Dragon/Celtic Tube Issues

[copperstar]

I've had an issue with the tubes of the Dragon and Celtic pen kits.
I'm using the designated drill bit but the holes are larger than the tubes (more than usual), so much so that the tubes fall out after I glue them.
I initially thought my glue was bad. I used new glue and it happened again.
I'm new to these kits and I used acrylic blanks which i'm also new to.
Could this be because of the acrylic? Should I use a drill bit smaller than the recommended?
I was able to re-glue the dragon kit and it held with a lot of glue.
Unfortunately, the Celtic pen has been assembled but is not functioning, I believe because the bottom brass tube is not secured.
Working on the second dragon kit now and same thing.

Any advice or shared similar experience is appreciated.


Thank-you

 

[Sabaharr]

It is possible that you are dealing with a very slightly bent bit. The wobble could enlarge the hole. If the hole it just slightly oversize you may try using epoxy instead of CA (if that is what you are using). It will fill better in a slightly open space and provide a flexible bond. Roll the bit on a flat surface like glass in a picture frame and see if you can detect any wobble.
If you have calipers check the OD of the tube against what the database in the library says it should be. You may have gotten a bad batch of tubes which the supplier should make good.

 

[copperstar]

It is possible that you are dealing with a very slightly bent bit. The wobble could enlarge the hole. If the hole it just slightly oversize you may try using epoxy instead of CA (if that is what you are using). It will fill better in a slightly open space and provide a flexible bond. Roll the bit on a flat surface like glass in a picture frame and see if you can detect any wobble.
If you have calipers check the OD of the tube against what the database in the library says it should be. You may have gotten a bad batch of tubes which the supplier should make good.

Thanks, good information. I'll double check the bit, though it was brand new and appears to be good but I'll do the roll test. I happen to have two bits of this size so I'll also try using the other one.
I haven't used epoxy but will try that...and now I guess I can justify those digital calipers. :biggrin:

 

[KenV]

If the hole is drilling large, one can use a smaller bit and achieve a better fit.

 

[stonepecker]

You could drill it with a smaller bit and then use that as a guid for the right bit. Both bits need to be straight. That wobble test is great but before drilling....Look and see how it is running. If you can see a wobble.......don't use that bit.

 

[jttheclockman]

Nothing says you can not use a smaller bit. It happens many times. Sometimes material drill differently. Find a bit that works for you. That is why it is a good idea to own a complete set of fractional and letter bits.

 

[qquake]

How are you securing the blank when you drill it? In the past, I tried holding blanks in a "gate" jig, but didn't get very accurate holes. I now use a drill press vise with a prismatic jaw, secured to the drill press table. I've made two of the dragon pens, but didn't have any problems.

 

[qquake]

By the way, this is a gate jig. I only use it for holding blanks when I trim them.

 

[randyrls]

The bits listed on the instructions are the closest commonly available bit, NOT the best size. I find that the "suggested" bit is the right one about half the time. Many times, I use a different bit than the one suggested for a better slip fit. I write that size bit on the instruction sheet. A 115 piece drill bit set is a good investment. It has fractional bits, letter bits, and number bits. A metric set completes the set. When you use a bit, make / add a mark on the shank. If the bit you want to use has many marks on it, just go and buy a top quality bit for that size.

 

[WriteON]

How are you drilling? Lathe, jig, free hand?

The Dragon & Celtic are good kits. They should be trouble free.