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T da B's Content
There have been 64 items by T da B (Search limited from 21-March 93)
It's good to be browse these forums again after a long hiatus. I've shifted all my learning efforts over to the automotive world after putting a pause on my Nerf modding, but I forgot to share my old cubicle photos from work:
The mounts are all custom made from cardboard and T-shaped pushpins
For those that care about what my mods look like nowadays:
After wiring it up along with a new fuel pump and relay, I'll be throwing in a centrifugal supercharger--should be a fun learning experience, just like Nerf!
I"ll be back someday, my friends.
~T da B
- Extension spring for better trigger feel
- Extended shoulder stock
- Simpler way to attach handle
- HDPE handle instead of wood
- Adjustable barrel spacer
- Set screws
- Clear everything!
Velocity was achieved with a 14'' barrel, 9-dart hopper, and 1.25'' slugs. You can read the full writeup here.
Here's a little something I whipped up to keep the barrel stable on my bullpup. It takes the guesswork out of fabbing your spacer by hand, and it looks pretty nice. I didn't make the big piece quite tall enough, but you get the idea:
Hope this helps,
You invented this independently. That's NOT a bad thing. It just means you could improve your powers of observation.
Thanks for the feedback, Just Smug Bob. So Nerf ports their plunger heads. That's wonderful--if you actually use stock plunger heads. What separates this design from anything Nerf has ever put out is the fact that multiple ports along the perimeter expand the seal in all directions while firing.
- HDPE grip
- Solvent welded front bushing
- Longer screws for everything
- Extension spring instead of ghetto rubber band
- Ported Piston plunger head
- Plunger padding
- Smaller holes at the sideplate connection points
Velocity (max) measured with a 12'' slide breech and 1.25'' #6 slugs. Gonna try to Chrony with some other barrel setups and update with some Chrony pics.
Hello lady and gentlemen,
After finally getting around to thoroughly testing this prototype, I'm very excited to present you all with some dope new technology that you may not have seen before! The idea is not mine, but I'm "porting" it over from our sister sport--Airsoft! First of all, let's quickly go over the advantages and disadvantages of regular old O-ring plunger heads:
- Incredibly cheap
- Take up very little real estate
- Easy to maintain
- Long-term reliability
- Low friction
- Sealed breeches don't allow air into the plunger (vacuum loading)
- More machining required
- Tight tolerances to get a working plunger head
The Ported Piston, or PP is a modified O-ring plunger head that eliminates the first disadvantage off the list. Here is a picture to illustrate:
Of course, you have to imagine a dart plugging up the right side of each plunger to understand the real benefits!
For this write-up, I'm building a plunger head for 1 1/2'' OD polycarbonate tubing out of 1/2'' HDPE (cutting board). Start by cutting out a disc of HDPE with a diameter about equal to the ID of your tubing. Mark the center and draw 3 lines through the middle (or more if you want more than 6 ports). Try to keep the lines equidistant from each other.
Drill a 1/8'' hole through the center and tighten on a 1 1/2'' 6-32 bolt. Chuck in it in the drill press (if you don't have the luxury of a lathe) and file/Dremel it down until it slides into your tubing nicely:
Now use a rough file and a small square one to get a nice hamburger shape. Make sure the track is wide enough to allow the O-ring to slide up and down a little. Test the fit in your tubing constantly!
Now mark the holes on top--mine were 1/4'' from the edge. Mark the holes around the perimeter that will meet up with the ports on top--they should be lined up with the O-ring when it is slid downwards all the way:
Now drill the holes in the top to a depth of around 11/32'' with a 1/16'' drill bit:
Now drill the holes along the perimeter to meet the previous ones. I centered the disc as best as I could in my small vise and used my drill press. I literally looked in through the upper hole until I saw the drill bit appear at the end of the small tunnel.
To see if your ports are functioning properly, blow through the hole on top of the disc. Clear out any swarf with a paper clip--it is imperative that the passages be clear of debris!
Here you can see what the plunger head looks like when you prime the blaster--the O-ring slides upwards, exposing the ports, then fresh air can flow from behind the plunger up through the ports and into the plunger tube for the next shot. The O-ring is a 1 5/16'' OD O-ring from Ace.
And when you fire, the O-ring slides backwards, covering the ports. As an added bonus, air rushing in through the top ports pushes the O-ring outwards, improving the seal!
Slapped on a plunger rod:
And into my Ported Piston Plusbow (PPP):
After hundreds of shots worth of testing with various barrels, I'm getting the same performance out of my PPP as my skirt seal RainbowPump! Even with sealed breeches and rapid firing, there is no drop in velocity. Though this plunger head design required a lot of effort, the result is well worth it.
This was the max fps--the average was 260-270. It was achieved with a 12'' slide breech and 1.25'' #6 slugs. I hope you guys found this as awesome and intriguing as I did. No go forth and make yourselves a PP!
- 2'' shorter pump and plunger tube
- 8 1/2'' [k26]
- 1/4'' thick trigger
- HDPE handle
- Modified rear stock (no string stop)
Read the full writeup here.
Nope. Springs follow Hooke's Law, which states F=kx, where F is the force exerted, k is the spring constant, and x is the spring deflection. Full compression on a 6-7" long [k26] will not give you a force of 32 lbs. This thread discusses how to determine the force exerted by a shortened spring (since shortening the spring changes the k constant), using the constant that McMaster gives you (which is not the same as the k constant in Hooke's Law).
What you have to realize is that k changes when you change the free length. The force at full compression of a spring is directly proportional to the ratio between the free length and the active coils. Cutting down a spring doesn't change this ratio, so you get the same max load for all lengths. See this thread I started a while back.
Alright let me just ask this question right off the bat, how do I get similar power of a [k26] fully compressed on a smaller scale? That meaning, I want less draw same power.
I know that using a stronger spring than a [k26] can sometimes really hurt people. And surprisingly I don't want to do that.
I would like a 4 or 5 inch draw; anyone have any suggestions on how I can select the right spring?
Please feel free to call me an idiot if I have looked this over
I also know that there must be some equation I can use to calculate this, but I am not sure if I could use it only having a high school education!
Thanks in advance
Any length of [k26] will produce the same amount of power when fully compressed. 4-5'' of draw requires a 6-7'' [k26].
EDIT: I have found the solution! Unscrew the plunger rod from the front and pull it out. That is if you screwed on the plunger head. If you used the same technique ryan did on the plunger head you are not in good luck. Once the plunger rod is out you can just unscrew the coupler and disassemble. This whole deal seems like it came out of nobody using his exact design until now.
Good call! Fortunately I haven't built the plunger rod yet, so I think I'm all gravy.
I'm about halfway through my first homemade, a Ryan-style RainbowPump, and I've stumbled upon a startling realization. Upon studying the write-up, it seems like once the blaster is assembled there is no way to remove the plunger rod. Seeing as the front bushing/coupler will be solvent welded, the only way to remove the plunger rod is through the back. Unfortunately the internal coupler blocks the Rainbow Catch from sliding out the back, and the screws to remove the internal coupler are blocked by the plunger rod.
One of the design paradigms I swear by is modularity--all my blasters can be easily taken apart and maintained after they are built. I can't see any way to get the plunger rod out without drilling holes through the plunger rod, or drilling new holes in the plunger tube to hit the handle screws at an angle. Solution #1 might compromise the integrity of the plunger rod and solution #2 (aside from seeming impossible) would be a nightmare when putting the screws back in. Attaching the handle to the plunger tube with set screws would never hold up in the long term. Perhaps some of you guys with more experience than me can chime in--is it a design flaw or is there something I'm missing?
I browse the forums fairly regularly and sometimes I see something that really impresses me. In this case, it was actually a Longstrike! It's not often you get all hot and bothered by a blaster that absolutely blows stock. However, nowadays I see blasters in a different light than I used to. Now that I have the means to create any of my own components, there's no point in reusing Hasbro's internals at all. A blaster's worth to me is now measured in how good it looks and how easy it is to incorporate internals and other goodies. The Longstrike satisfies all my requirements, and just happens to have enough room for a 1.5'' PVC plunger tube! This mod is literally a wolf in sheep's clothing--the shell is the only thing left that's actually stock.
Here's the Longstrike I got for free:
The bolt was stuck, so the owner probably tried to open it up, realized it was solvent welded, and gave up. Sweet!
- 1.5'' clear PVC pipe
- 6-32 threaded rod
- 1 1/4'' to 1/2'' PVC bushing
- 6-32 Keps nut x4
- 3/8'' length 6-32 set screw x4
- 1/2'' length 6-32 set screw x2
- 1/4'' polycarbonate sheet
- 1/8'' polycarbonate sheet
- 6-32 nylon spacer x2
- 3/4'' length 6-32 screw x4
- 6-32 shoulder screw
- Small, strong spring for catch
- [k26] mainspring
- 1/2'' round Delrin rod
- Spud gasket (for toilets)
- 1'' length 6-32 screw
- 3/8'' length 6-32 screw
- #6 washer
- U-cup or piston cup ()
- Scroll saw
- Drill press
- Hand drill
Let me start out by saying that taking apart this blaster can be a huge bitch. There were orange pieces randomly solvent welded into place that actually kept the two halves of the shell from separating. Suffice it to say, I ended up using the Dremel as a samurai sword and severing anything in my path. I think it's a conspiracy by Hasbro to prevent people from modding blasters with too much real estate inside them. Anyways, eventually I cracked the egg. Start by cutting the plunger tube. It should be a whopping 14'' in length:
Now to prepare the front bushing. I secured the bushing in between two fender washers, tightened nuts on both ends, and put it in the drill press.
I used my "ghetto lathing" method to shave down the bushing with a Dremel until it fit nicely into the plunger tube. Use some PVC solvent to permanently attach the bushing with an airtight seal:
Now for the worst part of the mod--Dremeling the shell to fit the plunger tube. You can make things a little easier by cutting out the gloryholes that I did:
Dremeling the shell proved so frustrating that I even forgot to take a picture of it. Just keep checking the fit with the plunger tube until it fits. The front of the plunger tube should be flush with the front of the shell as well. Anyways, let's finish up the plunger tube. This requires the construction of a Rainbow Catch. I did a write-up on how to make a 1.5'' Rainbow Catch with no templates here.
Stick it in the back of the plunger tube and mark where the shoulder screw will pass through. Drill the hole with the 5/32'' drill bit, then use a small screw to hold the catch in place for more drilling.
Drill four holes with the 7/64'' drill bit through the plunger tube and into the inner ring of the catch. Tap them all.
Now that the rear end is prepared for duty, it's time to put the threaded rod through the front bushing. Drill through with the 7/64'' bit, tap, and insert the threaded rod. Drill 9/64'' holes in the shell at the front for the threaded rod. Add glue around the threads to prevent air leakage. Fail to do this and you won't get the perfect seal!
Put the plunger tube in place and enclose it in the shell. Then drill a 7/64'' hole through the shell and plunger tube on either side towards the rear of the blaster. Expand the holes in the shell with the 9/64'' bit. This step is just to insure that the plunger tube has adequate support.
Last order of business is plunger padding. I used a healthy amount of toilet gasket to kill some dead space and insure that the blaster doesn't destroy itself:
Now on to the plunger rod. Cut a 14'' length of Delrin rod and drill (and tap) one end of it with the usual 7/64'' drill bit.
Here is my plunger head. From left to right: 1'' screw, #6 washer, 1/4'' polycarbonate disc, <1/4'' polycarbonate disc, U-cup, 1/4'' polycarbonate disc.
In order to prime the blaster you need to fabricate something here is what I made:
I attached it to the end of the plunger rod with a couple of 3/4'' screws. Later I ended up trimming down the sides, since I was getting some facerape holding my head against the stock while firing.
Here is the plunger rod assembled. As you can see, my U-cup was a bit large. Regardless, the seal is perfect. I have discovered recently that 1.5'' OD piston cups plunger heads are the ideal choice for 1.5'' PVC.
Don't forget to Dremel the back of the shell for the new priming rod:
Put the assembly in the blaster and get a friend. Prime the blaster all the way back and get a friend to make a mark right where the rod leaves the shell. The front of the catch notch will be cut 3'' in front of the mark:
Reassemble everything again, and we're almost through! Here are some shots of the completed plunger tube:
Now for the final challenge--making the trigger! Obi, the original creator of this mod cautioned that this would be the hard part, but I thought about it for a while and arrived at a simple and elegant solution. First, a piece of the shell must be trimmed in order to accommodate the trigger:
Here are some tentative schematics I used for the trigger. The final product was a bit taller and wider:
Here is everything needed for the trigger setup. The trigger is 1/8'' polycarbonate, the mount is 1/4'' PC, and the screw is a 3/8'' screw.
The piece of polycarbonate is 3/8'' wide and 7/8'' tall. It has been drilled and tapped with the 7/64'' drill bit and goes here:
The rest is simple:
And the rest is history! Put it all back together (without forgetting the rail mount pieces) and marvel at what the Longstrike wished it could always be:
Cutaways are nice, so you can see full compression in action!
Damn, what a blaster. It seems like even a 16'' barrel is no problem for this bad boy. With over 7'' of draw, this thing could actually put an eye out. Many thanks to Obi, the modder I followed--you are a gentleman, scholar, and general baller. Hopefully this writeup brings hope to those who have lost faith in the Longstrike. One thing I could have done better was move the priming handle closer to the plunger tube to avoid face-diddle, but it may be unavoidable with over 7'' of draw. Here is the average velocity:
Not bad, considering the plunger head is too fat. Perhaps my 16'' barrel was too short as well--I'll have to make a 2-footer for blasters like this! In any case, I'll be revisiting this blaster farther down the road for one final mod--a shotgun grip
Hope this helps!
One more idea: you might be able to "hopper" it with just a tube that gravity feeds into the front chamber!
Other things to check:
1. Trigger catch activator spring
2. Make sure black return spring isn't caught somewhere
3. Make sure the breech isn't getting stuck in the receiver (caused my brass breeched Stampede to bump fire)
4. If you can hear the gears spinning, but the plunger isn't being pulled then your gearbox may be F-ed in the A
5. Make sure the trigger catch is in the right way
Has performance been affected at all with the addition of the rod?
- Shave down the sides of the plunger rod
- Put in a spring stop at the rear of the plunger tube. I shaved down a 9/16'' washer, like many have done before me
Hope this helps,
I used a combination of Dupli-color vinyl dye and Citadel Layer hand paints for the paint job. Internals are all homemade, aside from the trigger and trigger catch. Read the full write-up at my blog.
Not bad. Rubber grommets are a pretty good seal, though they're a pain to get right. That's why mostly no one uses them. It looks like yours is hitting the wall with a whole side of the grommet. you would have been better off using a skirt seal.
Yeah, my grommet seemed to have a perfect fit before I lubed it up, then it expanded a bit after. I have read of this happening to others as well for certain types of rubber. Skirts are nice, but they are very tall/expensive. For this compact setup I will probably stick with the tried and true washer sandwich and rebuild my plunger rod for a longer spring setup.
Now grab your 3/8'' Delrin and cut a 6'' length of it. Mark the end for drilling:
Drill and tap the business end:
Cut your catch notch 4 1/4'' from the back of the plunger rod:
Drill a 9/64'' hold through the end of the plunger rod for the priming handle:
Use your threaded rod, 3/4'' nylon spacers, and acorn nuts to build the priming handle:
The final step for the plunger rod is to make the front spring spacer. Its purpose is to prevent the front of the spring from hooking onto the plunger head and wrecking the seal. My solution is simple and elegant--what I always strive for! Lightly sand down the corners of the plunger rod in front of the catch notch:
Take your 1/2'' ID, 5/8'' OD polycarbonate (or CPVC) and cut out a 3/4'' segment. Drill and tap through the rear of the segment and the corresponding spot on the plunger rod:
Here you can see it in action, secured with a 1/4'' set screw:
Now is when this mod gets extremely hairy. How hairy? I'm talking Bigfoot and Chewbacca having a kid and that kid fucking Osama bin Laden. Yeah, prepare for some pain. The [k26] will wreak havoc on the rear section of the blaster of there isn't something blocking it. I decided to design my own rear spring stop out of 1/8'' polycarbonate--check it out!
This piece does not need to be glued into place and slides onto the plunger rod right in front of the trigger catch. Here is my fabrication process:
You will need to round the edges--look closely at the shell to see how the piece needs to be shaped. To make the square hole, I used a thin drill bit for my Dremel. Here you can see how the spring stop snaps into place:
The trigger catch will also need to be fabricated, since the stock catch is too tall to work with an aftermarket plunger rod. Here are the schematics for this one:
Like the spring stop, I first scrolled out the outline then later drilled a 3/8'' hole and expanded it with the Dremel:
Drill and tap the top center of the catch and insert a 3/8'' set screw:
Comparison with stock catch:
Whew! Now that that thing is done, all that is left is to mod the trigger. Cut a 5/16'' x 3/8'' piece of 1/4'' PVC and glue it to the trigger like so:
You may need to Dremel the trigger and/or the bottom of the catch to get the blaster to catch and fire, so test test test! Once you're satisfied with the fit, it's finally time to assemble the full plunger rod! Slide on the catch, spring stop, spring spacer, 4 1/4'' [k26] spring, and plunger head:
Time to put everything back into place, including the old LED! Yes, I found a spot above the old light housing that the LED can chill in to illuminate the plunger tube. I forgot to include the secondary trigger in the picture.
Close up the shell and screw on your 4 Keps nuts to secure the plunger tube to the shell. Make sure they aren't on too tight. Isn't she a thing of beauty?
Here a shot of the illumination:
Full compression of the [k26] spring after priming:
It took a long time, but the end result was worth the pain. This little pistol is now truly "Elite" in every sense of the word--I may just have to make it its own personal slide breech. It shoots extremely hard--harder than some of my rifles, in fact! Have a look:
This was accomplished with my new 6'' slide breech and shitty beige Hot Rod darts--something I'm very perplexed about. To be honest, I find this velocity to be a little low--the reason I say this is because I don't think the rubber grommet is an optimal plunger head in any respect. It seals very well, but requires an ass-ton of lube and creates a lot of friction with the plunger tube walls. In addition, it falls victim to vacuum loading problems and takes up quite a bit of real estate. In the future, I will no longer use this type of plunger head and I may even swap mine out for a tradition washer sandwich, which is superior in every way.
In any case, I'm very happy with the outcome of this mod, and my segue into homemades continues. This is the first time I've ever worked with Delrin, and I can safely say that I'm never going back to Nylon. Stay tuned for more goodies
Hope you guys enjoyed this write-up!
P.S. Nylon sucks balls.
It seems like the Firestrike is a pretty popular new blaster nowadays and a semi-worthy replacement for the Nite Finder. A few weeks ago I decided that I wasn't showing pistols enough love, so I decide to take one to the absolute max. This mod is one of my finest to date, and I went through a lot of trouble to get this thing functional. Here are some of its wonderful properties:
- 1 1/4'' polycarbonate plunger tube
- Delrin plunger rod
- 4 1/4'' [k26] at full compression
- 1 1/8'' rubber grommet seal
- Custom front spring spacer
- Custom rear spring blocker
- Custom trigger catch
- 1 1/4'' diameter polycarbonate tubing
- 1/2'' PVC coupler
- 1/4'' PVC sheet
- 3/8'' Delrin rod
- 1'' 6-32 pan-head screw
- #6 washer
- 3/4'' fender washer
- 1'' fender washer
- 1 1/8'' O.D. rubber grommet
- 1/4'' polycarbonate sheet
- 1/8'' polycarbonate sheet
- 3'' 6-32 threaded rod x2
- 3/4'' length, 3/8'' thickness 6-32 nylon spacers x2
- 6-32 nylon acorn nut x2
- PVC/ABS solvent
- 1/8'' natural gum foam
- 1/2'' I.D., 5/8'' O.D. polycarbonate tubing or CPVC
- 1/4'' 6-32 set screw
- 3/8'' 6-32set screw x3
- 1/2'' 6-32 set screw x2
- 6-32 Keps (K-lock) nut x4
- Replacement catch spring
- [k26] mainspring
- Scroll saw
- Drill or drill press
- 6-32 tap
- 3/4'' hole saw
Start by gutting that bitch:
Undo the gray tabs holding the two halves together to separate the shell:
Now Dremel off the part the houses the light unit. Do it cleanly, as you will be reusing it!
Here are the pieces you will need from the light unit:
Snap the shell halves back together:
Now to cover the gaps in the shell--chop down the two striped pieces from the light unit like so:
Then use the PVC/ABS solvent to weld it to both halves of the shell. Notice how I lined up the stripes--yes I am OCD like that sometimes!
Trim down the other two pieces:
At this point it would behoove you to cut the plunger tube. 6'' is the length I went with--just long enough to keep the pistol compact:
Now for one of the most time-consuming parts of the mod--Dremeling the shell down to the fit the plunger tube. Use the plunger tube to constantly test the fit. The part right in front of the round section with the Nerf logo gets Dremeled so thin that I just cleared it out to look like an hourglass on both sides. One tip I can provide is to look straight down the front of the shell and look for a perfect U-shape all the way back to the rear of the shell.
At this point let's tackle the plunger tube. Cut down a 1/2'' PVC coupler and leave enough room for a 6-32 threaded rod to pass through:
Use the PVC/ABS solvent to permanently weld the coupler into the end of the plunger tube. As it turns out, the fit is perfect! Use a lot of solvent, as the seal must be airtight. When the solvent cures after a day, drill through the plunger tube with a 7/64'' drill bit and tap it with the 6-32 tap:
Insert the 6-32 threaded rod through the plunger tube. I used two hex nuts and tightened them together. Then I used a wrench on the rear nut and threaded it through:
Before the next step, you will need to drill some holes in the shell. The purpose of the holes is the support the force of the plunger rod, as you will see later. Here is where I drilled my holes--they are perfectly in line with the middle of the plunger tube:
You will now need to fabricate the rear plunger tube supports. They will be made from 1/4'' polycarbonate and follow this schematic:
Here they are!
Now take plunger tube and put it into place and close the shell. Make a mark on both sides through the rear hole on both side to designate a spot of importance. Then take your polycarbonate pieces and solvent weld them into place:
When the solvent cures, put the plunger tube back in the shell and close it up. Make two marks just like before--through the back holes. Drill and tap through the marks you made with the 7/64'' drill bit and 6-32 tap:
I forgot to take a picture of it, but you should insert a 1/2'' set screw into each of the holes you just made. Make sure that they don't protrude into the plunger tube or the spring will get snagged! The final step for the plunger is to cut yourself some plunger padding and insert it down behind the 1/2'' PVC coupler:
Next up is the plunger rod. Take your 3/4'' hole saw and cut a circle out of your 1/4'' PVC sheet. This will serve as a spacer that sits inside the rubber grommet:
Drill a 9/64'' hole right through the middle:
DO NOT POST! THIS WILL BE A TOTAL OF 2 POSTS!
What's the composition? I don't deny that there are legit hard solders out there, but it's important note exactly what you used if others are to use this as a guide.
Sn - 94%
Ag - 6%
Recommended Joint Clearance:
B32 Grade Sn95
I went the soft solder route, since it was incredibly cheap. This type of solder is mainly used for high temperature, high reliability interconnect applications, and is more than enough for a [k26] as indicated by the tensile strength. Hard solder isn't the only solder that can handle a lot of stress!
Which isn't soldering.
Look at all the filler metals listed, and then look at solder. It's made of lead/tin, usually. He says he's using silver solder, which usually contains maybe 3% silver.
Solder requires more of a mechanical connection/joint for it to be anything close to trustworthy for putting pressure on.
From the product description of the silver solder I used:
"Five times stronger than ordinary solder with tensile strength of 10,000-25,000 pounds per square inch. Will stretch under high pressure, but not break under constant stress and is vibration-resistant."
For comparison, J.B. Weld has a tensile strength of 3960 psi and polycarbonate has a tensile strength of 8,000 to 16,000 psi.
@Kronos: Correct. Electrical solder for wires usually has a rosin core, meaning the flux is built into the solder itself. For this application you want the flux to be separate in order to designate the area you want the solder to stick to.
It surprises me a bit, but I've encountered some push back and fear when I have suggested soldering in some of the mods I've done. I had a nut soldered to a brass breech in front of a pas. As the pas was primed an attached bar would also open the breech to accept a chambered round from a clip and then close it again as the handle was returned to the forward position. I eventually abandoned it due to clip stability issues, but the breech - and the soldered attachment was solid.
The only worry I see is that the smaller surface area might tend to bend or distort the brass tube as it's placed under load of the [k26]. It's still pretty early on, but after you get a few hundred rounds through it would you mind posting an update about durability? That really does look like a good long term option though. And like you said - that soldered joint is stronger than the materials it's joined to.
Another thought - copper is insanely expensive. Are brass square tubes of that size available? Perhaps a square tube can be soldered in place and then back filled with epoxy or epoxy putty? There might be some loss to durability, but it would be cheaper. A solid steel bar stock might also be more economical.
I see what you're saying about the brass distorting--I highly doubt it will bend, but I'll post an update after warring with the LS.
As far as replacements for copper, I was unable to find anything cheaper on Mcmaster than the rod I used. Initially I wanted to just stick to brass, but K&S only makes hollow brass tubing in the desired size and I didn't want to risk the integrity of the nub. Solid steel would definitely work, but would be much harder to machine.
This is a pretty cool mod. Good job. I know of a few other users that did a metal welded nub, though no one actually took the time to do a write up.
However I doubt your claims of 300fps. I'd like to know exactly what you did. I know it is possible using certain setups, none of which would be war usable.
Thanks for the feedback! Check out the link to my blog to see exactly what I did.
Sup lady and gentlemen,
This little orange piece has been the bane of my existence since I first decided to make an Angel Breech for my Longshot. For those of you that don't know, this little orange guy is the attachment point between the bolt sled and breech--the #1 point of failure. Pretty much every brass breech mod that I've read calls for gluing this piece to your brass breech. I have tried many types of epoxy, including the one from the original breech created by ForsakenAngel24, but none of them have had enough strength to withstand my [k26] spring. In typical T da B fashion, I set out to solve this annoyance once and for all. This time, it involves fire!
This mod was actually influenced by the RC car modding community. They use K&S brass tubing to make their own homemade front bumpers, Nerf bars (hehe), etc. I did my research on soldering, brazing, and welding in addition to watching Youtube clips of people joining metals to prepare for this mod. Here is what you guys will be needing to make a bond that can withstand the [k26]:
Top left: Butane torch that can produce a flame reaching 2500 degrees Fahrenheit! This will be the heat source used to prepare the metals for joining. I went with the Blazer Stingray GB4001 and I'm very pleased with it.
Top center: Stay-Brite Silver Solder that will be used to fill in the spaces between the two metals to be joined. It is composed of a few metals, and the silver allows the joint to be stronger than the actual metals themselves!
Top right: Stay-Clean Liquid Flux--really poisonous stuff. However, it is extremely necessary for soldering since it cleans the surfaces of all oxides and causes the solder to stick.
Bottom: 3/8'' x 3/8'' x 12'' copper rod (89275K461)
You will also need a Dremel with a cylindrical grinding bit, a drill press, and cutting oil for this job.
Cut a 19/32'' length piece off of your square copper rod and grind down one end of it with a cylindrical grinding bit on the Dremel.
Bust out the drill press and drill a 1/8'' hole 1/8'' from the flat side of the piece. Use cutting oil to lubricate the drill bit and prevent overheating. You should also grind down the top of the nub at this point to fit the bolt sled, but I forgot and did it later.
Now build yourself some sort of jig to hold everything in place. I also ended up wrapping a rag soaked in water around the end with the plunger tube to prevent melting. Ideally you would do this before gluing on the bottom of the old breech. Make some marks to designate where you want the nub to go and then rough up both surfaces and clean them with rubbing alcohol. Apply flux to the bottom of the copper nub and carefully put it into place. If you ground it down properly, it won't fall off. Now hit it with the flame from all sides for a minute, then touch the solder to the base of the nub and solder should flow into place due to "capillary action."
Finished product--not the prettiest but it gets the job done! Clean up any solder with the Dremel.
Here are some glamor shots with the new nub in place:
So there you have it! The greatest problem with the Angel Breech has finally been solved. The fact is, metal is just too slippery to be held with epoxy, even after roughing the bejeezus out of it. After soldering things into place, my breech will never be breaking in that spot ever again. A silver solder joint is actually stronger than the metals you are joining! Pretty legit, eh? If you guys want to read the full write-up for my Longshot, check it out at my blog. I modified SgNerf's design and managed to squeeze 300 fps out of it!
I hope you guys enjoyed this original write-up.
~T da B