Custom/Hybrid Hull Building: USS-ROOSKI

[Roo]

X2. I start wet at 240

thanks for the tip - will make the switch sooner then

 

[Matt_E]

I hate sanding

 

[tomski]

Sanding is the best part of the process. Imagine spraying and then sanding 5 gallons at once...

Never catalyze Duratec at under 2%; 1% isn't recommended. This could be the reason at 220 dry your paper is clogging (under catalyzed).

80 grit to start is way to coarse for me, 220 is normal. Throw that tiny block away and get a longer one! Sanding (blocking) is so important for a true plug.

Go wet after the higher grit only. And then you get to sand the mold!

 

[Roo]

Sanding is the best part of the process. Imagine spraying and then sanding 5 gallons at once...

Never catalyze Duratec at under 2%; 1% isn't recommended. This could be the reason at 220 dry your paper is clogging (under catalyzed).

80 grit to start is way to coarse for me, 220 is normal. Throw that tiny block away and get a longer one! Sanding (blocking) is so important for a true plug.

Go wet after the higher grit only. And then you get to sand the mold!

this is the last project like this i am taking on... i think.

i did it at 1% per others recommendation. didn't want the duratec geling up inside the HVLP gun. we'll try 2% on the top deck for kicks, and see if that makes a difference starting at 220. i had to much texture to go through, i would have been there for days with 220.

i like the 3m rubber blocks i am using - about perfect.

 

[Matt_E]

I'd pick up some longer flex bocks for curvier areas. I've had good success with them.

 

[shawn_NJ]

Once you get past the real bad sanding (400 wet) jump right to these (1000 & 2000) polishes and a 12' car polisher wheel. The 1000 fast cut makes quick work of any imperfections, and the 2000 it will be mirror shined ready for wax. You can have the polishing done in a night or two. You will be amazed how much faster you get the plug starts looking perfect. If you are just building the molds for yourself dont drive yourself crazy with the details. Hit the major imperfections and let the 1000 fast cut polish do the rest. Remember its a bottomdeck, thats going to get trailered and roughed up pretty quickly. You just need it smooth enough to look nice and actually release cleanly from the mold. As you know, you could spend your life trying to make it flawless....lol

It will amaze you how well this stuff works and your plug starts looking GOOD fast. Its made by Hawkeye too.

http://www.duratec1.com/dp17-18.html

 

[Dustin Mustangs]

I know I'm jumping ahead a bit here, but have you decided on a layup schedule for the hull yet???

 

[Roo]

Once you get past the real bad sanding (400 wet) jump right to these (1000 & 2000) polishes and a 12' car polisher wheel. The 1000 fast cut makes quick work of any imperfections, and the 2000 it will be mirror shined ready for wax. You can have the polishing done in a night or two. You will be amazed how much faster you get the plug starts looking perfect. If you are just building the molds for yourself dont drive yourself crazy with the details. Hit the major imperfections and let the 1000 fast cut polish do the rest. Remember its a bottomdeck, thats going to get trailered and roughed up pretty quickly. You just need it smooth enough to look nice and actually release cleanly from the mold. As you know, you could spend your life trying to make it flawless....lol

It will amaze you how well this stuff works and your plug starts looking GOOD fast. Its made by Hawkeye too.

http://www.duratec1.com/dp17-18.html

I have used Duratec before on a previous build attempt - awesome stuff for sure.

I will be taking your advice on jumping from 400 to 1000 - you are right, it is the bottom and I could be here for days if I really wanted to working out imperfections.

I plan on painting my final part, so the primer and paint should care of all the *tiny* imperfections if any.

I know I'm jumping ahead a bit here, but have you decided on a layup schedule for the hull yet???

yes / no.

i have done a bunch of different test panels, but still not sure exactly what to do... this is something i am dreading.

i'd love some ideas...

i have been using Gordon / Flash-FX's as kind of a "baseline", but after talking to him, don't want to use a core this time around for my first one for fear of delamination as i know he had an issue with that after a couple seasons.

 

[WaveDemon]

maybe I can help with the layup

I have the removed scupper section from a well known hull builder who's name rhymes with hammer.

this is supposed to be a carbon hull but it's really a visual carbon/carbon reinforced hull.

Anyway, I got a couple of pieces of the bottom half of the hull that were cut out for scuppers. I heated them up to burn off the resin and see what the the lay up looked to be

• gelcoat
• chopped mat (maybe 1.5 oz)
• biaxal (looks like 1708)
• biaxal (looks like 1708)
• biaxal (looks like 1708)
• carbon (looks like 12oz)

 

[WaveDemon]

Personally, I hate 1.5 oz mat. I'd rather just go with 3/4 oz, if needed 2 layers of it.

 

[Dustin Mustangs]

Thanks for posting that. I am surprised to see mat on the exterior of the layup. It's lack of strength is much more critical there. Maybe he used it to prevent print through? You could use a veil for that also.

 

[WaveDemon]

Thanks for posting that. I am surprised to see mat on the exterior of the layup. It's lack of strength is much more critical there. Maybe he used it to prevent print through? You could use a veil for that also.

Less print though and more flexibility to form fit the mold better. It's pretty common to have mat as the first layer.

 

[tomski]

Very common for CSM to be used for the first layer with gelcoat. At least 1.5ozs helps prevent print through.

That first layer is important for a quality gelcoated part.

 

[WaveDemon]

BTW, there is still some print trough on this sample.

 

[Roo]

beautiful - thanks for sharing Wavedemon!

Yes, I know when Gel Coat is used, it is common to use chopped mat to fit into all the tight corners/contours, before fabric is laid down.

I agree, I like .75oz chopped over 1.5. I DO know what my mold layup will be:

MOLD LAYUP

• Orange Tooling Gelcoat
• 2 layers .75oz mat
• 3 layers 1.5oz mat
• 2 layers 12oz biax

I may add a layer or two of Corment in there as well, as well as some wood to add sturdiness and bulk to it. Couple layers at a time, don't want it to distort.

Now, for the part layup, here is what I have messed with (picture first, then its schedule after):

Test Panels

• 5.5mm thick
• 3 layers 12oz biax
• 1 layer coremat
• 3 layers 12oz biax

• 4.5mm thick
• 1 layer 5.7oz carbon
• 2 layers 12oz biax
• 1 layer coremat
• 2 layers 12oz biax
• 1 layer 5.7oz carbon

• 5.5mm thick
• 8 layers 5.7oz carbon
• 1 layer coremat
• 8 layers 5.7oz carbon

• 6.5mm thick
• 16 layers 11oz carbon
• big note - the resin i used on this one was VERY high in viscosity - to high for a laminate but all I had to use at the time of this panel. I use/used this resin for making glues/pastes.

I used coremat on these before I had spoken with Gordon about delamination issues. I will NOT use it in the final part, and will replace the thickness of it (about 2mm) with fabric.

I want to make 2 hulls in the end - one glass with a mild drivetrain for the "big water", and one FULL carbon for the 1015cc/flatwater.

 

[Dustin Mustangs]

Are you planning on embedding cores of any sort (foam for example)? Does the rickter have any, and if so, where?

 

[Matt_E]

don't want to use a core this time around for my first one for fear of delamination

I used coremat on these before I had spoken with Gordon about delamination issues. I will NOT use it in the final part, and will replace the thickness of it (about 2mm) with fabric.

Last one was the post directly above yours. :biggrin:

 

[Dustin Mustangs]

Doh!

 

[Idok]

ghostrider thats a big negative on the core

 

[Roo]

lol - nice guys.

the couple spots i have drilled into the rickter, no core. however, i will be drilling a couple holes in the bottom pretty soon here (i'll explain why later). i will be able to tell really quick if they are using a core, and also curious of the thickness.

i highly doubt though that they are. this hull is HEAVY. I believe it so by ALL Biax and Vinyl Ester Resin.

i spoke with Tem / Superfreak on the phone awhile ago about his hulls and he said he was using Divinycell as a core. not sure exactly where he is using it, but food for thought...