Mini OB Boat conversion to Mini Jet Boat

Cool project. Now that you've started the shaping, it looks like the fairing should work just fine.

 

Thanks Lurvio!

 

So we filled and shaped some more.

You can see in the last image I posted that the left strake in the photo was not quite as built up as the right. We laid more material on that strake and got it closer. We also laid a coat of filler to better blend the pad.




Below you can see we need to add more filler around the front edges of the right strake to make it slightly longer and to fill the lows in that area. Also you can see some straight gouges from sanding on the inner edge of the left strake in the photos below. This is due to concentrating specifically on shaping the strakes.






We will fill those lows with the next layer of filler. It's a gradual process of adding and removing until both are even. It's getting very close though!

This is the most important part of the build so far though. Getting this accurate is essential to the performance of the boat! It may not look like good progress but there has been hours in shaping each layer. There's no easy way to measure along the way. It's a matter of doing everything by eye, paying close attention as we go, and doing things a little at a time.

As always, thanks for following and for all of your input, ideas, and comments along the way!

 

Another thing to point out is that when you are blending/building areas or voids, it is VERY important to not be sanding material off that does not need to be removed. The great thing about the AFS (Adjustable Flexible Sander) is that if used properly (applying pressure to both sides of the sander...not in the middle) it will bridge the working area and only remove highs. A lot of peoples instinct would be to put pressure in the middle because they aren't hitting the areas they are trying to blend...just to get it smooth. The fact is, if you aren't hitting those areas, they need to be built up to create a gradual transition.

 

Over the past couple of days we have done a lot of sanding, a little final shaping, and some filling. We started by laying another thin coat of the microsphere/resin filler mixture with a milkshake consistency. This filled pretty much all of the remaining low spots, then we blocked it out with the 21" AFS.

We didn't get any before photos, but these show the progress after about an hour of sanding. You can see the pad flows a lot nicer from the boat to the jetski pad. Only a few small low spots remained that look larger than they are due to the direct lighting.



We filled the remaining low spots and while we were at it we laid a layer of the same filler with more of a peanut butter type consistency on the pump extension out the back of the transom to smooth it out. It was a little tricky doing the top of the pump extension as it was upside down. But we were feeling risky and did it anyways



And here it is after a little sanding with the 9" AFS. It's pretty close! We'll probably do a final layer once we flip her over.



The shape of the hull is about 95% of the way there. We wanted to seal in all of the filler we laid as some of it is 1/2" thick or more, but at the same time we didn't want to lose all of the fairing we did. So we decided to lay two thin layers of fiberglass cloth, it lays smoother and more consistent so it will require less sanding before doing the final fairing.

We sanded the boats gelcoat down to fiberglass about 6" in front of our glass/filler work. Also sanded the yellow gelcoat off the front of the jetski section. Then we cut two large squares the same width as the boats first set of strakes, and long enough to cover all of our filler work.



Then we wet it out and made sure it was perfectly smooth. It was about 95º outside yesterday, and even with 3/4 the amount of catalyst that we usually use our work time went from 20+ minutes to about 5 minutes max. We had to work extremely quick, luckily it still laid pretty smooth!



And that's it! We will be getting started soon to finish up fairing the hull, stay tuned!

 

Might have said this before, but really admire your work. I don't envy you for all the sanding. But it's great seeing it take shape.

 

Thanks BPL. I can't imagine anyone would enjoy the amount of sanding that has gone into this project so far...but as you said it's finally taking shape, and that is really rewarding!

 

Yesterday we scuffed the glass layers, feathered them out on the edges, and then laid a milkshake mixture over the entire work area. This really leveled things out nicely, and filled the minor lows.




Sanded that down and laid a thicker filler for the more significant lows.




We sanded that out and things really look nice now. The bottom is very close to where it needs to be. My buddy Tristan will be painting the boat. I'll let him do any final prep work that needs to be done there. He's much better at it than I am.

 

Last night we notched the left stringer to make clearance for the exhaust. We then fiberglassed the area to reinforce and seal the area.




Then we glassed the notched area.








2nd Layer of 1.5oz Chop Mat






And also glassed the area where the stringers were exposed from early on in the build when we extending the recessed area where the motor sits. In the last photo you can see the right (far) stringer was not yet glassed. In this next photo it shows that stringer with 2 layers of chop mat.

 

Last night we cut the rear deck of the boat to allow the sun pad/hatch cover to extend out the back. This is to create kind of a fastback look and give a padded surface to climb out of the water on to using the swim platform.

Before:


After:


Now we have to lay some marine plywood across the void and glass it from both sides. It will give a nice hinging surface for the sun pad/hatch cover.

A good shot showing the back of the boat and how the pump shoe looks with the top of the boat on.




Photo flipped for comparison...this is where she began.

 

Removed a bunch of things last night in preparation for paint.

Steering Wheel
Steering Cable & Rack
Vents
Cleats
Windshield
Beer Holders
Nav. Light Switch

I also removed all of the "Addictor" vinyl as well as the registration numbers/stickers. I then gave it an acetone wipe down and cleaned all of the adhesive/grime where the bumper/rub rail was.

 

Awesome work! Can't wait to see it on the water.

 

Thanks Tin Horn. It's going to paint on Tuesday the 29th, and should be finished by Sunday the 3rd. I don't know yet if I'll be able to make the trip to Iowa, where it's being painted, on the 3rd though. It may June 8th or 9th before I can pick it up.

Anyways. We glassed the rear deck plywood on. This is the area that the sun pad/hatchcover will sit on and hinge on. You can see we cut the plywood to shape then taped it firmly in place from the top. This was just to hold it in place so we could tape it from the bottom.




Once we tape it from the bottom we peeled off the tape on the top so we could glass it.

We laid two layers of fiberglass cloth. It's thin but it's just to seal it. We will be reinforcing it a LOT from the underside.








Today we will be reinforcing the underside and glassing all the holes in the top of the hull from hardware, gauges, vents, etc that I am no longer using.

 

Well things NEEDED to be finished today. I leave this afternoon for a short vacation until Tuesday. On Tuesday the boat is being hauled to my buddies shop in Iowa to get painted.

We started at 7:30 this morning, by making a batch of resin with chopped strands mixed in. We used this to fill the gaps on all sides of the marine plywood we glass on last night.








Here is it with all the gaps filled.




Then we grinded the areas around all of the unused holes that we were going to fill.




Then we taped the holes on the rear deck to create wall to glass onto from the inside.




A view of that from the inside.


Then we glassed them from the inside with 3 layers of chop mat.




Then we taped all of the other holes that we had just grinded, so that we could fill them from the inside.




Here, in the bottom right you can see we filled that hole for the bow nav. light.


This pic shows how we filled the old Tach. gauge hole.


Some other random holes




All ready for Paint!!!!!!