Saved from the Junk Pile!
Part III: Transom Removal & Grinding the Hull
These articles are written as the work
is completed. After removing the
deck, stringers, core, and transom, this
hull has become very flimsy. The
need for some serious structural support has
become extremely evident! The first step of this whole project prior to removing
anything from the hull, should have been to construct a jig that would support
the hull sufficiently to ensure its original shape.
Fortunately my brother has a viper.
Making a jig now is not a problem, but it would be for anyone who doesn't
have that option!!
With the grinding complete,
I have become increasingly concerned about the damaged area of the hull.
So I have opted to cut the repair out and start over.
While my brothers viper is upside down (for the jig) I will be casting a
mold for this section. Ron Pratt's
“Baby Virages” gives a good
description of the mold process, for anyone interested in making a mold to
perform repairs. (See topic archives below).
While constructing the mold for the
bottom section to be removed, I
kept staring at the big hook in the pad of my brothers viper.
With no experience on what works on pad modifications,
I decided to call someone who would.
Ron Baker and Garret Armstrong of Baker Marine were both extremely
helpful! (Thanks FELLA's!) This is
my interpretation of what was discussed. 6’
forward from the back of the pad needs to be as flat and straight as possible. This includes filling in the concave pad and removing the
tremendous hook, and making sure all edges are sharp and true. (I removed the
hook in my brothers hull using gorilla hair, two layers of glass, and then re
gelled those areas.)
This jig has three functions.
1) to support the hull and keep it in the correct form. 2) to hold the
mold in place. (for the side repair) 3) it holds a mold I made for a new pad,
Rather than fill the hook I have opted for a new one!!
Plus a ¼ inch in pad height. (Note:
this part is just an experiment). With
the mold complete, I started on the
template for the jig. I laid three pieces of 2x6 scrap across the bottom and
screwed them together.
Using pieces of cardboard I worked a strake at a time to get a perfect fit. Then stapled the cardboard to the 2x6 and moved on to the next section. Once the template was complete I traced it out on a ½ “ sheet of plywood. I made a template for the front and the back of the hull , cross braced it all together and anchored the two molds in place. The jig was then lifted off that hull and transported back to my house, where the project viper fit into it perfectly. The last picture on the right shows some channel iron that was added to the 2 x 4's to help reinforce them. This ensured that they would not bow or warp.
OK ... Back to the prep. To remove the transom plywood I cut it into three sections. Working layers at a time, the plywood was peeled back using my trusty pry bar. Taking great care not to fracture the fiberglass or create additional stress cracks in the outer gel coat while prying the wood from its skin. Removing the plywood took about an hour using this method. The picture with the ruler shows the thickness of the transom being 1-1/2" (excluding the outer layers of glass).
Prior to grinding, I try to remove as much extra material as possible. Using the pry bar, any loose glass is peeled away a layer at a time.
The grinding arsenal is as follows: a fresh air system, full tyvek suit, gloves, hood, ear protection and a full face shield, a gear drive angle grinder with 24 grit pads, (10) and a mini angle grinder. Grinding is a dirty, nasty job, take a lot of care in protecting yourself in the process. Trust me, you’ll be sorry if you don’t! Working in 2 hour intervals I was finished in about 4 days. While grinding, keep the surface as even as possible. I tried to take the same amount of material away in all areas, without digging in.
Prior to placing the hull in the jig,
I cut out the old repair area and prepped it for the patch. The next article will cover the patch, the new transom,
and some final preparations before the recore (still debating what to do
with the pad). Stay tuned!!
If you have any questions, please contact Chris at Boatmender@aol.com