1

Topic: Magnetic Glass Bed Mounting

Okay I've been kicking this idea around for a while and finally got time to try it out.  Whole thing only takes 1/2 hour and the materials are about $10 if you don't already have them.   Bed size is 6" front to back, 7.5" left to right.

First buy the glass and some hanger strap, this can be found in the plumbing section of your hardware store, or holding up the rails on your garage door.  I used a lock washer on mine, don't know if it's necessary or not.

http://s2.postimage.org/mr6rxvvm1/hanger_strap.jpg

Drill a couple holes into the wood platform, cut the strap with tin snips longer than necessary.  I just marked the first one with a pencil and used needle nose pliers to bend it by hand.  You'll want to keep it a bit below the surface of the magnet.  Here's the view from below and a profile shot of the brackets.

http://s2.postimage.org/n19p3hkuh/bracket_bottom.jpg
http://s2.postimage.org/xcqn9w1xl/bracket_profile.jpg

I just super glued (4) 1/2 dia X .030" thick earth magnets to the underside of the glass.  My method was to lay the glass down, stick electrical tape over the spots on the brackets where the magnets needed to be and then flip over and glue. 

Here's the finished product, the warning I have is to keep the bracket length inside the glass.  My back left bracket was only about .030" from hitting the X motor on my test print.  I had to trim it down. 

Glass bed is 6" front to back, 7.5" left to right.  Bonus area to print on if you wanted.  It's not the lock like clips give you, but there shouldn't be pressure on the glass during a normal print as far as I can see, so it's snug enough to print on and not so locked that you distort your brackets putting them on and off.  Stronger magnets would work as well if you're worried about it or doing something I can't forsee. 

http://s2.postimage.org/kb4yk1djd/installed.jpg

2

Re: Magnetic Glass Bed Mounting

Really neat solution!

3 (edited by cmetzel 2013-03-01 16:10:55)

Re: Magnetic Glass Bed Mounting

Superglue is not strong enough or is failing due to heat, anyone have suggestions to keep the magnets secure?

EDIT:  This has been solved, I'm using JB Weld now and it's working perfectly, stop suggesting glues. haha

4

Re: Magnetic Glass Bed Mounting

What about Oven Door Glue
http://ovendoorglue.com/

5

Re: Magnetic Glass Bed Mounting

I've never gotten superglue to work.. ever!
Well, it does work eventually to hold the bottle cap on permanently  tongue

Surely scratching the surfaces and a healthy glob of 5-minute epoxy would do the trick?

6

Re: Magnetic Glass Bed Mounting

Could always consider something like jb weld or another automotive epoxy that doesn't mind heat.

7

Re: Magnetic Glass Bed Mounting

yeah I was thinking jb weld, but would it stick to glass?

8

Re: Magnetic Glass Bed Mounting

a mate used superglue to hold signs on his shop windows the night before opening, in the morning the signs where on the ground with a little cone shaped chunk of glass in each corner. It supposedly gets into the glass and shrinks shattering it, needed to get 10 very thick expensive windows replaced on opening day, was not popular with the big bosses.

i would try liquid nails personally..

9

Re: Magnetic Glass Bed Mounting

Some high temp RTV from an automotive store would work pretty good for this application I think. it's good for over 300C

http://www.ebay.com/itm/PRO-SEAL-80726- … mp;vxp=mtr

or even some non-high temp is still good to over 200C

http://www.ebay.com/itm/BRAND-NEW-PRO-S … mp;vxp=mtr

10

Re: Magnetic Glass Bed Mounting

Right now I've got JB Weld on it with stronger magnets.  I've only printed a few items with it since the JB weld so it's too soon to say if the heat cool cycle will weaken the bond.  Seems okay now. 

However I tried JB weld on plexiglass to magnet joint.  I applied it before bed and let it sit, and in the morning the magnets were loose.  I don't know why they gave out like that on plexiglass.  I printed a clip to contain the magnet and go over the edge of the door but I would rather just have the clean look of the magnet itself.

11

Re: Magnetic Glass Bed Mounting

I liked your magnet mounting idea, and I had some spare magnets from the fan duct mount/indicator mount so I made this: http://www.thingiverse.com/thing:54297 . I found that holding the magnets in this direction made the bed less prone to sliding.

12

Re: Magnetic Glass Bed Mounting

Looks good, thanks for the shout out.  I've been using mine without incident now for a while.  When you think about it, there shouldn't be any lateral forces on the part unless something has already gone wrong.  There may be a slight dragging if your flow is too high but it shouldn't be enough to knock the bed loose. 

The only problem I have with the whole idea is it's hard to handle the glass around the desk because tweezers and exacto knifes and screws etc all come running for the magnets.  haha

13

Re: Magnetic Glass Bed Mounting

Try Gorilla glue, found in most hardware, walmarts,etc by the paint.  That stuff sticks like crazy to just about anything.

14

Re: Magnetic Glass Bed Mounting

JB Weld was used and is holding since about Jan 12th or so.

15

Re: Magnetic Glass Bed Mounting

I'm going to have to try this. I tried glass tonight, and stock bed turned out to be way too warped to even clip to.

Am I correct in that this completely steps around using the leveling screws, and the glass just contacts the middle of the stock bed, and that you level by adjusting the metal straps by pliers?

16

Re: Magnetic Glass Bed Mounting

It would be easier and more precise to still level with the screws from under the bed.

17

Re: Magnetic Glass Bed Mounting

cmetzel wrote:

Superglue is not strong enough or is failing due to heat, anyone have suggestions to keep the magnets secure?

the magnets used to clean fish tanks.

one on top, one on the bottom of each hanger strap?

18

Re: Magnetic Glass Bed Mounting

danny wrote:
cmetzel wrote:

Superglue is not strong enough or is failing due to heat, anyone have suggestions to keep the magnets secure?

the magnets used to clean fish tanks.

one on top, one on the bottom of each hanger strap?

I don't think people are reading the thread all the way.  I think I've said 3 times that I'm using JB Weld and it's working great.  Thanks but this is no longer an issue.

19

Re: Magnetic Glass Bed Mounting

Drew Diller wrote:

I'm going to have to try this. I tried glass tonight, and stock bed turned out to be way too warped to even clip to.

Am I correct in that this completely steps around using the leveling screws, and the glass just contacts the middle of the stock bed, and that you level by adjusting the metal straps by pliers?

No this has nothing to do with leveling.  It's just a method of being able to remove the print and start a new one without having to peel it off the stock bed. 

The metal straps give a little, I have mine set down about 1/16 under the magnet and it pulls them up keeping downward pressure on the glass during the build.  Haven't had one shift yet in a month or more of using it.