Underskinning material??

[ToonGuy]

I have used #10, standard hex head SS self tappers with no issues at all. I just worked on one of the boats I built 2 years ago, and I gave it a once over for the guy and only found 1 screw with a missing head. Didn't find a single one that backed or stripped out. And that guy uses his toon hard. You can find boxes of 100 on line for like $8 bucks delivered to your door.

I've worked on many boats that use standard 3/16 rivets, and yes you do see a few get the heads poped off from time to time but nothing that would cause a failure.

I'm not saying they're aren't better (and more expensive) ways of doing it, just what has worked fine for me.

[Themacdadt]

I have used #10, standard hex head SS self tappers with no issues at all. I just worked on one of the boats I built 2 years ago, and I gave it a once over for the guy and only found 1 screw with a missing head. Didn't find a single one that backed or stripped out. And that guy uses his toon hard. You can find boxes of 100 on line for like $8 bucks delivered to your door.

I've worked on many boats that use standard 3/16 rivets, and yes you do see a few get the heads poped off from time to time but nothing that would cause a failure.

I'm not saying they're aren't better (and more expensive) ways of doing it, just what has worked fine for me.

Do they not make alluminum self tappers? Just wondering cause I thought you should not mix metals.

[teecro]

.... Do they not make alluminum self tappers? Just wondering cause I thought you should not mix metals.

Not much of a real problem when your talking about mixing alum and stainless... Take a look around any toon and you will see a lot of mixed metals such as deck fasteners, various nuts and bolts etc...

[ToonGuy]

.... Do they not make alluminum self tappers? Just wondering cause I thought you should not mix metals.

Not much of a real problem when your talking about mixing alum and stainless... Take a look around any toon and you will see a lot of mixed metals such as deck fasteners, various nuts and bolts etc...

X2

[STEVEBRENDA]

I used self tapping screws, with a rubber or nylon washer on our last boat. After 3 years, only one screw had come out.

Much easier to install than drilling and popping each rivet in place.

[Themacdadt]

I have used #10, standard hex head SS self tappers with no issues at all. I just worked on one of the boats I built 2 years ago, and I gave it a once over for the guy and only found 1 screw with a missing head. Didn't find a single one that backed or stripped out. And that guy uses his toon hard. You can find boxes of 100 on line for like $8 bucks delivered to your door.

I've worked on many boats that use standard 3/16 rivets, and yes you do see a few get the heads poped off from time to time but nothing that would cause a failure.

I'm not saying they're aren't better (and more expensive) ways of doing it, just what has worked fine for me.

Any certain thread? Or just look for #10 standard hex head in ss? Didn't know if there is differant threads being that it's 2 .063 sheets that are overlapping and going through what I think is 1/4 inch cross beams for a total of less than a half inch. Seems like I would need like a fine thread. Do they offer that?

[ToonGuy]

IIRC, the box I have at home are just standard thread (I would consider it corse). I'll check them out tonight. I do know if you have an overlap or a particularly tough one a quick reverse on the gun cleans the thread and they go right in.

[crookedlaker]

I worked on underskinning my boat last night, Still have to put the edge pieces on but ran out of screws
I used the #10 stainless hex head self tappers and they worked good. I originally bought #8 but returned them and bought #10 per Toon Guy recommendation. I used .050 aluminum sheets and went up nicely. I used two 2 x 4 boards about 70" long to hold aluminum in place
rested each end on the top of the pontoons to support the aluminum. it held it up about 1" down from the cross members and made it easy to screw into place. next is to install the Electric Bimini top and to the lake this weekend.
Note the self tappers only come in one thread size, no fine or coarse thread. the ones i used were 3/4" long, I used hex head as they are less prone to stripping compared to Phillips head, especially if you have to remove them.

Mike

[teecro]

... Note the self tappers only come in one thread size, no fine or coarse thread. the ones i used were 3/4" long, I used hex head as they are less prone to stripping compared to Phillips head, especially if you have to remove them.

Actually you can find them in 10-16 and 10-24 thread size.... Check out places such as www.mcmaster.com

[Themacdadt]

Well, got it all done today......looks good. About 5 hours total with a lunch break.

Tips.....I fabricated holders out of wood to hold panels up this is a must unless you have 3 people working on it.

Ss self tappers is the way to go. If you had to drill and rivet every hole it would take three times as long and a lot harder to hold in place and make sure everything aligns.

Knee pads a must.

When you measure DONT forget to compensate for overlapping.

Be prepared for sore shoulders and arms.

Raining this weekend so test drive will probably be next weekend.

Thanks for all the help!!!!

[ToonGuy]

I'm willing to bet you will notice the difference. Every time I take out the in-laws pontoon with a 90hp I can't believe how much I can feel the water hitting the cross members and slowing us down.

[Themacdadt]

Well took her out for the first time after underskinning.

Gained 3 mph
Much better ride
It was very choppy and had no issues.

Underskinning is a must for all of you thinking about it!!

[teecro]

Well took her out for the first time after underskinning.

Gained 3 mph
Much better ride
It was very choppy and had no issues.

Underskinning is a must for all of you thinking about it!!

That's it I'm going to get my skinning done this season.....

[TDJ2591]

Although I used and prefer 3/16" rivets over screws, here are some thoughts on using self-tapping screws.

- Be careful not to overtighten and strip the threads, resulting in screws highly likely to fall out eventually. It is VERY easy to strip the threads in aluminum using a screwgun or drill. Adjust the torque setting on your drill-driver, if it has one, to help prevent overtightening.
- Use fine thread screws if you can find them. The aluminum is thin and you want as many threads biting as possible. I talked with a knowledgeable salesman (also a pontoon owner) at an industrial bolt and screw store. He recommended using fine thread screws in aluminum.
- Use stainless steel screws with neopreme washers. The washers will exert just a little pressure on the screws to help keep them tight.
- Be sure the screws are long enough to have threads extending completely thru the panels and the stringers
- Use plenty of screws. That way, if any fall out it shouldn't make a difference.

Good luck! It is a satisfying and rewarding project.

[Drago]

If you are shopping for stainless fasteners and want to compare with McMaster-Carr, check http://www.manasquanfasteners.com/