CAMheads CNC Router Forum By: CAMaster CNC

Go Back   CAMheads CNC Router Forum By: CAMaster CNC > CAMaster Machines > General Discussion

Reply
 
Thread Tools Display Modes
  #11  
Old 03-06-2020, 09:40 PM
Clayton.Lott Clayton.Lott is offline
CAMhead Friend
 
Join Date: May 2019
Posts: 18
Default

Quote:
Originally Posted by Doug S View Post
I use shelf paper on smaller items and let the tool cut they it.
I use this method for cutting signs on raw wood also so I can paint the finished mask and then remove it to expose just the cut letters.
Not sure that would help much in my case as I'm cutting out shaker style doors which will remove most of the film as it's cutting. I only have problems about halfway through a sheet. Up until then it stays pulled down
Reply With Quote
  #12  
Old 03-06-2020, 09:45 PM
Clayton.Lott Clayton.Lott is offline
CAMhead Friend
 
Join Date: May 2019
Posts: 18
Default

Quote:
Originally Posted by Kyle Stapleton View Post
You could just prime it, that would seal it.
Also, you stated that the edges are curling up, have you tried flipping your mdf sheet the curl should go down on a vac table.
Pre priming would be a huge hassle but I've thought about it. Although that may not help since my material doesnt start lifting off the table until about halfway through a sheet. Shaker doors removes alot of material.
Reply With Quote
  #13  
Old 03-06-2020, 09:49 PM
Clayton.Lott Clayton.Lott is offline
CAMhead Friend
 
Join Date: May 2019
Posts: 18
Default

Quote:
Originally Posted by guitarwes View Post
The inherent nature of most any sheet material is to bow, twist, warp, and swell ever so slightly and even worse as humidity and temp changes. Most of the time if I can identify a bow, I will put the crown of the center of the material up. It's easier to pull the middle down than it is to hold bowed edges down.

Maybe Doug is talking about a film mask you can buy to stick over the entire sheet to prevent air from pulling thru.

The next time you have a sheet of MDF on your table to cut, place a smaller piece on top of that one and see how much the vacuum will hold it. The whole thing is a big leak. You just have to have enough CFM to keep up once the seal gets broken. Try applying wide duct tape covering the edges of the material, spoilboard, and plenum all at the same time.
Good idea on the duct tape. May have to try that.
Reply With Quote
  #14  
Old 03-06-2020, 09:56 PM
Clayton.Lott Clayton.Lott is offline
CAMhead Friend
 
Join Date: May 2019
Posts: 18
Default

Update. This morning I started out by doing a fresh mill on my spoilboard. Ran two sheets of mdf making shaker doors with no problem at all. After lunch I started my 3rd sheet and halfway through the edges started lifting up again. Thanks for all the ideas, I am going to try a few of them. Wish me luck.
Reply With Quote
  #15  
Old 03-07-2020, 10:55 AM
Ed Hazel Ed Hazel is offline
CAMaster owner
 
Join Date: Jan 2015
Location: Woodland Mi
Posts: 59
Default

Quote:
Originally Posted by Clayton.Lott View Post
Do you have any issues with the ldh moving with changes in humidity? I may have to check into that.
I don't really do sheet goods so I cant give you a good answer on that.
__________________
Ed Hazel

508 Cobra ATC
Reply With Quote
  #16  
Old 03-07-2020, 12:59 PM
rcrawford rcrawford is offline
Cobra Owner
 
Join Date: Dec 2011
Location: Alberta
Posts: 2,374
Default

Quote:
Originally Posted by Ed Hazel View Post
What does your vacuum pull with the spoil-board uncovered? When I first got my hurricane hooked up I discovered my bleeder MDF was not a good choice. It was taking 6-7HG just to get through the bleeder board which only left 2-3HG for actual "holding" force.

I got some LDF and that worked much better.

Your vacuum gauge SHOULD read high with just the spoil board over the plenum. You aren't "using" 6-7"hg here, you are maintaining 6-7" hg. That is the whole point of the mdf spoilboard. You want enough resistance to airflow so that you maintain low pressure under your workpiece even if there are areas of the spoilboard that are uncovered. It doesn't matter how 'slowly' the air passes through the spoilboard, all that matters is that there is a low pressure area under your workpiece.

Now if your workpiece covers the whole spoilboard, then having it more porous (using LDF) does not matter. But if you are cutting through in lots of areas you want to maintain that low pressure even with the spoilboard uncovered.
__________________
Russell Crawford
Cobra 408 ATC with recoil
Alberta, Canada
www.cherryleaf-rustle.com
Reply With Quote
Reply

Thread Tools
Display Modes

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

Forum Jump


All times are GMT -4. The time now is 05:59 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.