Best pad for 4.5" grinder - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > On Board > Gear & Maintenance
 Not a Member? 
  #1  
Old 04-19-2010
davidpm's Avatar
Senior Member
 
Join Date: Oct 2007
Location: Madison
Posts: 3,735
Thanks: 191
Thanked 45 Times in 38 Posts
Rep Power: 7
davidpm is on a distinguished road
Best pad for 4.5" grinder

If I want to cut fiberglass quickly what tools do you recommend.

I usually use a 4.5" grinder (don't have a 7" yet) and have tried different wheels.
The 1/4" masonry, the flap sanders like below.

Lets say you have a 3/4" hull with a hole so you want to grind a taper back 9" what will do the job the fastest?



Amazon.com: 3M SandBlaster 9678 4-1/2-Inch 36-Grit Right Angle Grinder Multi-Layer Disc: Home Improvement
Reply With Quote Share with Facebook
  #2  
Old 04-19-2010
bljones's Avatar
Senior Member
 
Join Date: Oct 2008
Location: South Coast Ontario
Posts: 8,161
Thanks: 32
Thanked 72 Times in 65 Posts
Rep Power: 7
bljones has a spectacular aura about bljones has a spectacular aura about
why the hell would you want to taper a 9" radius around a 3/4" hole? In any event, I would use a die grinder with a cone burr rather than a 4" angle grinder for the heavy work, then change to a small detail sander to finish up.
Reply With Quote Share with Facebook
  #3  
Old 04-19-2010
davidpm's Avatar
Senior Member
 
Join Date: Oct 2007
Location: Madison
Posts: 3,735
Thanks: 191
Thanked 45 Times in 38 Posts
Rep Power: 7
davidpm is on a distinguished road
Quote:
Originally Posted by bljones View Post
why the hell would you want to taper a 9" radius around a 3/4" hole? In any event, I would use a die grinder with a cone burr rather than a 4" angle grinder for the heavy work, then change to a small detail sander to finish up.
Just a hypothetical 12 to 1 taper for a repair, Yes?

Last edited by davidpm; 04-19-2010 at 10:49 PM.
Reply With Quote Share with Facebook
  #4  
Old 04-19-2010
Senior Member
 
Join Date: Apr 2008
Posts: 453
Thanks: 12
Thanked 16 Times in 16 Posts
Rep Power: 7
Hudsonian is on a distinguished road
I take it the hull is 3/4 " thick and that you are trying to acheive a 1:12 bevel aound the hole. For similar projects I have just used a sanding disc on a 4.5" angle grinder. As I recall, I used an 80 grit disc. It works quite quickly. Of course, wear proper protective gear to include long sleeves, eye protection and a respirator
Reply With Quote Share with Facebook
  #5  
Old 04-19-2010
Stillraining's Avatar
Handsome devil
 
Join Date: Jan 2008
Location: LaConner,Washington
Posts: 3,477
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 9
Stillraining is a jewel in the rough Stillraining is a jewel in the rough Stillraining is a jewel in the rough
I agree.... a 80 grit flap disk on your 4 1/2 grinder is killer for this...you will be done in 10 min.
__________________
"Go Simple...Go Large"

Relationships are everything to me..everything else in life are just tools to enhance them.


The purchase price of a boat is just the admittance fee to the dance...you still have to spend money on the girl...so court one with something going for her with pleasing and desirable character traits others desire as well... or you could find yourself in a disillusioned relationship contemplating an expensive divorce.
Reply With Quote Share with Facebook
  #6  
Old 04-19-2010
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,291
Thanks: 0
Thanked 11 Times in 11 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
Quote:
Originally Posted by bljones View Post
why the hell would you want to taper a 9" radius around a 3/4" hole?
To create a proper 12:1 taper to spread the loading of the repair over the hull with. This prevents the repair from having a hard edge and causing future fatigue and stress related problems, since the repair, if made with epoxy resin, is often stronger than the original hull.

Quote:
In any event, I would use a die grinder with a cone burr rather than a 4" angle grinder for the heavy work, then change to a small detail sander to finish up.
Die grinders are awfully good at chewing up a lot of fiberglass really quickly, and too quickly to control the taper well. I seriously doubt that you really need more than 60-80 grit...
__________________
Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
Reply With Quote Share with Facebook
  #7  
Old 04-20-2010
bljones's Avatar
Senior Member
 
Join Date: Oct 2008
Location: South Coast Ontario
Posts: 8,161
Thanks: 32
Thanked 72 Times in 65 Posts
Rep Power: 7
bljones has a spectacular aura about bljones has a spectacular aura about
Ah, crap.
Sorry, david, I had a brainfart. You wrote 3/4", for some reason i read 3/8".
Carry on.
Reply With Quote Share with Facebook
  #8  
Old 04-20-2010
Capnblu's Avatar
Senior Member
 
Join Date: Mar 2006
Location: Squamish
Posts: 659
Thanks: 0
Thanked 4 Times in 4 Posts
Rep Power: 9
Capnblu is on a distinguished road
The disc you show will work great, maybe a little aggressive, so go gently. You will be finished grinding within a minute. Any more than a light pressure will cause alot of hull to be turned to dust! Hold on real good the first time you touch down, you may be startled how much material can be removed by accident.
__________________
Why, why, why?
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

I Don't Know! I Don't Know!
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Tips For Compound, Polish & Wax Maine Sail Gear & Maintenance 242 06-25-2014 11:02 PM
The Salt's Corner Table smackdaddy General Discussion (sailing related) 129 06-18-2013 04:46 PM
Grinder / sander recommendation? cghubbell Gear & Maintenance 18 09-23-2009 09:24 PM
Grinder as Sander? CJV Gear & Maintenance 4 05-19-2005 03:00 AM


All times are GMT -4. The time now is 09:17 PM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.