Shop Cradle for the C-22, "How To"!

[CloudDiver]

I got a request from a member for more details on the shop cradle I built for my C22, so here are some more pictures and details of materials and measurements.

Notes;
- I built this to hold the C-22 INVERTED. The design can be easily modified to hold the hull upright as well. Heck, it may work just the way it is without modification but I haven't tried. Wouldn't that be a hoot? The big thing to remember if you try this, the aft portion of the hull is thin and flexible. The aft cradle section would need to be modified to spread the load as much as possible to avoid point loading and cracking the GRP.

-These dimensions (especially where the pads land on fore deck and in cockpit) are for my 1982 C22... So if you have a 1986 or later C22 you may have to check and possibly make changes.

- You can use heavier lumber if you like. Just don't try going lighter with all 2x4 construction... trust me. It gets too flexible in key areas. You will see how I added strength in key areas.

- Its not very expensive even if you buy all new lumber. I don't remember exactly but I know I spent only around $100 on the first load of lumber, I added a little more later so it was only around $120 max.

- It is a 3 part design so it is easily disassembled and stored or moved in a pick-up truck. If you nail or screw the whole thing together you are stuck with a big, awkward thing that will be a pain to deal with when the boat is back on the trailer. The Fwd and Aft sections simply bolt to the middle section with 3/8" grade 5 bolts. It takes just 10 minutes and a helper to put together or take apart.

- You need GOOD quality, HEAVY DUTY caster wheels with ball bearings! Its pretty heavy, probably around 1300 to 1500 pounds of boat on the cradle with the keel off, even more if the keel is on! With good caster wheels, on level ground, one person can roll and swing this around with the boat on it.

 

[CloudDiver]

Materials List

Lumber
Should be as straight and defect free as you can find, but standard construction lumber from the big box store is all you need. Make sure its dry! A few of mine were still very wet and thats not good!

2" x 6" x 12' qty 3
2" x 4" x 12' qty 8
1/2" Plywood (scrap) or a small 2 x 4 sheet if have to buy new

Hardware
Box of 2 & 1/2 inch wood screws
Box of 1 inch wood screws

3/8 grade 5 bolts, washers and nuts
5/16 grade 5 bolts, washers and nuts (for caster wheels)

3/8" x 6" stainless eye bolts (2) with fender washers and 2 extra nuts

4 HD Caster Wheels

 

[CloudDiver]

AFT Support

The FWD and AFT sections are mostly identical, the big difference is how high the vertical supports are. On the AFT section they are taller so they reach into the cockpit and rest on the seats just forward of the cockpit hatches.

Note: if you build the cradle for sitting the hull upright the aft supports will NOT be this tall.

With one of the 2 x 6 x 12, cut 2 pieces at 60 inches. Screw these together in a "T"... This is the base of the stand.

Cut two more pieces of 2 x 6 at 36 inches each to make the vertical legs. On the ends you will cut a slight angle, I'm not sure exactly what that angle is. When I had the boat Inverted I used a carpenters adjustable angle finder against the vertical support which was already screwed in place. Its probably somewhere around 3 to 5 degrees (I Think).

Cut two pieces of 2 x 4 to a similar length and match the angle at the top, but overall this piece is shorter so the pad screws to the top of both as shown in the pic.

There are two important measurements to get correct here. When you screw in the 2 x 4's that are the inboard vertical supports you should have 26 inches between the inside edges. This is where the center section of the cradle will rest and bolt to.

When you screw the 2 x 6 vertical supports, which are outboard, you need enough room on the outboard edge of the base so that the bolts for the caster wheels can go through, see pic.

 

[CloudDiver]

Diagonal bracing

Its important to use diagonal bracing as shown in the pics, this adds a great deal of strength in the structure for both pushing and pulling forces. Do not leave these out!

The two diagonals you see in the above pic started out life as a simple single cross support between all the vertical legs. I changed it to the two diagonal braces in a V shape as you see in the pic because a cross support blocked entry into the boat when inverted.

In any case, I always used a single screw to tack things into place first, make sure everything was squared up before I drove in additional screws. Nails can be substituted for screws in these subsections that do not come apart.

The dimensions for the diagonals are just on the fly. I just cut 45's and made sure they were high enough on the verticals to give strength by reaching at least roughly center on both dimensions.

Notice also how I use the plates of plywood to support the sections in the middle where the diagonals butt joint to the base. This is critical, do not leave this out. This is also what the 1.25 inch screws are for.

The eye bolts were added as shown to provide a 'tow point'. My driveway is sloped so I was using my electric winch to roll the cradle in and out of the shop.

 

[CloudDiver]

FWD Support

The forward support is built practically the same as the aft support. The big difference is that the vertical legs are not as tall. Here, the outside edge of the 2 x 6 is only 31 & 1/2 inches. The angle is a little more steep, and the support pads are made from 2 x 6 that are about 12 inches long. These were designed to rest on the deck between the toe rail and the forward hatch where I felt it was the strongest.

Otherwise this section is built practically identical to the rear section;

 

[CloudDiver]

The Middle Section

I suggest building the two end sections first and then building the middle section last. I built mine "in place" when the hull was inverted on regular Brownell stands, so I didn't even know what the middle section was going to end up being until I placed the two end sections.

Technically, you could build the middle section first (If you trust my measurements, lol!)

The mid section is where you could add strength by using all 2 x 6 instead of 2 x 4's like I did. Its a good idea I think, but my design held up fine with little flex and dozens of trips in and out of the shop, even a few 180 degree turns.

The long 2 x 4's are 140 inches, cut 4. Use two of them as side rails and then cut 5 cross supports, about 22 & 15/16 inches each... What you want is 25 & 7/8 inches to the outside edges. This gives 1/16 inch of wiggle room for each end to 'socket' into each end support between the inboard vertical legs.

Once the main 'ladder' is built and square, use the additional two 140 icy 2 x 4's to screw down on the top in an L fashion as shown in the pic, this takes massive flex out of the center section. If you decide to use 2 x 6 lumber here you probably don't need to do this, but I would suggest plywood triangles across the butt joints and in the corners.

 

[CloudDiver]

Once you have the 3 sections constructed you the socket the middle section to the two end sections and secure them with the 3/8" bolts, I used 3 on each end. Once together the overall length of the cradle is around 12 feet. Then you want to add the diagonal supports that go from center on the middle to each end. Two bolts on each one just off center of the middle, one can be removed while the other stays in as a pivot for storage. The ends that meet the end sections will butt joint to the vertical support, so I use one screw just to secure it and then add a small triangle of plywood to give it real strength.

 

[CloudDiver]

OK, so how do I get my boat off the trailer and on THIS?!

If you want to use a cradle like this you need to plan ahead about how you will get your hull off the trailer and then onto the cradle, then back again.

First, there are several posts in the forum covering how to get the boat off the trailer and then onto any variety of stands or supports. There are 100 ways to skin a cat.

For all my lifts I used a combination of standard boat stands, two cherry pickers (engine lifts), and an electric winch with a block mounted in my shop ceiling. It can be done in doors or out doors, you just have to change up equipment depending on your situation.

Whatever method you choose, the cradle is designed to be assembled in parts under the boat in case you don't have room to roll it in from the side or front or back.

There are too many variables at play to give an overview because every situation is different. If you have specific questions about how to pull the boat off the trailer and onto a cradle you can ask here but you need to provide specific details;
Are you indoors or outdoors?
Type of floor or ground?
What type of equipment do you have or can borrow/rent?
Do you intend to flip (invert) the hull for a bottom job, or leave it upright?

 

[CloudDiver]

Thats pretty much it... I know there are a few details and measurements I may not have included, but they are easy to figure out. (Like the length if the bolts, I think they were all 5 inches)

Anyway, ask any questions you like and I hope this helpful!

 

[Alexsip]

Thanks cloud, lot of details. Appreciate the help