RickK's 170 rebuild

[RickK]

The instructions for the gun said to spray a light coat and wait 2 mins and then start laying heavier coats with a 5 min delay between each.  Sound about right?
Having the console hanging will make this so much easier than trying to rassle it around or having to do the inside one day and the outside another  8)

[CLM65]

Looking forward to the finished console, Rick!  I'm also looking forward to learning more about spraying gel.

I apologize for not adding any updates on my rebuild.  I've been chipping away at it, but not too much visible progress.  Between the heat and all the rain we've had, well, you know....  I'll try to add an update to my thread later this week.  In the meantime, it's good to see you and Steve making progress.

[kaptainkoz]

4.8... mine came with a 6! No matter what by nature of the beast it will drip when you point it down. I cant dispute the instructions but I have a hard time with 2 minutes. I think what they mean is almost like a wetting coat to get the bond going, then a thicker coat 5 mins in. I would still consider many thinner coats than one thick coat. Personally I wouldnt go more than 2 inital passes. The gel is still "wet" and not kicked off so I think you would just be drowning the piece and asking for really really fun gel coat runs if you keep shooting coat after coat. I would think you would want the prior layer to kick and take a semi firm shape before you shoot again. I shot the first few molds a coat a day just to let the prior layer take hold except for the last doors which I shot an hour apart. I did experience some gel coat lift on those  last doors but that was a mold. I dont think it would be an issue with a top coat like on your piece. Problem/point is with layers is the different kick times of each layer. Obviously if you shoot multi layers a few mins apart they are kicking mostly at the same time. Shooting every hour is spacing that out and that may be where I got into slight trouble with the molds in trying to keep them flat as they heated and set at different paces one on top of the other. A day apart... well now that layer is set and isnt going to move for anything leaving a good base for the next layer. Im a bit under experienced and out of my league but thats my gel coat observations so far through my own trial and error.

As for quantity... I think 2 quarts could do it but it doesnt leave you much room for error. Im glad you can stretch the 1st quart with the additive as 3 quarts should definitely do it. Its not like you can mix it up and pour back what you dont use. There is waste involved because is hard to gauge exactly how much you need. I cant judge too well as I am pouring out of a 5 gallon as using what I need mindlessly. As for the waxed, basically that is your very last coat. Think of sealing the project with wax. I bought a quart of wax additive this way I can buy unwaxed gel coat in quantitiy and wax it up when I need it. I bought a 5 gallon pail of it which basically is the same price as less than 4 gallons. Quart by quart is the most expensive way to go usually. Im actually glad to hear you have the 4.8. I think the 6 tip is a bit aggressive and drops alot of gel. Ive been thinking of getting a 5. Better to spray a little less for a little longer per pass then to drown it.

As for shooting layers and fixing as you go... thats perfect and one of the benefits of gel. Shoot it, let it set, sand out what you dont like, fill what you have to then shoot again. You can mix some gel with cabosil or west systems 407 to make a putty to fill in anything really out of whack. The more coats you shoot the more meat you have to sand and fair to an amazing finished piece. Its kind of why I thought to go a little thicker on the gel in my molds so I can sand away and make it look good. Again, not what a pro would say but I have to leave room for error as a novice. As my game improves im sure my technique will stream line. until then, no one will know or care what I did to make the piece look the way it does. Be careful with those ignition indents you have over the storage compartment. You are going to pass them with the gun too many times and drown them because you will find it hard to cover that small and deep of a crevice. I see that they may be pre coated which will help not make a mess there. Tell yourself now that you will get it all later on the next coat and keep the gun moving. How are you going to shoot the door? I would think you have to hang it open somehow in order to shoot the inside. If you shoot it closed, that gap is kind of small and I fear you may bridge the gel coat from the frame to the door. Other than that the piece should shoot real easy. The best part it thats its gel coat... you screw it up, you sand off the boo boo and shoot it again. No harm done and no one will know the difference. You cant do that with paint as easily

[kaptainkoz]

A little after thought on filler. I love west systems 404. It is white so when mixed with gel you can basically fill holes and scratches, let set, sand and polish and done. But... it is a tough fiber and is hard to sand. They make 407 which is alot more easier to sand and is non structural, BUT it is reddish in color and will not work as a one step filler. Shame on me but ive never used anything else. Im sure there is a light weight, non structural filler for gel coat that is white and works great. Maybe its cabosil? Dont know. All I know is 404 works but i bet there is something lighter and easier out there.

[RickK]

The tip is a #6 and on the instruction sheet it had (4.8mm) beside the #6.
The white battery switch holes will be taped off, I made those out of epoxy so I painted the insides of them with epoxy paint.  I'll gel over the part of them inside the console to see if it sticks.

What I planned was to use the waxed first and spray half the qt inside and half outside.  After it hardens I will wipe the gel down with acetone to remove the wax and then do any repairs.  I think I have the majority of any flaws already taken care of but we'll see. The final coats will be the gel with the additive - I think it is private labelled Duratec.

[kaptainkoz]

I would use the waxed last. The wax smears and doesn't simply dissolve with acetone. I fear that there will always be wax residue unless you sand it off. Think of the small dimples in some of the fiberglass overlays and what it would take to get the wax out of there. I was never comfortable of a strong bond working on a waxed surface unless I sanded down to raw gel, and even then I envisioned smeared wax dragging in my sandpaper to some extent.  The unwaxed sets firm enough to sand in a day or two. If it doesn't, get PVA and spray or brush it on as a barrier for the final kick. PVA washes off completely with water. When I made repairs to my cast pieces I would coat the newly kicked repair gel coat sections in PVA. I'd brush a layer or two on and that was enough.
Gel coat won't stick to epoxy so mask that carefully.

[RickK]

Last weekend I did shoot the console with 2 qts of gelcoat. The dump gun was a little tricky to use and especially to remember to end with it pointing to the sky so it didn't drip/run out.  Forgot a couple times and ended up with some dribbles here and there.  That gun is aptly named - it can definitely "dump" some gelcoat quickly     I got a good coat on the console however my prep before this was not so great so it showed every imperfection and cloth print on the console and seat lid.







So then I started sanding the gelcoat down to a smooth condition and then filled all the imperfections with some bondo - took the remainder of last weekend and all of this weekend to get it really ready for the last coat with additive in it.








Next weekend I will build some sort of spray booth under the tree so I can keep the breeze down, it was pretty breezy here all weekend -  plus the darn love bugs are here now too.  :(

[gran398]

That looks good Rick. Did you try the cheap spray paint method for highs and lows?

[RickK]

Thanks.
Nope, the console is small enough that you can feel and see what is going on.  I'll do that on the bottom though.

[CLM65]

They say that with paint, 90% of the effort is in the prep.  With gel, 90% of the effort is after it is coated.  Looks like you're getting your 90% after, and then some.  Good luck and keep up the good work

[RickK]

Hope the last coat goes nice and smooth with the duratec additive.  Bought another HVLP gun with 2.5mm tip as it is recommended so it should be a piece of cake, lay out/down nice and flat and self sands and buffs   .

[kaptainkoz]

Disassemble and reassemble the hvlp a few times so you are familiar with it. You will have to get it apart before the gel sets. You can buy some time by shooting acetone but it will need a full disassembly when your done. They shoot great but it's a pain to maintain and clean.

[RickK]

Well.... I got some more progress made and then some progress removed  
I built a quick red-neck spray booth in the front yard around my work area





I added a slight amount of blue pigment to the gelcoat and then read the instructions for the duratec for the 5th time. It says you should mix 2% hardener and my gut was telling me "that it too hot for here in my neighborhood" and I compromised at 1.5%.  As I said a few posts back, the instructions also say to fog the first coat (2 mils), which I did, wait 2 mins and then start laying it on a little heavier, which I also did.




Then disaster struck - the little bit of gel I had left in the gun kicked  :cry:   And I hadn't taken Steve's advice to heart and had only practiced pulling the needle and flushing acetone through it.
Well doing that did not clean the gun so I had to learn how to take it apart while under pressure to beat the gelcoat super hardening inside the $50 gun.
A friend stopped by about that time and said the same thing happened to his boss and he said I'll show you how to take it apart and we did.  And I scraped all the gelcoat out of the gun and it was now working perfectly again  
Unfortunately I had run out time and materials so it would have to wait 'til this weekend.

It was really windy yesterday (and today too in spurts) so yesterday I started on the cabinets for the back corners of the liner where they meet the transom and where the cables and such will come out from under the sole.  I made one for both sides.  I need to find a smallish premade plastic door, like the one I have on the Explorer, so I can open the cabinet to reach in and pull all the cables out.  And then before I install it I'll cut a 3" hole in it and figure out how to split the door across horizontally to be able to seal up the access hole for the all the cabling when it exits the cabinet.  I'll use one of the rubber boot things that you usually see used in this application.


Today I got up and re-erected the spray booth and right after that the wind picked up.  Inside the booth it was nice though.  I hung the console and set the seat up and then went to mix the gelcoat and additive.  This time I used 1% and I fogged, and then got another coat on both and then one more on the console before the gun ran out of materials (and it didn't kick in the gun   )  Just to be safe I went into the shop, disassembled the gun and cleaned it all out (nothing was in it) and was done and reassembled within 5 mins.
I went back out to the booth to take a peek before I mixed my next quart of materials.

Dog gone love bugs had invaded the booth  :x
As you can see the material laid out nicely and has some shine - just has some winged adornments in some areas now.




More of the winged nosey visitors






So that ended the day - was going to be all done with spraying, now I have one more day.  I need to hit the whole console and seat with 400 now and hopefully next weekend I can spray it before the bugs come out, which seems to be around 11A.

[CLM65]

Good job, Rick.  When I saw your makeshift paint booth, my immediate thought was love bugs.  I imagine it would have been worse if you didn't have it.

[RickK]

Thanks Craig.  I'm thinking that I can put a shop fan inside the booth and after spraying, turn it on and aim it at the entry area.  Hopefully that will help.
I'm thinking I only have about 5-7mm on it now, so I need a few more coats.
I'm wondering if they are attracted to the smell of Styrene?