Forum Index |  Albums |  Classified Ads |  Catamarans For Sale |  Calendar |  Submit Events
Announcements
New Discussions
Round the world record in trimaran
by northsea junkie. 12/17/17 03:09 AM
Adding a Jib to a Mossie
by Gary Fleming. 12/07/17 11:29 PM
F101 finally in production
by Jake. 12/05/17 06:49 PM
Tradewinds Regatta?
by samc99us. 12/05/17 04:30 PM
Easy way to really learn the Racing Rules
by Mike Fahle. 11/28/17 07:30 AM
Dynema trap lines diameter?
by mmadge. 11/25/17 08:10 AM
foiling chasing UFO
by northsea junkie. 11/23/17 03:12 AM
New Mystere 4.3 in Central Florida
by Mike Fahle. 11/22/17 04:46 PM
36th America's Cup
by waterbug_wpb. 11/21/17 12:10 PM
--Advertisement--
Previous Thread
Next Thread
Print Thread
Rate This Thread
Hop To
Page 1 of 2 1 2
#93119 - 12/21/06 05:51 PM wet sanding question  
Joined: Aug 2003
Posts: 241
papayamon2 Offline
enthusiast
papayamon2  Offline
enthusiast

Joined: Aug 2003
Posts: 241
Largo, Florida
Hi everyone! In my continuing restoration project of an old Trac 14, I'm trying to get the hulls to shine once again. So far I've wet sanded them all w/ 600 grit paper to take out some flaws and clean them up, but I'm wondering how many more iterations of wet sanding are needed? Should I go 1000 then 2000, then buff? Or what? Can I go straight to the 2000 w/out the 1000?

Thanks, and my wife will be glad when this is finally done!

-- Have You Seen This? --
#93120 - 12/21/06 06:03 PM Re: wet sanding question [Re: papayamon2]  
Joined: Apr 2002
Posts: 695
Seeker Offline
addict
Seeker  Offline
addict

Joined: Apr 2002
Posts: 695
Ft. Pierce, Fl. USA
I go 400/600/1000/1500/"buff magic"(compound)with very good results.

Regards,
Bob

#93121 - 12/21/06 11:34 PM Re: wet sanding question [Re: Seeker]  
Joined: Jun 2002
Posts: 1,655
catman Offline
Pooh-Bah
catman  Offline
Pooh-Bah

Joined: Jun 2002
Posts: 1,655
Florida Suncoast, Dunedin Caus...
600 grit will buff fine. Anymore than 1000 is wasting your time.

Use an aggressive compound first then an Glazing compound to finish.


Have Fun
#93122 - 12/22/06 04:06 AM Re: wet sanding question [Re: catman]  
Joined: Feb 2005
Posts: 1,382
Jalani Offline
veteran
Jalani  Offline
veteran

Joined: Feb 2005
Posts: 1,382
Essex, UK
When I've repaired GRP in the past I've always gone 400/600/800/1200 and finished off with G6 cutting compound (fine). For dark colours you sometimes need to follow up with G10. Then buffed with a good quality wax. The results are invariably as good as new.

[Linked Image]

Attached Files
93995-yellowhammer.JPG (64 downloads)

John Alani
___________
Stealth F16s GBR527 and GBR538
#93123 - 12/22/06 04:59 AM Re: wet sanding question [Re: Jalani]  
Joined: May 2006
Posts: 954
Mark P Offline
old hand
Mark P  Offline
old hand

Joined: May 2006
Posts: 954
Mumbles Y.C Wales U.K
Yellow and black striped hulls, must have been bees wax <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />


MP*MULTIHULLS
#93124 - 12/22/06 05:54 AM Re: wet sanding question [Re: Jalani]  
Joined: Feb 2004
Posts: 3,528
scooby_simon Offline
Hull Flying, Snow Sliding....
scooby_simon  Offline
Hull Flying, Snow Sliding....
Carpal Tunnel

Joined: Feb 2004
Posts: 3,528
Looking for a Job, I got credi...
Quote
When I've repaired GRP in the past I've always gone 400/600/800/1200 and finished off with G6 cutting compound (fine). For dark colours you sometimes need to follow up with G10. Then buffed with a good quality wax. The results are invariably as good as new.

[Linked Image]


Hey, John, that looks like an old Condor !


F16 - GBR 553 - SOLD

I also talk sport here
#93125 - 12/22/06 06:56 AM Re: wet sanding question [Re: scooby_simon]  
Joined: Feb 2005
Posts: 1,382
Jalani Offline
veteran
Jalani  Offline
veteran

Joined: Feb 2005
Posts: 1,382
Essex, UK
Quote
Hey, John, that looks like an old Condor !


At the time (1978) it was quite a NEW Condor! <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

So what was the giveaway? - The 'Condor 1978' sticker on the transom? <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

I think it was about 2-3 years old, we'd had a bit of an accident with it and ripped a big chunk out of the stbd hull bottom. The reason for the photo was that I was rather chuffed with the finished repair. Using Jake's 8'/ 5'/ 2' repair standard, it was about a 2" standard of repair! <img src="http://www.catsailor.com/forums/images/graemlins/smile.gif" alt="" />

#93126 - 12/22/06 07:36 AM Re: wet sanding question [Re: catman]  
Joined: Jun 2001
Posts: 12,278
Jake Offline
Carpal Tunnel
Jake  Offline
Carpal Tunnel

Joined: Jun 2001
Posts: 12,278
South Carolina
Quote
600 grit will buff fine. Anymore than 1000 is wasting your time.

Use an aggressive compound first then an Glazing compound to finish.


I've had trouble getting a 600 grit finished followed buffing to sustain a shine longer than a month or so with the Team Seacats blue N20. I'm going to go up a level with the sanding and try buffing again.


Jake Kohl
#93127 - 12/22/06 02:40 PM Re: wet sanding question [Re: papayamon2]  
Joined: Dec 2006
Posts: 16
KenReid Offline
stranger
KenReid  Offline
stranger

Joined: Dec 2006
Posts: 16
Hi group,
I just polished up my new to me 94 Hobie 20 hulls to look like new. On one hull I first used 600,then 3M rubbing compound with a buffer(not orbital) and then I buffed with 3M marine fiberglass cleaner/wax.I used lambs wool pads. On the other hull I just went right to the cleaner/wax. I can not tell them apart.
Happy holidays
Ken

#93128 - 12/22/06 03:04 PM Re: wet sanding question [Re: KenReid]  
Joined: Aug 2003
Posts: 241
papayamon2 Offline
enthusiast
papayamon2  Offline
enthusiast

Joined: Aug 2003
Posts: 241
Largo, Florida
I thought all buffers were orbital (my lack of experience!) I do have a buffer, but it's orbital. Does that matter?

#93129 - 12/22/06 04:29 PM Re: wet sanding question [Re: papayamon2]  
Joined: Feb 2006
Posts: 3,348
fin. Offline
Carpal Tunnel
fin.  Offline
Carpal Tunnel

Joined: Feb 2006
Posts: 3,348
If it were not orbital, it would cut like a grinder so you're MUCH better off.

For future reference, the lighter the color the easier to clean and polish. So, if you have a choice. . .

#93130 - 12/22/06 07:54 PM Re: wet sanding question [Re: fin.]  
Joined: Aug 2003
Posts: 241
papayamon2 Offline
enthusiast
papayamon2  Offline
enthusiast

Joined: Aug 2003
Posts: 241
Largo, Florida
Looks like I'm set, then--my hulls are white!

#93131 - 12/22/06 07:59 PM Re: wet sanding question [Re: papayamon2]  
Joined: Jun 2002
Posts: 1,655
catman Offline
Pooh-Bah
catman  Offline
Pooh-Bah

Joined: Jun 2002
Posts: 1,655
Florida Suncoast, Dunedin Caus...
Orbital won't do it. You need a polishing buffer. If you go out to buy one be careful you don't wind up with a grinder. They look similar.


Have Fun
#93132 - 12/22/06 09:05 PM Re: wet sanding question [Re: catman]  
Joined: Aug 2003
Posts: 241
papayamon2 Offline
enthusiast
papayamon2  Offline
enthusiast

Joined: Aug 2003
Posts: 241
Largo, Florida
Hmm, my buffer says on the label: 10" Polisher, but it's definitely orbital. ??? What sort of motion does the one you're talking about have?

#93133 - 12/22/06 09:35 PM Re: wet sanding question [Re: papayamon2]  
Joined: Jun 2001
Posts: 12,278
Jake Offline
Carpal Tunnel
Jake  Offline
Carpal Tunnel

Joined: Jun 2001
Posts: 12,278
South Carolina
to do real polishing, like catman says, it should look like a side angle grinder but with a rubber head, pad, and wool cover. If you were to leave this one running over one place too long, it will do damage. Should look like this (I've never seen one with a random orbit)

[Linked Image]


A random orbiting buffer (the kind that you find in the automotive section at walmart that mostly vibrates) will do a good job applying wax, but it will not work with rubbing compounds very well at all.


Jake Kohl
#93134 - 12/22/06 09:52 PM Re: wet sanding question [Re: Jake]  
Joined: Aug 2003
Posts: 241
papayamon2 Offline
enthusiast
papayamon2  Offline
enthusiast

Joined: Aug 2003
Posts: 241
Largo, Florida
Hey, who told YOU where I bought my polisher? <img src="http://www.catsailor.com/forums/images/graemlins/smile.gif" alt="" />

#93135 - 12/23/06 08:12 AM Re: wet sanding question [Re: papayamon2]  
Joined: Jun 2002
Posts: 1,655
catman Offline
Pooh-Bah
catman  Offline
Pooh-Bah

Joined: Jun 2002
Posts: 1,655
Florida Suncoast, Dunedin Caus...
I have a Dewalt 849 var. speed. Got it from a local auto paint supply, $100. Use a wool bonnet with the aggressive compound and a foam bonnet with the glazing compound.

Since your local, if you haven't already, you should go down to Fiberglass Coatings in St. Pete. They're on 19 just before 38th ave on left. They have everything you would ever need and are very helpful.


Have Fun
#93136 - 12/23/06 08:59 AM Re: wet sanding question [Re: catman]  
Joined: Apr 2002
Posts: 695
Seeker Offline
addict
Seeker  Offline
addict

Joined: Apr 2002
Posts: 695
Ft. Pierce, Fl. USA
The best pads for the polishers are one piece...they thread right on to the standard 5/8" shaft of the polisher (which all serious polishers share)...they don't have strap on bonnets or rubber backing pads...they are about $18.00-$20.00

Here is what the manufactures rep for "Buff Magic" wrote me...

Our Buff Magic is used extensively by many boat manufacturers for polishing sanded gelcoat for repairs during the production process. All gelcoat sprayed after the fact of being pulled from the mold is sanded, and orange peel is unavoidable, so if yours is slight, you are to be commended on your application skills. Buffing from 400 is not recommended, nor is it a common grit to start buffing from. Most manufacturers buff at a minimum of P600 or finer. And for large areas such as an entire hull, you will highly benefit from going finer, such as P800 or P1000. The time and effort in sanding to a finer grit will save buffing time tenfold compared to the extra time sanding. Using only 400 grit will leave too coarse of scratches requiring much more buffing time and effort, and also will require multiple applications to remove all of the scratches. Multiple applications in addition to being time consuming will degrade the gelcoat beyond what is necessary, and also generates a lot more "heat" which can shrink the gelcoat, and create irregularities, and can cause a "print through effect" of the fiberglass behind the gelcoat. Additionally it is much easier to produce gloss when buffing finer scratches such as P800 or P1000. Buff Magic will work effectively from P600 and finer, but for your application to large areas, P800 or P1000 is recommended.

Jason Brennan
OEM Account Representative

#93137 - 12/31/06 05:26 AM Re: wet sanding question [Re: Seeker]  
Joined: Aug 2003
Posts: 241
papayamon2 Offline
enthusiast
papayamon2  Offline
enthusiast

Joined: Aug 2003
Posts: 241
Largo, Florida
So I finally got around to spending half a day (!!) polishing my hulls. I ended up going 600/1000/1500 on the wet sanding and then polished with a 3M rubbing compound & wax restoration product. I tried polishing from 1000 but wasn't happy with the results, but the 1500 worked great. Very pleased, if I can just keep 'em looking like they do now. Which leads to my next question...

What is a good product to wipe on to keep and protect my hulls so they stay nice and, more importantly, so I don't have to spend another day of my life polishing?

#93138 - 12/31/06 07:58 AM Re: wet sanding question [Re: papayamon2]  
Joined: Jun 2001
Posts: 12,278
Jake Offline
Carpal Tunnel
Jake  Offline
Carpal Tunnel

Joined: Jun 2001
Posts: 12,278
South Carolina
If the polishing job was effective, the shine will hold up well over time. If it wasn't terribly effective, the shine you are seeing is probably more the waxes, oils, and/or fillers that are in the rubbing compound. This is what I'm experiencing with the Team Seacats N20 and why the shine isn't holding up (since I stopped at 600 grit before buffing)

I've had really good results with NuFinish liquid wax - or any of the modern waxes that have UV inhibitors in them. My F18 gets at least two coats a year and it is holding up very well.


Jake Kohl
Page 1 of 2 1 2

Moderated by  Damon Linkous 

Search

Who's Online Now
0 registered members (), 21 guests, and 313 spiders.
Key: Admin, Global Mod, Mod
Newest Members
NilsonPardal, corrinezhan, pussycatcatman, Shotsailor, PointDume
7727 Registered Users
Top Posters(30 Days)
Jake 5
Timbo 3
P.M. 2
Forum Statistics
Forums27
Topics22,269
Posts266,192
Members7,727
Most Online554
May 12th, 2017
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.013s Queries: 17 (0.003s) Memory: 0.9146 MB (Peak: 1.1684 MB) Zlib enabled. Server Time: 2017-12-17 12:06:28 UTC