12' grunman mod

[russelln114]

Hello guys. I have a 12' grunman that i would like to put a floor in. I wanted to cut the middle bench like bufford did on his. In order to do this i would have to have a floor up 6" from the bottom. If i measured the width correctly it measures 48". Is it possible to put a floor in this boat at that height? Also is this what you call a semi-v boat? I may be measuring this wrong so i included pictures. I don't think i want a deck. If i'm able to do the mod to the middle bench then i will move the seat up closer to the front of the boat and then mount one on the back bench thus changing it from a three seater to a two seater

 

[russelln114]

Two more things i wanted to add. First I determined the floor to be about 5" to compensate for the slight v across the floor. I then added an inch so that if i can do it like buffords i can cut the bench down to within an inch that way i'll have something to screw my brace to. buffords bench came the whole way to the bottom mine doesn't. It's 6" in the middle and then tapers off because of my slight v . Second i measured the boat from top of the rail to top of the rail and it was 54". I enclosed a picture of buffords cutout to show you what i mean. And two pictures of troutman 3000. I know they had john boats but if possible for my boat This is what i want the final product to look like

 

[russelln114]

Does anyone have any input about this?

 

[JMichael]

Yes, that is a semi v hull design. Looking at the way your boat is built, you might be able to get away with removing the middle bench all together but a lot of that will depend on what you plan to do with the boat. Factors like load weight, how fast you run the boat, and how rough the water will be, could make a big difference on doing a mod like that. IMO the only way to know for sure would be to try it and then decide if there is too much flex to run it without some sort of braces.

 

[russelln114]

That would be great if i could just remove the bench. I plan on using the boat on trolling motor only lakes and i'm taking it from a three person down to 2. When i do use the motor it is only a 8hp. Has anyone ever done this with this kind of boat?

 

[jasper60103]

That would be great if i could just remove the bench. I plan on using the boat on trolling motor only lakes and i'm taking it from a three person down to 2. When i do use the motor it is only a 8hp. Has anyone ever done this with this kind of boat?

I never done it, but I came across a mod that may be helpful...
https://theminnowbucket.weebly.com/

 

[russelln114]

That would be great if i could just remove the bench. I plan on using the boat on trolling motor only lakes and i'm taking it from a three person down to 2. When i do use the motor it is only a 8hp. Has anyone ever done this with this kind of boat?

I never done it, but I came across a mod that may be helpful...
https://theminnowbucket.weebly.com/

That mod is for a 14' I have a 12'. I do plan on keeping the two end benches and mabye doing away with the middle one. keep the comments comming.

 

[russelln114]

Ok How about this. In order to keep the structural integrity of the boat can i do this. Follow buffords idea with cutting the middle bench except on my boat i would cut the bench completely out leaving no strips running across then building a brace out of wood securing it to the two remaining sides. That way i can lower the floor down to whatever height i want. It would look like these pictures. Does this seem ok for a brace

 

[JMichael]

Maybe these pics of mine will give you some ideas. This is what the dealer installed for bracing when the boat was new for a completely open floor.

During the rebuild, I took the boat out with all the braces and flooring removed. At 28mph on choppy water, I could see the sides flexing as it bounced. So it doesn't take much in the way of bracing to stiffen one up. If it were my boat, I'd eliminate the middle seat completely, then give it some test runs and decide if I needed any bracing or not. From what you're saying your plans are for the boat, I'm guessing you won't need any. But that's just me and what I would do. I'm not a professional or qualified boat builder. :lol:

 

[russelln114]

Ok now i know that i'm just being a pest. but after looking through all the posts I was wondering if I can mabye do something like this https://www.tinboats.net/forum/viewtopic.php?f=21&t=25530&hilit=grumman. I know that his is 13.5' and mine is only 12' but they look like the same type of boat. mine is rated for 725lbs with 3 people and gear. Please help me for i don't know what the heck i'm doing Thanks

 

[JMichael]

You could do something like that, just on a smaller scale since you'll have less room to work with. Just remember that the smaller your boat is, the more you have to be concerned about becoming top heavy and having stability issues when you raise the decks.