Correct Position for support stands & keel Blocks
- Thread starter daddy d
- Start date
- Oct 6, 2006
- 12,155
- Boat Info
- 1996 450DA
- Engines
- 3116 Caterpillars
The keel blocks support the weight; the stands are set just firm enough to keep the hull steady and should not be set tight enough to lift the boat.
I used 4 keel blocks on my 390.......one under the transom, one at each sling mark and the last one under the front of the boat about as far forward of the front sling marks as the one under the transom is aft of the back sling mark. Then you need 4 stands on each side of the boat. Adjust the stands after 24 hours, then again at 48 hours then every other day unless you get a lot of rain.
I used 4 keel blocks on my 390.......one under the transom, one at each sling mark and the last one under the front of the boat about as far forward of the front sling marks as the one under the transom is aft of the back sling mark. Then you need 4 stands on each side of the boat. Adjust the stands after 24 hours, then again at 48 hours then every other day unless you get a lot of rain.
northern
Well-Known Member
- Jan 17, 2007
- 3,526
- Boat Info
- 380 Aft Cabin 1989 Charts Timezero radar Furuno
- Engines
- Twin 454 strait shaft
I went through this and got lots of advice. Finally SeaRay wrote me and said they do not recommed blocks. Thet recommend a cradle. My boat is different than your but if you email SeaRay at
SJones@searay.com
They should be able to help you.
Rule of thumb from all the answers was one block every 10 feet of hull length (a 40 foot boat needs 5 blocks) and do not put one at any hard point IE at the keel to the transum as this is a weak point.
SJones@searay.com
They should be able to help you.
Rule of thumb from all the answers was one block every 10 feet of hull length (a 40 foot boat needs 5 blocks) and do not put one at any hard point IE at the keel to the transum as this is a weak point.
- Oct 6, 2006
- 12,155
- Boat Info
- 1996 450DA
- Engines
- 3116 Caterpillars
Cradles are no longer available from Sea Ray. When they were in 1998, a friend bought one fro a 370DA. The cost was $4800 + $1800 freight. Not a realistic approach to a common problem. So that leaves you having to have one custom made locally. The other problem is what do you do with it when the boat isn't on the cradle? It will be as big as a 30 ft boat so expect to pay the yard for storing it for you. In a perfect world a cradle is the best approach, but in a real application, they are not practical.
The 390EC has no keel but has a flat running surface at the transom. We've blocked Sea Rays up since 1988 and found no "hard points" to avoid anywhere along the bottom where you would position blocks. I also take a minor issue with the 10 ft rule of thumb. The stem extends well back at an angle on most Sea Rays so on a 390EC, using 4 blocks is going to net something less than 10 ft between the blocks. 4 blocks is adequate.
The 390EC has no keel but has a flat running surface at the transom. We've blocked Sea Rays up since 1988 and found no "hard points" to avoid anywhere along the bottom where you would position blocks. I also take a minor issue with the 10 ft rule of thumb. The stem extends well back at an angle on most Sea Rays so on a 390EC, using 4 blocks is going to net something less than 10 ft between the blocks. 4 blocks is adequate.
Searaybio270
Active Member
- Jul 8, 2010
- 1,058
- Boat Info
- 1996 EC, Garmin 3210, Dinghy - Seadoo Jet boat with twin 85 horse. Fun and Fast.
- Engines
- 7.4 MC 360 HP each
Westerbeke 7KW
Frank,
I have a 400EC. Could I build three cradles? Placing them front, middle and rear. Then stack them when I launch the boat. Just curious. I am always trying to think outside the box. Thanks.
I have a 400EC. Could I build three cradles? Placing them front, middle and rear. Then stack them when I launch the boat. Just curious. I am always trying to think outside the box. Thanks.
northern
Well-Known Member
- Jan 17, 2007
- 3,526
- Boat Info
- 380 Aft Cabin 1989 Charts Timezero radar Furuno
- Engines
- Twin 454 strait shaft
Frank
If you are interested in a craddle design based on what SeaRay sent me I could build one from the drawing they sent me. As noted the yard would probably and a fee to store it. Best advice I got was to draw up a blocking and support plan and give it to the yard before they lift your boat with a note on the plan that if they feel it is not adquet they can modify it and they are responsible for any damage to the boat because of improper blocking. After a yard damaged my boat by not blocking it correctly I am very careful how my boat is lifted and blocked. I feel with to many blocks and side supports than not enough. The yard fixed my boat. My insurance company said it was the yard they would have sent it to to be fixed. The job was well done. Make sure you watch them block your boat.
If you are interested in a craddle design based on what SeaRay sent me I could build one from the drawing they sent me. As noted the yard would probably and a fee to store it. Best advice I got was to draw up a blocking and support plan and give it to the yard before they lift your boat with a note on the plan that if they feel it is not adquet they can modify it and they are responsible for any damage to the boat because of improper blocking. After a yard damaged my boat by not blocking it correctly I am very careful how my boat is lifted and blocked. I feel with to many blocks and side supports than not enough. The yard fixed my boat. My insurance company said it was the yard they would have sent it to to be fixed. The job was well done. Make sure you watch them block your boat.