[Nordicus]

Greetings heretics!

I've found myself in a bit of a pickle - I'm hoping one of you have a link or knowledge that I just can't find.

Now, I have a hobby drill that supports up to 3 mm drillbits, for those magnetizing jobs. However, I find that certain things (Such as wingson a dragon) requires a magnet that is 4mm in size. The problem is that I can't seem to find a hobby drill that supports higher than 3 mm. Ìt's a pain doing it by hand and it often makes the job very unprecise if I'm not really careful.

Am I missing something or is it simply impossible to find one which supports higher than 3 mm in drillbit sizes?

 

[Wookiepelt]

The way I do it is to pre-drill with the smaller drill bits, starting with the 1mm for a precise location for the centre of the hole. After that, simply step up with the drill bit sizes (to a 2mm and 3mm using the hand drill) and enlarge the hole by using the initial smaller hole as the pilot guide. By the time you get to the 3mm hole size, any large size requirement can be easily accomplished with the standard drill bits without the need for a holder. Having said that, I do apply a few masking tape layers on the holding shank of the larger drilling bits for a better finger grip.

PS: This method is a standard way for drilling large holes on wood and metal to avoid over stressing the drill bits and the drilled component (especially so with bits on metals, and prevent softer components, i.e. plastics & resins, from uncontrolled tearing!).

 

[Nordicus]

The way I do it is to pre-drill with the smaller drill bits, starting with the 1mm for a precise location for the centre of the hole. After that, simply step up with the drill bit sizes (to a 2mm and 3mm using the hand drill) and enlarge the hole by using the initial smaller hole as the pilot guide. By the time you get to the 3mm hole size, any large size requirement can be easily accomplished with the standard drill bits without the need for a holder. Having said that, I do apply a few masking tape layers on the holding shank of the larger drilling bits for a better finger grip.

This is the way I do it now, but i still find the plastic/resin to be under more pressure, than if I do it by drill. Last time something broke, as I had to turn so hard for the drill to not just be stuck halfway through, and I had to repair it with glue and greenstuff.

So i thought it easier to see if I couldn't find something that was 4mm off the bat.

 

[Wookiepelt]

So i thought it easier to see if I couldn't find something that was 4mm off the bat.

Maybe something like a small Dremel drill, ideally with the flexible shaft attachment?

 

[Dusty's Corner]

Maybe this'll help
http://www.heresy-online.net/forums/showthread.php?t=126034

 

[Loki1416]

I'm currently using the dremel with shaft attachment that Wookiepelt linked. I find that if I hand drill the pilot hole and then switch to the dremel with the flexible shaft for the larger bit, works wonders. I've got a dremel that I can adjust the RPM's on and have found that a lower RPM works the best. The higher RPM's wants to eat through the model (put a bit straight through an arm and into my finger, hurts like a bitch and then you have to pull the still spinning drill bit out!).