Cox Roller Trailer Restoration

[jfret]

Has anyone seen a similar setup converted to bunks.?.....When I bought this trailer I was hoping I could convert it to a bunk trailer primarily for cost reasons.  Now I'm not so sure it can be done with the existing wobble roller configuration in place.  I found replacement wobble rollers and keel rollers, (blemished) for $4 each. I need 32 of them so that's a decent savings. It also needs brakes, tires, springs and electrical so I will have some coin in it....finding the best price on these parts a must.

[RickK]

Roller trailers have their place and they are used in places that don't have great ramps and/or the tide swing is a lot more than say here, in FL, where we have a 2 ft swing max.  Here in FL we primarily use bunk trailers and have ramps that are not too brutal so we can launch easily.
If you have nice launching facilities in NC then a bunk trailer may work out fine for you.
Have you looked at places like Sturdybuilt trailers http://www.sturdybuiltonline.com/Boat-Trailer-Bunk-Brackets_c_101.html
They have all the parts you need to convert.

[GoneFission]

It is fairly easy to convert your roller trailer to bunks and (IMHO) bunks reduce the point-load on the hull compared to rollers.  The Cox trailer is a bit of a put-together design instead of a fully welded trailer - that makes it easier.  Ideally the bunks go under the boat stringers - so you need to measure the distance between the stringers on the boat and set up the bunks on the trailer.  The bunks should be 4x6 or 4x8 supported at two points near each end to allow some "flex" to match the contour of the hull.  So you will need 2 sets of bunk brackets for each bunk.  The bunks need to be long enough to go all the way from the transom to where the curve of the hull causes the bunks to separate from the hull.  Cypress is the preferred wood for bunks to prevent rot. 

Hope this helps - good luck!   

[Capt. Bob]

Here is some good reading for your project.

http://classicaquasport.com/smf/index.php?topic=8686.0

And a few additional thoughts once converted.

http://classicaquasport.com/smf/index.php?topic=11607.0

Lastly, since you got it in pieces, you might want to go all the way and become a convert.

http://classicaquasport.com/smf/index.php?topic=12822.0

Good luck and post pics as you go.

[jfret]

Once again....thanks for the input and information and links. I'm going to make the conversion to bunks....but I'm not looking forward to getting those rusty bolts out that hold the front and rear frames to the main frame....better get out the extra long cheater bar and hope they break! Will post pictures after the carnage and swearing is over.

[Capt. Bob]

Turn this:


Into this:


With this:


Nothing unloosens rusted fasteners like a little Oxy-Acetylene.

Good luck.

[gman 82 aquasport]

Got to love an easier way out..torch or cut off wheel is the best way to go when not re-using parts.

[jfret]

Got to love an easier way out..torch or cut off wheel is the best way to go when not re-using parts.

Roger that.....don't have a torch, so......enter the mangler


damn thing will turn around and bite you quicker than a snake.
I started with this


and cut the bolts holding the wishbone to the axle frame........making up names as I go.



Once I cut the 4 u-bolt and 4 bracket bolts I tipped it up to get a better angle on the big boys.



Mangler vs Rusty Bolt



Cutting down is definitely the way to go.....






Flip sides and repeat



grind for 10 minutes and your done....sorta



I took the old bunks off the original trailer and placed them where the stringers are.....approximatley 38" apart.









4 inches is the rise from the keel to the approximate center of stringer.



A couple of concerns-comments I have is that the frame that I need to attach the bunk brackets and keel rollers to is a L shape frame. I haven't seen anything that will clamp or bolt around the frame......guess I will have to drill and attach. This other question I have is how high off the ground should the keel be when on the trailer? I'd like to keep it as low as the fenders will allow......I will more than likely have to raise it to clear the fenders......whats a safe margin? 

[RickK]

Quick conversion.
Look at the profile drawing in this link http://www.classicaquasport.com/gallery/showphoto.php?photo=2727&title=as-19-6-introductory&cat=542
Find the chine at the rear of the boat in the drawing and follow it forward and notice that the hull bottom right in the start of the "prow" actually drops down a little, so the bottom is not parallel to the chine. You need to make sure that the keel in the lowest area of the "prow" will clear the trailer and any cross beams.
Here is a pic of my 170 and you can see what I mean, I hope
[img][/http://i36.photobucket.com/albums/e19/rkins/ProfileOfBoth.jpgimg]

In this datasheet there are two line drawings at the bottom. Look at the right-hand one and you can see a little difference in parallel on my 230.
So check your 196 and I think you'll see a drop of the keel making it deeper than at the back of the boat.

[jfret]

Thanks Rick, and BTW I've spent hours reading through your 170 Rebuild thread.....so much information that I will use when I get back on the 196 rebuild......thanks again. 

[RickK]

DOH!! Don't know why I didn't look in your signature for your boat and use that as an example.

If you still have the boat on the trailer pull a string flush along the top of the bunk and carry it up toward the bow. Look at the forward 1/3 of your boat and measure from the string to the trailer frame and from the string to the bottom of the hull at the lowest point.  Make sure that the new trailer allows whichever is the largest measurement. You may need taller bunks to accommodate this.

Oh and thanks - hopefully you won't make the same mistakes I did 

[jfret]

Thanks Rick.......I'm think I'm suffering from paralysis from analysis both on the boat and trailer. Anyway I've looked at it enough and it's time to order some hardware.

[RickK]

 

[jfret]

Got the hardware for the bunk conversion and planned on working on fitting the the boat to the trailer this weekend but it's 52 degrees and raining here in Pittsboro NC. So didn't get squat done on the trailer.

[RickK]

It'll go fast when you start.