Nacra 5. 2 beam end caps

Great thread guys! This is why this site rocks. I too need a set of end caps. Looks like Nacraman 57 has the solution. Thanks Nacraman57!

Interesting Rob, I totally stripped the threads on one of my straps a few years ago and was told 10-12 lbs torque max.18-20 was a no no. Its hard to imagine putting enough force on those to deform the beam and not stripping the plate.!

If you need the name and number of my anti-seize, just ask, but use at your own risk. =)

edited by: yurdle, Sep 10, 2010 - 09:42 PM

Overtightening alone didn't cause the hull to crack there, although it certainly contributed.

"The Sea Was Angry That Day, My Friends, like an Old Man Trying to send Back Soup in a Deli."

Rob, Nacra may have missed a layer of laminate or something. Looks like they did on mine. Below my rear beam there was no laminate joining the beam bulkhead to the hull. The bolt started to rip through on my boat after some short steep waves hit the rear beam directly. I added some reinforcement and she's been holding up just fine now. You may want to check your boat too.

edited by: dennisMe, Sep 11, 2010 - 10:40 AM

Larry, if you look closely at the cross section of the beam you can see why they deform the channel so easily.
A) the beam is aluminum, & fairly thin stock-it bends with little force.
B) the geometry contributes to the problem. Look at Yurdles photo above. We all know that the easiest way to bend a strap is to place an object in the middle, then force both ends down. The beams channel has to be positioned in the worst place in order to properly orientate the tramps bolt rope. The resulting force, when the beam straps are tightened pushes nearly directly down on the channel. The only material to resist the crushing effect is the thin wall of the channel, & of the main beam itself. Look again at the beam end & you see that the force is being applied directly across both he channel & beam, essentially bending 2 thin strips of aluminum over a fulcrum. If the channel were rotated 90* it would withstand a much greater force, but you would have a hard time staying on a vertical tramp.
The engineers decided to use a low torque setting to avoid deforming the channel.
Yurdle, what is the green line through the beam? Nice clean job you did with the inserts as fairleads.

Green line is a barberhauler. It's a very clean way to install one on these nacras. Works great.

Well, if NACRA/Performance Catamaran/NACRA - US is longer offering these I wonder if they're going to stop making/offering the other NACRA specific parts?

Considering the factory is no longer in Santa Ana, CA, one has to look at this?

edited by: JohnES, Sep 12, 2010 - 09:02 AM

JohnES, you're saying that NACRA is no longer in Santa Ana??? Where'd they go? Not that it matters...I too share your concern that in the rush to build the next generation Infusion, or Capricorn, or Tiger, us "lowbrow" types are being forgotten. Anyway, this thread is supposed to concern itself with endcaps. And I say, if NACRA can't supply us with what we need, good old "redneck" engineering will! Hope the picture comes out right.

many countries require manufacturers to supply parts for up to 10years after model production stops....

i know this forum is one year old, but i was wondering where "nik1cod2" was getting those endcaps?
did anyone take him up on his offer and get some too? 😕

i need some!!!

I've got some. I'm trying to figure out what to do with my 5.5 and 5.2s. I know some of it will get parted out, and all the parts are a pain to find. I'll make some ads soon.

Rob

i have found that two dealers in australia are selling cast (alum i'm assuming) 4 inch dia. end caps for $34-$36 each plus s/h. yes, that's 'each'. but they should outlast all of us combined.
j

I've now got 4 extras, from the dead 5.2, in very good shape. I'll try to get them posted.

i have found that two dealers in australia are selling cast (alum i'm assuming) 4 inch dia. end caps for $34-$36 each plus s/h. yes, that's 'each'

Guys, just make your own for a few bucks total out of sch 40-3" pvc end caps and pipe. Just leave 3/4" for the tramp slotThere's more detail and explanation in my Beachcats People album

nacraman57, the beams on my 5.8 are 4 inch diameter, not 3 in. but i'm going searching for 4 inch pvc to see if i can make some like yours. i love makin' something from almost nothing! what type of saw did you use to slice the round end off.........a band saw? plywood (fine tooth) blade in a mitre saw?
j

nacraman57 wrote:

i have found that two dealers in australia are selling cast (alum i'm assuming) 4 inch dia. end caps for $34-$36 each plus s/h. yes, that's 'each'

Guys, just make your own for a few bucks total out of sch 40-3" pvc end caps and pipe. Just leave 3/4" for the tramp slotThere's more detail and explanation in my Beachcats People album

Those look great. Thanks for the tip. I now have another winter project. 😀

nacraman57, the beams on my 5.8 are 4 inch diameter, not 3 in. but i'm going searching for 4 inch pvc to see if i can make some like yours.

Arch...your beams are the same size as mine. All those early NACRA's had the same beams. The 3" cap is meant to fit OVER the 3" pipe so the rounded end is almost exactly the same diameter as the beam. The short length of 3" pipe goes INSIDE the beam. I think I cut it to a 3/4" length. Most caps I've seen have a line around the circumfrence of the cap end where it was pulled out of the mould. Use this as a guide to cut the cap end off. I used a fine tooth backsaw while rotating the cap in a vice then smoothing the saw marks by sanding it with 120 grit paper laid flat on a tabletop. Take the short 3" pipe, cut out a space for the tramp slot and force it into the beam. You can then measure the gap in the pipe to get a custom fit. For extra strength I used 1" screws to secure pipe to cap. The epoxy should be thick so it doesn't run before setting up

thanks nacraman57........of course they're 3 in. (what was i thinking??) pipe is inside diameter (duh).
can't wait to try this. i've used PC-11 epoxy on my boats when gluing down the hull covers after repairs. it's much stiffer than frosting and dries bullet-proof. that's what i'll use on the caps.

BTW, i emailed jack young at nacra and he said the cap mold is still around but the caps were injection molded and the manuf wanted a min run of several hundred before they would run them again. since it's an old design, nacra didn't wanna invest that much in a supply of new caps.
jon

I wonder if Jack would like to part with the mold . . .
Not much demand for the round end caps. Nacra no longer manufactures the round beams. All the current boats use the D shaped beam extrusions.

mummp: i don't think nacra had the mold. i think they outsourced the parts from someone who could do injection molding.

nacraman57: if the cap is plumbing pvc, then it should be possible to use the solvent that plumbers use to glue the pvc parts together instead of epoxy. it would set up in just minutes and be really strong after it fully cures. if you've done a plastic plumbing install then you know what i mean. it dissolves the pvc slightly, then hardens quickly. clear or purple color.

Supercat beams are a little bit larger, so no go on that.

I have some 'D' shaped ones for sale!

nacraman57: i've cut my cap and it fits over the beam perfectly but 3" pvc pipe is 3 1/2" O.D. (outside diameter) and this is too small to fit snugly inside the aluminum beam. there is way too much air gap between the pvc pipe and the aluminum beam. did you stretch your pipe out to a larger diameter after you cut it? 3 in pvc just isn't big enough to fit tightly inside the beam.

Arch, yeah seems to me I used a tapered piece of wood to force it against the inside of the beam. With the pipe half in, half out push the wood into the tramp slot gap. That's why you see the screws holding the unit together along with a thick epoxy. It was touchy drilling the holes (best to do it BEFORE the Busch Lite). Mark the depth on the bit so you don't drill through the cap. The PVC wasn't an exact fit but snug enough to hold in place while you put in the retainer screws. Had my doubts about the durability, but it's been over three years and they haven't broke yet. That's why I would recommend epoxy rather than solvent.

ATTENTION MANUFACTURER OF NACRA END CAPS!!!
this forum has had over 2100 views as of Nov 1 2011. apparently lots of cat owners are interested in these caps. won't you please make some more??? :remybussi:

a couple of years and how times have changed..........
the solution for this problem of plastic end caps may just be in 3D Printing. these printers are becoming common enough and cheap enough that someone (maybe YOU!) could scan in the different caps once and print them out for all of us who may need them.

http://www.youtube.com/watch?v=WmDz7Q9_h6c

just think of the possibilities.......any color, any cat, any beam end, all types of other non-loadbearing parts.........etc.

the start up cost would be too high for an individual to do 4 for himself, but we're talking obsolete, out of stock, long-gone parts that could be replicated.

be still my heart!
j

Edited by arch on Aug 04, 2013 - 07:45 PM.

I have end caps that will work just fine, and they are not too expensive. I will post a picture when I get back in town on Tuesday. Cost would probably be about $10 - $12 each. If there is really a market, I can knock a bunch out pretty quickly.

Craig I am interested in a set of your end caps. Any pictures you have would be of interest also.

If there is really a market, I can knock a bunch out pretty quickly.

Maybe start a new thread, NACRA BEAM CAPS, over the years quite a few people have expressed interest in beam caps. I'm sure there has been interest in 40-50 of them, though I realize that is a pretty small run.
PS, the photo of the bent 5.7 tillers might have gotten buried. PM or post if you would like any more specific measurements or photos. I left a proper camera there today.

Ed,

I'll probably put the end caps up at the same time I put the wing seats up.

The picture was a big help. I was also going to put my 5.8's rudders up on the 5.7 and compare to see if the bend ends in the same place as it does in your picture. The problem now is I have no desire to work on the boat as summer comes to an end. Every weekend possible is on the water.

Contact Murray's again, i think they are carrying an alternate beam end cap.
Here's the part # 56-2503
Tell them Chiindii Windsports sent you.