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dmede
08-08-2018, 04:11 PM
I have my 18' Sea Skiff on a rolling building platform, which you just barely see under the boat in the image below. It's a 2x6 rectangular frame with cross pieces and two cradles for holding the hull. I leveled it the best I could when setting up initially to plank but my garage floor and the driveway leading to it are not at all level, lots of dips and cracks. As I roll the frame around I can see the hull twist a little here and there. I'm just getting to seat layout and glueing down the floor panels. I want to relevel the frame before I do any of that work, but not sure how.

I had the idea that I could somehow attach large bolts to each corner to adjust up and down to level the frame wherever I have it rolled to. But not sure how to implement that. Has anybody here done anything similar? Don't want to rely on wedges and shims under the wheels.

https://i.pinimg.com/originals/8d/ad/f6/8dadf65aeec0042156dca22c6c86f416.jpg

Peerie Maa
08-08-2018, 04:20 PM
Weld the equivalent nuts onto plates that you can screw to the bottom or sides of the frame. Then you can jack up to your hearts content with long enough bolts inserted so that the bolt head is on the floor.

mmd
08-08-2018, 04:56 PM
Nick's suggestion is the way I would go, except that I would add a locking nut between the bolt head and nut welded to the angle.

Don't even need to weld the nuts, though, if finding a welder to do the task is problematic. Make up four short pieces of angle bar with a 1/2" hole thru one leg. Screw or thru-bolt the angle bars to the four corners of the cradle frame, hole-side on the top. Get four 1/2-in bolts that are 2" longer that the distance from the angle leg to the floor, plus twelve nuts. Thread two nuts on each bolt all the way to the head. Insert a bolt in each angle piece up from below (so the head becomes the 'foot', as Nick mentions above) then thread on one more nut. With all nuts slacked off, snug up then adjust the upper underside nut on each bolt to raise the cradle (this is a two-wrench operation; one on the adjusting nut and one holding the bolt head from turning). When level, snug lower underside nut and upper nut to the angle piece to lock the adjustment in place.

Don't skimp on the size of the bolts, though. They don't just support the weight of the cradle, boat, you, tools, wood, etc.; they also have to resist sideways forces when you lean on the boat, bump it, etc., and the stresses on the 'legs' can be quite high. You wouldn't want to bend one, and threaded rod bends quite readily. Go big or go home.

Peerie Maa
08-08-2018, 05:02 PM
Levelling might be easier with a fifth leg midway between one pair. Then level on three legs (always easier, think camera tripod) before snugging up the last two.

swoody126
08-08-2018, 05:08 PM
whichever way you end up doing it IT IS WORTH THE TIME SPENT

having a level platform sure makes jobs easier

sw

mmd
08-08-2018, 05:12 PM
True, Nick, but couldn't one accomplish that by merely setting diagonally-opposing legs high enough so that the cradle is 'tippy' upon them, then levelling incorporating a third leg, and finally setting the fourth to stabilize the entire unit?

Peerie Maa
08-08-2018, 05:15 PM
True, Nick, but couldn't one accomplish that by merely setting diagonally-opposing legs high enough so that the cradle is 'tippy' upon them, then levelling incorporating a third leg, and finally setting the fourth to stabilize the entire unit?

True dat.

Gib Etheridge
08-08-2018, 06:57 PM
Edge drill 4 scraps of 2x4 or 2x6 with a 3/8 bit. Screw a 1/2' lag bolt part way into each hole. Apply the 4 pieces to the 4 corners of the frame with deck screws with the heads of the lags on the concrete.

Use a wrench to screw the lags in and out to get the frame where you want it. You might have to put some weight in the boat or spring poles down from above for this to work.

Lock it in place with spring poles down from the ceiling or roof framing.

OR...

Level the transom with a shim under 1 wheel or a block under one corner of the frame. Put a piece of plywood or some 2x scraps over the well or across the sheer at the transom and weight it down but good. 150 pounds of scrap gold will do that nicely, or 160 pounds of lead (lead is not as dense as gold so you need more). Clamp a vertical 2x4 to the stem and swing it back and forth until the stem is plumb then fasten it to the collar ties.

Canoeyawl
08-08-2018, 11:59 PM
Take a look here

https://www.mcmaster.com/#mounting-feet/=1e2qkbe

Ralphie Boy
08-09-2018, 08:43 AM
Hi dmede,

When I built a lapstrake canoe I also used a strong back which had casters, since my single car garage was so small. What I did was to level the jig in one position, and then mark the position of each caster on the floor with tape. Then, if I needed the jig to be level I could just return it to its original position. Good luck!

Ralphie

Yeadon
08-09-2018, 10:40 AM
I don't think you'll ever get all the wheels perfect on the floor. I'd focus on making your roll-around cart as stout as possible so it doesn't flex when moved. That's probably best-case scenario.

jpatrick
08-09-2018, 10:51 AM
Blocks and shims are the perfect solution. Don't put them under the wheels. Put them under the 2x6 frame material so that the wheels are slightly lifted from the floor. This will be as stable as adjustable bolts, you can do it now, and you probably have all the material at hand.

Jeff

dmede
08-09-2018, 02:49 PM
Take a look here

https://www.mcmaster.com/#mounting-feet/=1e2qkbe

Just what I needed. Found similar units on Amazon. My strongback frame is taller than the reach if these but I'm guessing I can sub my own longer bolts or add blocks or something. Thanks!

Paul Schweiss
08-09-2018, 07:24 PM
Go to www.mcmaster.com and look up ‘leveling mounts with mounting bracket’

I used these for my router table cabinet that doubles as a run-off table for my table saw. My garage floor is quite in-even, but these work great.

I also found some casters for my jointer-planer that have an adjusting foot to lock them in place, quite compact.