View Full Version : Bow drill - Bearing block
Stu Mac990
30-06-2004, 11:25
Me and my Mate have been wondering what would make a good hardwearing, longlasting bearing block for the Bow drill, that we would always have in our kit to take with us.
He thought Ebony would be good to use but expencive. I've heard bone is good, but what bone would be best?
Any thoughts on what else would be good?
Buckshot
30-06-2004, 11:32
A stone works well.
Flint with a natural hollow is good. Then, if all else fails, you've got the ability to create sparks - as long as you have some steel to go with it :wink:
Cheers
Mark
MartiniDave
30-06-2004, 11:33
I think I've seen a fire drill bearing feature on the micarta handle of some custom bushcrafty knives - I think Allen Blade may have been the maker. I expect Hoodoo or Schwert will know.
Dave
Here are a few:
Soapstone, hardwood (no need for it to be too exotic), micarta, flint ...
a piece of box wood would be good i'd have thought. seem to recall its one of the few woods that don't float.
A bone insert in wood works very well. Its hard wearing but fairly friction free.
I'm trying t get a bit of this greenheart wood for this, the hardest of all hardwoods I've been told
A bone insert in wood works very well. Its hard wearing but fairly friction free.
Did you mean an insert in the bearing block or in the top of the drill? ummm.... I've used a drwing pin in the top of the spindle/drill to reduce friction against the bearing block but I'd never thought of making a bone one for it.... I may just have to try ;-)
:-)
Ed
A bone insert in wood works very well. Its hard wearing but fairly friction free.
Did you mean an insert in the bearing block or in the top of the drill? ummm.... I've used a drwing pin in the top of the spindle/drill to reduce friction against the bearing block but I'd never thought of making a bone one for it.... I may just have to try ;-)
:-)
Ed
Ok, let me elucidate...
The bone socket is inserted into the bearing block. You use a normal spindle. the only troubel is that the bone does ridge the spindle, being harder, so you have to shave the spindle occasionaly.
I got this trick from Gary (sorry if that was your little secret mate) :oops: . He put a piece of sheeps knee joint(?) into the bearing block. He has a FANTASTIC fire-bow set. :ekt:
No worries Jak - at least you never told them about the magic symbols that bring fire!
And yes a bone socket with a natural depression works well and is pretty much self lubricating. Mine is a Deer's knee joint which I got from a road kill.
Native americans are reported to have used soap stone sockets in there sets - I have some soap stone but as yet havent had time to try this out so I cant say how well it works.
As for ridges on the spindle you will find this happens no matter what material you use.
Best natural material for a bearing block would be any hard wood - beech being a favourite - but you will never find a natural bearing block that will last forever.
Yeah, but i would imagine that the bone, whilst reducing the friction on the spindle would collar it faster?
I have a cool bit of seasoned Elm as a bearing block, but if you like beachcombing keep your eyes peeled for a nice polished pebble with a depression in it and Robert's your aunties husband :-D
To be honest its so long since I used anything else I cant remember, but common sense dicatates that wood on wood would generally create a even (ish) wear - will wood on bone would wear the wood more than the bone.
However as you saw Jak, a hard wood spindle (that one was BEECH) bearing into a soft wood hearth (Alder) works better than two woods of the same hardness and if the spindle is hard wood that will offer some resiliance too.
At the end of the day its courses for horses I guess.
So that's what my scribbled notes said! Beech and Alder!!
Must have been the smoke :cry:
Didnt think that was a normal cigerette!
Excuse me! Apart from a couple of menthols on holiday last year I've not smoked for ohmegod 19 years!!!!
Cheeky :***: :wink:
ChrisKavanaugh
30-06-2004, 18:24
http://www.wildernesssurvival/rangerknife.htm This is one survival knife with a divot for the bowdrill. In european archaeology there is the "baton de commandant" a decorated bone with open socket. For years it was thought to be a shaman's magic wand. Today it is recognised as a shaft straightener. Another goofy theory has them part of a prehistoric bridle.
That link didnt work Chris but never mind I think I have seen the knife before.
The bone THING also reminds me of a tool which can be used in bow drill fire lighting which makes the whole operation so much easier. Its a secret weapon we us on courses when a student really is struggling to suceseed and I suspect the bone wand may have been used in ceremonial fire lighting rituals where sucess was needed to be garunteed every time.
interesting thought.
C_Claycomb
30-06-2004, 20:31
Lignum Vitae is the hardest wood, or so I thought, it is also very waxy/oily. The wood has been used for self lubing bearings in clocks and stuff. I wouldn't use ebony since it is a "dry" wood, no natural waxiness. I haven't tried box, but having carved it I reckon it would be at least as good as ebony, possibly better, and a lot easier to get.
A bit of fat goes a long way in a hard wood block. I have used a bit of ash from my fire pile with a bit of lard worked into the socket. It doesn't need extra lard every time, it sort of gets slick.
Carcajou Garou
01-07-2004, 04:03
I use the cast off section of a moose antler, I sawed off the antler approx. 2" from the base and drilled a 9/16" shallow hole into the sawed face, added grease to the bottom of the newly drilled socket. Voila an extremly hard wearing socket that fit in the palm of my hand.
just a thought
Just a thought, but has anyone been to the beach recently, there are plenty of shells (like limpett) which are quite hard and very smooth internally, in theory you could epoxy (or use a natural glue) one of these into your bearing block.
Because it is smooth it reduces the friction on the drill and anything that you wish to use (an oily leaf like holly) can be used as a lubricant. There is the bonus that it is not as heavy as carrying a pebble in your kit. :-D
A bone insert in wood works very well. Its hard wearing but fairly friction free.
Did you mean an insert in the bearing block or in the top of the drill? ummm.... I've used a drwing pin in the top of the spindle/drill to reduce friction against the bearing block but I'd never thought of making a bone one for it.... I may just have to try ;-)
:-)
Ed
I know it's not exactly what you were thinking of but how about this,
http://www.primitiveways.com/images/pt-bowspindraw.jpeg
courtesy of Primitive Ways (http://www.primitiveways.com/pt-bowspinext.html) - the site explains it's use.
and if you want to try something new with a bow drill check out their Smallest Bow Drill Fire-by-Friction Set (http://www.primitiveways.com/pt-small-fire.html)
Shells work well. The instructor at the course I did a long time ago used that, with just a little piece of leather between the shell and his hand, in case the drill burnt through the shell.
I was told the person doing a demonstration at the local Celtic festival also used a shell (it was maybe the same person though).
I tried it, it's stable, holds the drill well, it's easy to hold...I think it's a good solution. You don't get shells over here though :-P
I can't remember the other things he suggested though.
(hmmm, now that I thought a bit, is the bearing block the handblock or something between the drill and the handblock? Anyway, you don't need anything other than a shell, it works well alone)
Douglas the Bearing block is just a block of anything that sits on top of the drill. :-)
The reason that I said about epoxying the shell into the wood of a bearing block is more comfort than anything else (something easy to grip), although the leather is a very good idea. Was the leather boiled and dried or just like a chamois cloth / still supple :?:
Interesting idea the shell thing but I think it would be too brittle - having seen the heat generated at the both ends I honestly feel it wouldn't last long.
But proof is in the doing so I guess I will go try it and report back!.
Was the leather boiled and dried or just like a chamois cloth / still supple :?:
It was still supple.
Thanks Douglas, I will have to give a go.
Interesting idea the shell thing but I think it would be too brittle - having seen the heat generated at the both ends I honestly feel it wouldn't last long.
But proof is in the doing so I guess I will go try it and report back!.
I tried a limpet shell set in a wooden block a while back but did find it to be pretty brittle under pressure. A larger, thicker sea-shell should work well though. I'll keep experimenting!
How about a whelk shell? Has a nicely polished hole pre-made and fits the hand nicely?And they're tough buggers! (and I don't just mean the flesh...)
Around Kent I used to find load of large whelk shells, up to 3 inches, also in Dorset.
Alternatively, just go to your local fishmongers...
Well the Limpett shell worked fine on the Isla Journeyman, as Jason and Gary could testify, all you have to do is find a shell which is adeqaute. :-)
I use the same as Carcajou - only from a shed red deer antler. Fits my hand nicely.
George
Just a thought and it has probably been said before but...
If we follow this discussion on for developing and refining such a simple and elegant solution through to its natural conclusion would we not end up with a fire flash or lighter prehaps? :?:
I would say that it is the knowledge and ability to improvise the Bow-Drill, so that it may be employed when other modern/manufactured fire lighting methods are not available, that is important.
gurushaun
17-08-2004, 16:41
The ability to improvise and use the drill set is important, but so is the process of refining the components, using what you have to hand.
Cheers
Shaun
What about a shaft bearing from a gearbox?
In a week I go to our mountain cabin in Austria. While there, I usually collect a bunch of Alpine cherry wood. That is a VERY hard wood and gives me a nice pile of bearing blocks that will get me through the year. Makes great handles for knives too.
-Emile
mr dazzler
05-09-2004, 22:07
Bearing (oops sorry no pun intended!) in mind that the finest german woodwork planes have hornbeam soles to resist wear, could be that wood may be a suitable choice for a bearing block.
Mr D :wink:
Just another thought.
Is it a rumour or is it true the soviets had some sort of super-hard fossilised wood that was hard enough to build tanks? :?:
I tell you what works really well for me is a pebble that fits well in your hand with a little depressionin the middle ( i got my one on the beach) i use mine all the time to demonstrate the bow drill.
A soapstone insert in a block of wood for your bearing block works a treat.
I tell you what works really well for me is a pebble that fits well in your hand with a little depressionin the middle ( i got my one on the beach) i use mine all the time to demonstrate the bow drill.
Pickd up a couple from the beach today and they work really well.... I've been looking for a good shaped stone for ages .... then loads come along at once :biggthump
I also picked up a few small limpit shells which I'm going to try as insets in a wooden bearing block...
Ed
Paganwolf
08-09-2004, 13:01
I found a flattish mettle limpet shell with stella atois written on it that worked well :rolmao: amazing how many of those little critters you find in my garden just after a BBQ, must bring em out :?: :trink26: :rolmao:
So Gary whats the secret weapon.
"The bone THING also reminds me of a tool which can be used in bow drill fire lighting which makes the whole operation so much easier. Its a secret weapon we us on courses when a student really is struggling to suceseed and I suspect the bone wand may have been used in ceremonial fire lighting rituals where sucess was needed to be garunteed every time."
R-Bowskill
18-09-2004, 12:29
I do it the other way round, I've glued a small agate pebble onto the bearing end of the drill and that has improved performance, It does now look like something used by merlin though, which might be an asset for ceremonial use.
spiritofold
08-10-2004, 09:42
Those little paste jars are good,very little friction....
I do it the other way round, I've glued a small agate pebble onto the bearing end of the drill and that has improved performance, It does now look like something used by merlin though, which might be an asset for ceremonial use.
how does that work.. doesnt it rotate with the drill in your hand and get hot?
Jeff Wagner
08-10-2004, 19:44
The best wood I can think of is lignum vitae. This wood has a natural, waxy characteristic and self-lubricating quality. It would make a splendid socket for a bow drill. As trivia point, the clock works of worlds first marine chronometer which gave birth to modern navigation were made of lignum vitae.
how does that work.. doesnt it rotate with the drill in your hand and get hot?
As long as the pebble is smooth and has enough surface area it will reduce friction and allow you to place enough down force via the bearing block. With the surface area bit that should be a case that it will not then drill into the bearing block itself or if it does, it will be at a reduced rate :wink:
I've used all of the following, so I thought I'd pass comment on each in turn:
Bone socket (sheep 'shoulder'?) - Worked well, but quite bulky to carry around, and needed a lot of lubrication to prevent excessive wear to the spindle
River-washed Pebble - worked in the same way as the bone socket, but slightly rougher, so more lubrication needed.
Large Limpet Shell: http://members.lycos.co.uk/Mollusks/images/weichtiere/schnecken/limpet.jpg
Worked very well as was a very smooth surface and therefore needed very little lubrication - however, being very thin it can tend to get hot, so a piece of leaf/leather held on top to prevent hand being burned is useful! These shells also have a tendency to break after repeated use, as the heat from the process weakens the shell structure. However, they are in abundant supply on all UK beaches!
Beer-bottle cap and wood (copied idea from here: Aussie FireBow (http://www.uq.net.au/~zzdlittl/ aussiefirebow.html) )
Made by getting a small piece of wood, and putting a beer bottle sharp-edge down onto the wood and tapping slightly until it beds into the wood. The spindle is then sharpened to a point, and the pressure of this on the cap makes it indent and forms a socket. This worked very well once I got used to it, but it took a lot of practice to stop it flying out of the socket, and I just felt a bit wrong using a bit of modern waste in a primitive fire-starting kit!
(There are obvious other modern objects that can be used for bow drills, and I have used and seen used an eclectic range including shot-glasses, film canisters and the bottoms of drink cans!)
Split green branch - Made by simply cutting a small green branch from a tree (no more than say 2 inches in diameter) and splitting it vertically to provide two pieces, each with a flat side and curved side. This requires a bit of crafting to make a suitable notch for the spindle, and then also requires reasonable amounts of lubrication (top tip - remember that ear wax and the grease on the sides of your nose is a really effective lubricant!), but has the advantages of always being available, can be made with nothing more than a knife. The greenness of the wood also naturally suppresses any smoking/smouldering at that end, (although it is obviously not as smooth and frivction-free as some of the above methods). This is still the method I tend to favour, as I find the act of sitting down and preparing a hand-hold for a fire kit makes the kit itself work better for me - after all, a lot of fire-starting is to do with mental attitude as well as technique, and the construction is a big part for me! However, for my very small pocket kit, I use a limpet shell, purely for size and space reasons!
Hope this helps someone - if anyone else knows of any other obvious hand-holds, please let us know!