Why doe everything seem like 1/4 step forward and a full step back?

[rv_safetyman]

When I retired from Gates in '99 we were just finishing developing these "shrink-type clamps for the automotive market.  The issue they were trying to address were some cheap OEM (and aftermarket) clamps and the problems associated with them.  Automotive hose (as in cars) is really pretty cheesy hose.  It has tube and cover stock that is a compromise of cost and performance.  The reinforcing is a very wide open knit structure.  The problem is that the rubber (tube and cover) tends to flow over time and the effectiveness of the clamp goes away (unless you re-tighten it - folks don't do that kind of work much anymore).  The OEMs often used a spring type clamp, and I think they worked OK -- so not real sure what the development team envisioned as a market.

Gates found a good material that would shrink with heat (cousin to heat shrink tubing).  The thought is that the clamp would continue to shrink as the flow of the hose occurred.  Indeed, the thought was that the material  would flow less since the clamping force would be uniform and spread over a bigger area.

I am from the old school and I did not care much for the product.  It was not a big seller when I was there and I assumed it would die.  Guess I was wrong again

The hose we use (or should use) is quite different from hose used on cars.  Almost universally, it has fabric reinforcing (several layers) and is very robust.  The industry terminology for that hose is:  "wrapped construction".  It is typically built on a long pole and several layers of rubber and fabric are spiraled on.  A final layer of nylon wrap is placed on the hose before it is sent into the autoclave to be cured.  The nylon shrinks and causes the materials to bond under pressure and temperature.  The nylon is then removed, but the cover of the hose has that unique texture that makes it look like it has a fabric cover.

I am really amazed that the shrink type clamps work on that hose.  If BK was not a fan, I would tell people not to use it.  By far, my preference is the screw type clamps with a spring under the screw that maintains a constant tension.

Clifford, aren't you sorry you asked

Jim

[Busted Knuckle]

Bevans6 ~ yes they have to be cut off. But when we used them on a new engine install with all new hoses it was a very slick looking installation and never had a leak for the time we had had it!  ( I did have a plastic tote in a luggage bay with some spare old hoses & clamps of various sizes & utility knife just in case)

Clifford ~ Again looks like you've either done better research or had a better informant than I did. I do have the cut off tool somewhere in my tool box. (I think it was used once)
But I usually just take a utility knife and barely extend the blade out and kinda hold it more to the side than straight down and have cut off plenty of them and as far as I know never damaged the hose yet! (again as far as I know!)

Also I don't always use a heat gun, sometimes it is not practical due to space, lack of elec. power, or just that the smoke wrench or propane torch were closer. (yeah I know, I know they say not to do that!)
I have actually once used one without heating it at all on a service call on the side of the road when the propane torch had gotten bumped on while driving and was empty when I went to use it! (I tested it when loading up and it worked, 60 miles down the road and 2 hrs later when I needed it it was empty!) But these clamps work so well that once the engine starts producing heat they tighten them selves! (DO NOT try to use on a HOT engine &/or hoses or they will tighten up before you are ready!)

And yes I have used them on old hoses too. Can't reuse the clamp, but I have reused the hoses and used them on all types of hose not just the "blue" hose.

OK I ain't say'n I was supposed to do any of it the way I have, but I have done it that way and it has worked OK for me so far!
 BK  

[Busted Knuckle]

Ah I see Jim was typing while I was.

And Jim, I don't always ask the all the right questions. Or maybe I don't listen long enough to hear the right answers. But while I do remember them "only recommending using it on new hoses, I don't remember them say ONLY use it on new or even any certain type of hose!

But keep in mind the guy who turned me onto them was a NAPA Heavy Duty Parts Field Rep. who just happened to have some on his truck the day he stopped by and I was out on the lot of my uncles bus company next door to my garage tightening clamps because of a sudden temp drop in our area and it seemed every one of those old 318's developed at least one cold water leak over night.
Shoot he showed me how easy it was to put one one an the rest was history! My uncle had a cow when he got his next NAPA bill, but he didn't have cold water leaks no-mo! LOL!
  BK 

[belfert]

On this particular project I replaced six sections of silicone hose and one section of regular hose.  One of the silicone hose sections had split on my way to Florida and I was able to fix it while in Chattanooga with a wide band hose clamp.  I used two of the Gates Powergrip clamps and all the rest are the constant tension hose clamps.  I had to order the constant tension hose clamps from NAPA.

People must still be buying the Powergrip clamps as O'Reilly and NAPA have them in the local warehouse.  I can't imagine manufacturers using them as they would take longer to install than the spring type clamp they like to use now.  Even Detroit Diesel used the spring type clamps on the newer Series 60s.

[rv_safetyman]

It is pretty obvious that I put the shrink type clamp in the "stupid idea" category and was wrong.  I did feel that the concept was OK - that the clamp would keep nearly constant clamping force on the hose.  I just did not think there was a market for it. 

As I recall, the development folks had some sort of heating device that would "clamp" around the clamp and quickly heat it up.  The heating device was very small in wall thickness so that it could go around almost any hose in any application.  The tool was developed for the OEM

Now if you asked me if it would work on truck/bus type hose I would have told you no way.  When you think about how you have to tighten down a spring clamp, that gives you an idea of how much "shrink force" the Gates clamp has to exert.  Simply amazing.

Has anyone tried it on silicone hose?  I will look it up on the Gates site and see what I find, but don't have the time right now.

Jim

[belfert]

Has anyone tried it on silicone hose?  I will look it up on the Gates site and see what I find, but don't have the time right now.

I have four of the Powergrip clamps installed on three different sections of 2.5" ID silicone hose since 2007.  No leaks or drips even with -20 in the winter and 100+ in the summer.

I had a heck of a time finding much information on the Powergrip clamps on the Gates website.  All I really wanted was a listing of sizes and the matching part number.  One thing with the Powergrip is it only has a shrink range of 1/4" so there are many different sizes compared to worm drive clamps.

[Busted Knuckle]

Brian you are right as to what Gates says on the 1/4" shrink range.

But from personal experience just goofing off and shrinking one with nothing inside it they will shrink more than that.

But again from Gates point of view they only recommend 1/4" and I do understand that!
I also find the PowerGrip* that just does fit it while cold and then heat it for best results.
(and as I said I once put a hose on with a PowerGrip* on both ends that I had to really push the hose on over the bead with the PowerGrip* already in place. And started the engine and let it run while checking things and let the engine heat shrink them. Worked fine by the time I topped off the coolant it had shrunk good and tight! )

Jim, I am one of the few people I know that like them the way I do. Most mechanics ask me why ya wanna use a clamp that has to be cut off and replaced anytime it has to come off.
Well I have seen many worm type clamps stripped, broken, or overtightened to where they actually cut the hoses.

And (knocking on my head for wood) to this date I've never had a PowerGrip* fail me.
Just my way and I'm not always in the norm! LOL! But Setra's still rule! LOL!
  BK 

[belfert]

Back to my original vent.  I am still taking steps backward.  I've been to five truck parts places locally and none of them has the right size t bolt clamp.  I figured this would be a simple part to find.  There is one more place reasonably close and another one that isn't quite so close and then I end up driving 15 to 25 miles each way to any other place.

I've given up for now.  I might just put the broken part back on until I can order one or something.

[bevans6]

I buy t-bolt clamps at a hydraulic hose supply outlet, not from truck supply places.  FWIW and all, probably not helping you much at this point.  I know what you mean about how hard it is to get things finished, the last 20% of the work seems to expand exponentially.

Brian

[rv_safetyman]

Gates does not have much in the way of technical data on the PowerGrip clamp.  This is the best I could find:

http://www.gates.com/brochure.cfm?brochure=1539&location_id=3288

I am not sure if you have to be logged in to see that page.  If that is the case, I will try to post a PDF.

Jim

[belfert]

Gates does not have much in the way of technical data on the PowerGrip clamp.  This is the best I could find:

http://www.gates.com/brochure.cfm?brochure=1539&location_id=3288

I have seen this page, but no technical data as you say.  I did click on the E catalog this time and they do list the sizes there.  Even the E catalog is not a complete list as I have held larger sizes in my hand as recently as yesterday.

[Busted Knuckle]

Hmmm, I wonder where a busnut could find every size available? Hmmm....................

Oh I know, I know out on the hose and clamp shelf in my shop! LOL!
  BK 

(sorry couldn't resist!)