bertram31.com

Gents,

I have just purchased a home with a four point boat lift. Soon, gone are the days when I spend 1 hour/month beneath the boat, cleaning and scrubbing!

The house came with a four point lift similar to this one...



The manufacturer is recommending either the fore/aft bunk system you see above or 4 pads (think screw jacks, like one sees in a boat yard).

My only hesitation is that either arrangement - fore/aft or pads - runs counter to what I see at boat yard. A majority of the boat's weight rests on the centerline (one under engine bulkhead), and screw jacks are used for lateral stability. And when transporting a boat, that is also how a boat is set.

I told the lift manufacturer that I wanted to rest the centerline on the horizontal I beams, and use 4 pads on the side for lateral stability - just like you do in a yard. The manuf gave me a LOT of push back. The old "we have never done it that way before" and "we have never had anyone complain about the bunk system."

Am I over thinking this and should I go with their recommendation? Interested to hear from others that have boat lifts...

Thanks,

Bill

Bill,

I have a lift just like the one you pictured. I made some adjustments to the bunks that the boat sat on and I mistakenly allowed the centerline to rest on the rear horizontal I beam. Just the wind moving the lift back and forth allowed the I beam to start wearing a hole through the gel coat on the bottom. I suppose if you insulated the beam with carpet, it wouldn't be too bad, but the lifts around here all are adjusted to keep the boat off the steel or aluminum horizontal I beams for that reason.

I moved the bunks towards one another until the boat only rested on them.

Dick

Thanks Dick.

Were you using the fore/aft bunks like the ones pictured or the 4 pad system?

Bill

Just like the one pictured, ecxcept mine needs a good paint job.

Dick

I keep my boat on a similiar lift except there is a 3x12 horizontal plank that ties the fore and aft bunks tied together, that the keel ,so to speak,sets on and a carpeted bunk on both sides of this center plank, the bunks are probably 32" apart, I also have a 38000# rybovich which has been on this same system for 5 years and no problems, there are lots of boat lift dudes that will accomadate your needs, go on Neptune boat lifts site , they have a unique stern centering arrangement that just works , no matter how much wind or current is rippin, u purchase a lift to protect the boat, consider this feature

of the many boat lifts I have seen, no one uses screw jacks, u certainly would not want to miss the target location and put a screw jack , with there small footprint ,thru the hull or trim tab etc

I am using only two bunks right over inside stringers. Purchased aluminum beams, precut to 23 degrees with rubber pad rivited on.
Didn't want any flotation.

[img][img]http://i246.photobucket.com/albums/gg10 ... 010143.jpg[/img][/img]

Thanks Andre. Is the centerline resting on the lateral beams? Or, is all the weight on the two bunks right over inside stringers?

Bill

All weight is on bunks- none on beam.

nice set up andre'.

andre
i like your a/c on the pole

Dat be a Looooosiana air conditna.

So dumb question. Can putting the boat up and down in the lift, over time; affect the saft alignment?

not a dumb question brewster .i cannot close the door to the cabin after i remove from water .shafts move inward out of water . i have every conceivable boatyard blocking/cradles known to man and it still occurs.

Thats why I asked. The last two years when I went on the hard for the winter I could not close my door. I dont care about the door. I was thinking what it did to the shaft alignment.Maybe I should check it in the spring two days after launch. See if its still OK.

after 11 years of trying portable wide cradle/ permanent i beam strake supported type cradle, keel support with 4 straight worm gear supports and two large angle worm gear supports at bow angle.old style angle wooden supports with cement blocks with wood supporting keel .wooden bunks with steel supports along entire lenth of strakes from bow to stern . lets see have i left out any other method?? the best on land support is three short style cradles with weight equally distributed. supporting boat within three feet on either side of keel . for safety sakes four portable worm style supports on either side of chine at stern and 6 feet in from bow . they are just touching with no pressure . i make boat dead level and cabin door closes as well as no "creaking" when boat is set down off travel lift.

bob lico wrote:after 11 years of trying portable wide cradle/ permanent i beam strake supported type cradle, keel support with 4 straight worm gear supports and two large angle worm gear supports at bow angle.old style angle wooden supports with cement blocks with wood supporting keel .wooden bunks with steel supports along entire lenth of strakes from bow to stern . lets see have i left out any other method?? the best on land support is three short style cradles with weight equally distributed. supporting boat within three feet on either side of keel . for safety sakes four portable worm style supports on either side of chine at stern and 6 feet in from bow . they are just touching with no pressure . i make boat dead level and cabin door closes as well as no "creaking" when boat is set down off travel lift.

Bob...wouldn't it be easier to just setup a small pool inside and float the boat

carl i gave it some through ! the water would go bad so i had to put the boat away for winter with weight distributed along both keel line and inner most strakes the way it would in the water. i do it on a " off day" with yard help available. the boat has to sit in the portable cradle with the weight equally distributed between the shimed keel and the pads touching exactly at same time this is done three times . the boat is movable because the cradles are on wheels . the worm style supports are just safety.

Bob...you can't fill with water!! Bertram Juice of course..

bob
just make your pond in your back yard bigger, and drop her in by helicopter

I dunno, I think one of them endless pools about 32' x 15' in a covered, climate controlled bldg...
She'll sit naturally on her bottom, in the wet.
You've got the constant current to keep the algae and insect breeding down, and the bow pointed true.
You've got the mild chlorine and bromine to further eradicate any biological growth in the water.
You can fire up the cummins' at will during winter.

Maybe put a little sauna in the corner of the bldg... you know, do a little grinding, go sit in the sauna, jump into the pool, tank test some new secret trolling lures...

It's clearly a win/win situation, and an all around great way to enjoy the boat while there's 12" of snow on the ground.

spent 20 yrs shoring up boats for the winter season, rule was block the keel every 10 ft, hence a 31 would need 3 blockings points on the keel, we also would shore up on the chine areas .in the same location as the blocking longitudinally, with 4x4's or screw jacks in latter years, we did this for wood and fiberglass boats and yachts, doors always closed and we did not want to realign the engines at our expense, again my 31 will be set on a 3x12 plank between the lifting bunks, which will support a considerable stretch of keel area and only balance the load at the chine, you are getting the strength of the entire vertical hull compressing on the chine area vs setting on stringers supported areas, the boat lift guy used the 3 legged milk stool as the analogy , any more outboard supports would be unnecessary, the boat was shored up like this when we aligned the engines and had not seen water 4 five years, engines aligned to.004 on the beach and after 5 wet days they had not moved, maybe .001 at the most, my 42' boat is set up this way on a boat lift and the doors always close and we don't have alignment problems

marlin strictly off the record what is the hull number of your 42' rybo. my friend has the book with his hull# 25 in it . book was $700.00 and absolutly fantastic.

bob--i am still trying to get through my copy---love the history---the design and simplicity of the early boats have influenced the changes i have made to my boat.

i have never seen a book like that one in my life . old fashion boat building to current 75' battle wagon . what can i say gold leaf edges on pages ,a work of art just like the boat. both the rybovich and my bertram get this special attention of on land storage in the maintenace building.next year i will put in pool as buju sugested.

Andre,
Out of the water and covered. Damn, I'm so jealous. If I could do that the owner of the yard where I haul annually would commit suicide,
I fitting end.