Discussion in 'Boat and Accessory Building' started by Dan_Millsip, Mar 15, 2006.
Would you spray or brush on the next boat?
There's plusses and minuses to both methods of application Dave. Brushing definitely uses less LPU and gets a nice glossy finish but it's not easy to get a consistent thickness. Spraying uses a LOT more LPU (I used 3 quarts on the Coho), doesn't get as glossy a finish as brushing but the finish is MUCH more consistent and less likely to run/sag. Spraying will require wet sanding and buffing to get a glossy finish.
I think I'd opt for the spray method again next time -- I think by the time I'm done with the Coho, the finish will look nicer than it did on my double.
A few things I've learned from spraying:
- use light coats but lots of them
- a light sanding between coats makes a big difference in the smoothness
- we did NOT use a HPLV sprayer this time and this may account for the lack of a glossy finish because the edges of the spray pattern have more air than LPU, which can cause pre-mature drying of the LPU that is already applied -- when this happens, you end up with a "matt" finish due to the "dusting effect" of LPU particles.
I didn't realize that the fellow who sprayed my boat wasn't using an HVLP sprayer until we we'd nearly completed the process (I know very little about sprayers so didn't know the difference) but he definitely did a good job of spraying the LPU. Afterwards, he said that an HPLV sprayer may have reduced the matting effect because it most likely would be applied without so much air in the overspray. He was more familiar with a standard siphon feed sprayer so that's what he used (I think he was concerned that the HPLV sprayer would utilize more product).
Next time around, I'll most likely buy an HVLP gun and try spraying it myself.
Dan wrote: Next time around, I'll most likely buy an HVLP gun and try spraying it myself.
Yeah. I bet you will prefer the results. I thought HVLP sprayers produced much less overspray ... which may consume less paint that the system your buddy used.
That is a sharp looking boat Dan.
I like the idea about using the ketsup bottles and syringe to measure small amounts of epoxy and resin.
What size syringe did you use to extract the epoxy/resin from the respectives bottles? Are they the same size/type as what came with the Pygmy kit?
Thanks for sharing your build...I have learned a lot from this site.
TP, the syringes I used were not from the Pygmy kit -- they were 10ml syringes used for irrigating wounds, etc. The plastic "needle" part of the syringe has two holes that exit in opposing directions -- I had to cut the ends off before using.
The syringes that I used can be picked up at most pharmaceutical outlets.
btw: I'm about half way through wet sanding the final finish. I plan to wet sand to 1200 and then buff the finish to a gloss.
Today was a good day. I finished wet sanding the deck to 1200 grit this morning and had about a half hour to do a bit of buffing. This is the section from the front cockpit to the bow (there's still a bit of touch up to do on this area yet):
Dan...that shot is incredible!!!
I was in to the WCK shop around New Years - you weren't there - and the owner (I think) took me through to see some kayaks. There was yours, sitting so pretty. I was impressed then, but now I can't believe the finish you're getting on it. Inspiring work for all of us!
I hope we're going to see it at Portland Island.
wow really impressive dan!!!!!! 8O
if i would own a pretty boat like yours--i think i would have to hang it up in the livingroom
Coho Q & A
That's an absolutely beautiful finish! What grades of paper did you use to get down to 1200? What compound are you using to buff?
OldPro, I used 400, 600, 800, and 1200 grit sandpaper -- with lots of water. For polishing, I'm using Mequiar's Machine Glaze -- doing 3 - 4 applications.
Ian Mc, the boat will be at Portland Island -- my daughter will be paddling it.
OldPro, I wasn't quite correct about the buffing compound (checked the label today). What I'm using is Meguiar's Mirror Glaze Diamond Cut 2.0 (level 85) with a Meguiar's wool pad. Once I complete with the level 85, I'll do one more round on the deck using the same product, only finer (level 15).
Managed to get a couple of hours in the shop today:
I still need to hand buff the tight areas around the cockpit and do the hatches. Other than that, the only thing left to do on the deck is buff it once more with a finer compound.
Then I'll buff the hull...
omg! that is just amazing :shock:
Here's another angle:
I'm in awe; that's just gorgeous!
It does look amazing Dan, but I will withhold final approval until I see the decklines and hardware you have chosen...
OK, that does it. I'm refinishing my Tern already. :shock:
that looks awesome Dan. Any estimates on how much time you've spent on the sanding and buffing? For example, approximately how long does it take to complete the deck for 1 round of wet sanding or buffing?
Are you doing the fine sanding and buffing on the deck only? I guess the hull would get marked up very quickly.
BTW, send me a PM if you have an interest in trying out an HVLP sprayer.
It took me about 3 hours to sand the entire LPU coated boat with 400 grit. Another hour and a half for 600, and about an hour total for 800 and 1200 grits.
I spent about 2 1/2 hours buffing the deck so far and I still have to hand buff around the cockpit -- I suspect that I'll spend at least an hour or more there. I'll then buff only the deck with a finer compound -- I'm guessing that I'll be an hour or so on that. Hatch lids will take about an hour.
I'd estimate total time on the finish will be 10-12 hours.
I didn't sand as thoroughly on the hull as I did the deck but I did sand to 1200 grit. Mainly I was concerned with the two topmost hull panels. I do expect the hull to get scratched up pretty quick -- especially the keel panels.
I won't be paddling this boat up onto beaches but I don't intend to baby it either. The darker colour of the Sapele plywood will definitely show scratches a lot more than the lighter Okoume and I expect it won't be long before the hull is going to have a lot of scratches on it -- that's just the way it will be. And that's OK with me.
I enjoy doing the finishing work on these boats and get a lot of satisfaction from the entire process of building kayaks. But I also like paddling them and know that because of this, the finish will take a beating. But in the end, they are boats and will be treated accordingly regardless of how shiny they are to begin with. If I had wanted a coffee table, I would have built a coffee table.
But for a while before it gets scratches on it, it's going to be one very shiny kayak.
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