Brass Fire Piston MkII

[shadow57]

Hello all

When I posted a recent article about making a fire piston from brass, I had a few requests to trade something for a ready made piston. Off I went to make some more and I thought there must be a better or faster way of making these things. Most people dont have access to a lathe,but I know I have overcome this problem.

I got some standard size bar 6mm and 12mm. Using a 6 mm drill in a pillar drill it is possible to complete the task . Drawing attached.

Now most of you wont believe this when I say it takes 30 minutes to make one piston, but it does.

I will add a photo soon of a completed piston.

Hope this helps non lathe owners.

 

[Ogri the trog]

Shadow57,
Hi buddy and thanx for the info, one question though -
How do you get a good enough internal surface in the bore? Do you use a special type of drill bit or is a standard drill suitable?

Ogri the trog

 

[Big John]

ditto - looks great. Do you have to smooth the bore? I take it that's a rubber o ring at the end of the piston? I also assume that the bottom of the bore is rounded from the end of the drill and not flat as you've drawn it - or did you use a flat ended drill bit, obviously a flat bottomed bore would give better compression, but is it necessary?

Sorry about all the questions, but this looks like a great little project!

Thanks,

 

[jdlenton]

I'm also interested in how you finish the bore I recon the O ring won’t last very long with just a drilled surface to the bore but I looks like a good little project get some photos up we all want to see

 

[shadow57]

Hello again,,

The bore was drilled using a normal 6mm drill...There is no need to smooth the bore as it already smooth after drilling

The O Ring groove is done with a file ....................and the O Ring is a slice cut of a length of rubber tubing that u can get from a fishing tackle shop.

Word of warning...the char cloth needs to be dry.....sometimes bits break off and clog up the chamber....which is very small and it will not work..

The piston does work...but it takes practice..

Included a photo of some pistons that were used today at school....Teechas amazed when it works...

You could get better results if you use a longer chamber and piston but you need an extra long drill..

Any problems give me a shout...John

If anyone wants to swap something for one piston...Im up for that..

 

[jdlenton]

They look very practical nice one

Right I'm off to get some brass out of the store and get my self no the lathe fire piston here i come

 

[shadow57]

Here is a contact for brass bar

http://stores.ebay.co.uk/Ringwood-Precision-Engineering_BRASS_W0QQcolZ4QQdirZ1QQftidZ2QQtZkm

 

[Ogri the trog]

Right I'm off to get some brass out of the store and get my self on the lathe fire piston here I come

I'll have to wait till I'm back on shift, but I'll be doing tha same. I had dismissed brass as a possibility initially, thinking that it would conduct too much heat away, which is why I made my first out of delrin/plastic and aluminium.

ATB

Ogri the trog

 

[Beakytzw]

Shadow, cheers mate. I spent the whole day dodging work (not unusual for a soldier I hear u ex crabs say!) just so I could sit and play with my new fire piston. John, this works a treat. Even tho i got no real instructions, I just played a bit and got an ember after about 8 tries.

Only problem is...I have ran out of charcloth....ok I did over do the practicing a bit. I can now get an ember on every second attempt even had a few consecutive embers. John, can you give me some details on the tubing you get? I would like to make sure i have a good supply of it also what did u use for a lubricant, want to make sure i have the same stuff on here as it works don't want to faf around trying out different oils and tubing when you have cracked it already.

This piston is nice m8, a cracking job. A good weight, a nice feel to it and simple to use (no smart remarks from you crabs out there ). Its nice and small, slips into my pen holder in my inside pocket perfectly.

Once again John thanks buddy, I am one very happy chap.....also ever noticed how easy it is to amaze a female squaddy? I had 2 of em standing staring at me open mouthed for about an hour today, going ohhhhhh every time i pulled out the piston and it was smoking...... does that sound right?????

 

[shadow57]

Glad it works for you,

a. I have used 4mm silcon tubing cut into thin slices for my latest piston rings (purchased from aquarium shops) The one you have is rubber so I will send you some through post.

b. The lubricant I used is Olive Oil.....but any oil or parrafin seems to work.

c. Tinder is made from cotton roll used to wash cars. I am about to run some tests on horse hoof fungus that TODDY kindly sent me.


You should see the latest Type 3 Mark 1 Brass Fire Piston

This model incorporates "CBE Technology". Supa champhered 60 degree cylinder bore entrance. This helps to facilitate the new sleek TURBO driven piston, fitted with the new technology SILICON PISTON RING.

Piston also incorporates additional REAR STORAGE facility for tinder storage tested to 20 atmospheres.

ABS: ANTI-SLIP SYSTEM grooves are incorporated into the piston.

New models also incorporate a name embossment onto cylinder , so that police can easily identify your piston.

Latest News

A new generation of piston, is secretly being developed in the CDT department at school, during lunch-times. Strict security is in force ...If Headteacher finds me working in the CDT workshop and not on the school computers, she will throw a wobbily. CDT teacher is no problem as I can easily drop him in the pooh if need be. Pupils sworn to secrecy during lunchtime. They love it.


Super

 

[Hoodoo]

If you don't want to drill out a solid piece of brass, you might try using brass pipe, like John Rowlands did in Cache Lake Country. You can see a diagram of his piston here.

 

[shadow57]

Yes...That's where I got my original idea from.

I tried brass tubing and it worked.

But the tubing wall thickness that I had, was a bit thin ,and could dent easy if dropped and piston would be knacked

I am using the brass bar so that I can make screw together piston fittings to store tinder, pins, washers etc so that the unit contains everything..

Great fun experimenting..... keeps me happy ....even though people at school think I'm nuts (At least I know I'm nuts)

Waiting to see if anyone wants to trade something nice for a piston

 

[shadow57]

Hello all

Well I have been playing with the brass again and this is the latest piston.

As you can see there is now storage areas for char and seals.

 

[Big John]

Looks very nice Shadow - I take it the knurnling was done on a lathe?

 

[shadow57]

Yes John a lathe was used to do the knurling. I keep playing with ideas how to make the piston better. The biggest problem is getting suitable piston rings. At the moment I am using silicon rubber tubing which is cut by hand...not very accurate.

Adding little storage areas on the the ends of the piston is being tried out just now. Maybe a minature compass on the end????

Its just a bit of fun making them...in reality if I wanted to use a primative method for fire I would use flint and steel every time.

Thanks John

 

[jdlenton]

A new generation of piston, is secretly being developed in the CDT department at school, during lunch-times. Strict security is in force ...If Headteacher finds me working in the CDT workshop and not on the school computers, she will throw a wobbily. CDT teacher is no problem as I can easily drop him in the pooh if need be. Pupils sworn to secrecy during lunchtime. They love it.


Super

and I thought that I was the only network manager in a school the hid in the CDT room and made buscraft stuff instead of fixing PC's wilst avoiding the head and the head of department. useful haveing a workshop across the corridor from my room(pit) I can leg it back to my pc sharpish.

going to get some bow staves cut soon don't know how i'm going top explain those to the boss

James

 

[shadow57]

No Probs getting bow staves into school....put them in a large fishing rod bag The only reason I stay at school is that I get to use the CDT room the pay is crap as you will already know..

Things I have done in the CDT include.

Ash/ Yew Longbows
Forging Steel/Flint
Forging Medieval Arrowheads
Forging Knife
Leather belts, Quiver and bracers
Mini Stoves
Fire pistons
Linen Shirts
Spinning flax into linen
Retinning copper pans
Wooden bowls
Nocks for bows

and more...................

Oh yes.. I gave the CDT teacher a fright :aargh4: when I showed him my next project (I was only joking) [Link removed, that's a no, no Shadow. ~ Martyn]
The Kids love watching me unofficially making bits and bobs...teachers think I'm mad.

I wind them up by saying

"Teacher's are adults amongst children but children amongst adults"

(Sorry to any teachers reading)

 

[Ed]

(Sorry to any teachers reading)

No offence taken

Ed