Boat Lift Bunk Spacing

[Soyboy]

I will be getting a 2019, 307 Freedom early next week. Does anyone know the best spacing for the bunks on a boat lift for a 307 hull?

 

[wspitler]

Grady has a chart that gives the best spacing.

 

[JM321]

Here you go, I got this from Grady last week.

 

[wspitler]

JM321, Do you have the speadsheet or just the png file. The spreadsheet would have more information about buttock as well. Thanks!

 

[JM321]

Try this.

 

[wspitler]

Try this.

Thanks! I had that 2010 pdf, just looking for the updated one that appears to be a spreadsheet with revision history. I can probably get it from Grady.

 

[JM321]

That’s weird, I just got the email from GW last week and it shows updated 2020. Let me look again.

 

[JM321]

 

[JM321]

I’m having trouble with the PDF that was in Word. I’m an Apple guy, so that’s a screenshot of what I just got. Sorry for the format.

 

[wspitler]

I’m having trouble with the PDF that was in Word. I’m an Apple guy, so that’s a screenshot of what I just got. Sorry for the format.

Thanks for trying! It shows an XLS file name, but when I download it's a png file.

 

[seasick]

I’m having trouble with the PDF that was in Word. I’m an Apple guy, so that’s a screenshot of what I just got. Sorry for the format.

It was a png file. I got to view it two different ways. You can open it with windows Photos app or if it lets you, use the Save Image option in the file manager and it will save a jpeg file format which you can open using various apps. The challenge for me was to get the image big enough for my old eyes to be able to read when I printed it.

 

[Last Stop]

I have just had my lift completed for 307. The charts give two options for the Bunk locations and sizes. Which is better and why? I’m tending towards the wider bunk setup ie 25 3/8” from the center. The photo shows the narrow 12 3/8” from center setup as initially done by the lift installer.

Any advice and Possible photos would be appreciated.

 

[DennisG01]

Last Stop... do a quick measurement - from the picture it looks like if you slide the bunks out much further that the keel will hit the lift crossbar. Measure the distance from the keel to the crossbar ("X"). Now, take a straight edge off one of the bunks, held horizontally level. Next, use a ruler or tape held perpendicular to this straight edge at "X". The spot where the ruler hits the hull is the spot where the hull will contact the crossbar at the same time the boat sits on the bunks if moves to the new position. Move the bunks a few inches inward of that point. But if turns out to be closer to the middle of the point between the keel and the strake, I'd leave it where it is. I suspect that in order for you to get the bunks to the first set of strakes that you'll have to increase the height of the bunks.

 

[Last Stop]

Last Stop... do a quick measurement - from the picture it looks like if you slide the bunks out much further that the keel will hit the lift crossbar. Measure the distance from the keel to the crossbar ("X"). Now, take a straight edge off one of the bunks, held horizontally level. Next, use a ruler or tape held perpendicular to this straight edge at "X". The spot where the ruler hits the hull is the spot where the hull will contact the crossbar at the same time the boat sits on the bunks if moves to the new position. Move the bunks a few inches inward of that point. But if turns out to be closer to the middle of the point between the keel and the strake, I'd leave it where it is. I suspect that in order for you to get the bunks to the first set of strakes that you'll have to increase the height of the bunks.

Thanks for the response. I’m happy to have the heights of the bunks increased to accommodate the wider spacing. Grady White says the two options will line up the bunks with the boats stringers. Will wider bunks make the boat more stable on the lift? Make docking easier?

 

[DennisG01]

Yes, lining up with the stringers is important - hence my comment above about keepign things were they are as opposed to more "in the middle". Down towards the keel is still plenty strong.

Wider bunks... not really. It's just two different ways to do the same thing. If you go with wide bunks, then you'll position them on one side of the strake or the other - not on the horizontal surface of the strake.