Drilling Blanks

[gbuckham]

Guys,

Looking for an accurate method of drill pen blanks.

Considering a bench mounted pillar drill but notice that those within budget - about £100 - only have a spindle depth of 50 mm. I take it that's how far the drill will movedown when the lever is pulled?

As cut pen blanks are slightly larger than 50 mm, do you have to move the table up to complete the hole? Seems that accuragy would be lost?

Any assistance appeciated.

Gary

 

[stevebuk]

hi gary
i used a pillar drill , and still do on odd occasions, but mostly i use a drillchuck mounted in the tailstock with drill bit in and blank mounted via a chuck in the headstock and bore through.
Mostly very accurate, but depending on what you are cutting ( ie: segmented blank) it can still vear off.
Make sure you clear the debris often by only drilling 1/8th inch then clearing it, oh and a sharp bit is standard.. :lol:
HTH

 

[duncanh]

I drill on the lathe like Steve.
With the blank held in a chuck I square off the end and put a dimple in the centre to help align the bit.
I've found Black and Decker bullet point bits the best but my local B&Q no longer stocks them so I had to buy from Toolbank

I manage to accurately drill piano keys this way and they only have around 2mm clearance, so no margin for error. I get the occasional failure but it's usually when I'm impatient and try to drill too quickly.

 

[loftyhermes]

I used to use pillar drill with a 50mm travel .(a £30 special from netto ages ago) and when drilling blanks I slip a piece of 19mm. mdf under to finish, but now I drill them on the lathe the opposite way round to stevebuk, with the drill chuck mounted on the headstock

 

[THOMASB]

I have the same problem, is there a way to hold the blank in the chuck without paying out for Long Nose Jaws (£50-£60!!)?
:roll:
Thomasb (John really)

 

[CHJ]

Most 4 jaw scroll chucks will hold a small square blank in the mouth of the carrier jaws, some auxiliary jaws do however prevent the carriers closing sufficiently and may have to be removed.

I prefer to drill on a pillar drill, if you have one with a limited travel, dependant upon your method of holding the blank you can either, as has been mentioned place a packer under the blank holder to complete the drilling, or lower the drill in the chuck 4-5mm to extend its reach in the partially drilled hole.

No problems should be encountered with accuracy with either method as the length of the bored hole will hold the alignment of the drill.

If drilling on the lathe make sure you do a test drilling before using an expensive blank, not all tailstocks-headstocks align with the best of accuracies.

 

[oddsocks]

I have the same problem, is there a way to hold the blank in the chuck without paying out for Long Nose Jaws (£50-£60!!)?
:roll:
Thomasb (John really)

John , I now drill my pen blanks using a SIP pillar drill - bought specifically because it had an 80mm travel (from memory was a 'last years model' so about £175).

Before that I used a home made scrap jam chuck screwed onto a faceplate. I drilled the scrap with a suitable drill (held in tailstock chuck) and then squared up the hole to suit the standard size pen blank. This worked very well providing the blank was a tight fit (if not masking tape etc was used) - you could taper the squared hole to give some scope for different sizes. I have seen in catalogues similar morse taper holders for lace bobbins but none for the bigger size needed for pen blanks (hence I did my own).

HTH

Dave

 

[duncanh]

Depending on the size of your blanks you may be able to hold them in a jacobs/drill chuck - that's what I do when drilling piano keys for pen blanks. You'll need a largish one, of course, and if your blank doesn't fit you could always turn down one end until it does.

 

[John. B]

Hello Gary
I make tall Salt & Pepper mills and need to drill acurate holes
10" to 12" long.
If you look in 'Jigs & Tips' under the post 'Long hole boring jig' It
shows the jig I made to do just that. It does need a floor standing pilar drill with a slow speed for the auger.
You drill to the full length of the drill, wind up the table and continue drilling clearing frequently. The way augers are made (with wide lands)
keeps it on the straight and narrow, so to speak.
The augers I use are from Screwfix, they are, Erbauer long auger
bit set. 10,13,16,19,22, and 25mm X 400mm long in a case for £14.95
Hope that helps
John.B