Aluminum failure

[Timbo]

After I got the brass thing worked out (thanks to you guys), I thought Aluminum would be cinch...no such luck. I had a nice peice of black and white ebony, that segmented with blank/white pickguard, and aluminum. The aluminum separated the wood and the pickguard material. I used think CA to glue it all up, and didn't get back to it until the next day. I trimmed off the excess inlay on the bandsaw, and got to drilling...that's when things went downhill. The segments began to separate at the aluminum facings...both the wood and the pickguard sides. I know plenty of folks use aluminum without problems, so what did I do wrong. I prepard the aluminum by roughing it up with sandpaper before the glueup. As a matter of fact, you sould see the scratch pattern from the aluminum in the dried CA on the wood facing.

 

[Ligget]

I would use thick CA for gap filling properties, this may fix the problem!

 

[JohnU]

Ive had problems like this when I used a duller drill bit and forced the drilling a little to hard. Another problem Ive had is when sanding or drilling and getting the aluminum to hot which reacted to the glue and allowed it to break apart. Not sure if any of this contributed to your problem but its something to think about.
Also, I used medium when I glued. Good Luck!

 

[follow3]

I bet if you swtched to epoxy it would work fine.

Steve

 

[desert1pocket]

I've done a lot of segmenting with aluminum and copper. After having many many failures, I have to agree with follow3 that epoxy is the better choice. High temp epoxy would be the best choice IMHO. Also, after roughing the metal up did you wipe off all of the metal dust with a solvent?

Even prepping things well and using epoxy, the drill bit needs to be sharp, and you need to be extra careful how hot things get as you drill it.

 

[jwoodwright]

I agree with the epoxy, as you basically have a butt joint and very little glue surface. Also the sharp drill bit, proper speed and watching the heat build-up....

 

[Mudder]

You mentioned Ebony. Did you use anything to clean off the natural oils on the wood? That could have contributed to your problem.

 

[Timbo]

Thanks for all the help guys! After reading all the responses, I believe the failure was due to a combination of heat build up, not using the best quality bit, and not using the most appropriate adhesive. I don't give up easy. The bits I have, have been working fine in my flatwork. It's obvious now that drilling a segmented blank with a large diameter bit is somewhat more demanding, I just broke down and purchased a new set of HSS bits from MSC Industrial supply. I'll also be getting some epoxy for my next attempt. Any recommendations for type and/or brand? Although i thought I was going slow, I'll go even slower next time.

To answer your question Mudder...in all cases the CA failed on the aluminum side of the joint, oily wood was not the problem.

 

[workinforwood]

I'm going to suggest adding some water into the mix. Epoxy and CA can fail from too much heat. Drill a 1/4" then fill with water, drill another 1/4 add more water and so on. Takes a bit, but it works for me with segments as well as with acrylics which sometimes seem to melt as they drill which elongates the hole. Aluminum builds heat super fast, and disipates heat pretty fast too.

 

[Dave Talbot]

Brass Failure - Celtic Knot

Experimenting with BRASS INLAY (2x10 mil) for Celtic Knot. I know this is pushing it so far as thickness is concerned. Any guidelines for drilling, gluing and clamping? My first attempt to drill the blank resulted in a disaster. I used a parabolic bit and did not place the knot far enough down into the pen vise. Voila! The butt joints of the knot did not hold and the wood blank sort of exploded at the knot. I know I forgot to rough up the brass sheet before gluing with medium CA. Next time I'll rough it up and use epoxy. Previous results with all-wood knots worked out fine as long as the drill was properly centred in the blank.

H E L P!

 

[JerrySambrook]

Dave,
I did respond to your thread.
Jerry

 

[leehljp]

Jeff mentioned water and 1/4 inch at a time. I know you fellow want to get on with making segments. Don't look for the end results but the process, the journey. If it takes 30 minutes or 1 hour to drill so that it does not separate, would it be worth it to you?

It may not take that long, then again, it could take longer. Patience is a virtue with segments. Gradually speed up the drilling if needed on later pens, as experience is gained.

 

[jttheclockman]

I too use epoxy and when doing metal inlays I use the step drilling method. I sneak up on the proper hole by starting with a smaller drill bit and taking it up in steps. I use denatured alcohol to cool my bits when drill acrylics as well as metals.

 

[johncrane]

Wrap the knot with string then soak it with thin ca,
cover your eyes,and use a fan too blow the fumes away.