|
|
|
Large wood / steel hs drill bit with small shank? |
|---|
| message from T i m on 15 May 2004 |
Hi folks,
I'm trying to make a special drill for drilling out the stump of a 9"
sq wooden gate post but want to leave the surrounding concrete intact.
The idea is to drill enough 'joined' holes across it to be able to
pull the two chunks out using screw eyes (chain and coachbolt) on some
scaffold pipe, car jack etc (Ideas from this list and thanks <g>)
So, I bought a cheap (1 pound. market) SDS 14mm drill that I can use
for the SDS part, drill / mig that into some tube (or bar counter
bored on the lathe) and then connected to a large (25mm) wood / steel
drill bit? (cheap from a boot sale?).
But, because it would be difficult to hold the business end of a drill
in the lathe to turn the shank down (or counter bore) for my extension
tube / rod system I think I need to find something big but with a
small shank ready to go ..?
I nearly bought a cheap (39 quid?) set of such drills recently, going
from about 12mm up to 30mm or so but all with 12mm plain shanks but I
wouldn't want to risk ruining such a bit (and the set) on this job?
So, any ideas please? (links prices etc?)
All the best ..
T i m
(Someone kindly suggested 'sharpening' a masonry bit but looking at
it's design I'm not sure it would work very well through 4.5m (9 holes
x .5m deep) of 'good' wood?)
|
| MBQ replied to T i m on 18 May 2004 |
Can a core drill be used in wood?
Or a set of hole cutters. Go as deep as you can then chisel out the
plug and do the same again?
MBQ
|
| BigWallop replied to T i m on 15 May 2004 |
Have you thought about sharpening the end of a piece of threaded rod ? The rod comes
in all sizes and sharpening the end into a point and cutting a couple of straight
slots for few inches up the length would give you a cutting point that could be
drilled in and pulled out a few inches at a time.
I think I saw some on the Screwfix website that is 1mtr long X M10 and was 94p a
length. B&Q also stock it at roughly the same price or not much more.
|
| T i m replied to BigWallop on 15 May 2004 |
Hmm, that's a new idea, like a very long starter 'tap' ;-)
I do have various lengths / diameters of 'studding' in the workshop
... ;-) I'm not sure how well it would 'clear' though but I can see
the idea (I was probably going to have Henry working in there as well)
might work. I would imagine this would be very good for breaking up
nearly rotten timber but if this one is like the last one I did it
will be clean solid timber about 1" under the rotten end?
As you say .. pretty cheap experiment in any case ..?
All the best ..
T i m
|
| T i m replied to T i m on 16 May 2004 |
Hi all,
It's funny what comes to you in your sleep ;-)
I was trying to think how I could put a small(er) shank on a large hs
twist drill for my project (assuming I can't buy one ready to go) and
how to hold it in the lathe ..
Just thought .. if I hold the plain shank in the 3 jaw, turn a section
down from the chuck towards the tip of the drill then saw the section
that was in the chuck off afterwards? The only way this wouldn't work
is if it's got a morse taper rather than a parallel shank?
With that attached to my SDS fitting via a .5m length of tube / bar
(bored) and the ends tacked in with the MIG I should have a high
speed, reasonably tough, true, re-sharpenable post stub drill ;-)
Now, when's the nearest boot sale for a large, cheap drill bit .. ;-)
All the best ..
T i m
|
| Ian Stirling replied to T i m on 15 May 2004 |
Why not?
Looking at one, if you take a fair bit off the top, to leave a
90 degree cutting edge, with some relief, then it will cut fine,
though perhaps not as fast as a proper bit.
Cutting away a large portion of the bit support that the carbide is
soldered into to enhance chip removal would be a good idea.
Alternatively, a simple auger worked very well for this sort of thing.
If I could have welded it on a long shaft, it'd have been ideal.
(it was around 1")
|
| T i m replied to Ian Stirling on 15 May 2004 |
That was my thought Ian .. ;-(
I *do* have a 1m long 25mm SDS bit but I didn't really want to muller
it just for this job when for similar money I could (possibly) make
something more suitable?
Are you talking 'hand brace' here Ian? Well that *is* a thought, would
be easy to extend and would be quiet in use but I don't fancy plugging
through 4.5m of even softish tannalised timber by hand if I can help
it?
Maybe I'll get one of those wood chewing things for the angle grinder,
lock it on, throw it into the hole and run away! ;-)
All the best ..
T i m
|
| Ian Stirling replied to T i m on 15 May 2004 |
Maybe.
I too have a 1m long 25mm SDS bit, but probably don't treasure it as much,
as it only cost me ten quid.
Actually, not.
Mains 600W drill, worked fine.
If it was longer, it'd have been a lot easier, as I ran into problems
with it hitting the sides of the hole.
An adaptor for the much slower turning more rugged SDS drill would be
just about ideal.
You do of course have to beware of hitting the concrete at an oblique angle.
Hitting a flat end, or hitting a side at a very shallow angle doesn't do
too much damage.
Those are fun.
I needed to abrade off the gel-coat from a fiberglass pond, and it
made the job almost trivial, providing a really nice key all over.
(the existing gel-coat was flaking)
At least a hundred times faster than a wire brush in a drill.
|
| T i m replied to Ian Stirling on 15 May 2004 |
My set of 3 were only 15 quid but I visualise a more 'suitable' home
made tool only costing a fiver (my time is free) and would probably do
a better / quicker job?
So one of the spiral wood augers with the tip like a woodscrew and the
vertical cutting blades either side of the lifting edges? On an
electric drill? Surely if that 'bit' it would attempt to drill down at
a fair rate, even with a drill set on 'low / slow'?
Well that was the thought re the SDS .. slower / torquier, HS bit
(tough / designed for speed and easy to sharpen) and l o n g
extension so I could possibly work standing up and save my old knees /
back ?
Sure .
I bet! I have used those angle grinder wirse brushes with the
'bristles' made of what looks like 3 twists of coathanger ... nasy bit
of kit but pretty effective on rust ;-) You just don't want it
catching your sweatshirt or finding the hole in your jeans .. ;-(
All the best ..
T i m
|
| Ian Stirling replied to T i m on 15 May 2004 |
Ebay, set of three?
It does.
It is controllable though.
<snip>
Combined with a slow, high torque SDS drill, I think it'd be a good match.
I think I would avoid working standing up if I could.
Poorer control.
Get a nice thick kneeling mat.
Wire brushes at high speed are NASTY.
Somehow the sharp end of any falling out bristles lands in exposed flesh
at high speed.
The carbide grit disks are much kinder and gentler, though not
a good idea on metal.
|
| T i m replied to Ian Stirling on 15 May 2004 |
I think mine were the same as the eBay ones but were from the Friday
market at the top of the road so no carrage ;-)
Fair enough ..
I only have one (well two actually) of the cheapo SDS's (1 from Argos
19.95, the other from Makro, 14.99 + Vat) and am not quite sure how
slow slow is (or even that it has more than one speed?)
And get a smack in the gob when it jams ;-) (I get your direction
though)
Of even non exposed flesh .. I found they go straight through a
sweatshirt sleeve!
All the best ..
T i m
|
| donny replied to T i m on 15 May 2004 |
Call me a pyro but I'd try burning it out.
Donny.
"T i m" <kitcar@ntlworld.com> wrote in message
news:4e2da0p4ug3ae8lglue5eohaa81v4do5q1@4ax.com...
|
| T i m replied to donny on 15 May 2004 |
Hi Donny the 'Pyro' ;-)
This was put forward as an option to a similar question I asked
recently (same problem, different 'angle'), but:
It's right on the public footpath
It's quite deep
I don't know how it would 'breathe' (so probably go out without blower
asistance). Maybe if I got some sort of thermal lance fitting for my
BOC Portapak I could take the bottles back empty!) ;-)
It's probably 'damp' ;-(
I think I tried it last time and it was very slow ..? ;-(
I don't want to crack the surrounding concrete (I want to refit a
smaller steel post)
I may well have missed a technique on any of the above (I've thought
of Semtex) though?
All the best ..
T i m
|
| Grimly Curmudgeon replied to T i m on 17 May 2004 |
something like:
Bugger.
In view of it being on the public footpath, it probably rules this out,
but thermite might be just the thing.
|
| Tony Williams replied to T i m on 16 May 2004 |
Bizarre sideways thought.....
Could the stump be pumped out hydraulically,
or at least freed enough for a straight lift?
Drill one hole down the centre, about an inch dia,
and right through the bottom. Fill the hole with
water until it will take no more. 1 inch steel
bar as the piston, and a sledgehammer.
|
| T i m replied to Tony Williams on 16 May 2004 |
Hi Tony,
Sideways yes, bizarre, possibly not!
I was considering a 'straight lift' one I'd given some of the wood
somewhere to go. (ie, create a 'gap' across the middle by chain
drilling. collapse one side onto the other (creating some 'space),
extract chunks using screw eye (coach bolt) on long lever (scaffold
pole) over hole?)
I like it! ..
Only reservations (ever the pessimist)
I can't remember how 'sound' the bottom of the hole is and therefore
it might
1) blow the 'bottom' of the hole *if* it is intact.
2) Simply force the water down / sideways into the surrounding ground.
I assume of the piston 'stroke' can be made long enough (depending on
how much energy you can apply to the 'piston') the effort would still
be applied to the bottom of the post by a huge ratio even with some
'losses?
Post = 9" x 9" = 81 sq inches. Assume piston 1 sq" = 80:1 mechanical
advantage. If this was backed up with some vertical 'pre-load'
(scaffold pole tension lever from above ..) Hmmmm ;-)
The other neg might be the post being soaked my swell up and jam
itself back in the hole?
Brilliant idea though!
All the best ..
T i m
|
| Tony Williams replied to T i m on 16 May 2004 |
The other big neg is that water will squirt
everywhere. So wear your bikini. :-)
|
| T i m replied to Tony Williams on 16 May 2004 |
Well, I suppose that depends on how well the post is stuck in the hole
and how well the piston fits it's cylinder ..
So wear your bikini. :-)
That was a 'given' Tony (and not a problem in the sun like today) ;-)
All the best ..
T i m
ps Have you done this yourself (hydraulic post removal not bikini
wearing) ?
|
| Grimly Curmudgeon replied to T i m on 16 May 2004 |
something like:
I've used that technique to remove flywheel spigot bushes; I don't see
it working on the stump, though.
|
| Cicero replied to T i m on 16 May 2004 |
The 'hydraulic' method is a fairly standard way of extracting metal bushes
from car engines / gearboxes but I think it might not work with your gate
post because the concrete will have moulded itself to the shape of the
wooden post. Still it should be fun trying but don't stand too close when
you hit the 'piston' with your sledge hammer as it's likely to shoot back
out of the hole like a rocket.
Cic.
|
| T i m replied to Cicero on 16 May 2004 |
I was thinking that. I would also thinking that I should leave the top
of the hole clar to try to let the stump dry out and shrink a bit?
Still it should be fun trying but don't stand too close when
Ooops ;-)
T i m
|
| Tony Williams replied to T i m on 17 May 2004 |
[snip]
No. The thought was from an experience of lifting
two large gateposts out of Herefordshire clay,
using a car jack and levers. The hydraulic suction
was so large that it nearly defeated the job. The
saving grace in clay is that the post can be rocked
to break the seal.
|
| Pete C replied to Tony Williams on 16 May 2004 |
Or drill a 15mm hole, glue a length of 15mm copper pipe in and attach
it to a hosepipe?
cheers,
Pete.
|
| T i m replied to Pete C on 16 May 2004 |
Or my pressure washer?
T i m
|
| Pete C replied to T i m on 17 May 2004 |
Maybe! Depends on how much water might leak out, the flow rates on
pressure washers aren't always that great.
If anything a hole through to the bottom of the post would help break
any suction that develops under the post when levering out, as
mentioned by other posters.
cheers,
Pete.
|
| T i m replied to Pete C on 19 May 2004 |
True .. mines a fairly old Kew Hobby .. seems quite punchy?
Good point .. ;-)
All the best ..
Ti m
|
| MBQ replied to T i m on 18 May 2004 |
Another thought. How about a "scary sharp" SDS chisel bit?
MBQ
|
| T i m replied to MBQ on 19 May 2004 |
Hmmm ,, where's the angle grinder .. ;-)
I was 'hoping' for something less energetic. ;-)
The 'problem' with this job is that for a large part of it I'll be
working in a 9" square concrete hole and hence the need to try to get
away from the ground a bit (excuse the pun).
Off to B&Q to check out some electric drill speed augers ..
T i m
|
| Cicero replied to T i m on 15 May 2004 |
Have you considered a wood auger bit? They come in quite large sizes but
even the large sizes have a small shank (about 9mm).
The expensive drill set you describe is probably a set of blacksmith's
drills and they're very expensive.
Cic.
|
| Dave Liquorice replied to Cicero on 15 May 2004 |
As the OP wants joined holes I think an auger bit is the only sensible
approach. Any "ordinary" drill is just going to wander into the
adjacent hole very quickly. Even so I doubt an auger bit will keep
true for 1/2 a meter...
As to the initial problem, interesting. I think I'd end up with a
brute force and ignorance approach of some sort, involving lump
hammers and long sharpened bits of steel bar to split and break up the
timber. Rather than trying to drill accurate 18" deep holes...
|
| Ian Stirling replied to Dave Liquorice on 15 May 2004 |
It won't.
If you can get a long enough drill, it reduces to more or less making
it swiss cheese, then hitting it with a sledgehammer/drift, and picking
bits out.
|
| T i m replied to Dave Liquorice on 15 May 2004 |
The 'idea' here Dave would to drill pilot holes (say 12mm) with a long
extension so that I can get the fairly upright and at say 60mm
centres. Once they start to go there shouldn't be much to send them
astray. If I then follow up with the 25mm 'superdrill' that should
follow the the pilot holes and then some rabid diagonal drilling after
that to eat away the 'bridges' ?
Even so I doubt an auger bit will keep
I fell a hand cranked bit is less 'easy' to keep vertical than an
electric one? I could ecen set one of those caravan 2 direction levels
on the back of my SDS drill to keep it steady all the way down. If
thay can join two tunnels half was across the channel, *I* should be
able to keep a .5 m run straight (ish) shouldn't I?
I used that approach the last time I did the same to the other post
Dave. Just didn't fancy spending any more time than necessary laying
on the pavement with my hand down a hole up to my shoulder like some
old gold prospector ;-)
The other 'problem' here is *I* set these posts originally (some 26
years ago) and I remember exactly deep they are and how much concrete
is around them. (*my* fences have all survived the same storms that
sent everyone elses 6' panels flying down the road .. just the rot
thing that has let me down ..)
My *dream* is to walk out there with my large tool (titter <g>) and
have the old post out cleany and in double quick time. To that end I
don't mind spending time and (some) money making (if needed) a tool
(or tools) to help me do so?
All the best
T i m
|
| Dave Liquorice replied to T i m on 15 May 2004 |
I doubt it but your plan with pilot holes will certainly help.
|
| T i m replied to Cicero on 15 May 2004 |
Yes I have .. but I was hoping for something fast and these need
cranking with a hand brace don't they Cic?
They might if been .. as I said they were about 39 quid (for a set of
maybe 7?) and I was going to get them for getting the bulk of material
out when boring something on the lathe (press tools etc)?
All the best ..
T i m
|
| Cicero replied to T i m on 16 May 2004 |
Wood augers can be used in power drills so you don't need to worry too much
about the hard labour aspect!
Another possibility would be to use a flat wood bit for which you can buy a
300mm extension bar. Look at www.screwfix.co.uk Look in drill bits / wood
drills - item no. 16769. This item is cheap and and together with the length
of a flat bit would probably go all the way for you - provided that you
don't lose the bit somewhere in the hole!
Cic.
|
| T i m replied to Cicero on 16 May 2004 |
Really? I would have thought it would have done it no good?
I was more worried of it snatching as it broke through between the
holes?
All the best ..
T i m
|
| Ian Stirling replied to T i m on 16 May 2004 |
Seems to work just fine.
It does, badly.
An auger is much, much more controllable, even when cutting the
wood into swiss-cheese.
|
| T i m replied to Ian Stirling on 16 May 2004 |
Just had a look at augers on Screwfix (as Cic suggested) and they seem
to have different (chuck) ends compared with my Dad's selection. His
have a sort of square 'bulged' bit where they go in the brace (hence
why I was unsure re the electric drill thing ..)
Fair point .. I'll try one .. ;-)
Cheers
T i m
|
| Cicero replied to T i m on 16 May 2004 |
Screwfix sell some short augers. I've used them in my bench drill for
several years without mishap.
Cic.
|
|
