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Underskinning material??
Posted: Fri Apr 10, 2015 12:17 pm
by Themacdadt
I ordered my .063 5052 sheets cut to size today. My next thing is to get hardware so....
I've decided on alluminum rivets( unless there's a reason I shouldnt?) my question is what size rivits and how far of a spacing? And why on that spacing?
All thoughts and experience on this is welcome. Thanks
Ps. Will be buying a air riveter. I don't think they make electric ones.
Re: Underskinning material??
Posted: Fri Apr 10, 2015 3:24 pm
by RcgTexas
Sounds like you have it in hand. I used pop rivets and a manual pop rivet gun on my boat and it has held up nicely. 6 to 8 " is how I spaced mine, with a popped chalk line.
Re: Underskinning material??
Posted: Fri Apr 10, 2015 5:21 pm
by BoatCop
When I get around to doing mine, I plan to use these.
Would be more practical if (when) I have to get to the underside of the deck for wiring or other reasons.
Re: Underskinning material??
Posted: Sat Apr 11, 2015 5:56 am
by Themacdadt
BoatCop wrote:When I get around to doing mine, I plan to use these.
Would be more practical if (when) I have to get to the underside of the deck for wiring or other reasons.
What size? And are they alluminum? Coated with anything?
Re: Underskinning material??
Posted: Sat Apr 11, 2015 8:01 am
by TDJ2591
Based on advice from this forum, I used truss head 3/16" Maga-Lok structural aluminum rivets spaced about every 8". They are much stronger than the inexpensive pop rivets. I popped chalk lines to keep the rows of rivets nice and straight, then drilled and riveted. I bought a pneumatic riveter from Harbor Freight (#93458) for $35 that worked great. If you buy this air riveter, don't disassemble it like I did to add oil as it comes already filled from the factory. If the rivets are not ejecting or not seating correctly in the tool, use the next larger sized nosepiece.
For panels that I wanted removeable, I drilled and tapped and used #10x24 pan head stainless steel screws with neopreme washers (you can use hex heads). I also used medium hold lock-tite on each screw and was careful not to overtighten and strip the threads. Avoid 18 pitch threads or self-tapping sheet metal screws as they can't get enough bite on the thin aluminum and can easily strip or loosen and back out later. I would not use the screws pictured above as they will most likely not hold well enough. The panels will take a beating from the water so you want something that is not likely to become loose. Use rivets!
I could not bend the .063" 5052 aluminum on a 10' manual brake. Be prepared to go to a sheet metal shop if you need to bend anything other than small pieces.
The hardest part for me was aligning the existing bolts that protruded below the cross members. I made templates from 1/4" HDF, then used them to mark and drill the aluminum panels for each bolt location. I also made some T-braces from 2x4s to hold up the panels as I attached them. Underskinning is a 2 person job!
Good luck.
Re: Underskinning material??
Posted: Sat Apr 11, 2015 8:22 am
by TDJ2591
Magna-Lok rivets
Re: Underskinning material??
Posted: Sat Apr 11, 2015 8:25 am
by TDJ2591
Sorry about the gigantic image. I attached the wrong size image.
Re: Underskinning material??
Posted: Sat Apr 11, 2015 10:14 am
by dragonx
I'm blind the larger images are a blast, they tell you more then someone can write.
Re: Underskinning material??
Posted: Sat Apr 11, 2015 12:31 pm
by Themacdadt
Any disputes (from experience)about using self tappers?
Re: Underskinning material??
Posted: Sat Apr 11, 2015 12:47 pm
by Themacdadt
TDJ2591 wrote:Based on advice from this forum, I used truss head 3/16" Maga-Lok structural aluminum rivets spaced about every 8". They are much stronger than the inexpensive pop rivets. I popped chalk lines to keep the rows of rivets nice and straight, then drilled and riveted. I bought a pneumatic riveter from Harbor Freight (#93458) for $35 that worked great. If you buy this air riveter, don't disassemble it like I did to add oil as it comes already filled from the factory. If the rivets are not ejecting or not seating correctly in the tool, use the next larger sized nosepiece.
For panels that I wanted removeable, I drilled and tapped and used #10x24 pan head stainless steel screws with neopreme washers (you can use hex heads). I also used medium hold lock-tite on each screw and was careful not to overtighten and strip the threads. Avoid 18 pitch threads or self-tapping sheet metal screws as they can't get enough bite on the thin aluminum and can easily strip or loosen and back out later. I would not use the screws pictured above as they will most likely not hold well enough. The panels will take a beating from the water so you want something that is not likely to become loose. Use rivets!
I could not bend the .063" 5052 aluminum on a 10' manual brake. Be prepared to go to a sheet metal shop if you need to bend anything other than small pieces.
The hardest part for me was aligning the existing bolts that protruded below the cross members. I made templates from 1/4" HDF, then used them to mark and drill the aluminum panels for each bolt location. I also made some T-braces from 2x4s to hold up the panels as I attached them. Underskinning is a 2 person job!
Good luck.
Wow...those things are expensive!! I would have more in the rivevets than the aluminum..
Do you have a cheaper alternative?
Re: Underskinning material??
Posted: Sat Apr 11, 2015 3:43 pm
by TDJ2591
You are right about being pricey. I paid, I believe, about $.40 each for the rivets but I am totally confident that they are in to stay. They are much stronger than standard rivets. You could try regular 3/16" truss head pop rivets. I just took the advice of others on this forum who are much more knowledgeable than me and went with the Magna-Loks. I cringed at the cost but when I considered how much I have in the boat and how much I continue to spend each outing, the additional cost of the rivets wasn't so bad.
I have read postings of some who used self-tapping screws and had them fall out later.
Re: Underskinning material??
Posted: Sat Apr 11, 2015 4:12 pm
by Themacdadt
TDJ2591 wrote:You are right about being pricey. I paid, I believe, about $.40 each for the rivets but I am totally confident that they are in to stay. They are much stronger than standard rivets. You could try regular 3/16" truss head pop rivets. I just took the advice of others on this forum who are much more knowledgeable than me and went with the Magna-Loks. I cringed at the cost but when I considered how much I have in the boat and how much I continue to spend each outing, the additional cost of the rivets wasn't so bad.
I have read postings of some who used self-tapping screws and had them fall out later.
They are closer to a dollar each now.
Re: Underskinning material??
Posted: Sat Apr 11, 2015 4:47 pm
by TDJ2591
Prices must have skyrocketed since I underskinned my boat last year. Check eBay and Amazon for prices. There may be other brands besides Magno-Lok that aren't as pricey. I found a cheaper price just now on Amazon but it doesn't state the quantity. Be sure to get the correct grip length if you order. They have some #s that have a large grip range but are a little more expensive.
Check this out: MGLT-B6-7 MAGNA-LOK RIVETS 3/16 .187 ALUMINUM/ALUMINUM TRUSS HD GRIP-.214-.437
https://www.amazon.com/dp/B00ED3YLS2/re ... kvb0YBM175
Re: Underskinning material??
Posted: Sat Apr 11, 2015 5:07 pm
by TDJ2591
Check out this site. This is where I bought mine, which are the ones pictured. These have gone down in price since I bought mine. Buy $50 or more and shipping is free.
http://www.rivetstop.com/MGLT-B6-E-MAGN ... B00PFYVT6A
Re: Underskinning material??
Posted: Sun Apr 12, 2015 5:19 pm
by RcgTexas
All I can say about the 3/16 pop rivets I used on my boat is that they were first put on in 1995 when it was originally built. There were some sheet metal screws used as well but when I dismantled the boat for the rebuild the screws were gone, the pop rivets had to be drilled out. that was last year in 2014. They were good enough for me.