It didn't take long to need a repair to my new to me boat. The aft keelbolt anchor is coming out. It looks like there was a half ass repair job performed. Can anyone give me some guidance for the repair? I also had been reading about keel box insert kits is this an added piece that should be installed or the fix itself? Thanks for the help in advance!
What hull number
#106
Contact a rondar rep to get the keel box cassette. I think they have the threads in them and eliminate the old threaded inserts.
The keel guide cassette is the way to go Tom.
Easy to install and provides an extra layer of safety in the event of a grounding.
Your existing inserts should be removed so that the guide can be installed.
I don't have one in stock, but I do believe Paul Zim has one.
If you have questions, feel free to call me 415-543-7333.....drew
The keel guide might not work and even if it does, you might be interested in a more "secure" alternative.
We've had several guys down here run aground - not hard enough to hurt anything - yet the keel guide an back nut insert came loose, ending their event.
I just did some work on a boat where the keel was too wide for the insert - the first revision from rondar wouldnt' even go over the keel. The second one installed damaged the keel so we pulled it out and put in a teflon insert that kept the to of the keel in place and drilled / tapped a piece of G10 under the aft lip after repairing the top.
If you want some pictures, let me know.
Quote from: Jeff Jones on August 14, 2011, 11:16:56 PM
The keel guide might not work and even if it does, you might be interested in a more "secure" alternative.
We've had several guys down here run aground - not hard enough to hurt anything - yet the keel guide an back nut insert came loose, ending their event.
I just did some work on a boat where the keel was too wide for the insert - the first revision from rondar wouldnt' even go over the keel. The second one installed damaged the keel so we pulled it out and put in a teflon insert that kept the to of the keel in place and drilled / tapped a piece of G10 under the aft lip after repairing the top.
If you want some pictures, let me know.
I've got #24 and #56, both of which have potential issues. They're holding their own, but what's this cassette thing? Photos of any solutions would be great.
#56 has the high density plastic keel guides, which seem to be pretty rugged, and a keel shaped trunk which was leaking some but I found and filled all the major leaks. See below for possible end-all solution for possible hairline crack leaks.
#24 has a rectangular keel trunk and the keel foil itself is somewhat irregular. There are no guides aside from the composite reinforcing around the opening in the hull. The top of the box has rectangular plate the size of the standard keel plate, made out of a ~1/4" metal plate with the foil cross section cut out. It's screwed in around the edge of the top of the keel box and has two threaded studs coming out at the same locations where the keel bolts normally screw in. The keel plate sits directly on top of this and bolts on. The whole thing seems like some sort of retrofit. I'm debating putting in the plastic blocks. If there's a better retrofit, I'm interested.
As an aside, I've considered painting the inside of the keel trunk with rubberized RIB bottom paint to create a flexible seal. Any thoughts on that?
I am also having Keel bolt issues. My forward one seems to be holding fine, but the aft was a embedded wing nut that just popped out. Any suggestions on how to fix it?
Olaf, that sounds like a retro-fit. I'm only aware of two keel trunk styles on the bennett's. Have any pictures?
Darren, i have the same issue. I'm going to try and tackle it this week.
Quote from: Jeff Jones on August 15, 2011, 09:18:36 AM
Olaf, that sounds like a retro-fit. I'm only aware of two keel trunk styles on the bennett's. Have any pictures?
Yeah, here's a few.
(The very mangled keel plate has been replaced)
That's crazy.
The metal guide looks like what i've done. Used HDPE at first, now tefon sheet. It's a great, simple system.
Hey Jeff,
Do you have an NC mill or waterjet? Nifty looking. That fits inside the trunk box? How's it kept in place?
I might be interested in ordering one from you.
I think the guy that did the ones I have was also having issues with keeping the bolts threaded in, so he made this thing with the studs coming up and said nuts on top.
What's at the hull end? (nothing on#24)
Also, what do you think of my RIB rubberized bottom paint idea as a trunk sealant? Any better products come to mind?
We have a pretty handy cnc table with 18" of z.. I'm not smart enough for 3d work, but am pretty handy with acad and 2d stuff like this. If you can draw it, i can cut it. I've got a ton of HDPE plate around but not much teflon left (the teflon is pretty expensive - yet cheaper than a keel job)
One thing i really like about this guide is that it only contacts about 1" of the front and back of the keel. The sides are wide enough that there's about an 1/8" gap on either side.
To install it; I glued some frp tabs down inside the keel box with plexus. Their drilled and tapped to accept this piece.
and that's actually not a horrible way to secure the keel.. if you bugger up the bolts like Darren has you can take the thing out and replace them. But it does raise your keel about 3/4" right?
For my keel bolts i think i'm going to take some G10 plate, cut 1" round pieces and stack them with glue. Then - glue them up under the deck where the keel bolts go and drill / tap into it. That will give me a female thread to bolt into that is very secure. And - i'll stack enough so that i wont drill / tap all the way through - keeping water out of the hull at that point.
Here are pics of keel box cassette I got from Rondar last August. There were no inserts - I was told to position it on top of the existing inserts and drill hole so I could continue to use them. Purpose was not to help with keel bolt issues but just to glue it in and have it act as a sacrificial shock absorber of sorts (Paraphrasing Andy at Rondar here). In case that didn't work out they did also give me a few new inserts to epoxy in if necc. Note that the fore and aft 'tabs' have carbon cloth reinforcing on them. I did not install it yet because it was not a good fit to the keel profile - way too tight to slide up and down without gauging the keel sides.
Have been meaning to sand it down some and glue it in over the winter - of course that will leave me with exposed glass rubbing against the keel which is not great either.
BTW this was for #108 so about as close to 106 as you can get.
Maybe they have modified the insert since last year ?
the other pic
You've got a typical case of "FKS" (fat keel syndrome)
Same thing happened when i tried to put these over the keel of 115 and 103. I wouldnt go the sand and fit route. Paul came out and installed a V2 over 115 and 103's keels. 115 was still snug and the keel got buggered up. Thus, the new teflon job.
If it's not a tight fit on the front and back Chris maybe you could just cut most of the center out, leaving just the adjoining strips to hold the ends dimensionally stable. Not sure the sides do anything in the center. And since your orgional keel bolts are there you dont need the mass to hold those down, you just want to keep the keel from banging around in the box when it's not down.
I think the ticket would be to widen the keel box to 3", put in some front / back guides that will keep the keel from banging around when its not down - then go with vertical guides on the side of the keel / keel box that will lock it in place when it's down. That should also take a lot of pressure off the keel bolts. Of course, there goes your break-away box.
Quote from: Chris Shaughnessy on August 17, 2011, 02:46:59 PM
Here are pics of keel box cassette I got from Rondar last August. There were no inserts - I was told to position it on top of the existing inserts and drill hole so I could continue to use them. Purpose was not to help with keel bolt issues but just to glue it in and have it act as a sacrificial shock absorber of sorts (Paraphrasing Andy at Rondar here). In case that didn't work out they did also give me a few new inserts to epoxy in if necc. Note that the fore and aft 'tabs' have carbon cloth reinforcing on them. I did not install it yet because it was not a good fit to the keel profile - way too tight to slide up and down without gauging the keel sides.
Have been meaning to sand it down some and glue it in over the winter - of course that will leave me with exposed glass rubbing against the keel which is not great either.
BTW this was for #108 so about as close to 106 as you can get.
Maybe they have modified the insert since last year ?
Anyone know where to get the black acryilic keel guides for a Mk II. Hull #100. Boat has the two black top and bottom acrylic plates. Or is there a template out there to make your own?
Thanks for any info.
Craig
Craig,
Rondar has the template for those. Email Paul Young or Dave Hall for new ones. They can ship them to you directly.
[email protected][email protected]
Spoke with another fellow who's had a big issue with his rondar keel system. To help fix the problem he had some small shims made that fit in front and back of the keel where it enters the hull. There was a large gap in these areas which allowed the keel to rock forward and back - putting a bunch of stress on the insert / bolts.
What's the hull number? Did it have keel guides installed? I always get this info back to Paul Young.
I'll send you an email. Very new hull number - very good sailor.
Quote from: Drew Harper on August 22, 2011, 12:02:33 PM
What's the hull number? Did it have keel guides installed? I always get this info back to Paul Young.
This is timely. We have hull #80. It has the plastic block recessed into the bottom that keeps you from wrecking the hull in the event of a grounding (which we tested spectacularly at Charleston a few years ago). There is a matching plate fastened to the top of the rectangular keel trunk with 10 screws. Fastened to the bottom of this plate are two studs from http://www.bighead.co.uk (that's the first picture). Big wing-nuts go on these studs to clamp the keel to this top plate.
We've managed to break one of the studs: it looks like metal fatigue caused the "big head" of the stud to simply crack & fail. I need a replacement, but I have never liked the studs & wing-nuts for two reasons:
1) We sometimes have trouble getting the keel to slip nicely over the studs and need to horse things around a bit before we get it to drop on. Besides being annoying, it seems hard on the studs.
2) We keep getting lines snagged on the wing nuts. Annoying and sometimes kinda slow.
So here's a question for the rules/technical committee:
Can I replace the studs that come up through the black plate with a Big Head Nut (the second picture) and use a bolt & washer to fasten the keel to the boat instead of the wing-nut? Will that be "class legal"? The boat owner is very worried about the "strictness" of the "one design". Can I get an authoritative answer?
In this thread I see there is a "keel guide cassette" that might or might not fit my keel, requiring fiberglass work, yada, yada, yada, recommended for hull #106 which I presume came out of the same molds as #80. Looking at the picture I see no particular advantage over the present system. What have I missed? Anything?
The cassette will not work in hull 80 You can legally switch the bigheads to the other style you've shown. There was a limited series of boats delivered with the studs. The rest are the other style.
Thank you very much -- I guess I have to order the Big Head Nuts from England. I hope they don't want me to buy 100 or them or something.
I would replace it with a T-nut from your local hardware store instead of ordering any fasteners from the UK.
Hmmmm.
It seems these come in stainless. I'll give that a go, thanks.
Quote from: Zach Freeborn on August 22, 2011, 07:36:10 PM
I would replace it with a T-nut from your local hardware store instead of ordering any fasteners from the UK.
We have had some major issues on jackpot, an incident in Charleston on some rock pile with a big sign on it, and in miami on one of the reefs trying to sail in and out of the harbor. We had something similar the t-nut from the factory. Hull #119. The problem isn't the t-nut or similar products its the strength of the area you embed it into. having guides put in will help if you hit stuff and bulking up that back area where the keel bolt goes in. We cut the shelf out that was there, it was 3/8" thick, and epoxied a piece of stainless steel with a drilled and tapped hole. It was an easier fix for me since i'm better at working with steel than fiberglass/gelcoat.
Yes, there isn't much material to hold the what, #12 screws? Once they tear out you can try putting in a bigger screw but this is a tenuous fix. On #80 there ain't no 3/8" of material -- half that at best. I'm not sure Bennett/Young intended for the screws to tear out of the hull they way they did. I can't do the normal "fill the hole with epoxy & drill a new one" sort of fix I'm used to doing because there isn't enough material there to hold the new epoxy. I am disappointed in this aspect of the build, there should be more material there. Period.
But they did tear out, and I did put bigger screws in, and I am sure this will have to be repaired properly some day. The boat's owner does not want inspection ports installed, so I suppose I'll be looking for another (waterproof) solution I can do completely from the top. The only thing I have thought of so far will be (as my father says) a wooly-booger of a job (but it would be strong & waterproof and would not require modifying other parts).
To follow up on the keel bots parts, BigHead has a US distributor:
http://www.kvt-koenig.us
and the part I want to replace the keel hold-down studs on #80 is this one. It'll fasten exactly where the stud went and poke up into the black plastic keel guide/plate but won't protrude from the top. I measured the holes in the aluminum keel plate and it'll take a 10mm bolt so that's what I'm planning to use. I'll let everyone know about pricing.
A fix for the screwed in plastic plate that you can install from above is a rectangular plate of 3/16 g10 cut to fit in the deck rebate and also cut with the rectangular box sized cutout in its center to be bonded into the recess. This would provide a thicker flange that could be drilled and tapped to accept the fasteners from the plastic plate. The plastic would remain removable if there is a need to access the keel bolt bigheads. The bigheads are meant to break at the welds if you hit bottom hard. I can talk anyone through this that may be interested.
Ben
Thanks Ben. I'd thought of something like this, but it'll make the black plastic plate stand proud of the bottom by 3/16+", right? Plus you'll have only 3/16 of material to hold a thread. I could attach BigHead nuts to the 3/16 plate and cut recesses in the black plastic to make them clear to get something stronger I suppose. That black plastic is 3/4" thick -- I could plane that down by 3/16 to make it flush... Oh drat! Now I'm modifying parts...
Still -- this might be the best solution.
The BigHead aft where the screws tore out is not the one that broke! I wouldn't count on welds breaking to protect any plastical parts.
A #10 fastener tapped into g10 will hold better than a wood screw into a few layers of fiberglass. Correct though. it would raise the plate by the thickness of the g10. Run it through a tablesaw on edge to thin it down more easily than planing.
Alternatively you could riddle the plastic with additional holes in between the ones that are stripped or go for a few strips of g10 and the blind insertion method.
just do this and be done with it already.
I think cutting the thing out was the hardest part.
So there i was, just finished a red bull when i ran out of epoxy. No more work on the fordeck cap. Hmm.... i've aways wondered what's under there. And then the saw came out.
It's your fault steinberg
Oh and if you have a Bennett that's leaking i'd bet money that some of it is coming from the joint in the keel trunk. The top part of the trunk is glued over the bottom part (socket fit) with what looks like west / microspheres. After 15 years of banging around that stuff can micro-crack. You'd be surprised how much water pressure there is in your keep trunk when your sailing along at 14 knot's.
KVT Koenig's minimum order quantity is 100 pieces and he says he doesn't have a "sub distributor". Maybe I'll have to go with t-nuts after all, but I don't think they're 316 stainless.
You'll be glad you did. (Eventually) Ben's keel boxes DO NOT LEAK.
Quote from: Jeff Jones on September 06, 2011, 10:32:07 PM
just do this and be done with it already.
I think cutting the thing out was the hardest part.
So there i was, just finished a red bull when i ran out of epoxy. No more work on the fordeck cap. Hmm.... i've aways wondered what's under there. And then the saw came out.
It's your fault steinberg
Jeff...wow...more pictures please! That's #31 right?
I'll take a bunch of detailed pictures through the process.
Ya, that's 31. She's getting an new foredeck cap so i figured while i'm at it.
Since I haven't found an economical way to obtain BigHeads, what about a 316 SS or bronze or titanium (saves weight!) thread repair coil like HeliCoils installed directly into the plastic keel guide plate? Will they grip the plastic tightly enough to withstand repeated tighten/loosen cycles? Will red locktite stick to that plastic?
Does anyone know the technical name of that material so I can talk to an engineer at the HeliCoil company?
I have an idea for how it might work:
1) Drill the "oversize" hole from the bottom of the plate just deep enough for a coil
2) Use a bottoming tap to cut the oversize thread to accept the coil
3) Install the coil from the bottom of the plate
4) Make sure the hole from the top of the plate is just large enough for the bolt
Voila! A metal thread installed directly into the keel guide plate.
The coil can't move upwards in the plate because there's plastic in the way. If it wants to move downwards at all, it can't go far because it'll hit the deck of the boat. But it might not want to move.
t
http://www.noblefix.com/PDF/Helicoil/HeliCoil%20Catalogue.pdf
I talked to a sales support engineer at HeliCoil (Robin) who told me that there should be no problem whatever installing a HeliCoil in the plastic keel guide plate (I take it to be some kind of nylon). If you look on pages 18 - 19 of the catalog (link in earlier post) you'll see that the recommended DRILL size in plastic is different from the size recommended for steel. The size of the TAP is the same for any material. She says as long as you're confident you can cut a clean, sharp thread in the plastic, the HeliCoil will not move under the conditions we need for the keel bolts without any need for an adhesive (finger tight wing nut torque) . They have three highly corrosion-resistant materials to choose from.
So, I think I have found a solution that avoids the need to buy 100 BigHeads. I plan to install an M-8 HeliCoil with a 1.5 diameter thread length. I can see putting HeliCoils in G-10 and carbon masts too: these things would be good for any part you might want to disassemble from time to time on the Viper.
Heli coils work well but typically threads get burnt out in applications where the bolt is frequently threaded and unthreaded like the keel bolts. I'd rock the t nut or make my own big head.
We used to heli coil ski bindings all the time. That coupled with some bad ass epoxy, good to go.
I put a Helicoil in the foward hole on #50. Ben is right, it won't like the repeated screwing & unscrewing. Lasted > 1 season for me. YMMV.
Sent from my Tab or phone => brevity & Swypos
make your own big head. Get some 5/16 id stainless tube and run a 3/8 tap through it. Bring it to your local welder and have them weld it to a fender washer. good to go.
As Paul Y. to grab a handful from the shop before he heads over for Sarnia, figure 2 bigheads = 1 beer ?
I thought about making my own out of bronze because it'd be easier to cut a thread in and I could braze instead of having to weld. There is one guy I know of who I'd trust to weld a 316 part and maintain its corrosion resistance. He could do it over the winter. But this is a last resort. I'd probably go with whatever grade of SS t-nut
If there is an economical way for me to get four Big Head female sockets in an appropriate size, I'll take it. I haven't tried offering Paul beer for boat bits, only money. My bet is 1 Big Head = 2 pints at least. I'm sure those parts cost quite a bit, and then there's the "remember to ship" charge and the "transportation charge".
If you're going to the trouble of making fasteners, I would reccommend using
a 5/16" or 3/8" "Stub Acme thread" which would hold up to repeated use much better than a standard V thread.
Dimensions for 5/16" x 14 pitch, stub acme thread.
External thread - Major Dia .3125" , Minor dia .2597" , Pitch dia .2871"
Internal thread .3225 .2696" .2911"
On the mk.2, the keel bolts into a plastic plate that is in turn screwed to the deck as opposed to the threaded sleeve in the deck on the mk. 3 deck. To install the t-nut, all you have to do is enlrge the holes in the plate to fit the nut, there is no fiberglass work involved.
Quote from: Lee Shuckerow on September 06, 2011, 03:33:28 PM
Quote from: Zach Freeborn on August 22, 2011, 07:36:10 PM
I would replace it with a T-nut from your local hardware store instead of ordering any fasteners from the UK.
We have had some major issues on jackpot, an incident in Charleston on some rock pile with a big sign on it, and in miami on one of the reefs trying to sail in and out of the harbor. We had something similar the t-nut from the factory. Hull #119. The problem isn't the t-nut or similar products its the strength of the area you embed it into. having guides put in will help if you hit stuff and bulking up that back area where the keel bolt goes in. We cut the shelf out that was there, it was 3/8" thick, and epoxied a piece of stainless steel with a drilled and tapped hole. It was an easier fix for me since i'm better at working with steel than fiberglass/gelcoat.
What's the verdict on using T-nuts to replace the big head bolts? Has anyone dome this? My keel bolts are shot and my plate no longer screws down to the hull anymore with the forward 2 screws. I'm trying to think of solid ways to fix this, but I keep coming back to the blind G10 method. There has to be something easier...