sun Aug 25, 2019 3:52 am
by srineer
these folks

http://www.fedhillusa.com/

will sell you a spool of what you need, fittings that you need, and, for a nominal price, rent a professional grade flaring tool

Once they included the wrong flaring blocks; I did not notice the difference. When I returned the tool I included some of the flared lines I had made. They noticed the flares were incorrect for my application. They sent me a 25 ft spool, and the flaring tool, both at no charge.

good folks.

steve rineer
lititz, pa

Re: Replace Bundy Pipes or Not?

PostPosted: Sun Aug 25, 2019 4:20 am
by srineer
BTW, when I did mine I did not use a hacksaw to cut the tubing, I used a tubing cutter (plumbing aisle), then a file to make sure the tube was cut square, then used a tapered hand reamer to ream out the tubing...they are "good" hardware store items and not expensive, perhaps $15 or so for both. Harbor Freight has a tapered hand reamer for less than $3.00, but I got mine at a (ahem) more mainstream hardware store.

I dunno if it made a difference, but it really doesn't add that much time to the job, once you get into a rhythm.

good luck with your project...don't forget to put the fitting on the tubing before you flare the end. having said that, I think that everyone does that at least once.

steve rineer
lititz, pa

Re: Replace Bundy Pipes or Not?

PostPosted: Sun Aug 25, 2019 10:52 am
by Tmac897
srineer wrote:these folks

http://www.fedhillusa.com/

will sell you a spool of what you need, fittings that you need, and, for a nominal price, rent a professional grade flaring tool

steve rineer
lititz, pa


Hi Steve,

Thanks for the referral for fedhilusa, and the other tips. I?ve done enough DIY plumbing over the years to have my very own tubing cutter and reamer. In fact, you may find this amusing:

It was only about six weeks ago when I started this restoration. The Lotus was in a garage in No. Jersey, and I went up there to retrieve the frame, suspension parts, etc. As I was looking through things I found an old toolbox of mine. In that toolbox, among yet another set of sockets,etc, was a tubing cutter. My reaction was, ?Oh, that?s where that was.? So I really have two tubing cutters...

It?s a good thing I bought that Harbor Freight rolling tool box a while back.

Thanks again for your help.

Tony