Hello all, I plan on defoaming my 96 rn superjet this week/weekend coming up. I have ordered all the materials needed. While I’m in there I’m gonna seal everything up with some 5200 then reinforce the tray area and Install some drains, already have footholds. Anyway, I’m a little confused in refiberglassing the tray in, I plan on cutting a square out of the flat section a large one near the size of the tray, when I’m ready to fiberglass it back in do I put the old piece I cut out in place and fiberglass that piece in place or Toss that piece and just cut and fiberglass fresh cloth with epoxy resin and how many layers? I’ll be using 8.9oz s-glass from us composites. Any help is appreciated, I’ve tried searching but can’t come up with anything clear. This is my first time. Thanks in advance all!
How to refiberglass tray after defoam and refoam??
- Thread starter Afed24
- Start date
Re-use the piece you cut out for sure.Probably need some biaxiel glass that is thicker.Several builds of late show what others have done. Look up
http://www.x-h2o.com/index.php?threads/rn-superjet-colander-build.191659/
Also
http://www.x-h2o.com/index.php?threads/project-dance-floor.192934/
These are good reference's to help you decide what is best for you to do to yours!
If you use a Google search to look up tray reforming,it does better than the X search.
Good luck
http://www.x-h2o.com/index.php?threads/rn-superjet-colander-build.191659/
Also
http://www.x-h2o.com/index.php?threads/project-dance-floor.192934/
These are good reference's to help you decide what is best for you to do to yours!
If you use a Google search to look up tray reforming,it does better than the X search.
Good luck
On mine I ditched the old floor piece but my project dictated it more than anything. I went wide tray and a massive toe hold, additionally I changed the height of the surface.
If you are just re foaming the tray then cutting a square out like you said is the method I would use.
You need to decide what re-foam method you want to use.
You can use pink/blue insulation foam from homedepot/lowes to avoid water soaking two part foam. If you do that you lose some stock structure so additional layers of glass will need to be applied over the entire floor and the bottom/sides of the lower hull rear of the fire wall. Ensure to tab up the gunwales a few inches. Additionally when it comes to tabbing layers ensure you are, with each layer, tabbing over the prior layer by at lest a quarter inch so each layer has a mechanical bond to the base structure in addition to the chemical bond to the rest of the layup. Additionally this method will likely require additional supplies since building bulk will likely require a thicker base material than 9oz. I would use 17oz biax or 17oz biax with backer for the reinforcement.
Two part foam in 2lb or 4lb per cubic foot flavor. Easiest method however most possibility of getting water logged.
A combination of the two. This is the method I used. I crammed as much blue insulation in as I could then sealed the tray with my fiberglass plate I made and drilled 4 holes to pour the foam in the gaps that the blue foam could not fill. I stuck half in OD pvc in my drains and pulled them out after cure to ensure I had a channel for water to collect if I ever spring a leak.
The last two methods should be able to be tied in with the Sglass you ordered, I would use several layers at least, probably shooting for 30 or 40 oz of build up on the seams. ensure to tab over the previous layer a quarter inch or more for each layer.
Do not use great stuff foam or you will be at it again next year.
Good luck.
If you are just re foaming the tray then cutting a square out like you said is the method I would use.
You need to decide what re-foam method you want to use.
You can use pink/blue insulation foam from homedepot/lowes to avoid water soaking two part foam. If you do that you lose some stock structure so additional layers of glass will need to be applied over the entire floor and the bottom/sides of the lower hull rear of the fire wall. Ensure to tab up the gunwales a few inches. Additionally when it comes to tabbing layers ensure you are, with each layer, tabbing over the prior layer by at lest a quarter inch so each layer has a mechanical bond to the base structure in addition to the chemical bond to the rest of the layup. Additionally this method will likely require additional supplies since building bulk will likely require a thicker base material than 9oz. I would use 17oz biax or 17oz biax with backer for the reinforcement.
Two part foam in 2lb or 4lb per cubic foot flavor. Easiest method however most possibility of getting water logged.
A combination of the two. This is the method I used. I crammed as much blue insulation in as I could then sealed the tray with my fiberglass plate I made and drilled 4 holes to pour the foam in the gaps that the blue foam could not fill. I stuck half in OD pvc in my drains and pulled them out after cure to ensure I had a channel for water to collect if I ever spring a leak.
The last two methods should be able to be tied in with the Sglass you ordered, I would use several layers at least, probably shooting for 30 or 40 oz of build up on the seams. ensure to tab over the previous layer a quarter inch or more for each layer.
Do not use great stuff foam or you will be at it again next year.
Good luck.
@Sanoman & @Req thankyou both. That’s a huge help, I understand way way more now. I’ll be using a combo or the 1708 biax and the 9oz s-glass. Also going to be refoaming with the pink or blue insulation from Home Depot and probably throwing some 2 part over top to end it off to hold things in place and provide some kind of support. Also do either of you know if I don’t cut out my footholds and or gunwales will I be able to seal the bondline or do I need to cut that stuff out? Also do I need to use any different kind of sealer when I lay the new glass down, do I need to seal the first layer or 2 or if I do many layers will it be fine just using the resin on the fiberglass mat? Thanks again guys
What is your thought on reinforcing the bond line behind the tray sides? It should not leak and I think it is plenty strong stock in most cases. I think for what you are doing its likely unnecessary, If we were talking about the engine bay it would be another story. The foam provides structure and unlike the engine bay where its hollow, the entire cavity including the gunwales should have foam in them if the guy that did the footholds did it properly. That foam gives it more structure than you would think.
Here is an anecdotal example. I did a wide tray on my superjet where there is no hollow cavity with foam in the gunwale, just solid glass. The material removed could not have been more than an eighth of an inch thick but since it forms an arch and is cored material you get the strength required to withstand letting it go off a wave in the surf or off a boat wake and not crack. It is very much like a boxed frame on a vehicle is far superior to a c channel frame. Once I sliced the gunwales and only had the outer skin it would flex like a piece of balsa. I ended up going almost a half in thick to get the same strength back.
About the resin. Use 3:1 epoxy laminating resin from US composites for everything. Get the two gallon kit, it will go faster than you think and having extra is always good. You can use it to wet out all the products we are talking about as well as make glue, faring compound, and filler material with different ratios of Cabosil and 3m micro-spheres.
Good luck and PM me if you want to talk via phone, I would be happy to pass my number along.
Here is an anecdotal example. I did a wide tray on my superjet where there is no hollow cavity with foam in the gunwale, just solid glass. The material removed could not have been more than an eighth of an inch thick but since it forms an arch and is cored material you get the strength required to withstand letting it go off a wave in the surf or off a boat wake and not crack. It is very much like a boxed frame on a vehicle is far superior to a c channel frame. Once I sliced the gunwales and only had the outer skin it would flex like a piece of balsa. I ended up going almost a half in thick to get the same strength back.
About the resin. Use 3:1 epoxy laminating resin from US composites for everything. Get the two gallon kit, it will go faster than you think and having extra is always good. You can use it to wet out all the products we are talking about as well as make glue, faring compound, and filler material with different ratios of Cabosil and 3m micro-spheres.
Good luck and PM me if you want to talk via phone, I would be happy to pass my number along.
Awesome, if that’s the case I won’t be touching the gunwales or the bondline. Just gonna cut a basic square out of the tray and 5200 some things in there to make sure it’s sealed and throw down some foam and get her back in. Riding season is upon us I want to get this done ASAP! Also I just checked out your entire 25 page build thread.... all I have to say is wow. What a build and it looks amazing great job! I will definitely pm you for your number, Any info is greatly appreciated. This will be my first time glassing and doing the tray defoam and refoam. If I wanna make a checklists to make sure I have everything what would I be missing if this is what I had so far
2 gallon of resin 3:1
1708 biax 3yrds
9oz s glass 3yrds
Pink/blue foam board
3m 5200
2 part expanding foam
I would add 5qt of Cabosil and microspheres, they are handy and for any filling required. Additionally the pumps for the resin make measuring easy and spill free. I tried by weight and was losing more resin and hardener than I cared to.
A fiberglass roller is also handy. I think I got the 3" one. Not the end of the world, you can use a bondo spreader or just your gloved hands to get the excess resin and any air out, depends on the repair/surface the best tool to use.
It will all start to make sense when you start wetting this stuff out and working it. I would do a small plate on a trash bag to test your method before graduating to the repair. Also remember prep is as, or more important than the layup. It doesnt matter how awesome the layup is if it does not stick.
Make sure it is totally clean before you sand to not rub grease in, I wash with purple power, then dawn, then acetone, then I power sand paint and a tiny bit of the hull off to get good material to work with, then I take 40 grit and hand sand the area to get lots and lots of little scratches in varying directions, then I acetone again. Since we are talking about a mechanical bond and not a chemical bond you need to make it like velcro. The fingers of resin will fill these scratches and create an interlocking lattice, this is the thing connecting it to the hull, do not skimp on this step. You do not need to do this between layers when you initiate the repair, each layer will chemically bond to the previous layer as long as they are layed during the resins working time. I do my repairs in one go if I can.
It will all start to make sense when you start wetting this stuff out and working it. I would do a small plate on a trash bag to test your method before graduating to the repair. Also remember prep is as, or more important than the layup. It doesnt matter how awesome the layup is if it does not stick.
Make sure it is totally clean before you sand to not rub grease in, I wash with purple power, then dawn, then acetone, then I power sand paint and a tiny bit of the hull off to get good material to work with, then I take 40 grit and hand sand the area to get lots and lots of little scratches in varying directions, then I acetone again. Since we are talking about a mechanical bond and not a chemical bond you need to make it like velcro. The fingers of resin will fill these scratches and create an interlocking lattice, this is the thing connecting it to the hull, do not skimp on this step. You do not need to do this between layers when you initiate the repair, each layer will chemically bond to the previous layer as long as they are layed during the resins working time. I do my repairs in one go if I can.
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You get a chemical bond if you lay them one after the other. Do a layer, wet it out, get out air and make sure its got a nice bond, rinse, repeat. You are good for at least several layers, I have done five with the proper timing.
Im currently being disappointed by Game of Thrones so keep the questions coming, I have 59 minutes left of this monstrosity and the series is done.
Im currently being disappointed by Game of Thrones so keep the questions coming, I have 59 minutes left of this monstrosity and the series is done.
Just an update for anyone who may come across this wondering the same thing I did, having never done fiberglass before really I was skeptical about doing this and thought it would be very difficult, given I am mechanically inclined I was still skeptical but I wanted to do it anyway. So cutting the tray out was easy and defoaming was sort of easy just time consuming as is the whole job, more time consuming then difficult, the hardest part was laying new glass. After putting in new foam I threw the old tray back in and stitched in that piece with 4 strips around all sides of where I cut then I layed 3 sheets of 1708 biax each being at least 1/2” bigger then the previous on all sides and then 2 layers of 8.9 oz S glass 1/2” bigger on all sides then the previous and the last 2 layers I went a few inches up the gunwale for a good bond. In my honey opinion getting the bubbles to cooperate was easier on the 1708 biax then it was the s glass, the s glass took me a little more time to get to lay nice when it wanted to fold in certain corners but i was able to get it all to lay nicely and it feels solid now... like a rock. All in all this job was easier then I thought just more time consuming. I’ll post a pic of the tray right after the lay up. Also for anyone who reads this I couldn’t have done it without @Req this dude was super super helpful and extremely knowledgeable and was willing to help in any way he can. All the credit to him for having so much info to give out and help me and he will always answer ASAP
- Location
- Phoenix, AZ
Great thread, I know it's old but I'm looking to do something very similar to this soon. Just wondering how long it took you? Was this a bang it out in a weekend job or was a few month ordeal?
Thanks!
Thanks!
Would be difficult to get it all done in a weekend.You really need to plot out a plan beforehand.This first one,take your time and learn the process.And ask,if you have any questions.We are all here to help
- Location
- Phoenix, AZ
Okay cool, thanks!