Custom Fiberglass Extended Swim Platform

[tpenfield]

I've always read to understand thinning out the resin is a no no. Just saying.

Yes it is. Sort of messes up the end result. So, keep thinning to a minimum.

 

[tpenfield]

Game plan for this coming weekend (Mar 8-10, 2019)

Friday Eve:

1) Mix TBC to a 10% solution w/ styrene

2) Gel time test of Poly and MEKP @ 2% + TBC @ 300 ppm (0.03%)

Saturday:

3) Gelcoat main platform plug

4) Run another infusion test w/ a thicker laminate and perforated peel ply.

5) 2nd coat of gelcoat on plug

Sunday:

6) Prepare glass and infusion materials for main platform mold infusion

7) Infuse main platform

8) Heat 'soak' platform after infusion to cure

The platform will then have a week or so to cure, as I will be back at work on Monday, then the weekend after, I can add some stiffeners and finally separate the mold from the plug.

 

[kcassells]

Wow...……..I'll just be laying around.
Cool and exciting it is I say!

 

[froggy1150]

Wax dat mold!

 

[tpenfield]

It’s waxed. . . 6 coats, and PVA on the non-skid.

 

[chevymaher]

It’s waxed. . . 6 coats, and PVA on the non-skid.

And no pics. Well that hurts my feelings.

 

[tpenfield]

And no pics. Well that hurts my feelings.

Looks pretty much the same as it did before the wax & PVA . . .

Maybe a bit shinier

 

[chevymaher]

May be true. But when your waiting on parts and living vicariously through others restorations. It is a fix.

Looking good there. Me i am sweating a truck arrival LOL.

 

[mickyryan]

ok so you will make another mold from this mold then that mold will be what you make your final part from?

 

[tpenfield]

ok so you will make another mold from this mold then that mold will be what you make your final part from?

Close, but not quite. . . terminology differences.

This is the 'plug' not a mold. I will be making a mold from this plug and then the final part will be made from the mold.

plug -> mold -> part

 

[mickyryan]

ermagawd i cant imagine what you will have invested after complete but eh it will look awesome

 

[tpenfield]

ermagawd i cant imagine what you will have invested after complete but eh it will look awesome

Yes, it is certainly a long road to the end result.

 

[tpenfield]

TBC inhibitor test update . . .

I did a resin 'pot life' test on MEKP activated poly resin w/ 300 ppm TBC inhibitor, in similar fashion to the other tests that I did a couple of weeks ago.

The TBC inhibited resin started to gel at about 75 minutes and reached a temperature of 150 F at 120 minutes.

So, in summary

0.75 fl oz of resin for each sample starting temperature 55-57 F

2% MEKP gel @ 30 minutes, peak temperature 140+ F

2% MCP gel at 70 minutes, peak temperature 75 F

2% MEKP inhibited by TBC @ 300 ppm gel at 75 minutes, peak temperature 150 F

It looks like the TBC inhibited resin really kicks into gear after the 70 minute open time, where as the MCP activated resin had a similar open time, but did not generate nearly as much heat as the TBC/MEKP combination.

I'm not sure what is best . . . a slow low temperature cure . . . or a presumably faster and high temperature cure. :noidea:

At least I have 2 methods to achieve a 60+ minute working time with the resin.

 

[tpenfield]

The resin hardner/inhibitor test in a picture . . .

Here are the samples from each of the three tests, showing the max temp (exotherm), the working time, and the hardner/inhibitor

​
It is interesting that the MEKP only sample cured a different color than the other 2 samples. The MCP is a combo catalyst/inhibitor (as I understand it), and the MEKP/TBC is 2 separate chemicals. The TBC is added to the resin, then the MEKP is used to activate the resin.

All of the samples cured to a good hardness, but the MCP took the longest to do so.

I'm inclined to use the MEKP/TBC combination as it gives the extended open time, then kicks into gear rapidly.

 

[tpenfield]

Progress update . . .

First coat of tooling gelcoat on the plug.



Not sure if it is orange or red :noidea:

 

[Ciera2450]

Looks almost like the Chevy engine block color. I assume with all this work you will market this swim platform to others with same boat? You’ll have the mold!

 

[kcassells]

$$$ Great Idea there! Recoup.

 

[tpenfield]

Looks almost like the Chevy engine block color. I assume with all this work you will market this swim platform to others with same boat? You’ll have the mold!

IDK . . . the materials alone are about $1K. If I get some interest from others with this boat, then maybe.

 

[dezmond]

Looking really good. I can’t wait to see the mold. Oh the anticipation

 

[tpenfield]

News Flash . . .

I sort of broke the vacuum pump :facepalm:

I ran another test piece, and wasn't paying attention . . . forgot to set up a resin catch pot . . . the pump ate some resin . . . needless to say it did'n't like it. :facepalm:

I have the pump in for emergency surgery, but I'm not sure it will make it

Problem being that I have the 2 coats of gelcoat on the plug and I should be adding resin/glass to it within about 24 hours. If the pump cannot be brought back to life, I'm trying to evaluate some options :noidea:

Hand lay-up ???

Lay-up, then vacuum bag (using shop vac) ???

Other ideas?