Page 1 of 1
Can you "see" the fiberglass through your Gelcoat?
Posted: Sun Aug 03, 2008 6:04 pm
by daydreamerbob
I am hoping that the response to this poll is overwhelmingly yes. I absolutely love my Mac - but always have this anxiety that something is wrong with it. I do think the blisters are due to too thin of gelcoat. I can "see" the fiberglass weave through the gelcoat - in every color on the boat - blue, black, and white. it is especially noticeable in the black. The blue sides are also pretty obvious. I hope this is normal - and that my issues are for different reasons.
So my poll question is - can you see the fiberglass "weave" through the gelcoat on your boat?
Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Sun Aug 03, 2008 7:48 pm
by Chinook
I have noticed seeing sunlight and even the surface of the water sloshing against the outside of the hull, when poking around under the galley counter. It's not everywhere, but just small spots, maybe 1/4 inch across, here and there. I assume it's normal for the method of construction, and not a cause for concern.
Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Sun Aug 03, 2008 7:56 pm
by delevi
That seems quite unusual. I can't see through the gelcoat at all.
Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Sun Aug 03, 2008 10:32 pm
by Québec 1
delevi wrote:That seems quite unusual. I can't see through the gelcoat at all.
Ditto !
Q1
Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Mon Aug 04, 2008 4:38 am
by puggsy
I hope this gives you a bit of an idea....A while ago, I came across a 16ft Canadian canoe and a 19ft kayak, both fairly badly holed, being thrown out as rubbish by two boys. 12/13y.o.
Both were built with "natural coloured" cloth and resin but both looked professionally built. I swapped the two for some cubby building material...of course with their father's permission, and carted them home to repair them. A bit of a hobby of mine...repairing derelict F/G dinghies. With both boats, you could practically see through them, especially the weave and matting...after the holes were repaired, gave them a final coat of orange coloured gelcoat and finished up with solid colour...no more weave to see.
If you are seeing weave or matting, then i would suspect the amount of colour in the final gelcoat was not enough...like painting one colour over another but with the paint too thin...what is underneath always shows through.
puggsy...
'
Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Mon Aug 04, 2008 11:14 am
by baldbaby2000
From what I've noticed on our boat, you can't see through the gel coat.
Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Mon Aug 04, 2008 1:18 pm
by daydreamerbob
Dang - I am not very encouraged by these results so far - The weave pattern is so easy to see on my boat - every where - not 1/4 inch here or there but every where. Sometimes i need to adjust the angle that I am looking but it is very obvious. Maybe my blisters are due to a thinner than normal layer of GC? I mean the blisters are all over the bottom not just here or there.
Also -
I too have seen through the hull - sort of. I was in the aft berth stowing a spare anchor at sunset whit the aft of the boat facing due west. I was able to see the water line in the "rudder gutter" or whatever that channel is called where the rudders are mounted. The whole section was illuminated - pretty cool - or at least i thought at the time.
Please keep voting!
Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Mon Aug 04, 2008 1:24 pm
by daydreamerbob
I also want to clarify what i am seeing - I see the texture or the weave pattern of the glass. Not the glass itself. The boat is completely covered by GC - I icannot "feel the weave" only see it's texture
Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Mon Aug 04, 2008 1:44 pm
by Steve K
I also want to clarify what i am seeing - I see the texture or the weave pattern of the glass. Not the glass itself. The boat is completely covered by GC - I icannot "feel the weave" only see it's texture
I also want to clarify what i am seeing - I see the texture or the weave pattern of the glass. Not the glass itself. The boat is completely covered by GC - I icannot "feel the weave" only see it's texture
Now that you made this clarification, I think most will see what you see, if the look at the boat in the right light.
This means nothing. This patterning can be seen on many boats, particularly in dark colors. It tends to show up more in older boats, mainly due to dulling and shrinking of the gelcoat. I'm pretty sure if any of you look closely, particularly at the black part of an Xboat, you will be able to see a fiberglass weave patterning in the finish. When looking directly at the surface, you may not see it. You have to look at an angle opposite the direction of light hitting the surface, in many cases.
Steve K.
Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Mon Aug 04, 2008 1:50 pm
by Richard O'Brien
typically gel coat is sprayed on very thinly. If you spray it on too thick , it will crack. What counts is the complete soaking of woven fiberglass. When the glass is not soaked and rolled clear through, you can get blisters. Also if the proportion of polyester to fabric is too high , you'll get cracking.
Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Mon Aug 04, 2008 2:00 pm
by Kelly Hanson East
From the inside during daylight, you can see the water line through the FG and gelcoat in every Mac I have ever been on. Nothing wrong here.
Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Mon Aug 04, 2008 2:04 pm
by tangentair
Kelly Hanson East wrote:From the inside during daylight, you can see the water line through the FG and gelcoat in every Mac I have ever been on. Nothing wrong here.
Now I have to go and look the next time, cause I am not sure where I would look cause my insides are all carpeted where I normally look.

Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Mon Aug 04, 2008 2:16 pm
by Oskar 26M
I can see the texture of the weave on the blue part of my M if the light is right. A neighbouring boatie noticed this and commented that it resulted from, and showed that, the boat was built with mat rather than chopped glass - a good think in his (seemingly knowledgeable) opinion...
Re: Can you "see" the fiberglass through your Gelcoat?
Posted: Mon Aug 04, 2008 2:45 pm
by DaveB
The gel. coat on my 1997 Mac. X is suppose to be 20 mills thick (1/32 inches) and is around 10 mills thick in most places and even less on the black in most areas.
I have many voids in cockpit and interior were the layup did not touch the gel. coat causeing pot marks and voids that need to be filled. One area in forward at the two pieces that connect at the fuse panel Port side, had no connection to gel.coat for 3 inches and was 3/16 inches away from fiberglass.
Tho I have read Macgregor has no chopper guns I found evidence of chopper strands in layup. Must have rented one. It was to my understanding these boats were hand laidup and Documented methods in the proccess showing the layup proccess and materials used.(vidio)
Dave
PS: Don't go around putting finger pressure on the gel. coat unless you plan on lots of repairs.