knobs on glass

[nateswoodworks]

My daughter just turned 8 and love pretty nicknacks so I am going to make her a display case to showcase her little treasures. I want to do fretwork across the top and doors that will not obstruct the view so I am planning on sliding laminated glass doors. A while back she found some pretty ceramic knobs that she wants on the doors and I am thinking it would be best to epoxy the knobs onto the glass. What do you think, any other suggestions, she really has her heart set on these knobs. I had thought about making rubber washers for between the glass and knob and between the screw and the glass as well as an insert for around the screw as it passes through the glass but I just don't know. I am leaning towards the epoxy but would really appreciate some input. Thanks so much for your help.

Nate

[Nick2cd]

i would go with epoxy. even if you can make a perfectly clean bore through the glass (which you should be able to do with a diamond coated tile drill bit), i think you will have less structural integrity issues with the glass if you don't cut a hole through it. however, i recommend properly prepping the glass and ceramic know prior to epoxy'ing them together. i think the best way to do this would be with an acid such as hydroflouric acid. ideally, you want something to etch or frost the glass so the epoxy has something to hold on to (micro-mechanical retention is what we call it in my line of work). you would only need to do this in the small spot where you are placing the knob, and obviously not the entire piece of glass (as it is a display case, of course). you may be able to find the acid by itself, but you would probably have better luck at a craft store and just purchase a glass frosting kit. keep us updated! pics too

[Gregory Paolini]

My daughter just turned 8 and love pretty nicknacks so I am going to make her a display case to showcase her little treasures. I want to do fretwork across the top and doors that will not obstruct the view so I am planning on sliding laminated glass doors. A while back she found some pretty ceramic knobs that she wants on the doors and I am thinking it would be best to epoxy the knobs onto the glass. What do you think, any other suggestions, she really has her heart set on these knobs. I had thought about making rubber washers for between the glass and knob and between the screw and the glass as well as an insert for around the screw as it passes through the glass but I just don't know. I am leaning towards the epoxy but would really appreciate some input. Thanks so much for your help.

Nate

Silicone adhesive works good on glass too - another technique to keep in mind

[TBaiga]

got to add a major safety warning to etching with hydrofluoric acid (HF). besides being one of the more corrosive substances on this planet, HF vapors will pretty much singe all the soft tissue from your nose/mouth, throat and down into your lungs. to add insult to injury, it can eat through most gloves, adsorb through your skin and seek out your bones where the fluoride ions react with the calcium, weakening the bone structure. in a profession lab environment, there are warning lights that strobe in the lab when a cylinder of HF is cracked.

silicon adhesives like the kits used to attach your rearview mirror to the windshield...that's safe. epoxy or drill would be secondary choices.

sorry to be an alarmist, but i know of cases where pros with tons of experience and lots of safety gear were killed. cause of death was pulmunary edema, a hemorrhage event where the victim drowns in his own blood. it only takes a few minutes of exposure to kill you within hours.

[nateswoodworks]

got to add a major safety warning to etching with hydrofluoric acid (HF). besides being one of the more corrosive substances on this planet, HF vapors will pretty much singe all the soft tissue from your nose/mouth, throat and down into your lungs. to add insult to injury, it can eat through most gloves, adsorb through your skin and seek out your bones where the fluoride ions react with the calcium, weakening the bone structure. in a profession lab environment, there are warning lights that strobe in the lab when a cylinder of HF is cracked.

silicon adhesives like the kits used to attach your rearview mirror to the windshield...that's safe. epoxy or drill would be secondary choices.

sorry to be an alarmist, but i know of cases where pros with tons of experience and lots of safety gear were killed. cause of death was pulmunary edema, a hemorrhage event where the victim drowns in his own blood. it only takes a few minutes of exposure to kill you within hours.

Thanks for the warning, I knew it was dangerous but never knew it was that bad! I am slapping myself in the head for not thinking about the rear view mirror before, thanks.

Also thanks to the rest of you who replied, I'll try to post pics as I progress (along with a bunch of pics I already have of other projects) Take care.

Nate

[TBaiga]

no problem. i've lived in a lab for over 25 years and only been to the ER once because of it, and know each day that I am a fortunate soul. good luck on the project and hopefully your daughter loves it!

[Nick2cd]

got to add a major safety warning to etching with hydrofluoric acid (HF). besides being one of the more corrosive substances on this planet, HF vapors will pretty much singe all the soft tissue from your nose/mouth, throat and down into your lungs. to add insult to injury, it can eat through most gloves, adsorb through your skin and seek out your bones where the fluoride ions react with the calcium, weakening the bone structure. in a profession lab environment, there are warning lights that strobe in the lab when a cylinder of HF is cracked.

silicon adhesives like the kits used to attach your rearview mirror to the windshield...that's safe. epoxy or drill would be secondary choices.

sorry to be an alarmist, but i know of cases where pros with tons of experience and lots of safety gear were killed. cause of death was pulmunary edema, a hemorrhage event where the victim drowns in his own blood. it only takes a few minutes of exposure to kill you within hours.

Tom is right. it hydroflouric acid can be nasty stuff. however, i don't believe the stuff you'd get in a glass etching kit is the same molar concentration that Tom is using in the lab. i use it fairly regularly in my job and haven't had any trouble. but of course, be safe and use common sense.