fiberglass warped on transom

twkjr 1250

Petty Officer 2nd Class
Joined
Mar 6, 2009
Messages
177
I just removed wood from transom due to it being soft. I noticed that where the stern drive was bolted to the transom plate ,starboard middle two screw holes glass was warped . the warpness covers about a 2x6 inch area . how can this be fixed ,before or during new wood transom replacement. Have one more thing to ask while on transoms aponn removal of old transom i noticed lines verticaly and horizontaly across transom . I thought it may have been peiced but saw it was one peice of ply purposely scored . Anybody have any idea why they did this . I could only think better lamination to the fiberglass .
 

Attachments

  • dolphin restore part three  transom  and stringers 025.jpg
    dolphin restore part three transom and stringers 025.jpg
    135.2 KB · Views: 1
  • dolphin restore part three  transom  and stringers 022.jpg
    dolphin restore part three transom and stringers 022.jpg
    144.1 KB · Views: 1
  • dolphin restore part three  transom  and stringers 023.jpg
    dolphin restore part three transom and stringers 023.jpg
    149.1 KB · Views: 1
  • dolphin restore part three  transom  and stringers 017.jpg
    dolphin restore part three transom and stringers 017.jpg
    152.6 KB · Views: 1

twkjr 1250

Petty Officer 2nd Class
Joined
Mar 6, 2009
Messages
177
Re: fiberglass warped on transom "update"

Re: fiberglass warped on transom "update"

33 hits and no bites . ok maybe its the pics . well since last post grinded the transom down to the glass . everything went pretty good , then the warp said hello what about me. I told the warped spot to wait another day ,so i can get some help from somebody nice on iboats . so don't let me let the warp down. hope these pics are better thanks guys warp in transom will appreciate it oh yea what can i do about the spider crack in the last two pics
 

Attachments

  • dolphin restore part three  transom  and stringers 028.jpg
    dolphin restore part three transom and stringers 028.jpg
    139 KB · Views: 1
  • dolphin restore part three  transom  and stringers 030.jpg
    dolphin restore part three transom and stringers 030.jpg
    149.5 KB · Views: 1
  • dolphin restore part three  transom  and stringers 031.jpg
    dolphin restore part three transom and stringers 031.jpg
    136.2 KB · Views: 0
  • dolphin restore part three  transom  and stringers 032.jpg
    dolphin restore part three transom and stringers 032.jpg
    150.7 KB · Views: 0

Woodonglass

Supreme Mariner
Joined
Dec 29, 2009
Messages
25,929
Re: fiberglass warped on transom

Well it must be my 60 yr old eyes but I am NOT seeing any warp. I do see some Cracking but Warping"???? Not!!! Cracking can be fixed with glass and resin. what does the OUTSIDE of the Transom look like? Take some Vertical pics. Maybe that will better show the warping.

I'm just sayin...:D
 

ondarvr

Supreme Mariner
Joined
Apr 6, 2005
Messages
11,527
Re: fiberglass warped on transom

Until you put the level on there I don't think anybody could see it in the pics.

You can put a board on the outside in the same position as the level and then screw the transom skin to it, this will pull it flat while you glass the inside. It may not be perfect after that, but you can do some work on the outside to finish it off.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,082
Re: fiberglass warped on transom "update"

Re: fiberglass warped on transom "update"

Ayuh,... If the Thickness of the glass is consistent, the Final product will be Flat, 'n True....

You're going to gain strength, 'n trueness from the couple inches of plywood you're gonna glue to that...

Peanutbutter the holes, sand smooth, then glue, 'n clamp the wood to it,... It'll flatten out...
 

twkjr 1250

Petty Officer 2nd Class
Joined
Mar 6, 2009
Messages
177
Re: fiberglass warped on transom

thanks guys now i can proceed with confidance.
 

wishboneZ51

Petty Officer 2nd Class
Joined
Jul 11, 2010
Messages
135
Re: fiberglass warped on transom

Yes, I definately see warping in that starboard side. I don't know if it came from the factory stacking 2X6's horizontal like that. I can see how you get warping from using that method. Another idea you can use is the sandwich method where you take hardwood in the center and sandwich it with ply on the outside.

I would take another aproach to your problem if I may. I would most definately build my transom outside of the boat, and cover the top, front and back with 1708 glass with one to two layers. Once that was complete I would prep the back of the transom which is your warped section and prep it for a layer of 1708 glass. But when you do this you want to be adding the glass to the transom at the same time as installing your newly built transom to the warped section. The last and final stage would be to distribute the weight of clamping along the entire stern and transom area. This will be your critical placement for correcting the warping. Conform the warp to the new transom not the other way around. Once you complete this faze adding another layer of 1708 to extend along the entire transom, sides and bottom of the hull atleast 8-10 inches would help lock everything in place. Just my 2 cents which aint worth much.
 

Yacht Dr.

Vice Admiral
Joined
Feb 26, 2005
Messages
5,581
Re: fiberglass warped on transom

Hello 1250..

More then likely that trans has Allready been replaced..

There are too many bullet holes in that pic that would be from the factory ( though I dont know what kind of boat or year ).

Just seems like reps have allready taken place.

As for ply score .. most likely that the PO didnt know how to apply 1 full trans @ 2x3/4" into the thing without more hassle.. so ..

Or It could be that the PO thought that cutting the wood and glassing would reduce the amount of damage done from water intrution from the drives/through-hulls on the transom ( keeping the damage localized basically ) . who knows for sure..

Now as far as "clamping" .. there are transom clamps you may be able to rent..or build your own.. they are called Transom clamps..

Not clamps you buy at HD :) .. unless your going to weld ..

Again.. there are threads on how to bond ( Inside lam or outside lam ) transoms here on Iboats ..

Good luck m8..

YD.
 

twkjr 1250

Petty Officer 2nd Class
Joined
Mar 6, 2009
Messages
177
Re: fiberglass warped on transom

did a dry run on clamping that section of transom that was warped , however it went back to the same shape and took alot of pressure to get it clamped straight . wish bone z51 gave me a idea to re glass transom after grinding out the warped part. not exactly what he said but inspired me to put me on the right track. this is a fight i will enjoy quiting . grinder wins clamps lose. thanks wishbone
 

Mark42

Fleet Admiral
Joined
Oct 8, 2003
Messages
9,334
Re: fiberglass warped on transom

I would just run screws through the glass and into the wood to pull the warp flat until the resin cures. Then remove the screws and fill with thickened resin. No clamps needed.
 

twkjr 1250

Petty Officer 2nd Class
Joined
Mar 6, 2009
Messages
177
Re: fiberglass warped on transom

i have read alot of post about screwing through the transom dont mind that , how ever if by chance it dosn't hold i will be forced to seperate new transom and grind and do it again .my big fear is a proper seal for transom plate. by the way had a iboat member mention about no wy to completely seal transom . he said no matter what you always have to drill holes through it . i have a idea i will be testing out that may be improving or completely resolve the problem. i will post it when every thing is on paper and on my transom in working order . i think it will be a major break through for us.
 

wishboneZ51

Petty Officer 2nd Class
Joined
Jul 11, 2010
Messages
135
Re: fiberglass warped on transom

did a dry run on clamping that section of transom that was warped , however it went back to the same shape and took alot of pressure to get it clamped straight . wish bone z51 gave me a idea to re glass transom after grinding out the warped part. not exactly what he said but inspired me to put me on the right track. this is a fight i will enjoy quiting . grinder wins clamps lose. thanks wishbone

Nope you have it right! Grind all of the junk out on the inside of the hull. When you have your transom built and with the first glass of 1708 covering the entire transom except the bottom you will have a strong base to work with for two reasons. First being the transom has already been wet coated and soaked with poly resin which is half the problem when wanting to get a good seal without air pockets or dry spots from a lack of resin in an area due to soaking in the wood. The second is a strong gripping surface for the next layer of glass from the back of the transom of the boat to the new transom backing board of your wood substrate and glass combo. Just make sure you scuff up the back of your newly built transom before matting it to the back of your warped stern. One other point is when you use clamps which I would highly take Yacht Dr. advice and rent some proffesional clamps this way you only do this once and not waist time effort and coin in the process of not getting it clamped correctly before your resin kicks and causes a serious disaster and mess on your hands.
 

ondarvr

Supreme Mariner
Joined
Apr 6, 2005
Messages
11,527
Re: fiberglass warped on transom

Clamps will sort of work if you get good ones, but I've done hundreds of straightening jobs just like this and I just use wood backing (as many as needed) and screws, its fast, simple and cheap. Stand a 2X8 on edge, or whatever size piece of wood is needed for it hold the transom straight and drill right through the transom skin and screw into the wood. Leave the wood on the outside of the transom until you've glassed the plywood core in place.

The other way is to make and glass the plywood for the transom before putting it in place, use glass or some kind of glue to bond it to transom skin. When its in place you can use clamps to apply pressure, but this usually doesn't completely remove the warp, so use screws going through the skin and into the plywood core, they can easily be removed when everything is hard.
 

twkjr 1250

Petty Officer 2nd Class
Joined
Mar 6, 2009
Messages
177
Re: fiberglass warped on transom

getting ready to encase transom with glass, one problem, i might have to much of a space on staboard side of transom and side . every where else looks good at least to me. posted some pics. space is about 3/4" maybe 7/8 " .this is mostly at top half of transom. how do i seal the edge of my drive cut outs ,assuming doing the cutting out after transom is installed.
 

Attachments

  • dolphin restore part three  transom  and stringers 046.jpg
    dolphin restore part three transom and stringers 046.jpg
    150.1 KB · Views: 0
  • dolphin restore part three  transom  and stringers 044.jpg
    dolphin restore part three transom and stringers 044.jpg
    146.3 KB · Views: 0
  • dolphin restore part three  transom  and stringers 045.jpg
    dolphin restore part three transom and stringers 045.jpg
    147.9 KB · Views: 0
  • dolphin restore part three  transom  and stringers 049.jpg
    dolphin restore part three transom and stringers 049.jpg
    140.5 KB · Views: 0
Last edited:
Top