I have only managed to get about half the bad bog stripped off so far but I have only put in about 6 hours so at that rate it should only take about 12hours rather than my original estimate of 20. The more I do the faster I get but caution is still needed as the risk is ever present that I will cut the surface glass. I have cut into the glass here and there but whenever I feel the chisel cutting into the glass stop and come from a different angle to minimize the damage. I am sure that I have not damaged the glass at all. In the first pic you can see that the bog on the left (stern) is the good bog applied before the pump broke. It is a lighter color than the bad bog and it has set fine and hard and will need to be sanded. The chisel wont remove that. The soft bog is darker but I didn’t notice the change in color or didn’t understand the significance if I did when I was applying it. The second pic shows how easily the chisel will take the bog off although it doesn’t show how tiring the work is as you do have to push hard, there is a lot of resistance. Sometimes I worked along the hull in longer strips sometimes in shorter strips up and down, other times I went across hull along the glass grain.
I found that no real pattern in what was the best way to strip the soft bog off, sometimes it was easier going with the grain of the glass other times it was easier against or across the grain. When I say easier I mean that the chisel would not catch on the glass or dig into the resin too deep. The trick I think is to get the chisel as parallel to the hull as possible which means I scraped the skin off my knuckles but if I lifted my hand away from the hull increasing the angle of the chisel to the hull the chisel went deeper and caught the glass. I will be wearing gloves over the weekend when I strip the rest of the hull.
It is almost impossible to remove all the bog with the chisel but the idea is to get the bulk of it off and use the sander to remove the rest. You can see how much is still left on the hull before sanding an how smooth it comes up afterwards. In fact it may come up very well because the bog left is creating a feathering from the flat hull to the higher edge of the glass smoothing it out meaning I am probably going to need less bog overall to achieve the all over smoothness that I was aiming for in the first place.
So to recap, I had about 15% of the boat properly bogged so I had to remove 85% and I am about 1/2 done removing the bad bog or about 40% of the boat is stripped. I think I will be able to strip the rest of the boat this weekend. I will then sand it all ready to re apply resin and bog.