I was surprised Friday, would appreciate some input.

[DK Custom Products]

This last Friday we decided to do some tests on different hose clamps.

Devin and I were both VERY Surprised at what we learned.

We have always tightened hose clamps down by visually noting how tight the clamp was getting on the hose.

This has worked for us on thousands of hose clamps, and I am sure that most of the billions of hose clamps currently in use around the world are tightened this way also.

What was amazing is how little torque it takes to get a hose clamp tightened down properly.

We purchased an inch pound torque wrench that was accurate down to 15 inch lbs, which is just a tad over 1 ft. lb.

Here is the surprising info we learned:

The photo below shows a hose clamp tightened down to the proper tightness.

It only takes 6-8 inch lbs to get it that tight.

18 inch lbs ( 1.5 ft. lbs ) is far too tight.

24 in lbs. ( 2 ft. lbs.) is so tight it is cutting into the hose.

Most hose clamps Failed (broke, and sometimes lost tightness, and sometimes did not) at 22-30 in lbs.

We were so surprised at how little it took we tested the calibration of our torque wrench.

These tests were done on 3/8" hose, using a quality, USA made worm drive hose clamp.

We also test a variety of other clamps, including pinch clamps.

How do you tighten a hose clamp?

Torque wrench, by feel, visually?

Any other info you can contribute would be useful.

We are going to publish a video of our test results, and include instructions on how to properly tighten a hose clamp. We would like to include any useful info you have that we may not already have in our footage.

Thanks,

Kevin

 

[rhino 2]

This last Friday we decided to do some tests on different hose clamps.

Devin and I were both VERY Surprised at what we learned.

We have always tightened hose clamps down by visually noting how tight the clamp was getting on the hose.

This has worked for us on thousands of hose clamps, and I am sure that most of the billions of hose clamps currently in use around the world are tightened this way also.

What was amazing is how little torque it takes to get a hose clamp tightened down properly.

We purchased an inch pound torque wrench that was accurate down to 15 inch lbs, which is just a tad over 1 ft. lb.

Here is the surprising info we learned:

The photo below shows a hose clamp tightened down to the proper tightness.

It only takes 6-8 inch lbs to get it that tight.

18 inch lbs ( 1.5 ft. lbs ) is far too tight.

24 in lbs. ( 2 ft. lbs.) is so tight it is cutting into the hose.

Most hose clamps Failed (broke, and sometimes lost tightness, and sometimes did not) at 22-30 in lbs.

We were so surprised at how little it took we tested the calibration of our torque wrench.

These tests were done on 3/8" hose, using a quality, USA made worm drive hose clamp.

We also test a variety of other clamps, including pinch clamps.

How do you tighten a hose clamp?

Torque wrench, by feel, visually?

Any other info you can contribute would be useful.

We are going to publish a video of our test results, and include instructions on how to properly tighten a hose clamp. We would like to include any useful info you have that we may not already have in our footage.

Thanks,

Kevin

I tighten by feel......And then when a little rubber starts to perdured out of the slits in the clamp, Its tight.....Been doing it that was since the late 1950's...

 

[Jack Klarich]

I tighten by feel......And then when a little rubber starts to perdured out of the slits in the clamp, Its tight.....Been doing it that was since the late 1950's...

I always thought that was a good way to tighten clamps, turns out that cuts the strands of the hose weakening it and causing failure sooner

 

[Jack Klarich]

I hate these clamps, if you have the right tool to install them it clamps good and does not cut the hose

Removal can be a chore tho

 

[rhino 2]

I always thought that was a good way to tighten clamps, turns out that cuts the strands of the hose weakening it and causing failure sooner

I can not recall when a hose i tighten that way failed premature ....Yes i had some fail from rubbing against something, And just plain old dry rot from old age..Or an exposed hose where the Sun or Heat bleach it dry and brittle...

 

[Jack Klarich]

I can not recall when a hose i tighten that way failed premature ....Yes i had some fail from rubbing against something, And just plain old dry rot from old age..Or an exposed hose where the Sun or Heat bleach it dry and brittle...

I had few failures also. But after seeing soooo many failures over the years ( many were from using the wrong type of hose for a petroleum carrying hose) and yes it can be a compound problem, a clamp too tight biting into and degrading the outer carcas of the hose and the fluid being carried thru the hose working against the inner of the hose.

Many points to ponder hmmmmmmmmm, my brain hurts:laugh:

 

[ultrafxr]

Kevin I did some googling around and found several recommendations. Most came is at about 30-40 in lbs for stainless steel clamps.

 

[ROAD DOG]

I hate these clamps, if you have the right tool to install them it clamps good and does not cut the hose

Removal can be a chore tho

I like these clamp's , They dont cut the hose like the screw type clamps, What's the plastic plumbing pipe's called is it pecks ? I bought a bag of those clamp's they fit 3/8 hose really good and bought the tool to clamp them , to get them off take a pair of cutting plier's and cut them .

 

[Jack Klarich]

I like these clamp's , They dont cut the hose like the screw type clamps, What's the plastic plumbing pipe's called is it pecks ? I bought a bag of those clamp's they fit 3/8 hose really good and bought the tool to clamp them , to get them off take a pair of cutting plier's and cut them .

I have a kit for making these type of clamps, I can make from 5/16th to CV axle boot size clamps

 

[ROAD DOG]

I have a kit for making these type of clamps, I can make from 5/16th to CV axle boot size clamps

That's cool were did you get it / never seen one

 

[Jack Klarich]

That's cool were did you get it / never seen one

Thru Napa, been probably 15 years ago back when I rebuilt rack and pinions and CV axles

 

[cScjhb]

Almost all of my clamping experience comes from the marine environment. But, I'll chime in here for what it's worth.

On almost all clamps, using moderately tight screw driver force is all that is necessary. When I can't get a screw driver on the clamp due to space limitations, I'll use a socket. I'm not a fan of tightening until the rubber squishes out of the clamp. As most of us know, hoses tend to "bond" to fitting over time making them difficult to remove even after the clamp is removed..... Jim

 

[DK Custom Products]

Thank you everyone for your input.

Video is in line to be edited.

We tested a variety of clamps, including some SS that had higher mechanical drag that required more torque to tighten. Still, even those were surprisingly small amount (3 ft. lbs.) of torque to tighten.

We really thought that pinch clamps would be a viable option...but on smaller hose, they just do not tighten enough for our satisfaction.

If I remember the numbers correctly, the pinch clamps pulled off the barb with only 35 lbs. of pull (and that was cold). Whereas a worm drive hose clamp, loosely tightened took 67 lbs. of pull, and a worm drive properly tightened could not be pulled off the barb.

Kevin

 

[DK Custom Products]

Not sure when Dwayne will have the video edited and up on youtube, but these photos show some of the really surprising information discovered in our testing.

This first photo shows the clamp tightened to a measly 26.9 inch lbs...barely over 2 ft. lbs.

And this is a close up of how incredibly over-tightened that hose clamp is on the hose at a mere 2 ft. lbs.

Now, when you do a google search, there will be results all over the place, including many saying to tighten to 20 - 40 in lbs.

There are clearly difference between different clamps, as will be shown in the video, but with the USA made worm drive clamps we use, the amount of force needed to tighten them properly is very small...AND it does not take much at all to overtighten.

Fortunately it is easy to see what is the proper tightness, and not go any further.

Kevin

 

[DK Custom Products]

Forgot to post a photo of a properly tightened hose clamp.

I've tightened them by sight thousands of times over the last 1/2 century and never had one fail.

The problem with people wanting to use machines is that different hose clamps have different levels of mechanical friction, so there is no reliable way to tighten a hose clamp without knowing what it should look like.

Kevin

 

[Sidecarbill]

You need the full circle type clamp. Think they may be called worm drive full circle clamps. The stainless band comes all the way around and covers those slots. They can't dig into the hose like that.

 

[Seaweed]

What I use on the boat. Probably overkill with the 316 SS for motorcycle but they have the rolled bands to protect the hose. Also everything on the clamp is stainless. Many "stainless" clamps use a ferrous tightener and that ends up rusting out. Again more for marine but things to look for.

[h=1]Scandvik ABA Hose Clamp[/h] Application: Corrosion-Resistant Hose Clamp, Select Clamping Range

Material: 316 Stainless Steel, Sold Individually

Smooth, Non-Perforated Band Surface with Rolled Edges Prevents Hose Damage

 

[ROAD DOG]

Honestly I have never had a problem with the thousand's of hose clap's I have installed . It's really tighten with a screw driver or a 1/4 inch socket . My dad use to use the that shallack glue shit on the inside of the hoses and double clamp everything the only way they came of was to cut them .