trailer bunks

[dennis sullivan]

I may be on the wrong forum, but maybe you can point me in the right direction. anyway, I replaced the bunks on the trailer for my 17 mako.i used regular 4 by 6 from house construction.it seems to me that when I load my boat, drive on, the keel area is now hitting the cross member of the trailer just forward of the axle. it did not do this with the old bunks. my thought is that this wood is too soft and is flexing too much when the boat is loaded.should I just raise the bunks or does it really need a different type of wood? they are set where the old ones were.what type of wood should the bunks be? thanks for any help or guidance capt den

 

[Canopy Locked]

Bunks should not be taking any load - they're simply there to stop the boat tilting - the weight should be taken on the keel rollers - have you got keel rollers?
something like this?

 

[dpb]

Bunks should not be taking any load - they're simply there to stop the boat tilting - the weight should be taken on the keel rollers - have you got keel rollers?
something like this?

Not true if it is an American or American style trailer where the bunks take all the load.
I would imagine that the top of the bunk is simply not high enough, assuming that you have not adjusted anything else, like the bunk spacing.
Mako 17 not heavy so doubt the wood is flexing, not at 6 x 4 anyway.

 

[dennis sullivan]

it has a keel roller in front, nowhere else. I believe the boat comes up on the bunks and not on any other rollers. I replaced the bunks last year but was careful to mark all heights and spacing. would it matter if the wood is not pressure treated, at least for it's strength? I do see a bow in the bunk wood that is on there now, so I think replacement is necessary. just more work than a 71 year old wants to do. it will be a little easier to raise the top of the bunk slightly until we get a little cooler weather. thanks for the help. dennis