[Weed Elm]

Spent a few hours on the home made section. Great stuff. Geared more to Y branch than cut out. Didn't find any discussion on this topic in the home-made section. How critical is it that the diameter of the forks be the same or very close assuming the diameter is sufficient to prevent flex? I am working on the below. Diameter of large fork is about 1.2". Smaller fork is about 1.1". Made from a weed / invasive elm, probably Chinese or Siberian. Thanks for your input.

 

[SJAaz]

Not at all. What ever feels good and solid in your shooting hand.

 

[ghost0311/8541]

That looks good

 

[NSFC]

Semitry just looks pretty.

Even if the forks have flex you can support then with how you hold the sling. Just keep the bands on the light side.

 

[Weed Elm]

Thanks for the replies. More as it becomes relevant. Working on finishing this weekend.

NFCS, new to this. What do you mean by "keep the bands on the light side?" My first thought is that the bands should wrap around to the outside of the forks. If that is not what you meant, will you explain please? Yesterday I spent about 10 minutes trying to figure out BLO - boiled linseed oil in some posts that were tracking home made slingshots so I might be off on my thought about what it means.

 

[SJAaz]

You'll get it. Just takes some getting used to the vernacular. Light bands as opposed to heavy bands meaning amount of force needed to pull back to anchor point.

Somewhere on this forum, there is a list of commonly use "terms". Perhaps use the search program in the upper right of the home page.

 

[Weed Elm]

Thanks SJazz. Perhaps he meant light bands if there is flex in the forks. Diggin your truck by the way.

 

[Sean Khan]

Yesterday I spent about 10 minutes trying to figure out BLO

BLO... Bacon, Lettuce, Onions?

What's there to figure out?

 

[Pebble Shooter]

According to the Janka wood hardness tests chart, Elm is not among the strongest woods:

https://ejmas.com/tin/2009tin/tinart_goldstein_0904.html

1 inch thickness on the thinner fork limb should be OK, but I would personally cut the fork limbs shorter (see image), as this will remove a large part of the risk factor in terms of structural strength. An inner fork width of 4 cm (1.57 inches) should be fine for ammo up to 9 mm (.38 cal.), and a reduced fork height should allow for flat bands with a suitable draw weigh for that purpose.

I would in any case lock the forks between vise clamps and push against the handle with fair force: if it handles that, you should be OK. Even if the outside of the wood looks fine, this is a good way to ascertain the state of the inner wood sections of the forks. There can be interesting surprises sometimes, and not the kind you want on a natural slingshot.

You do not want broken sections of forks flying back at you. :hmm:

I would stick to a simple wrap & tuck groove placed on the front side of natty frame facing away from the shooter to maximize fork limb strength.

 

[Weed Elm]

Thanks Pebble shooter. You are correct that elms are not considered "hard woods" I plan to cut the forks down a bit generally about where you suggested. The more I sand and shape, the more worrysome the knot on the right fork becomes. I plan to leave the handle at length since the grip area will be above that little branch. I think it gives it a bit of ... something. following your advice, I placed the slinghsot as is between 2 concrete blocks and clamped a pair of straight calipers to contact the floor and bottom of the slingshot. There was less than 1/16" compression over 10" length across the points of the calipers after I bounced on it. My bathroom scale puts my bounce at over 400 pounds so I'm confident that it will hold to 60# draw. I don't know what the draw will be but I am unlikely to draw to 60#. My strongest recuve bow is 45# and that is about my limit of "fun".

I planned on a band groove on the front side for latex tube bands shooting BTF rather than removing material for a flat band OTT configuration. If I do, I might leave the length as is with the groove just below the knot void. That gives me a width between the forks of +/- 1.75". I plan to shoot 1/2" marbles so it is a bit tighter than I would have engineered but I did not engineer for that pesky knot to be a void. And the knot is on the larger dia fork.

And it probably does not need to be confirmed but I'd prefer not to have something come back towards my face under tension. So thanks much for the advice, direction and input.

 

[AUSSIE4]

That looks great! If it feels strong with no or very little flex then it should be a great shooter.

 

[NSFC]

According to the Janka wood hardness tests chart, Elm is not among the strongest woods:

https://ejmas.com/tin/2009tin/tinart_goldstein_0904.html

1 inch thickness on the thinner fork limb should be OK, but I would personally cut the fork limbs shorter (see image), as this will remove a large part of the risk factor in terms of structural strength. An inner fork width of 4 cm (1.57 inches) should be fine for ammo up to 9 mm (.38 cal.), and a reduced fork height should allow for flat bands with a suitable draw weigh for that purpose.

I would in any case lock the forks between vise clamps and push against the handle with fair force: if it handles that, you should be OK. Even if the outside of the wood looks fine, this is a good way to ascertain the state of the inner wood sections of the forks. There can be interesting surprises sometimes, and not the kind you want on a natural slingshot.

You do not want broken sections of forks flying back at you. :hmm:

I would stick to a simple wrap & tuck groove placed on the front side of natty frame facing away from the shooter to maximize fork limb strength.

One shooter opinion to another.

Dont cut the unique handle end!

Unless you want it to look like every other cookie cutter natty.

Ive been following this beautiful build. If your not happy with it Ill trade/$ for her.

Just dont make her look like the rest please.

Unique is beautiful. N.S.F.C Never Settle For Common

PM me.

 

[NSFC]

Thanks for the replies. More as it becomes relevant. Working on finishing this weekend.

NFCS, new to this. What do you mean by "keep the bands on the light side?" My first thought is that the bands should wrap around to the outside of the forks. If that is not what you meant, will you explain please? Yesterday I spent about 10 minutes trying to figure out BLO - boiled linseed oil in some posts that were tracking home made slingshots so I might be off on my thought about what it means.

I was referencing the band strength to fork thickness.

Depending how you hold this piece of art you could support the forks with your fingers. If you wanted to use heavier bands which would mean you throw bigger ammo. Or keep the bands/tubs on the lighter end of the spectrum.

When I shoot this(my new favorite) sling shot, I would round over the tips and go for OTT (over the top). Gypsy tabs might be something you consider. I found them to diminish hand slaps.

Stay orriggional ! :screwy: :rofl:

 

[Weed Elm]

UPDATE - between several coats of linseed oil, I tied up latex tube but didn't it make it correctly - one of the ties started to slip after a couple shots. Going to watch some more videos to improve my band manufacture. The forks are a bit long and create a lever effect so I might cut them a smidge as longs as I can keep clearance between them. Might change to OTT if I cut the forks. Could cut a groove with a rasp for tubes or might just go flat for strap bands. Latex tube is cheaper but bands seem to pull easier. Bands might be less power but I'm shooting at cardboard and planning to max out at 40 yards, maybe less. Gotta walk to the target so 40 yards seems like enough walking. Didn't cut the handle - too unique to cut off and doesn't affect performance unless I get in a shoot out at high noon with Clint Eastwood (hum Good Bad & Ugly music here). More as the world turns. Thanks all for the conversation, comments and advice.

 

[flipgun]

https://slingshotforum.com/topic/11772-slingshot-glossary-and-slang/?hl=%2Bglossary+%2Bslingshot+%2Bterms

Why isn't this pinned or a sticky or some other computer term? :imslow: