Cutting and drilling Acrylic 1/4" sheet for windows. - SailNet Community
Reply
 
LinkBack Thread Tools
post #1 of 31 Old 04-22-2009 Thread Starter
I don't discuss my member
 
zz4gta's Avatar
 
Join Date: Aug 2007
Location: Chesapeake Bay
Posts: 2,532
Thanks: 0
Thanked 32 Times in 32 Posts
Rep Power: 9
 
Cutting and drilling Acrylic 1/4" sheet for windows.

How can I get a smooth edge on acrylic and drill for screw holes w/o worrying about the sheet cracking? Any special techniques? Thanks.

Merit 25 # 764 "Audrey"
zz4gta is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 31 Old 04-22-2009
Irrationally Exuberant
 
Join Date: Jul 2007
Location: Northern Virginia
Posts: 1,333
Thanks: 9
Thanked 6 Times in 6 Posts
Rep Power: 9
 
I've run a fine flat file lengthwise over the edge to round it out.

Tom K

2000 Beneteau 331
Northern Chesapeake Bay

Ambition is a poor excuse for not having enough sense to be lazy ~ Steven Wright
arf145 is offline  
Quote Quick Reply Share with Facebook
post #3 of 31 Old 04-22-2009
Senior Member
 
Join Date: Jan 2007
Posts: 387
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 9
 
You can use a belt sander to easily shape / even out the edge, etc.

Have you considered using something like 3M VHB tape, as an adhesive, instaed of drilling / using screws / bolts that will leak later. Also use something like Dow Corning 795 or 791 adhesive sealant to keep the water out.

I redid my deadlights using this method "sexy windows" thread on link below.

Very happy with it. They use the 3M tape to hold big windows in skycrapers, etc.
My old frames were through bolted to the cabin, but the acrlyic was just siliconed to the outside of the frame!!! So, now I have the acrylic sealed to the cabin, with no frame, no holes to leak. I tapered the black Dow 795 sealant along the edges, to give it about a 45 degree taper.


Was not able to upload pics here!!

Dscn0808 - Cruisers & Sailing Photo Gallery

new "sexy" windows - Cruisers & Sailing Forums

HOW TO HAVE SEXY WINDOWS!? - Cruisers & Sailing Forums
Northeaster is offline  
Quote Quick Reply Share with Facebook
post #4 of 31 Old 04-22-2009
Just another Moderator
 
Faster's Avatar
 
Join Date: Sep 2005
Location: New Westminster, BC
Posts: 16,546
Thanks: 105
Thanked 314 Times in 301 Posts
Rep Power: 10
     
Wet sanding after cutting with a fine tooth blade on a table saw works, but is a bit labour intensive. There are special drill bits available for drilling plastics, they are worthwhile picking up, also be sure to drill the hole oversize for the fasteners so that you don't stress the hole during expanion/contraction.

We have also had good luck with Dow Corning 795.

Ron

1984 Fast/Nicholson 345 "FastForward"

".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
Faster is offline  
Quote Quick Reply Share with Facebook
post #5 of 31 Old 04-22-2009
Senior Member
 
tommays's Avatar
 
Join Date: Sep 2008
Posts: 4,296
Thanks: 1
Thanked 30 Times in 30 Posts
Rep Power: 7
 
We scrape it by hand with a knife to get a final clear finish

1970 Cal 29 Sea Fever

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

1981 J24 Tangent 2930
Tommays
Northport NY


If a dirty bottom slows you down what do you think it does to your boat
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
tommays is offline  
Quote Quick Reply Share with Facebook
post #6 of 31 Old 04-22-2009
Senior Member
 
jarcher's Avatar
 
Join Date: Jul 2008
Location: Smithfield, RI
Posts: 1,008
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 8
 
Quote:
Originally Posted by Northeaster View Post
Have you considered using something like 3M VHB tape, as an adhesive, instaed of drilling / using screws / bolts that will leak later. Also use something like Dow Corning 795 or 791 adhesive sealant to keep the water out.
Dow 795 and Dow 791 are both silicon based sealents, so if you are planning to seal the acrylic against the fiberglass you may want to consider a different adhesive. As has been discussed here, silicon is bad for fiberglass.

Last edited by jarcher; 04-22-2009 at 12:47 PM.
jarcher is offline  
Quote Quick Reply Share with Facebook
post #7 of 31 Old 04-22-2009 Thread Starter
I don't discuss my member
 
zz4gta's Avatar
 
Join Date: Aug 2007
Location: Chesapeake Bay
Posts: 2,532
Thanks: 0
Thanked 32 Times in 32 Posts
Rep Power: 9
 
How fine should the blade be? I only have a skill saw with a blade I used to put my flooring in. It's fine toothed........for wood.

Merit 25 # 764 "Audrey"
zz4gta is offline  
Quote Quick Reply Share with Facebook
post #8 of 31 Old 04-22-2009
Senior Member
 
jarcher's Avatar
 
Join Date: Jul 2008
Location: Smithfield, RI
Posts: 1,008
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 8
 
Lots of information about 3M VHB Tape here:

http://multimedia.3m.com/mws/mediawe...6EVs6E666666--
jarcher is offline  
Quote Quick Reply Share with Facebook
post #9 of 31 Old 04-22-2009
Senior Member
 
jarcher's Avatar
 
Join Date: Jul 2008
Location: Smithfield, RI
Posts: 1,008
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 8
 
Im in the process of the same job, and I am considering (have not decided yet) using 3M 560 or 540. 3M says:

Quote:
3M™ Scotch-Seal™ Polyurethane Sealant 540 and 3M™ Scotch-Seal™ Polyurethane Adhesive Sealant 560 are one component, moisture curing products which form permanent elastic bonds. They bond to a wide variety of materials including plastics, FRP, SMC, aluminum, steel, coated metal, and wood.
Here is all the data:

http://multimedia.3m.com/mws/mediawe...6EVs6E666666--

The only catch is I only see 540 on sale on their web site, can't find 560. 3M says that 560 has a tensile strength of 580psi and an elongation before break of > 300%. For windows that might be a good strength, although if you want less than the 540 has 250psi and > 800%.

I can't say I know just how strong a dead light bond should be, hopefully someone who knows will chime in
jarcher is offline  
Quote Quick Reply Share with Facebook
post #10 of 31 Old 04-22-2009
Senior Member
 
tommays's Avatar
 
Join Date: Sep 2008
Posts: 4,296
Thanks: 1
Thanked 30 Times in 30 Posts
Rep Power: 7
 
One problem is that the saw will MELT the plastic as you cut SO you need to keep it a bit wet and work slow

Then you can use a sanding block to clean up the edges

1970 Cal 29 Sea Fever

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

1981 J24 Tangent 2930
Tommays
Northport NY


If a dirty bottom slows you down what do you think it does to your boat
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
tommays is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Drilling and Filling Holes in Your Boat Sue & Larry Gear and Maintenance Articles 0 03-11-2003 07:00 PM

Posting Rules  
You may post new threads
You may 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 On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome