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How To Make... Your Own...ergo Catapult... From Start To Finish...


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First off let me say... this is my own way of making them... and isnt the only way to gey the end result...

 

I have had numerous PM's asking how i make them... so ill explain...

 

Hopefully this will make people realise how easy they are to make... and maybe give them a go... with their kids and so on.... it makes a great father/son(or daughter) ..project ;) ...

 

An 'ergo' catapult is one that is nicely shaped to fit your hand... and thats what im making...

 

So ill begin....

 

 

Start off by finding a natural fork from a tree.... try and get it as even/perfect as you can... but its not always possible... once you start looking... youll be amazed at how many there are! ...

 

Be sure to cut the fork a few inches longer than needed! ...

 

You can dry the fork by leaving it in a warm place such as an airing cupboard for a couple of weeks... or in a microwave... but be careful!

 

For this i have an OAK fork... its a little imperfect as on forks thicker than the other... but we will work with that...

 

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Using some rasps you need to work out all the knots... so the fork is smooth-ish...overall...

 

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Cut the forks... leave a little bit extra for final measurements... a couple of CM or so should be plenty...

 

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Work on the forks using rasps... your aiming to make each fork equal in diameter... size etc... so its best to leave the smaller one... and work on the bigger side... touching up once your done...

 

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Do your best to keep the 'cup' of the fork as even as possible... with a nice 'U' in it...

 

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Once you have worked the forks roughly... it time to mark the grooves for your fingers...

 

Normally i would just put a small mark and file it... but for illustration purposes...

 

I held the fork as was comfortable... and marked where my fingers sat... and ended...

 

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Clamp and file the lines... where your fingers will sit... only file to where the tips of your fingers will sit...

 

This will mean you get a nice grip...in the same position each time... and therefore a consistent shot...

 

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Carry on with the rest...( three) ... file them as deep as you wish... checking the fit... and how comfy it is as you go along... it should fit perfect...

 

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Cut the bottom off as you wish...

 

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Next grip the fork as you wish... mark off the fork tip just above your fingers...(for OTT...

tabs only!)... for other types you will need the forks a little longer...

 

The aim is to get them as even as possible.. but low to your fingers...

 

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Using files... or a dremel/ rotary tool... take away the roughness of the rasps...

 

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AFTER this... i notice the forks werent even...

 

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See how it isnt a nice 'U' ... so i sorted that out with the raspss..

 

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Sorted! ...

 

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The front edge of the forks need to be rounded...to reduce wear on the tabs... and if your fitting theraband gold or flats... the fork tips need to be SUPER smooth and nicely rounded or the edge will.cut the bands...

 

But for tabs... just a little rounding is needed ;) ...

 

The next stage is SANDING...

 

The level to which you sand is personal choice... some sand to 1500grit...which is silky smooth... but 800ish even 600 would be ample...

 

Infact... no sanding is required... its all aesthetic... and down to the final looks... (aslong as the forktips are smooth)... you dont have to sand at all... but a little would look better ;) ...

 

Start off on a low grit... and work your way to a higher grit...

 

This was started on 150grit....

 

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Working up the grits to 240..400...then i finished on 800...

 

I hate hand sanding! So often scrimp on it :laugh: ...

 

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Even my lad helped sanding this! (Good father/son) project ;)

 

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Once completely sanded...

 

Your onto your finishing...

 

The choice is vast...

 

But here is a couple i use/ have used...

 

-Teak oil

-danish oil

-wood dye

-50/50 mix of spirits and BLO

-BLO

 

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For this i will use BLO (boiled linseed oil) ...

 

Its cheap...easy... and good for the wood ;) ...

 

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Just sit the fork in a tub of the linseed oil...

 

It may float to the top... which is fine...

 

You can get around this by sitting a small weight on the wood... to keep it submerged...

 

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Length of time to let it soak varies... i have found 4-6 hours is plenty... but others soak for...12...18...24 hours...

 

Once soaked... wipe with a rag... and let dry for a few hours...

 

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The final finish is again your choice (isnt it always :D ) ...

 

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I use a wood enricher (lord sheraton) i got from asda...

 

Wipe on....

 

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Wipe off...

 

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A few coats off that... and i finish off with some beeswax...

 

You just wipe it on... leave for 15 minutes and then wipe and buff off...

 

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As a final protectant... i may give it a coat or two of polyurethane spray... a clear spray varnish... that protects the wood and is impervious to water and also prevents scratches...

 

Once its on though... its on for good... so will see how i feel...

 

At this stage the slingshot is finished... or the frame/fork is atleast...

 

Tabs need to be added... or flatbands... and then its complete...pretty easy from here...

 

If you need any help putting tabs or flatbands on.. let me know... theres videos on youtube im sure...

 

Hope this was informative... a but long winded... but ive made it as easy as possible...

 

A free... natural catapult... that fits your hand like a glove...

 

Thanks...

 

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Edited by B.P.R
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Finished article?....

 

Here goes....

 

Attaching tabs...

 

Tabs are an easy attachment method for tubes on naturals....known as 'gypsy tabs' ...

 

Cut your lengths of leather depending on the size of the slingshot... they just need to look in proportion with the frame...

 

Wrap your theraband round the forks once to get a good grip...

 

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Place your tab into place... and wrap the theraband (TBG) around...and around...and around...

 

Make sure its super TIGHT!!.. dont want a tab in the eye! ...

 

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Place a small loop of cord over the TBG ... and wrap over another few times...

 

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Once happy... slip the TBG....THROUGH the loop in the cord....

 

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Then pull the cord 'up'... so the TBG 'pops' under itself....

 

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Then trim off the excess...and pull all the way through...

 

Repeat on the other side so they are both uniform...

 

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NOW YOUR READY FOR BANDS...

 

if you have already made bandsets up.. like i do...

 

Then you need to fit them...into the tab loops... before fitting the tabs... which is easiest...

 

But for this only... i will show you how to make the bandsets.... and attach at the same time...

 

So..

 

Take your tubed elastic... waxed twine and tying jig (tying jig not needed... but makes life 100 times easier) ...

 

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Taking that youve tied one end if the elastic to the pouch (youll know how in a minute) ...

 

Loop the tube through the tab and slip through the hole in the pouch...

 

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Fold the tube over the edge of the leather pouch... and secure in the jig clip... (improvise where you need) ...

 

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Using the CONSTRICTOR KNOT... tie the waxed twine to secure the tube...

 

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And trim the excess (leaving a little excess over) ...

 

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Do this on each end of the tube... either prior to attaching the tabs... or through the tabs as ive show...

 

This is so easy... it sounds more complicated..cutting the stages down... it soon becomes second nature...and you can make these bandsets up in a couple of minutes...

 

The finished article...ready to shoot...

 

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PUT A FORK IN ME...

 

IM DONE!

 

hope this helped :thumbs: ...

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Thanks .338...

 

I know most on here already know all the above... and more... and will have their own way of doing things....

 

I just thought it would be good for a basis for new members... or members who havent thought of making a slingshot... to get out and knock something up...

 

Im far from an expert... and relatively new to slingshots compared to most...

 

But theres no harm in sharing what you can...

 

It would be good to see tutorials from others...on how they do things...

 

As ive learnt most as i go along...

 

I am glad to say a couple of people have PM'd me saying....that this helped them make their own...

 

Which i great to hear...

 

Here is chrisyboy's catapult he made :thumbs: ...

 

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Edited by B.P.R
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  • 2 weeks later...
  • 2 weeks later...

Big thanks to BPR for putting this tutorial up, I pm'd him after reading it and bought the catty that he made in the tutorial from him ....... Then went on to buy another 2 from him the same week :-) as they are a top bit of kit, I'm now using one of his multiplex catties, that I think is very well made and very accurate, What a top bloke BPR is, great service and always on hand for any advice!! Anyone thinking of buying a catty, I'd definately recommend his work!! Cheers for all your help lee

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  • 2 weeks later...

 

 

Cracking tutorial you've inspired me to make one !

Thats great mate! ...

Let us know how you get on ;) ...

will do mate out first thing looking for the fork/prongs .

Sounds good mate... post pics of what you find and progress pics ;)

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