R-Hop Source Material

Little Bird · Nov 5, 2013

Howdy folks, I thought I'd jump on here and spread the R-Hop love far and wide.

You all know how and why they work, no edumucation needed there. You also all know that R-Hop kits from various retailers *cough* scalpers *cough* are $$$ for a few pieces of silicone or EDPM rubber.

On a recent backpacking trip, I looked down at a small MSR water filter of mine and had a revelation. The water filter has a input and output hoses made of a soft, flexible tubing. It was a cold morning, a little above freezing, and the tubes were still flexible. When I got home I cut an inch off, made an R-hop patch, and popped it into my field gun. Sure enough, it worked. A few minutes on the phone with MSR customer support gave me exactly the information I needed. Off to McMaster-Carr.

THE STRAIGHT DOPE

The "IR" (all-season) R-Hop tubing is made from 5/16" OD, 3/16" ID High Temperature Semisoft Silicone tubing ordered from McMaster-Carr. The item # is 51135K17. It's available in four colors for your...coloring pleasure: Opaque Black, Opaque Red, Semi-Clear Blue, and Semi-Clear White. I use Semi-Clear Blue, personally. My next order will be Opaque Red, just to be different. This stuff is teh sex in all seasons. I've used it with great success (for most glorious Kazakhstan!) in -12 °C (~10 °F) weather here in Utah. All of my AEGs use this tubing.

Link

The older R-Hop material is made from EDPM tubing from Autozone or O'Riley's Autoparts. For the sake of convenience, it's also available from McMaster-Carr too. Again, it's got a 5/16" OD, 3/16" ID, and has a part # of 9776T4. It's 60 cents a foot too. This stuff isn't as flexible in the winter and IMHO it's pointless to use now that the silicone tubing is available. On the other hand, I could see it's use in something like an LMG that's going to have thousands of rounds being pumped through it. Of course I dunno if I've ever heard of anyone wearing out an R-Hop anyway, silicone or otherwise.

Link

Go forth, multiply, and spread the love!

PS: Silicone R-Hop tubing is (at this point in time) 90 cents a foot from McMaster-Carr. An HS5 "Z-Hop" kit is 25 bucks from ASGI or 23 from HS5. The "Z-Hop" kit comes with ~1.5" of tubing. Rounding up for waste, that's 23 bucks for two inches. It would cost you $276-$300 to buy a foot of the stuff from ASGI or HS5. ALL ABOARD THE NOPE TRAIN TO FUCKTHATVILLE. CHOO CHOO! :bird:

pkidd · Nov 5, 2013

Can you post a picture of your setup?

Little Bird · Nov 5, 2013

Could you please be a little bit more specific? Setup means a lot of different things to me.

Dorekido · Nov 5, 2013

I think his mean is a picture for prove your matterial above can fit in inner barrel

Little Bird · Nov 5, 2013

The tubing itself.

I'm a good ways away from home right now, so I don't have any pics of the finished product. I'll be back at home later this week and I can pull some images off of an external drive.

pkidd · Nov 5, 2013

Yeah I would love to see pictures of it installed.

4ce · Nov 5, 2013

Do you try soft one? Because i think more soft is the rubber more good are

but i'm not 100% sure

Desert Sniper · Nov 5, 2013

When I order some I'll order both the soft and the semisoft so that I can compare the performance of each.

@ Little Bird. Thank you very much for posting this up, I've been wanting to buy an R-hop but have holding back because of the price. Now I can buy an entire foot of it and make tons of them! :tup:

I wander what this will do to HSArmory?

Little Bird · Nov 5, 2013

The soft works too, but I find the semi-soft easier to work with (sanding, cutting, etc.) My first order was four feet of the soft, but my second order was 4 feet of the semisoft. The stuff that was on my MSR water filter turned out to be semisoft (I took a shot in the dark when ordering). The semisoft worked so well that I just kept using it.

I do find that with the soft tubing, you can use stock rubber nubs on most AEGs with success. But, if you want to use the semi-soft, you need to use a harder nub. I use H-nubs on all of my guns, so semi-soft is the way to go for me. If you don't have H-nubs, use cut up pieces of a bic pen ink tube. It works surprisingly well.

What will it do to HSArmory? Meh, I don't really care. He did good in bringing the concept to light, but I don't like the fact that he's charging highway robbery for a couple of pieces of tubing that he doesn't even manufacture himself. Look at the math I did at the bottom of my first post. My blood pressure goes up just thinking about it.

buzzjam · Nov 5, 2013

Well HS5 made it clear that the R-hop idea is open source in the first place, so I'm sure he's well aware of people trying to make their own r-hops already. I personally use a tubing with a 1/4" ID, so that I can keep the high quality finish of the stock inner tubing.

TheTJ · Nov 5, 2013

If he wanted it to be completely open source, he would have identified the material he used and where he got it from. He wants to make his money.

Killer · Nov 5, 2013

Weve been over this already. There already has been a thread regarding the R-hop material. Heck, I even PM'ed people what it was, who were interested.

In regards to the R-hop, you do get a nice cut slice when you order at HS5, where as this is for the more advanced and skilled tinkerer.

It was known quite a while that the original R-hop was EPDM rubber. Jonesy (Excuse me if i misspell your name) discovered this quite a while ago, and even sold it on his webshop i believe.

To each their own.

Plazmaburn · Nov 5, 2013

Hmm good thing I need to order stuff from mcmaster, I think I shall tack some on to my order.

cetane · Nov 5, 2013

I have a 10' section of the blue and clearish ones at home, but ordered the 8mm od, 6mm id one. I will give the ir hop a go in the coming future.

Little Bird · Nov 5, 2013

Nice! I just ordered 2' of the 6mm ID 8mm OD one to check it out. If it's any easier to work with compared to the smaller tubing, I'll let you guys know. I might be upgrading the barrel in my DMR in the near future, so it's a perfect excuse to try something new.

TheHunter · Nov 6, 2013

How do you guys cut this stuff!!!!! I have tried tinkering with some tubing but can never get a cut good enough to satisfy me. Does anyone know how HS5 cuts it so perfect?

Dorekido · Nov 6, 2013

me too, not sure I can handle cutting work for perfect fit

Little Bird · Nov 6, 2013

I just use a wicked sharp razor blade. It takes a few tries to get the technique down. I simply cut the requisite length of tubing to fit the window, set the tube on end, and then cut down the tube vertically. It works every time.

Little Bird · Nov 6, 2013

I've been tinkering with an idea in Solidworks to see if I could make a jig for cutting the tubing. A problem with cutting it by hand is that unless you're perfectly vertical with the razor blade, the patch could end up being wonky. One end has longer legs than the other. Something like this might be able to be 3D printed and used to cut the legs in .015" (the thickness of an average razorblade) increments.

Slip 1/2" of tube in, pick the best fit, and make the cut. Presto, perfectly cut R-Hop patches.

Of course you'd need two blocks, as the above block uses the first cut to bisect the tubing with all the secondary cuts mirrored off of it by .015". A second block with the first cut offset by .015" from the center plane would allow for cuts to be made for pretty much any hopup window known to man.

TheTJ · Nov 19, 2013

Revisiting this cutter idea... Since the outer diameter of our tubing is now 9mm...

We could fit the tubing into a 9mm barrel and dremel the window sizes of hop windows all the way down to a point, and then fill the bottom side so the tubing bottoms out and has no way to slip out of the barrel. Then, take a generic box cutter blade with a small heat resistant handle attached to it, heat it with a lighter for about 10 seconds, and slice directly through the tubing like butter.

I've yet to try it but it seems like it could work, in theory.

Plazmaburn · Nov 6, 2013

I had that same idea Little Bird.

I think HS5 uses a laser or water jet to cut his stuff. I could be thinking of someone and something else entirely.

FalloutState · Nov 7, 2013

I just got mine in today, along with the x-acto knife I ordered from McMaster as well. The X-acto knife cuts the tube like it's nothing, so if you can line it up well, then you should be golden.

EDIT: And yes, I tried it out, and with pushing straight down and cutting back, I got a very nice cut.

Dorekido · Nov 7, 2013

just buy silicone tube ( OD 8mm, ID 5mm ), after cut cut cut, I got 2 patchs nicest, put one in my AKM, seem pretty nice ( but I turn a lot of hop-up because I cut outside a little bit more wahahaha ). I got some pieces excess, and I just wonder: is it can make act like a flat nub? it decompress faster, lenght and thick enough to do. tomorrow I will try. sorry if this off topic

Masterjuggler98 · Nov 7, 2013

Actually the nub is an interesting idea. If you cut a piece of the tubing into a U shape and glue the legs to the hop arm, and leave some space between the legs so the rubber can squish. I'll have to try that.

I'll order some of the tube soon to play with. Right now I doing other things.

Dorekido · Nov 7, 2013

buy smaller ID/OD tube, easy like a piece

Little Bird · Nov 7, 2013

Using the tubing as a concave nub is a good idea, but I don't know if it'll work.

The reason being is this, the semi-soft tubing takes quite a bit if pressure to deform it compared to a regular hopup bucking. The soft squishy nub of most hopup arms just can't press down hard enough. I have to use cut up bic pen tubes when I don't have H-Nubs avalible for customers.

If we could find a HARD tubing that's small enough to cut into a useable concave nub, I think we'd be in the money.

In fact, now that I think about it, the really small "trickler" sprinkler tubing might work. This stuff.

Dorekido · Nov 8, 2013

I don't need concave nub, flat nub is purpose I want to lead >

, i put the small piece on table, press by finger and see it will provide flat contact. Not sure if it same like in hop-up unit ( test on AK hop-up unit )

but I will order H-nubs to compare :hehe:

Masterjuggler98 · Nov 7, 2013

I've experimented with a few different kinds of nubs (working with a bar10 here by the way) and I, and others, have found the the softer the nub, the better when using a hop patch like the r-hop. The reason being that the soft nub puts uniform pressure along the whole hop patch, unlike a hard nub which can put uniform pressure on the patch, but is less likely to. Right now I'm using foam from a nerf dart because it's really soft, but it keeps permanently compressing when the hop is left on for too long.

I'm probably repeating what you already know, but I just want to put it out there why I don't want a hard nub.

How soft is the soft or very soft tubing? I have a feeling if I used a soft rubber for the nub instead of my foam, I can leave the hop turned on without the nub permanently compressing like my nerf dart foam nub does.

Sorry I'm hijacking the thread a little bit. Would you rather I make a different thread about this, or is it fine because it's about the tubing you found?

Plazmaburn · Nov 7, 2013

I wonder how the tip of a nerf n-strike clip system dart would work as a nub?

These in case you dont know.

If its been done, how did it turn out?

Masterjuggler98 · Nov 7, 2013

I just ripped out the rubber tip from one of those darts and cut some of the thin rubber off. If I roll it up I could glue it on, and it looks like it'll work pretty well. I'll put it on later.

Just for clarification, I've been using the foam from those darts you linked to as my nub. I've had some confusion about that in the past.

I can stick my hand under my couch and pull out five of those darts LOL. We have so many around the house, it's a little sad.

Desert Sniper · Nov 8, 2013

I actually ordered a foot of the soft tubing along with the semi-soft so that I could see which one worked better for my setup. But when I got it, it was a lot softer then I expected so I am going to try and make a nub out of it and will post up the results if you guys are interested. I don't think that I will have any issues with compressing at all seeing as how it's a real nice soft silicone and it seems pretty flexible.

I should be getting my new hop up and barrel any day now, so as soon as it get those I'll do all the testing and that fun stuff and post up the results.

Tupp9 · Nov 8, 2013

any results on how these are working???
also, someone wanna post up a link? im having trouble finding these

FalloutState · Nov 8, 2013

The link is in the first post in the thread..

TheHunter · Nov 9, 2013

I have found a harder nub works better than nerf foam. I use an eraser and get way better results than nerf foam and the foam doesn't very nearly long. The eraser is also way more consistant.

Dorekido · Nov 9, 2013

I don't have much luck with eraser, pain like @** to cut it straight :doh:

R-Hop Source Material

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