Where to put blocks under boat

[kaliona]

I've read the many posts on how to raise and block up your boat in order to pull the trailer out. My questions are:
1) Does it matter "where" you put the blocks under the boat? I plan on using railroad ties cut to about 16" lengths and stacked as needed between the strakes (I think that's what those fins are called).
2) Are 16" long blocks long enough to distribute the load?
3) Do the blocks have to be cut to match the deadrise of the hull?
4) Should I be as close to the outside edges of the bottom as possible? Or closer to the centerline of the boat?

I don't know how hulls are constructed and I keep picturing the blocks breaking right through the hull like your foot would break through a gyp board ceiling if you stepped between the wood joists.
If it matters I have a 17' 1978 Caravelle I/O fiberglass bow rider.

 

[triumphrick]

Re: Where to put blocks under boat

Some answers....

1) Yes, should be supported at or very near the transom as possible. Alos near the bow, around the front 1/3 of the boat. (Worked for me)

2) Yes, should work fine..make sure as much of the weight is on the keel, not the sides. The keel is laid up the heaviest with glass, the sides are quite thin.

3) Mine were...to the best they could be. Actually I used discarded road drain pipes..16" - 18" pvc. Kept them very short and used a sawzall to shape them.

4) Definitely as close to the transom edge as safely possible without a potential of tipping out, right down the centerline. I centered my front support under the most weight, center console...

5) Good luck!

 

[Bondo]

Re: Where to put blocks under boat

4) Should I be as close to the outside edges of the bottom as possible? Or closer to the centerline of the boat?

Ayuh,... Basically,... You Absolutely Must use 3 stacks of blocking,...

1 each, at the outer most corners of the Transom....(at the outer chines is Perfect)
And the other 1 under the Keel, 2/3rds the way forward of the transom, just before it turns sharply Up to the bow...

If you want to add more stacks in other places,.. Fine...
But those 3 points are Absolutely Necessary...

 

[jeeperman]

Re: Where to put blocks under boat

I always over do it.
I did like Bond-O describes but then I used a 2x4 horizontally to nail the two transom support stacks together. I had this vision that the stacks would get pushed apart by the v-hull pushing down.
I had a ten foot 4x6 so i used that on top of two more stacks up front that were far enough apart to clear the trailer.

 

[MRS]

Re: Where to put blocks under boat

I don't know how hulls are constructed and I keep picturing the blocks breaking right through the hull like your foot would break through a gyp board ceiling if you stepped between the wood joists.
If it matters I have a 17' 1978 Caravelle I/O fiberglass bow rider.

This is what I did I was real worried when I started but if you take your time it is not bad at all. I did it by my self would have been better if I had help but now if I have to do by my self not a problem. Check this out hope it works first time trying to post a link.
http://forums.iboats.com/showpost.php?p=2406449&postcount=6

 

[kaliona]

Re: Where to put blocks under boat

Geez that looks spooky! But it looks like it worked for you.
Has anyone ever had a boat fall off the blocks? What would you do then, besides cry and cuss?

 

[slasmith1]

Re: Where to put blocks under boat

Here is how the pro's at the boat yard do it.

all of the weight is on the keel blocks the stands just keep it from tipping. (this boat weighs about 16000 lbs as rigged)

 

[smokeonthewater]

Re: Where to put blocks under boat

MRS
jack stands can be a little wobbly but what concerns me the most is that you chose to do it under the car port..... I can understand why, but you did increase the danger for yourself by creating pinchpoints.... harder for you to escape if it starts to go.... you could build cribbing up to replace the jack stands but I think I'd leave it alone and just work on putting the trailer back when it's done..... Just be very aware of the danger and try to shelter your self with the trailer as much as possible while putting it back under.
When I was backing under my 28'er I had an rv inches behind it with the idea that if it started to push back it would hit the rv and cause minimal damage instead of falling off the stands
good luck

 

[MRS]

Re: Where to put blocks under boat

The boat is very solid on the jack stands plus I have a 12 ton bottle jack in the center on the transom. When I did remove the trailer I removed it by hand (people power) when I lift the bow with a 3ton floor jack maybe 2 3/4 inches the trailer bunk boards do not touch the boat. I know how it looks but really is very solid I will roll the trailer back in by hand also. I just painted trailer this last weekend and am doing bunk boards this week so this weekend will put back on trailer and post photos. Plus there is alot more room on the left side of the carport (boatport) than it looks like......