Corian blow up!

[keithbyrd]

I segmented 4 peices of 1/2 corian - length wise and used aluminum from a coke can and 5 min epoxy Quick Set. I let it cure for 2 days. I started out to drill a pilot hole using 6 mm bit - 1/16 from the end of the hole it blew up! I did this with 2 pieces. I CA'd it back together and tried again - no luck still blew up.!
I was using and air gun and blowing air down the hole as I was drilling and frequently checked the drill temp - never really got hot.

What is the trick?

 

[JohnGreco]

I'd try some sort of clamping set-up that applies pressure inward on all 4 sides, or tape it up prior to drilling at the very least. GL!

 

[keithbyrd]

I'd try some sort of clamping set-up that applies pressure inward on all 4 sides, or tape it up prior to drilling at the very least. GL!

Do you mean when I glue it together? I used clamps and let it set for two days?
Do you mean during drilling I used the new Nova Pen jaws which clamp on 2 sides. Thought I had that covered!

 

[carlmorrell]

Are you actually trying to drill all the way through the bottom of the blank? I never do that. Cut the blank longer than needed. Do not drill all the way through. Then cut the bottom off, to reveal the end of the bore.

 

[kruzzer]

What Carl said....

 

[jttheclockman]

I will give you my take on the situation. I looked at the photo and photos serve to tell a story most of the time that the OP does not state.

First off air will not cool a bit. Not sure who started that one. You have 2 materials that will generate alot of heat when drilled. Corian which is basically an acrylic and aluminum that is being drilled LENGTHWISE. Wow that is pushing the envelope. Not saying it can't be done, just will take some finesce. You need to cool the bit some other way. I like to use denatured alcohol after I pull the bit out after some drilling. You can shoot some air to clean the debris. It can not hurt.

The next thing I looked at is where is the glue??? You have to be very careful when glueing pieces together that you do not overclamp and thus starve the joint of glue. This is one reason it is recomended to rough edges and faces abit when gluing. It forms sort of channels for glue to adhere to. When you switched to CA you were basiclly gluing glue to glue(epoxy residue)

I cringe everytime people mention they use coke cans for their inlays. For mere pennies you can get some sheet aluminum from your Home Centers. It is flat and easily sanded to roughen up. With coke or other beverage cans you have films that were applied and if not wiped off or sanded off you have potential for failures. After I sand and just before I start my glueups I wipe the aluminum down with acetone. Works for me.

Finally the point about blowouts on the ends has been mentioned here thousands of times and one simple way around it is to make the blank a bit longer and not drill all the way through but cut the end off. Also if the blank is fragile it has been suggested also to wrap the blank in guaze or wood splints or some other method to give strength to the outside pushing forces when drilling.

Just some of my thoughts. Good luck.

 

[keithbyrd]

Thanks for all the comments - good ideas/tips - John thinks for the detailed analysis - I appreciate the insights. I think you are right on - I will modify my process and try again!

 

[mikespenturningz]

I have used many coke cans for aluminum but you have to really rough it up and the same with any other aluminum. I use 80 grit for roughing up all of my aluminum. Also as John said rough up the corian also. Think of it as adding to the surface area that you are glueing. I have however not drilled only part way through and cut the end off? I have had blanks let go on the exit of the drill but it isn't all that often? Usually if I make it that far I am pretty much done? There is no real silver bullet for segmenting it takes experience and the making of mistakes. I have made my share of them but have learned from most of them. What you are doing is definitely something that can be done but you have to remember that when you are drilling like that with the aluminum going with the drill you may want to drill very slowly. I have also found that some extra speed seems to be easier on the blank for the smaller drills. If you are not drilling in multiple steps you will absolutely need to do that.