screws under foam...

[ax1lla]

Hi all,

I have my boards cut and am ready to put my screws in, glue foam, and wrap upholstery.

However, I am stuck on the first part. I want to put my screws in first so that I don't actually see the head of the screw. I am able to get my hands on the back side to screw in the nut - BUT - how do I do this without the head of the screw spinning? This sounds like such a simple problem, but I am at a loss as to how to accomplish this.

Would using a spiked t-nut help at all? Any advice is greatly appreciated.

Corey

 

[cedarjunki]

Re: screws under foam...

umm, i think your referring to seats and cushions right?

most of mine have had a stove bolt passed through then a nut securing that to the plywood...tightened up snug and sometimes countersunk...most of the time the nut sticks out a little too far and the hole in the seat base, backrest or whatever needs to be oversize to accept the nut, then a washer and another nut to hold in place...hope i didnt confuse you..


the spiked nuts will work but you need to be almost perfect on bolt length or else iof you push in toi hard on the cushion youll get an end of a bolt up somewhere its not wanted. ;/

 

[ax1lla]

Re: screws under foam...

Thanks for the reply cedarjunki. I think I'm still missing something though. how do you get the nut on without the head of the screw turning?

This is for the open bow section that screws right into the fiberglass. so, the seat backs and sides...

 

[evol]

Re: screws under foam...

I did the backs of my cushions like this with a machine screw with the tapered head and a t-nut.. sorry its a crappy drawing, then I just put it through the top cap of the boat and use a bolt and washer on the other side.

Works fairly well, but definitely watch the length of bolts if you dont have a lot of clearance

 

[ax1lla]

Re: screws under foam...

evol - thanks for the illustration. But, wouldn't the screw head still turn when you put on the nut? Keep in mind the head of the screw will not be accessible to me because the foam and vinyl will be covering it. So, when I start screwing on the bolt, the head of the screw will just turn with it. Hope that makes sense....

 

[cedarjunki]

Re: screws under foam...

if you first secure the stove bolt to the plywood it will be tight in place for when you assemble on the boat then add the nut.

sorry its actually called a carriage bolt, ive always refered to them as stove bolts...
http://www.iboats.com/Boat-Parts-Ac...-keywords.carriage bolt--**********.033704987
they have the square section under the dead which embeds in the plywood holding itself secure. just make sure the hole is the size of the bolt and no bigger or they wont grab.

 

[wca_tim]

Re: screws under foam...

what you need are stainless t-nuts... made for the job and make it easy.

Here's a link with a picture. I tried a search and they don't sell them here. I usually have gotten them at the fastenall store, but can't find them in theoir online catalog. I checked and iboats doesn't sell them. this link should give you an idea what I'm talking about (picture...)

 

[SuperNova]

Re: screws under foam...

if you first secure the stove bolt to the plywood it will be tight in place for when you assemble on the boat then add the nut.

sorry its actually called a carriage bolt, ive always refered to them as stove bolts...
http://www.iboats.com/Boat-Parts-Ac...-keywords.carriage bolt--**********.033704987
they have the square section under the dead which embeds in the plywood holding itself secure. just make sure the hole is the size of the bolt and no bigger or they wont grab.

He's got it right there.....carriage bolts. Drill the hole in your plywood just big enought that the square part under the head can bite into the wood, but also let the bolt pull down far enough that the head "hides" under the foam. It is how it's done.

 

[cedarjunki]

Re: screws under foam...

what you need are stainless t-nuts... made for the job and make it easy.

Here's a link with a picture. I tried a search and they don't sell them here. I usually have gotten them at the fastenall store, but can't find them in theoir online catalog. I checked and iboats doesn't sell them. this link should give you an idea what I'm talking about (picture...)

maybe i havnt worked on a new* enough of a boat, but every one that ive done and seen used carriage bolts. and then wingnuts to fasten down to seat base/backrest/armrest whatever. umm... no link???

 

[wca_tim]

Re: screws under foam...

duh, sorry bout the link! these work much better than carriage bolts...

http://www.jamestowndistributors.com/userportal/show_product.do?pid=1746

you can either drill the pilot hole and install the t-nut under the foam so you put bolts in from the outside, or you can put the t-nut on the backside and run the bolt through from under the foam - it'll hold the bolt in place and make it easy to slip the panel into the holes and put nuts on the back without leaving a regular nut to stick out anywhere. pretty slock once you use them and see how well they work.

that's how the original seats and interior were put together on my 1988 model and that's how the new factory interior I ordered a couple years ago came from the factory as well...

 

[Chuck Gibson]

Re: screws under foam...

T-nuts were on my 78 Lone Star tri-hull as well. Just make sure that you get stainless steel. Some of the original ones that came on my boat were carbon and they rusted to nothing in no time. The only thing I could figure was that they had a batch of mixed up T-nuts at the factory when the boat was built.

 

[ax1lla]

Re: screws under foam...

Thanks a million for the replies everyone!

I feel dumb, but I had no experience with carriage bolts and didn't know how to properly use them. I tried it out on a scrap piece of wood today and realized it was as simple as a pilot hole and then simply tap down with a hammer.

I then screwed on the nut without a problem.

I think the spiked t-nut would work fine as well. but it would take a little more precision to get it just right.

Again, thanks for the help - this site/forum is great for newbies like me.

Corey

 

[109jb]

Re: screws under foam...

http://forums.iboats.com/showthread.php?t=347724

 

[cedarjunki]

Re: screws under foam...

http://forums.iboats.com/showthread.php?t=347724

the only problem i see using the t-nuts........over time you would have to rip off all that pretty vinyl to retighten as the wood shrinks. other than that looks better than carriage bolts.

 

[Chuck Gibson]

Re: screws under foam...

On my old boat wood shrinkage was never a problem, wood rotting was. Once the wood started rotting I had to remove the vinyl and start over anyway. I have been thinking about a way to get out of this happening in the future. Has anyone here ever tried fiberglassing the wood, not stapeling the cushens but rather using velcro so the cushens could be removed and hung out to dry? I know this would look kind of ghetto but if it would keep you from having to replace rotten wood for two or three decades...