Boring all the way through timber blanks - what chuck/jaw combo?

[bpbuilder]

I have some blanks of timber ranging from 100mm to 300mm in length and from 35mm to 55mm in thickness. I need to drill holes up to 21mm right through the entire length of them (using gun drills). The problem is that the blanks are essentially cut to length so I haven't got any room to 'play'. Basically it's exotic and too precious to waste...

I have a VM100 but its 'through bore' is about 21mm so it's not an option to use this chuck if the blanks are butted right up against it. The VM120/150 has a bigger bore around 30mm as I understand. So this might be a better option.

What I'm struggling with is chuck jaws for this purpose. Most of them would essentially close off the bore in the chuck (or at least part of it) so I wouldn't be able to drill right through the blanks. I've considered pin jaws and possibly long nose jaws both used in compression mode and possibly I could leave some space behind the long nose jaws for the drill to exit. I'd be using these in conjunction with a steady rest. Not sure how safe either of these options would be. Plastic jaws might be an option but would probably prefer something more permanent.

Short of that maybe the only way is retrofitting a metal lathe chuck to my wood lathe which I think may do the trick with an appropriate large through hole and naturally having the external jaws that don't block the through bore off.

Anyone done this kind of thing before and willing to offer any suggestions on the best route to take?

[Optimark]

Seeing that you already have the VM100, perhaps a set of Shark Jaws may work well. I don't have a set, but upon reading the Vicmark VM100 owner's manual, it would seem that these jaws are probably best suited as they give great grip, in either compressed or expanded mode.

Mick.

[Mobyturns]

Look at the V00647 Long Nose or V00654 Shark 55mm jaws and use a spacer between the blank and chuck body.

[RoyG]

Also consider gluing wood blocks on each end of the blanks to provide you some extra length so you don't loose any lenth due to tearout when you bore through..

RoyG

[Nubsnstubs]

Have you thought about using the jam chuck set up the Russians and Japanese use for making their nested dolls? Just tap the blank into it, center it and drill the hole. I know it sounds simple, but I'm sure there is a learning curve............ Jerry (in Tucson)

[brendan stemp]

I would use a combination of what has been suggested already. Shark jaws will give you the extra length in the jaws and I would also use a scrap block approx the same size (in section not length) as your good blank (perhaps a little smaller so the jaws grip the good wood and not the blank). The scrap shouldn't need to be glued to the good wood; the pressure of drilling should keep the hard up against each other. The scrap would only need to be 10mm long and would enable you to drill right through without any danger of drilling into the chuck. I used to do this type of drilling regularly and have a You Tube video showing the process I used which may be of some help. Gun drills are not needed.

[bpbuilder]

Thanks Brendan, yes it did help thanks. Would like to set how you drilled the tone holes in the recorder too! :D