26 replies to this topic

[BlackFox]

This isn't the first Crossbow plunger head remedy I've posted. However, my first attempt was unsatisfactory. Although for the first few shots, I was getting fairly high ranges, the accuracy that I love my crossbow for was gone. Furthermore, the new O-ring I made folded over just like the original plunger head after several shots making it effectively useless. I was back to square one.



Here are all my attempts at fixing this problem. I spent two hours working on this yesterday and nothing was working. Like a teenager on a first date, I was desperate to shove something airtight on the end of that rod. That's when it hit me:



Plastic lunch bags. I had always been curious about the sealing properties of these. But that's for later. You have to make your actual plunger head first.



You're going to need one of the rubber washers we all know and love. I got mine from Ace Hardware. The one I used was 1 1/4" in diameter with a 3/8" hole in the center and was 1/8" thick. That last dimension is troubling. It's way too thick to be an effective plunger head. So we need to cut it down (Prepare to get lots of rubber shavings on your hands). The easiest way was to squeeze in a vice so you're looking down on the thickness of the washer and dremmel it in half.



Use the fragile 1/64" cutting wheel for this, the reinforced ones are just too thick. This takes a long time, be patient and try to make your cut even around the circumference of the washer. Once you've gone all the way around as deep as the cutting wheel can reach, use a razor to cut apart whats left and seperate the two halves.



There, that's more like it.
Ok, now for the condom part. Place the washer in one corner of your plastic bag and fold it all the way to one side.




Now fold it the other way until you've got a little square of plastic bag.



Now you can hardly tell that's an O-ring, huh?

Find the hole in the center of the washer and poke something sharp through all that plastic. Wiggle it around to widen it. Now you need to get it on the end of that plunger rod. Be VERY careful here, it's extremely difficult to force the new plunger head on without putting stress on the plunger rod. I had mine bow out to the side at one point and needless to say, I nearly had a heart attack.



Voila, your... um, plunger head.

One of the key flaws in my first plunger head write up was the lack of support the pins provided in keeping the O-ring from folding over itself. I made sure not to make that mistake twice.

I used a 7/8" washer with a 3/8" hole in the center to stablize the plunger head. Cut a 3/8" gap into the washer so you can slide it onto the plunger rod.



That's it! Close her up and get ready for action.



The ranges amazed me.

No Bungies:
63'
72'
72'
Average: 69'

Bungies
89'
102'
103'
Average: 98'

And with perfect accuracy! I was almost crying. Let's not forget that's a frickin bag on the end of the plunger rod!

So there you have it; the Condom Bow.

Edited by BlackFox, 27 August 2008 - 12:33 PM.

[Norther of Heaven]

Cool, smart idea.
But i'm not sure how long the plastic will last like that.

[BustaNinja]

I thought you were gonna use an actual condom.

I right away thought about all the jokes made by everyone about lubricant and all the gay jokes made on the haven and it made perfect sense. To bad huh?

Great way to make a good ghetto fix. Hope it lasts.

[Icespartan 1114]

I like the name

[Norther of Heaven]

I thought you were gonna use an actual condom.

I right away thought about all the jokes made by everyone about lubricant and all the gay jokes made on the haven and it made perfect sense. To bad huh?

Great way to make a good ghetto fix. Hope it lasts.

Speaking of which, Random fact:
I once used KY to lubricate one of my guns.

[Bomberman]

I like the name

So why are you even posting? For the sake of posting?

But this is real improvising. I never would have thought of a plastic lunch bag. Now, have you lubed your Lunch bag o-ring? If you have, or if you do, does it eat away at the plastic? That's the only thing I would be worried about with this. Other than that possible setback, good job! Very creative.

[Aimless]

Cool, smart idea.
But i'm not sure how long the plastic will last like that.

Well, the plastic bag should last longer than an actual condom, none the less, the constant thrusting will eventually destroy it.

Edit: To Bomberman: Silicone grease/oil should be safe for most if not all plastics.

Edited by Aimless, 27 August 2008 - 01:21 PM.

[BustaNinja]

I thought you were gonna use an actual condom.

I right away thought about all the jokes made by everyone about lubricant and all the gay jokes made on the haven and it made perfect sense. To bad huh?

Great way to make a good ghetto fix. Hope it lasts.

Speaking of which, Random fact:
I once used KY to lubricate one of my guns.

Random fact #2.

I used KY jelly on my penis to have sex.

Wait... are we still talking about bullshit? Or are we back to reality?

[BlackFox]

Well, the plastic bag should last longer than an actual condom, none the less, the constant thrusting will eventually destroy it.

I actually did use silicone lube, but even if the bag deteriorates over time, there are 299 more to replace it.

Thinning down that washer just seems like way too much work.

I suggest you visit any auto parts counter and ask them about what gasket materials they have. It's possible they even have something very close already. More likely, you'll get several choices of good raw material you can cut yourself. You'll probably want a punch of some kind to make the center hole. I have a cheap set of "leather" punches. Get the outer diameter close with some heavy duty scissors, then chuck it some kind of arbor in a power drill, and sand the edge to final size.

The difficulty is that the plunger tube gets thinner the farther down you go. The 1 1/4" washer just fits in the opening, but it would never fit towards the back. If you've seen the stock plunger head, it's actually only about 1" in diameter with a flexible skirt that contours to the inside of the plunger tube. I've only been able to replicate this with the bag.

I think what you were suggesting was to more or less lathe the piece on a drill, right? While that might have possibilities, I don't think I could accurately sand it. And as explained above, any piece thick enough to lathe will be too thick to fit down the plunger tube. But thank you, I never thought of using a drill to spin the piece.

Edited by BlackFox, 27 August 2008 - 01:44 PM.

[BlackFox]

Do you think xbow owners would pay a few bucks for a good substitute?

Oh yes. I'd buy one.
Tell me more, please.

[Draconis]

Random fact #2.

I used KY jelly on my penis to have sex.

Burn #1: "Couldn't get her wet, eh? Try going down on her."

Burn #2: "It's not really 'sex' when it's with your hand."

Sorry, couldn't resist.

*on topic*

I think new silicone plunger heads to match certain much loved guns would be awesome. The crossbow, sawtooth, SS1, etc... Pretty good idea with the bags, though. Even if it does turn out to be rather temporary.

[BlackFox]

Pretty good idea with the bags, though. Even if it does turn out to be rather temporary.

Somewhat temporary: It's too soon to say really, but the folded bag is reaaally thick. If anyone cares, I'll post when it fails.

One completely seperate note I forgot to mention in the original post is that the Crossbow has been slightly silenced by the cushion of the bag.

[rork]

Goddammit! Now I'm going to have to try this on a SNAP, if only for the hell of it. It will pretty sweet to be able to claim bragging rights over the fact that you shoot people with a gun that includes a sandwich bag as an integral component. ~Rork

PS: it would be nice if you would update with info regarding durability...

[BlackFox]

Basically, it's closely related to the process I used to use for duplicating parts, as a builder of plastic model kits (IPMS stuff). For the most part, we used RTV rubber to make molds, based on prototype parts, and then cast resin duplicates in those RTV molds. That way if you need 100 of something you only scratchbuild the first one. Sort of turn the process inside out, and the RTV part can be the end product.

Very interesting. I was thinking this might be something do-able at home, but it sounds outside my skills. I just repair whatever breaks on me

Edit: Will do, rork.

Edited by BlackFox, 27 August 2008 - 05:15 PM.

[mystefansdontflystraight]

Looks cool. I still think that my simple repair is easier, and more functional. I gotta put up a write up one of these days.
Good job, simple and effective.

Edited by mystefansdontflystraight, 27 August 2008 - 05:39 PM.

[BlackFox]

Looks cool. I still think that my simple repair is easier, and more functional. I gotta put up a write up one of these days.
Good job, simple and effective.

If you're going to post a write up, should I hold off on asking what you did? What happened to your plunger tube?

And thanks!

[Renegademilitia15]

Nice! now your xbow doesn't suck anymore!

Actually a condom might really work because of the O-ring like thing at the end of it. Or a latex finger cover, those might work as well.

Can't wait to see it in action!

[mystefansdontflystraight]

Looks cool. I still think that my simple repair is easier, and more functional. I gotta put up a write up one of these days.
Good job, simple and effective.

If you're going to post a write up, should I hold off on asking what you did? What happened to your plunger tube?

And thanks!

It is really hard to explain. I kept the plunger tube. But my xbow went from shooting 25ft to 95.
Just wait for it, I am just getting a new job, so I'm kind of busy.

[BustaNinja]

Random fact #2.

I used KY jelly on my penis to have sex.

Burn #1: "Couldn't get her wet, eh? Try going down on her."

Burn #2: "It's not really 'sex' when it's with your hand."

Sorry, couldn't resist.

*on topic*

I think new silicone plunger heads to match certain much loved guns would be awesome. The crossbow, sawtooth, SS1, etc... Pretty good idea with the bags, though. Even if it does turn out to be rather temporary.

How is telling me to go down a burn?

But dude, you need to go down to get a girl wet? I dont think you have enough points toward your sex appeal stat.

AND LIDNSEY LOHAND DOES TOO COUNT! DONT HATE!!!

I would really like to see the Condom Bow in action and something relating to the seal just so I can find out if its an acceptable substitute. Or is it more of a temporary fix?

[BlackFox]

(Lots of sex related stuff I was asking for when I came up with the name)

I would really like to see the Condom Bow in action and something relating to the seal just so I can find out if its an acceptable substitute. Or is it more of a temporary fix?

Are you asking for a video? I can try and get one up if you want one.

The seal is sufficient. I'd say it's 80% what the stock plunger head was. I can put my hand over the coupler and the plunger rod will slowly retract to its uncocked postition.

While I doubt the bag will last permanently, I do think this will be semi-permanent. Because of the ease switching out plunger heads and the abundance of plastic bags, I think the future of my Crossbow has protection, if you know what I mean.

[Icespartan 1114]

I know that I have already commented on this post. But I have one questions about this. Would the original plunger head actually increase the range of the crossbow more then having the plastic bag.

[BlackFox]

I know that I have already commented on this post. But I have one questions about this. Would the original plunger head actually increase the range of the crossbow more then having the plastic bag.

You can comment more than once on a topic, you know.
As far as I can tell, the ranges I'm getting now are more or less the same as I was getting when the plunger head was performing well. That being said, I never did range test it when it was at its best. It's kinda an awkward timeline.

-Crossbow works great, amazing ranges but nothing official
-Plunger head gets a crease, 40-60'
-First plunger head replacement: 80-90' for about a day.
-Original plunger head magically works better when I decide to give it another try: 90-100'
-It creases again and I do this mod: 90-100'

[BustaNinja]

(Lots of sex related stuff I was asking for when I came up with the name)

I would really like to see the Condom Bow in action and something relating to the seal just so I can find out if its an acceptable substitute. Or is it more of a temporary fix?

Are you asking for a video? I can try and get one up if you want one.

The seal is sufficient. I'd say it's 80% what the stock plunger head was. I can put my hand over the coupler and the plunger rod will slowly retract to its uncocked postition.

While I doubt the bag will last permanently, I do think this will be semi-permanent. Because of the ease switching out plunger heads and the abundance of plastic bags, I think the future of my Crossbow has protection, if you know what I mean.

Resisting more condom jokes....

Glad to hear its stable and not just a temporary fix to do before a war. I may think about doing this to a BBB if I ever have problems with one... or ever buy another one.

[BlackFox]

Resisting more condom jokes....

Glad to hear its stable and not just a temporary fix to do before a war. I may think about doing this to a BBB if I ever have problems with one... or ever buy another one.

Ah, this is great fun. I think I'll call my next mod "Oral ...." even if it has absolutely nothing to do with the modification.

I'm glad to hear this is helpful to others. I'm not familiar with the BBB, but I'm sure this will work fine.

[nerfboi]

Have you tried filling the original plunger head with hot glue? and while the glue is still how, it will make the plunger head comform to the plunger tube, and while drying, it will make a somewhat perfect seal? I don't really know semming as I have never tried it. I just thought of it.