Gelcoat/x dimension

[CDMA]

Ok well I just finished spraying the entire inside of the hull with Gelcoat. It looks GREAT. Took three gallons but I think I got close to the 20 mills of thickness that I wanted. The Vacuum bagging in the engine compartment really made a huge difference. You can very easily tell where it ended. So all and all I am very happpy with it. I will try to get pictures ( as well as the 22) soon but the scanner I use died so I am a little out of luck.

Ok for you alpha guys I need some help with the x dimension. I think I am resigned to going up the full 2.5 inches regardless of hatch clearance issues. I can easily solve carb clearance issues with the awsome OEM donzi scoop I got from Forrest but I am a little worried about the center rise manifolds. So this this is mainly directed to Gene/Scott and Forrest... I need some kind of measurements to figure out the vertical distance I want from the keel. I want to make sure I get this in the right spot before I carve up my new transom. I was thinking the easiest way would be to get a measurement of Gene's with the deep v bottom like mine and add whatever I wanted...anyboady else got any ideas? Also please feel free to throw out any opinions regarding this please please please say it now before I cut the hole.

Chris

[GeneD]

Chris,
This would be a tough one for me being in Philly right now.
I did do this once before, check archives for "X-Dimension" thread and you should find my measurements.
Can't wait to see this bad boy.

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GeneD
007
Melbourne, Florida

[Scott Pearson]

Chris,
I wnt up an inch and a half on my X-dem. I have a 1968 Barrel back. I can take some measurements if you like. Just let me know.


(NJ)Scott

[CDMA]

Scott,

I would like to talk to you about a few boat related things. Could you e mail me your phone #?

Chris

[Jamesbon]

Chris,
Do you have to use a special gun to spray gelcoat?

[GeneD]

Normally I use a roller and a brush for the nooks and crannies!

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GeneD
007
Melbourne, Florida

[CDMA]

I know there are specail gelcoat guns but I didn't have one so I improvised. Not wanting to use my good gun I went to Home depot and bought a $36 home spray gun with a big orifice meant to spray heave latex paints and so forth. I thinned the gelcoat with 10 -15 % by volume of acetone and it worked great. I did spray half a can of acetone through the gun between every other load so the tip wouldn't gum up. I too have brushed and rolled gelcoat. This was far superior. Much more even coverage, thicker, faster and just better. I highly reccommend it.

Chris

[GeneD]

I thought the thinner for gel-coat was styrene?
I too tied the acetone trick and it didn't seem to work for me, probably too little of a tip on the gun...

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GeneD
007
Melbourne, Florida

[Len]

Gene D . The thinner for gel-coat IS styrene if you wish to keep its' properties relativley in tact. Doing an engine compartment or any other inner hull painting, the changes in the make up of the coating will go unnoticed. There are a couple of ways to spray gel-coat. One way is with an extrememly expensive post cat set-up where hardners meet the product as they exit the tip, and the other, that works great is a "cup gun". I've seen these for as little as $250. The "cup" is on top of the "conventional looking gun" with gravity to assist in the delivery of the product to the orfice. They work great. Keep in mind you only have a little time to work this stuff and you can't leave your gun on the ground for 30 minutes or so and look at what a great job you just did. It will then be frozen-up. Ideally, all you will ever do is mix the gelcoat, add catalyst and mix it in and then squirt the product as supplied by the chemical manufacturer. There is a balance between the components and its viscosity and adding styrene to it will make it more workable but change it's design make-up considerably. Also, overmixing causes problems and if done in this manner it has to be allowed to "sit" for 30 minutes or so. (no-hardner). These are all problems that rear their heads normally in mold/hull lay-ups as opposed to a free application such as an engine compartment. Here is an interesting site regarding gel-coat and laminate lay-ups. (a bit of insight for Blister-boy)Chapter 1 is best.
[URL=http://www.osmosisinfo.com/what_causes.html]

[This message has been edited by Len (edited 03-18-2001).]

[CDMA]

The gelcoat can said either would work. I had the acetone so I gave it a shot. Worked great.

Chris

[CDMA]

Ok folks

Mix part A with part B
stir
add thiner
stir
put in cheap ass gun
pull trigger
stand back and watch
smile

[CDMA]

Oh and the back of my "clear cote pure white can" speciafically says that either Styrene or acetone are both approved thinners for spraying. If it is good enough for the manufacturer it is good enough for me.

CDMA

[This message has been edited by CDMA (edited 03-18-2001).]

[This message has been edited by CDMA (edited 03-18-2001).]

[Jamesbon]

Cool! Thanks fellas. Would you recommend using gelcoat as opposed to Awlgrip or Imron for the outside of my boat?

[Christian]

hello all,
we have used both methods of thinning. But i like chris's method the most. smells less and get a better result if done right. for touch up jobs on bigger boats and the r/cs we go about it that way. we haven't had to touch up the 18 yet. (knock on wood). the guns with the cup on top are gravity feed guns they are nice to use!