Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 03-04-2013, 14:27   #16
Registered User

Join Date: Mar 2011
Posts: 253
Quote:
Originally Posted by minaret
Suppose ill just mention the many threads in which I've mentioned using an 8" soft pad sander for this. Do you think the gelcoat is sprayed to exactly the same thickness everywhere in the mold? It's not, at all. Therefore if you just sand till the gel is gone you will be creating severe unfairness. This is what a peeler is designed to prevent.
That's one thing I had not thought about. Thank you!
__________________

__________________
shamrock is offline   Reply With Quote
Old 03-04-2013, 14:51   #17
Registered User
 
zboss's Avatar

Join Date: Sep 2011
Location: On a boat
Boat: Cabo Rico 38
Posts: 3,426
Re: Hull Peelers Vs. Sanding

Quote:
Originally Posted by minaret View Post
Does nobody EVER use the search function? I've made so many posts on this subject, I give up...
The search function on this site is useless for a couple of reasons...

1) never-ending threads. 20,000 responses - really? And I am expected to dig through all those pages to find the one response that I am looking for?

2) Multiple question and Responses - like this one - interwoven throughout threads.

It takes FOREVER to find responses for information.

3) misunderstanding of what forums are. Forums are just that... a forum... not a library. A more suitable response to information seekers is to search for how-to's using google and whatnot.

4) Never ending streams of BS. There I said it.
__________________

__________________
zboss is offline   Reply With Quote
Old 03-04-2013, 17:24   #18
Resin Head
 
minaret's Avatar

Cruisers Forum Supporter

Join Date: Aug 2007
Location: Seattle WA
Boat: Nauticat
Posts: 7,201
Images: 52
Re: Hull Peelers Vs. Sanding

Quote:
Originally Posted by shamrock View Post
Thanks.

I am using a Bosch sander with a vacuum attachment. This is a pretty amazing tool. Virtually no dust but I do wear a full face 3M cartridge respirator.

Bosch 1250DEVS 6-1/2-Amp 6-Inch Random Orbit Sander with Vacuum Port - Amazon.com

As the Amazon reviews say, it removes a ton of material pretty quickly.

There is a switch that makes the pad spin like a grinder, but I feel like I am damaging the surface and definitely creating divots. It's also a real handful to control when not in orbitat mode.

My blisters are all very small/ shallow and limited to just beneath the gelcoat.

I'm not really confident that I would be able to fair the surface if I did create divots with a grinder, using a long board after grinding seems like it would be much more work then what I am doing now.

I just got the 40 grit discs and will be back at it tomorrow morning before work!

I'll take the time to discuss this yet again. The reason you are getting divots in grinder mode is because a DA is not designed properly for this. Most have a side switch, it's either on or off, even if you have variable speed. This is not OK for grinding. You MUST have a trigger to grind properly. This is why some of the newer grinders with a deadman switch suck. Only a trigger will allow you to grind properly. The trigger must be feathered with each stroke of the grinder, in exactly the same fashion that a painter sprays paint, and for the same reason. If a painter just held the trigger down while shooting, he'd get a hanger at either end of his stroke due to the moment of dwell created by the direction change at the end of the stroke. Same thing happens with a grinder, but instead of a hanger you get a divot. So, just like a painter, a grinder should only be depressing the trigger in the middle of each stroke. That way at the ends of your stroke the grinder motor is off and the disc is decelerating. Once this technique is mastered you will realize the same method can give you dramatically more control in fine contour grinding and your grinding skillz will go through the roof. Trigger locks and switches are for amateurs, true grinding pros use grinders with triggers. It's twice as much work, your trigger finger will become ripped, and the results are quite superior, especially on compound shapes and detail grinding.
__________________
O you who turn the wheel and look to windward,

Consider Phlebas, who was once handsome and tall as you.
minaret is offline   Reply With Quote
Old 03-04-2013, 17:32   #19
Resin Head
 
minaret's Avatar

Cruisers Forum Supporter

Join Date: Aug 2007
Location: Seattle WA
Boat: Nauticat
Posts: 7,201
Images: 52
Re: Hull Peelers Vs. Sanding

Quote:
Originally Posted by shamrock View Post
That's one thing I had not thought about. Thank you!


No problem. Having built a lot of boats, I can tell you the gel is usually twice as thick at certain areas like the turn of the bilge, because of the angle which you are spraying gel at. It also tends to be much thicker in tight areas like the stem and the keel cavity/stub, as well as at any geometry like radii. Sometimes a booth operator will do things like shooting excess gel into a section of the mold instead of dumping it, creating a thick spot. Just removing the gel is generally a really bad idea.
__________________
O you who turn the wheel and look to windward,

Consider Phlebas, who was once handsome and tall as you.
minaret is offline   Reply With Quote
Old 04-04-2013, 09:38   #20
Senior Cruiser
 
Cheechako's Avatar

Cruisers Forum Supporter

Join Date: Aug 2006
Location: Skagit City, WA
Posts: 19,366
Re: Hull Peelers Vs. Sanding

Quote:
Originally Posted by minaret View Post
Suppose ill just mention the many threads in which I've mentioned using an 8" soft pad sander for this. Do you think the gelcoat is sprayed to exactly the same thickness everywhere in the mold? It's not, at all. Therefore if you just sand till the gel is gone you will be creating severe unfairness. This is what a peeler is designed to prevent.
I dont know, "you da man" when it comes to this stuff, but I've seen a lot of peeler ridges far worse than anything he's going to get with the orbital. Just depends on the operator I guess. The OP's approach is incredibly slow, but if it works for the non-boatyard type of guy and he doesnt mind doing it's probably not a bad way to go. I wouldnt have the patience or arm endurance! Seen quite a few boat owners approach it that way though.
__________________
"I spent most of my money on Booze, Broads and Boats. The rest I wasted" - Elmore Leonard











Cheechako is online now   Reply With Quote
Old 06-04-2013, 18:18   #21
Registered User

Join Date: Mar 2011
Posts: 253
So, I am making some good progress. The biggest challenge Is dealing with the curves, particularly above the keel. I started using a small triangle detail sander, but I'm thinking that a really soft sanding pad on a grinder might work better?

The picture is about 8-9 hours of sanding a coupke of mornings and one day after work.
Attached Thumbnails
Click image for larger version

Name:	image-3222734473.jpg
Views:	230
Size:	205.9 KB
ID:	58693  
__________________
shamrock is offline   Reply With Quote
Old 06-04-2013, 18:27   #22
Resin Head
 
minaret's Avatar

Cruisers Forum Supporter

Join Date: Aug 2007
Location: Seattle WA
Boat: Nauticat
Posts: 7,201
Images: 52
Re: Hull Peelers Vs. Sanding

Quote:
Originally Posted by shamrock View Post
So, I am making some good progress. The biggest challenge Is dealing with the curves, particularly above the keel. I started using a small triangle detail sander, but I'm thinking that a really soft sanding pad on a grinder might work better?

The picture is about 8-9 hours of sanding a coupke of mornings and one day after work.


Bottom Paint Question
__________________
O you who turn the wheel and look to windward,

Consider Phlebas, who was once handsome and tall as you.
minaret is offline   Reply With Quote
Old 06-04-2013, 20:01   #23
Registered User
 
sabray's Avatar

Join Date: Aug 2008
Location: Wash DC
Boat: PETERSON 44
Posts: 3,169
Re: Hull Peelers Vs. Sanding

Im thinking your kidding. I cant get through bottom paint in that time. I would look like a red smurf. I couldnt post anything unless CF allowed using language that only works in a roadhouse full of convicted, felonious, hairy women drinking carp snot. Jeez man. Im like sanding discs stuck in my hair I have streaks of goo in my nasal passages.
You are like that was fun.
__________________
sabray is offline   Reply With Quote
Old 07-04-2013, 10:50   #24
Registered User

Join Date: Mar 2011
Posts: 253
Quote:
Originally Posted by minaret
Minaret,

I just bought the 6088 grinder.

What flexpad specifically do you recommend to do the bilge area?

Do you change them during jobs, or just use the same one for the whole bottom?

Thanks!
__________________
shamrock is offline   Reply With Quote
Old 07-04-2013, 11:12   #25
Registered User

Join Date: Mar 2011
Posts: 253
Quote:
Originally Posted by sabray
Im thinking your kidding. I cant get through bottom paint in that time. I would look like a red smurf. I couldnt post anything unless CF allowed using language that only works in a roadhouse full of convicted, felonious, hairy women drinking carp snot. Jeez man. Im like sanding discs stuck in my hair I have streaks of goo in my nasal passages.
You are like that was fun.
Haha! Not fun. My arms are about to fall off!
__________________
shamrock is offline   Reply With Quote
Old 07-04-2013, 14:52   #26
Resin Head
 
minaret's Avatar

Cruisers Forum Supporter

Join Date: Aug 2007
Location: Seattle WA
Boat: Nauticat
Posts: 7,201
Images: 52
Re: Hull Peelers Vs. Sanding

Quote:
Originally Posted by shamrock View Post
Minaret,

I just bought the 6088 grinder.

What flexpad specifically do you recommend to do the bilge area?

Do you change them during jobs, or just use the same one for the whole bottom?

Thanks!

Nice, though if you read further you'll find that I think the standard Makita buffer is sometimes a better choice for small bottom jobs like this. It's lighter, and you should own one for polishing and buffing anyway. The 6088 is only good for heavy sanding and grinding, great tool but maybe overkill for a single bottom. Still, they're pretty cheap.
I assume you mean the turn of the bilge, that being one of the classic problem areas. Depending on the shape of the boat, I will occasionally go to a softer pad. The thread I linked earlier has links to a variety of pads. More often I go to a 10,000 for that area. That's a standard 10,000 RPM Milwaukee electric grinder with a 5" soft pad on it. This allows you to sand 36 grit like a DA but still feather the trigger like a grinder.
It's hard to explain how to properly grind this area, although easy to show someone in the flesh, but I'll try. Hold your soft pad at a 90 degree angle to the hull with the radius of the pad in the radius of the turn of the bilge. Change your pad size to fit as close as possible the radius of the hull, either 8" or 5". Often, especially on smaller boats like this, the radius made by the turn of the bilge will be too tight for either. Select the best size for the job, hold it in place at an angle, and then rotate the handle of the grinder until the pad radius fits right into the hull radius. This is the angle of pitch, roll, and yaw you should be grinding at. Stroke it out with one way strokes while feathering the trigger. Obviously, the proper angle changes as you move fore and aft. A little practice will allow you to grind this area with no divots or "scalloping". Another option is to use a large piece of soft foam which will conform to the hull, stick an 8" 36 grit pad too it, and scrub away until the gel is gone. Use spray adhesive for this. I often finish up after machine sanding this way anyhow. Hope that makes sense and is helpful, ask away if it doesn't.
__________________
O you who turn the wheel and look to windward,

Consider Phlebas, who was once handsome and tall as you.
minaret is offline   Reply With Quote
Old 08-04-2013, 23:29   #27
Resin Head
 
minaret's Avatar

Cruisers Forum Supporter

Join Date: Aug 2007
Location: Seattle WA
Boat: Nauticat
Posts: 7,201
Images: 52
Re: Hull Peelers Vs. Sanding

Here's a lame vid of me grinding while trigger feathering. Lots of edges and detail grinding here, on a bottom bigger strokes and different technique is required. But trigger feathering is key to good grinding regardless. In this vid the grinder never really winds up to full speed, the motor is off as much as on for the most part. Often I'm barely depressing the trigger.





__________________
O you who turn the wheel and look to windward,

Consider Phlebas, who was once handsome and tall as you.
minaret is offline   Reply With Quote
Old 09-04-2013, 10:46   #28
Registered User

Join Date: Mar 2011
Posts: 253
Quote:
Originally Posted by minaret
Here's a lame vid of me grinding while trigger feathering. Lots of edges and detail grinding here, on a bottom bigger strokes and different technique is required. But trigger feathering is key to good grinding regardless. In this vid the grinder never really winds up to full speed, the motor is off as much as on for the most part. Often I'm barely depressing the trigger.

Very helpful, thanks! I'll post photos and let you know how it goes
__________________
shamrock is offline   Reply With Quote
Old 09-04-2013, 11:14   #29
Marine Service Provider
 
Tony B's Avatar

Join Date: Jul 2011
Location: Presently in Rogersville, Al
Boat: Mainship 36 Dual Cabin
Posts: 695
Re: Hull Peelers Vs. Sanding

When I lived in Biloxi, Ms during the early 2000's, several people had their boat peeled by 2 different guys. maybe these guys didn't know what they were doing, but they sure left a surface much less than ideal. In every case, the boat owner spent lots and lots of time re-glassing and fairing. Some even extended their boatyard stay a few months extra.

If you have access to at least a 60 gal. air compressor, you can use a flap sander like they use on cars.
__________________
Mainship 36 DC - 1986
Retired and Full Time Cruising the Eastern U.S. inland Waterways
www.FreeBoatProjects.com
Tony B is offline   Reply With Quote
Old 09-04-2013, 16:12   #30
Senior Cruiser
 
Cheechako's Avatar

Cruisers Forum Supporter

Join Date: Aug 2006
Location: Skagit City, WA
Posts: 19,366
Re: Hull Peelers Vs. Sanding

Yeah, I've seen terrible ridges, but more lately I've seen some peels that look superb. Depends on the tool and operator I guess.
__________________

__________________
"I spent most of my money on Booze, Broads and Boats. The rest I wasted" - Elmore Leonard











Cheechako is online now   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 10:38.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.