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toadster
07-28-2020, 12:01 AM
Looking for a Recommendation for 3/8th fragola braided stainless fuel line

TMartinLVNV
07-28-2020, 12:46 AM
Battery cable cutters. Seriously. Works great.

toadster
07-28-2020, 01:01 AM
from the fragola site



Cutting the Fragola Performance Systems Series 3000/6000 stainless braided hose is easy. Wrap the hose with Gray” or masking tape at the length desired.
Hose may be cut with a hack saw, if you have a 32-teeth-per-inch blade, otherwise a Beverly Shear, radiac, or chop saw will work fine.
You want to keep the braids from fraying. After the cut, carefully remove the tape and trim from the frayed ends if necessary.

I tried tin snips with horrid results (as expected) - I may try my hacksaw first before spending $30-60 on a wire cutter...
sadly my braided cutter I have is only good for up to 5/32 cable...

i.e.427
07-28-2020, 01:15 AM
Tape with duct tape or electrical tape and cut with an angle grinder using a thin cut-off wheel. Been doing this way for years with excellent results.

egchewy79
07-28-2020, 06:09 AM
+1 on battery cable cutter

jrcuz
07-28-2020, 06:13 AM
I used cutters made for electrical cable with great results.
JR

edwardb
07-28-2020, 06:23 AM
Tape with duct tape or electrical tape and cut with an angle grinder using a thin cut-off wheel. Been doing this way for years with excellent results.

X2 same here. Mostly. Tape wrap then a thin cut-off wheel on a Dremel. Done a bunch of them that way.

NAZ
07-28-2020, 07:49 AM
Yes, I've cut the SS braided hose with a hack saw in a pinch when the right tool was not available but it's not a very good way to cut hose and a cut off wheel is even worse. But if you go that way, be sure to clean out the interior of the hose of debris. If you're the kind that grabs an adjustable wrench for 90% of your work, you'll probably keep sawing through SS braided hose. But at least be aware there are tools made for this job.

If you're going to work with SS braided hose, use the correct tools. A cable cutter makes a clean cut but most use short handles that will get old after a half-dozen cuts. Here's the tool made for cutting SS braided hose: https://www.summitracing.com/parts/sum-900040 Do yourself a favor and purchase the right tools for the job. Tools are expensive but they are an investment in the hobby or profession you have chosen.

Logan
07-28-2020, 08:21 AM
Ironically I just finished my second batch of PTFE-lined braided stainless hoses last night. These ones were power steering hoses. I used a battery cable cutter, which is a 9” pliers with heavy duty concave jaws arranged just like a typical pair of scissors. They put two tiny kinks in the PTFE liner since the hose gets flattened during the cut, but it opens back up perfectly round with no trouble at all, and no affect on the joint integrity. Fittings attach beautifully. Best part? Takes 1/4 the time to do compared with my previous method, and requires ZERO cleanup.

My fuel lines are the same PTFE-lined hoses, and I did the tape and grinder with thin cutoff disc method. Never again. Cleaning the hose out with Q-tips and rubbing alcohol is slow and annoying. Not to mention I’m still going to have to flush the lines before connecting them to my engine.

Quicker and cleaner cuts with the battery cable pliers. Takes 1 second to make the cut, and you’re adding the fitting immediately after. What more could you ask for?

Papa
07-28-2020, 08:24 AM
Another vote for using a cutoff wheel. Be sure to clean the lines out after cutting to remove any debris.

Jeff Kleiner
07-28-2020, 09:12 AM
Tape wrap then a thin cut-off wheel on a Dremel. Done a bunch of them that way.

Same here.

Jeff

toadster
07-28-2020, 11:50 AM
I tried the tape/hacksaw method for one end last night, not perfect but got the ferrule seated and tightened the connection

Fragola suggests to wrench down to about 1mm gap - does this one look ok?

132596 132597 132598

I'll probably try the tape/dremel solution today and compare notes :)
trying not to buy a $60 cutter for 6 (well now 5) cuts needed

Papa
07-28-2020, 11:59 AM
I used push-lock connectors from Fragola, so much different look, but what you are showing looks good. If you can't pull it off the end of the hose, should be good to go.

egchewy79
07-28-2020, 12:03 PM
I tried the tape/hacksaw method for one end last night, not perfect but got the ferrule seated and tightened the connection

Fragola suggests to wrench down to about 1mm gap - does this one look ok?

132596 132597 132598

I'll probably try the tape/dremel solution today and compare notes :)
trying not to buy a $60 cutter for 6 (well now 5) cuts needed

off topic question, but do you know if Fragola PTFE connectors are different than other AN connections? I have a custom length piece of fragola SS braided PTFE fuel line that I got from Forte (ends already attached) that I needed to shorten. I bought a -6AN PTFE fitting online and the ferrule/olive is way too large for the hose. Not sure if Fragola has their own sized connectors that are different than others.

NAZ
07-28-2020, 12:21 PM
I tried the tape/hacksaw method for one end last night, not perfect but got the ferrule seated and tightened the connection

Fragola suggests to wrench down to about 1mm gap - does this one look ok?

132596 132597 132598



I'll probably try the tape/dremel solution today and compare notes :)
trying not to buy a $60 cutter for 6 (well now 5) cuts needed

Looks good in the photos -- give it a very hard tug to ensure it's going to hold. If this is a high pressure line it's best to pressure test them but if you don't want to spend money on tools, you really won't want to shell out what it takes to pressure test hoses.

NAZ
07-28-2020, 12:27 PM
off topic question, but do you know if Fragola PTFE connectors are different than other AN connections? I have a custom length piece of fragola SS braided PTFE fuel line that I got from Forte (ends already attached) that I needed to shorten. I bought a -6AN PTFE fitting online and the ferrule/olive is way too large for the hose. Not sure if Fragola has their own sized connectors that are different than others.

All mil-spec AN hose & fittings are compatible, but I suspect not all AN hose and fittings are mil-spec. As for PTFE hose and fittings, they are not made to a common standard so you MUST use manufacture specific hose and fittings. You may get lucky and find some compatibility but more likely you will find there is just enough dimensional difference between manufacturers to cause a problem. Also, when using PTFE get the type that is conductive (usually black) as fluids flowing through the PTFE hose will cause static discharge that can damage the hose.

jrcuz
07-28-2020, 02:37 PM
The cutter that NAZ linked in his post look like what I used and are less expensive. I got mine at Home Depot in the electrical dept.
JR

rich grsc
07-28-2020, 02:40 PM
off topic question, but do you know if Fragola PTFE connectors are different than other AN connections? I have a custom length piece of fragola SS braided PTFE fuel line that I got from Forte (ends already attached) that I needed to shorten. I bought a -6AN PTFE fitting online and the ferrule/olive is way too large for the hose. Not sure if Fragola has their own sized connectors that are different than others.
Take the fitting apart, cut hose, reconnect?

egchewy79
07-28-2020, 04:16 PM
Take the fitting apart, cut hose, reconnect?

The fitting I got was direct from fragola and doesn't appear to be a reusable fitting. Looks like it's a permanent crimp. Plus I'd like to switch from a straight to a 45* for better geometry

rich grsc
07-28-2020, 04:40 PM
The fitting I got was direct from fragola and doesn't appear to be a reusable fitting. Looks like it's a permanent crimp. Plus I'd like to switch from a straight to a 45* for better geometry
OK, many times they are two piece fittings and can be reused.

egchewy79
07-28-2020, 06:04 PM
OK, many times they are two piece fittings and can be reused.

I was hoping it'd be that simple, but nothing ever is on this build

rich grsc
07-28-2020, 06:27 PM
Thats true for many of them. Had my own issues over the years too.

toadster
07-28-2020, 07:45 PM
off topic question, but do you know if Fragola PTFE connectors are different than other AN connections? I have a custom length piece of fragola SS braided PTFE fuel line that I got from Forte (ends already attached) that I needed to shorten. I bought a -6AN PTFE fitting online and the ferrule/olive is way too large for the hose. Not sure if Fragola has their own sized connectors that are different than others.

one thing I've read in the fragola content is that the ferrule (olive) isn't re-usable and should be replaced - the screw ends can be re-used many times over..

finally got my first 2ft section installed, once the return line is in - i'll mount both with some clamps, probably on the down-post on the back of the tank
first cut was a hacksaw, 2nd cut was a dremel
132634

I'm going to borrow a set of cutters tonight to see if that's any better/easier than the first two :)

CraigS
07-29-2020, 06:38 AM
All mil-spec AN hose & fittings are compatible, but I suspect not all AN hose and fittings are mil-spec. As for PTFE hose and fittings, they are not made to a common standard so you MUST use manufacture specific hose and fittings. You may get lucky and find some compatibility but more likely you will find there is just enough dimensional difference between manufacturers to cause a problem. Also, when using PTFE get the type that is conductive (usually black) as fluids flowing through the PTFE hose will cause static discharge that can damage the hose.
I agree. Back in the 70-80s most any braided hose was from the aircraft industry so most all was interchangeable. But now there are so many different types, different liners, etc that I always buy fittings that are the same brand as the hose. For me the potential downside is just not worth the risk.

Hoooper
07-29-2020, 10:39 AM
Fragola PTFE fittings use an olive for the seal in their fittings. The olive is a one-time use, the rest of the fitting is reusable, and you can get the olives for relatively cheap. I havent had any trouble using Fragola and Summit PTFE hose ends with Vibrant PTFE line.

phileas_fogg
07-29-2020, 12:13 PM
For pressure testing hoses, I used this: https://smile.amazon.com/gp/product/B009S5ICJY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1. I use a bicycle pump to pressurize the hose to 80-100 psi, and submerge the fitting under test in a bucket of water. Then I wiggle that fitting every which way I can. You'll quickly dislodge any air bubbles that resulted from dunking the hose, and be able to see if the fitting is leaking at all.


John

toadster
07-30-2020, 09:25 AM
For pressure testing hoses, I used this: https://smile.amazon.com/gp/product/B009S5ICJY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1. I use a bicycle pump to pressurize the hose to 80-100 psi, and submerge the fitting under test in a bucket of water. Then I wiggle that fitting every which way I can. You'll quickly dislodge any air bubbles that resulted from dunking the hose, and be able to see if the fitting is leaking at all.

John

that's not a bad price!!

BTW - I did borrow a set of cutters - 100% best way IMHO, such a satisfying 'chonk' when it cuts and it's perfect!

Logan
07-30-2020, 10:28 AM
Told ya. :)

Glad you see how much faster, easier, and cleaner it is now. Knock the rest of your hoses out now!

NAZ
07-30-2020, 11:16 AM
that's not a bad price!!

BTW - I did borrow a set of cutters - 100% best way IMHO, such a satisfying 'chonk' when it cuts and it's perfect!

If you plan to do more work with AN hose, consider buying either an AN hose cutter or a stranded electrical cutter, both are interchangeable but the electrical cable cutters tend to have shorter handles as copper strands are easier to cut than SS. Once you've used the correct tool it's easier to justify the expenditure.

As for pressure testing hose, I don't bother with anything that only sees 300 PSI or so but when you start getting into high pressure hydraulic you may want to invest in a pressure tester that will test to at least the pressure the hoses will see in normal operation (1000 plus PSI typically). For those less expensive testers that use a Shrader valve don't be afraid to go higher than 100 PSI, most air service Schrader valves have a 150 - 300 PSI operating range. And they are available in much higher pressure ratings for hydraulic service. The valve itself is rated higher than those rubber valve stems you normally see them in.