Keel Guards

Kevin Beam

Kevin Beam

Active member
I just finished replacing a section of a keelson that was worn through on a 14' broadbill I bought. I guess the boat had been dragged and beached one too many times by the previous owner, becuase she was down to bare wood. All the wood I went down to was in good shape, thank goodness. While investigating keel guard options, and realizing that they are $100+, I noticed an interesting setup on here where stips of 1/16" x 1" wide aluminum were used to keep the glass from getting worn out. I'm hesitant to drill holes in a boat I just patched up to fasten these things, and I'm considering just "glueing" the $4 aluminum strips on with West System G-Flex. I'm thinking even if it doesn't work, they'll just fall off.

Any thoughts as to whether they'll hold up with adhesive alone?

To better illustrate what I'm talking about, here's a pic from another member who screwed his down and used 5200 as well...

View attachment KeelGuards.jpg

View attachment KeelGuards.jpg
 
Last edited:
Kevin,I epoxyied mine and screwed mine down,I ruffed up the bottom edge to be glued so it would adhere better. I would definitely screw them down,also I would countersink too,hope this helps. Brian Rippelmeyer
 
Keiven,Are you asking if you shoulrd screw them down it looks like you have screwed them down.
 
Kevin ,

The guards look great , i used half round brass for that traditional look , not that they are really seen anyways , but when i replace them i will be going with Alum ans yours and will 5200 them as well as screw them down , good luck and nice job restoring that gem .



Dave M
 
Hey guys,
The pic I included is NOT my boat, I copied it from another post to help describe what I was talking about. I sounds like I should get some 1/2" stainless screws and and a counersink bit as brian stated. I'm embarassed to include a pic of the mess I've made of my boat today. Let's just say I not a glass man... Nonetheless, it'll work just fine.
 
Kevin

I've use 1/16" 1" wide aluminum on all my boats. Never had a problem after 10 years and countless beachings. Mine are put on with 3M 5200 and stainless screws countersunk 6" on center. The screws are only as deep as the keelsons and do not enter the plywood.

Eric
 
Last edited:
Kevin, As Eric stated bed aluminum in 3m 5200 screw down to the keelsons being careful not to penetrate the hull. Here are a few pics of what I did

Drilled and countersunk
P8160153.jpg

Installed with 5200
P8170148.jpg

P8170147.jpg

 
Kevin,

I used 1/8 by 1 inch aluminum strips countersunk and screwed down with 1/2" ss screws on my boats and they have held up fine while taking significant abuse. I think having them bent over the end of the keelson (like in Charlie's pics) helps keep them from catching on stuff.

-Bill
 
If your using S/S screws make sure you put them in Nalcotethat will eliminate the electrolisis factor. The 5200 will help you waterproof buts its not going to stop the galvanic action. A better choise for the keel guard would be a stip of half round S/S chafing strip that you can pic up at any marine supply store. Aluminum and underwater don't mix well.
 
I just finished replacing a section of a keelson that was worn through on a 14' broadbill I bought. I guess the boat had been dragged and beached one too many times by the previous owner, becuase she was down to bare wood. All the wood I went down to was in good shape, thank goodness. While investigating keel guard options, and realizing that they are $100+, I noticed an interesting setup on here where stips of 1/16" x 1" wide aluminum were used to keep the glass from getting worn out. I'm hesitant to drill holes in a boat I just patched up to fasten these things, and I'm considering just "glueing" the $4 aluminum strips on with West System G-Flex. I'm thinking even if it doesn't work, they'll just fall off.

Any thoughts as to whether they'll hold up with adhesive alone?

To better illustrate what I'm talking about, here's a pic from another member who screwed his down and used 5200 as well...
Click to expand...


I would have agreed with all that was said (except jack) a month ago, but in rehabbing my snowgoose I found that the 5200 on aluminum with SS screws is not a very good choice in a MARINE environment (actually I knew it before I did it, but I did it anyway thinking that it would last plenty long on a trailered boat).

In taking off my aluminum keel strips (I forget what series aluminum, but one commonly used in saltwater), I found that they were not bonded at all to the 5200. The mechanical attachment was stong and fine, but the 5200 did not hold as the aluminum oxidized underneath. A couple things, I've learned since then. John Catizone, our resident aluminum expert, suggests polishing of the bonding surface to remove the oxidation, as I did it I bonded the 5200 to the oxidation, not the aluminum (it isn't like the aluminum was overly oxidized, it was similar to charlie's he posted the other day). The aluminum keel strips are beat up in places and are still doing thier job fastened mechanically, but if you want them to stay on there forever in a marine environment consider doing it a different way.

I'll take some pictures, it is actually pretty neat the way the 5200 is bedded in a perfectly smooth layer under the removed strake. I imagined having to pry them off, but they just popped off. My plan was to replace with stainless anyway, so I'm doubly sure I'll do that.
 
Last edited:
If you don't want to pierce the outer fiberglas why not mechanically fasten aluminum to oak skids then glue the oak to the bottom of your boat? You could also do without the aluminum & go just with oak & treat it as "sacraficial".

Then watch it close. If the glue fails (what I would expect) not that hard, or expensive, to replace the oak skids with glue AND mechanical fasteners.
 
If you don't want to pierce the outer fiberglas why not mechanically fasten aluminum to oak skids then glue the oak to the bottom of your boat? You could also do without the aluminum & go just with oak & treat it as "sacraficial".

Then watch it close. If the glue fails (what I would expect) not that hard, or expensive, to replace the oak skids with glue AND mechanical fasteners.
Click to expand...


Gary,

You are right on the money. The strakes (skids) are wood strips (type up to builder) outside the hill that the metal is attached to. Screws shoudl not penetrate the hull in fastening the metal, I wouldn't think. This is the way Devlin designed them and they work well that way. My strakes are oak and were faced with aluminum. The wood and aluminum parts of the strakes are considered sacrificial, really.
 
Last edited:
Tod

I sanded the surface before applying the 5200 to roughen for a better bite and remove oxidation. If you had done that do you think your's would have popped off? I wonder if oxidation can occur after the 5200 has cured and weaken the bond over time.
 
Tod

I sanded the surface before applying the 5200 to roughen for a better bite and remove oxidation. If you had done that do you think your's would have popped off? I wonder if oxidation can occur after the 5200 has cured and weaken the bond over time.
Click to expand...


I just went outside and looked at it. I did sand them before I put them on - I can clearly see the sanding pattern from the random orbit in the aluminum, I would think I'd have done that, but didn't remember. I know I degreased them, since they came from the metal yarde very greasy.

A couple years back I talked to John because I was having trouble keeping the paint on them and he said he thought it was not galvanic action and just normal corrosion given what I expalined and he said that I would want to polish before I bedded them and polish and spray the part to be painted with zinc chromate primer. It is clear that the most severe pitting/aluminum oxide powder on the underside is associated with the screws. Most of the metal is fine (as I could see the sanding swirls) and the 5200 was bonded, though weakly. The oxidation clearly worked under the 5200.

Going stainless will have several upsides, both the corrosion resistance and they will be tougher. Origionally I was planning on stainless bar, but I got talked out of it by the metal yard because it is too hard to work with. I forget the price, I hope it doesn't hurt too bad.

T
 
Last edited:
I wonder how Grady-White used to attach its aluminum outboard brackets. In the 90's they had brackets which were bolted on and bedded with 5200. There was a recall and a number of them had to be removed. I was told that at times they would have 4-5 people standing on and hanging on a single motor bracket after the bolts had been removed and were unable to pry it off the transom. I think they had to pick them up with fork lift and drop them somehow to knock them off.

Was there any rot in your runners? If not, why do you need to glue/5200/epoxy the strips down anyway? Why isn't the mechanical fastening good enough?
 
Hello Kevin; I had David Clarke build me a Hummock a couple of years ago---he called it the extra wide on this site. It is absoutely fantastic---I have used it in Saginaw Bay which is full of rocks etc. especially now in the low water situation. I believe he used a stainless steel rub rail to cover all three of my keels. He is the guru of this sort of thing and contacting him should solve any of you concerns. Good luck. jerry
 
Hey guys, the dialog is great! I was really hoping to get some help on this. In light of possible electrolysis issues, and expensive stainless... What if I tried to use the plastic strips I've seen for boat trailer bunks, similar to Starboard? Sure, the bow piece may wear down, but thats the point... Here's a link to Starboard on Cabelas website:

http://www.cabelas.com/cabelas/en/templates/product/standard-item.jsp;jsessionid=WGQLILCN1TU3FLAQBBJSCN3MCAEFIIWE?_DARGS=/cabelas/en/common/catalog/item-link.jsp_A&_DAV=&id=0002190012509a&navCount=0&podId=0002190&parentId=&masterpathid=&navAction=push&catalogCode=IK&rid=&parentType=&indexId=&cmCat=netcon&cm_ven=netcon&cm_cat=Google&cm_pla=starboard%20marine&cm_ite=netcon&rid=0180101070502&hasJS=true&_requestid=78775

It's a little more pricey than the original $4 aluminum strips, but I could rip it on the tablesaw as thin as it would go without falling apart and have enough to pass around the entire site. They even have it in black.

Maybe someone has tried this and knows it won't work... That's what this place is all about!!! I really appreciate all the input so far.

Kev
 
I would view 5200 as a bedding material protecting the wood or fiber glass underneath. As far as holding aluminum or stainless questionalble. onelinemetal.com lists stainless .25"x1" at $6.46 per foot 304 stainless .25"x.75 at $4.84 per ft. You can buy a lot of aluminum for that price. Might be worth it though. I was pricing stainless for a chimmey cap 10' foot long by 4' wide the other day. I might have to go to the bank to pay for that but I look at it as never having to ever replace it. The angle iron to hold it in place was $135 without shipping.
 
Hey guys, the dialog is great! I was really hoping to get some help on this. In light of possible electrolysis issues, and expensive stainless... What if I tried to use the plastic strips I've seen for boat trailer bunks, similar to Starboard? Sure, the bow piece may wear down, but thats the point... Here's a link to Starboard on Cabelas website:

http://www.cabelas.com/...amp;_requestid=78775

It's a little more pricey than the original $4 aluminum strips, but I could rip it on the tablesaw as thin as it would go without falling apart and have enough to pass around the entire site. They even have it in black.

Maybe someone has tried this and knows it won't work... That's what this place is all about!!! I really appreciate all the input so far.

Kev
Click to expand...


You can use UHMW, it is workable with woodworking tools and is a dream to machine, but nothing sticks to it (almost) and it expands and contracts with temperature so it tends to want to break free if you do get something to stick to it. A good number of people use it for rubrails and stuff, but I think it needs to be a substantial to hold up using mechanical fasteners, especially to resist a strike or force perpendicular to the long axis. There are lots of PVC and similar rubrails out there at places like hamilton marine, but it is spendy (not as spendy as speciality stainless). I'll use flat bar 1/8" SS, I have to get a quote though.
 
Last edited:
Hi Kevin - I had a similar problem with the single keel on my 12' bbsb. I did not want to drill up into the keel and decided to try to glue a piece of oak. I was pleasantly surprised that this held up fine during the first season. Here's what I used:

At home cheapo they sell white oak molding and you can buy a pretty wide piece in half round in adequate lengths. I think I got a 3 inch wide half round about 10'. I used west system epoxy and, with the boat flipped, first fastened from the stern as far as the keel went forward without a bend. I thnk I lightly tacked with a screw or two to get started but the epoxy is the real bond. Once this set up I epoxied the forward end of the oak half round about a foot at a time with heavy weight added and strap so that it could set up. The oak took the bend and followed the hull ending about 2 feet short of the top of the bow without cracking. Then it was a simple matter of adding fillet down both sides to totally fill in the voids and sand.

sarge
 
You must log in or register to reply here.
Back
Top