36 replies to this topic

[Naturalman7]

If someone knows how to share flickr photos without having the photo name or name of photographer appear so I can save room, that'd be great.

Intro
The first experiment I did with making a Rainbow type blaster was incredibly successful. Since then, I've made numerous Rainbow style blasters and I still haven't shared any of my experiences – now here they are. The rainbow refers to the unique catch mechanism. It was so named because it was originally designed by the ‘Rainbow Clan’. It utilizes two polycarbonate disks sandwiching a moving catch plate that catches in a notch cut into the plunger rod. The catch, like most of the work done on this blaster, requires use of tools not typically available to the average Nerfer. Cutting of the polycarbonate circles, the square holes in the centers of the disks, and drilling precise holes are all necessary in this build. A hole-saw, scroll saw, drill press, sanding tools, and skill with the aforementioned are all highly recommended and completing this build without these is extremely difficult, if not impossible – if you want to try some other techniques than the ones in this guide that builds the machined catch pieces that accomplishes similar goals with less tools, then try here: Handmade Rainbowpump Variant. It just takes more time and effort if you don’t have tools.



I'll add/edit/optimize the photos and provide links to references and other sources later. There should be enough info...for now.


Overview and Cost
This is a simple and basic blaster that has been commissioned in the past, but I haven’t seen any sort of write up for it. I’ve seen a lot of NoM’s commissioned Rainbow Pistols, and they all look super nice. This write up won’t address counter sunk black oxide screws, staining wood or fancy engravings, but will just be the basics. Perhaps, I’ll add a section later on customization if I do any fancy experiments.

This write up places the handle half an inch from the rear of the PVC main body of the blaster. I personally liked this look better, but relocating the handle further back on the blaster can reduce cost and size of the blaster.


The blaster seen in this write up cost $16.82. Omitting the optional nylon washers would reduce the cost ~$0.38. An opaque blaster would bring the cost down a further $3.00. Changing the seal piece would reduce the price an additional $4.00. I anticipate the cheapest this blaster could be produced is $9.50.

The cost of materials to build one of these blasters is $138.11. This is not the cheapest possible. This is likely the best raw materials cost to produce the cheapest per blaster cost.


Tools
Required
• Drill
• Scroll-saw
• Screw drivers – ph2
• Tapping sets (#6-32, #8-32 optional)
• Sand paper
• Hacksaw
• 7/64” drill bit for #6-32 pilot hole
• 5/32” hole for #6 pass through screw holes
• Drill bit that your screw driver can fit through (5/16”)
• 9/64” drill bit for #8 pass through
Recommended
• Drill press
• Table saw
• Table Belt Sanding
• Hole saw – 1-3/8” or 1.5”


Materials
• 2x #6 x 3/8" Washers
• #6-32 Nylon Insert Lock Nut
• 12x #6-32 x 1/2" Machine Screws
• #6-32 x 1-1/4" Machine Screw
• 3x #6-32 x 3/4" Machine Screws
• 2x #6-32 x 3/8" Machine Screws
• #8-32 Nylon Insert Lock Nut
• #8-32 x 1.25" Machine Screw
• #8-32 x 3" Machine Screw or a 2.5” screw if you can find one
• 14 sq in 1 x 8 x 2 Poplar Board
• 1”- ½” PVC bushing
• 3/16" x 1-1/4" Fender Washer
• 2x 3/8" x 3/16" x 1" Nylon Spacers
• 8.5”x Black Delrin® Acetal Resin Rectangular Bar, 3/8" Thick x 3/8" Width
• Catch spring
• 5”x [k25] Compression Spring, Spring-Tempered Steel, 11.0" Long,.968" OD, .08" Wire
• 6.75 sq in Impact-Resistant Polycarbonate Sheet, 1/8" Thick, Clear
• 6 sq in Polycarbonate Sheet 1/4" Thick, Clear
• 9”x Std-Wall (Schedule 40) Clear PVC Unthrd Pipe 1-1/4" Pipe Size
• Stretch-Fit Rotary-Shaft Ring Seal 1" Shaft Diameter
Optional
• 8x Nylon General Purpose Flat Washer, NO. 6 Screw Sz, .32" OD, .05"-.07" Thk


Important note: The reason I did not include a part number or anything for the catch spring was because you can use any spring you want. I used a small spring that I took from a different Nerf blaster. If you don't have any springs just lying around, you can use a spring from a pen if you can cut it down. It should be pretty easy. I've never purchased springs from McMaster for this purpose before, but I imagine you can find them.

 

 

Templates
Here are some different versions of the handle and the catch pieces. idw wasn't playing nice and wouldn't let me annotate the threads properly.
PDF Version
IDW Version



Procedure

Machined Pieces
You can either machine each piece before starting, or machine each as you go. I prefer to machine each as I go, unless mass producing any piece. But for clarity’s sake, I’ll just have you do it now until you’re more familiar with how to make each piece.

Apply the sticker templates to the polycarbonate on the indicated thicknesses. There are protective sheets on the polycarbonate. Glue or, if printed on adhesive backed paper, stick the templates on the polycarbonate. The rectangle side plates are the only pieces that need to be 1/8” thick. I’ve theorized using the 1/8” thick polycarbonate for the rear catch circle which may be possible. All other pieces are ¼” thick polycarbonate. The rectangle handle piece, trigger, and main handle piece are all for 1” wood – with a ¾” nominal thickness. You could look into what NoM has done with his handles and use polycarbonate for the trigger, but I’ll keep this guide basic.

The easiest way to machine the pieces is to first drill all the holes on the faces of the pieces. Drill the holes as marked. Then, use a table saw to cut the square rectangles, cut the front wood handle piece, and cut the wood main handle piece. The wood trigger is easiest to cut on a scroll saw. The catch pieces, circles and catch plate, are also easiest to do on a scroll saw. However, I’ve recently found using a hole-saw and turning it down on a lathe is easiest for the circles.

Each piece has little quarks that I’ve come across.

Side Plates
Drill and cut the side plates out of 1/8” polycarbonate. ¼” thick polycarbonate is useable and would be an easy option due to ¼” polycarbonate being also required for other parts of the blaster. The easiest way to machine these pieces is to cut them on a table saw and drill the holes with a drill press. Either drill all holes on the handle side plates 5/32”, or drill the middle hole 7/64” and tap for #6-32. If tapped, this allows the trigger screw to tighten or loosen on the trigger. I find that, depending on how the handle wood pieces are sanded, the side plates could end up being too tight on the trigger to allow it to rotate freely. This can be resolved by sanding the trigger smaller or increasing the gap between the side plates by adjusting the trigger screw. You’ll want to sand all the edges and corners down so that it’s comfortable – more on this later.


Handle Pieces
Drill and cut the forward handle piece, trigger, and handle. It is often easier to drill the pieces before cutting, because there’s more material to hold onto while drilling. However, the order isn’t important. All the holes are 7/64” except for the trigger which is a pass through for a #6 screw - 5/32”. The forward piece and handle are easiest done on a table saw and the trigger is easiest to cut out on a scroll saw. When the main handle is cut, drill the two holes on top. The holes in top of the main handle are easiest done in a drill press vise where the holes will be straight and the base of the handle will be flush. These, as well as all the holes drilled, should be centered and straight. Otherwise, your handle or other pieces could be ridiculously crooked and may cause friction, the screws to not align, or other problems. When the pieces are drilled and cut, sand them down. Smooth down edges and sand the trigger and handle so they are comfortable to use. I use Ryan’s original templates, but I remade them with more detailed markings - like center lines for example.


Only one of the top 7/64” holes in the forward wood handle piece is needed. The other hole, if used, interferes with the function of the blaster. Modification of some of the pieces may remove redundancy, but the templates were borrowed from Ryan and the parts I’ve mass produced are also interchangeable with my Rainbow Pump blasters. I will add this to the customization section.

The trigger’s flat top prevents the trigger from over traveling forwards. If the hole is drilled too high or the top cut is too low, than the trigger will be allowed to move forwards, which may be a minor undesired feature.

Catch Circles

The catch circles are easiest to first drill the two 7/64” holes in each circle, then to cut them out with a hole-saw, and then to finally lathe them down so they fit in 1.25” PVC. However, if you’d like the practice or are good with a scroll saw, than it would be faster to simply attempt to cut the circles with it. If done with a scroll saw, it’s easier to drill a pass through hole for the scroll saw blade in the center of circles to cut out the square holes. I like the perfect roundness of lathes, but a scroll saw is faster and, with skill, is just as easy to make round. However, if cut with a scroll saw, it may be necessary to sand the edges down so that it fits smoothly into PVC.


The catch plate is easiest to just cut out on a scroll saw after drilling a center hole. After all the pieces are drilled and cut, thread a scroll saw blade through the pieces and cut the square holes. I find it’s easiest to start the cuts diagonal first, and then square out the holes. Here are some pictures to clarify.

Drill the center hole.


Cut diagonally.


Shave out the inside of the squares.


Then clean it up.


You’ll want to make sure that all the pieces are smooth and sanded well. They need to be able to slide across each other freely.

Also, while making each piece of the catch, you’ll want to make sure that the square holes fit the Delrin rod and that at each step, the catch fits in the PVC body or you’ll have to sand it down again.


Plunger Head Circle
The easiest piece to machine is the circle of polycarbonate for the front of the plunger head. I find that this piece should be as wide as possible, but still allow the plunger head to fit into the PVC plunger tube. More on this later.




Handle

Handle Assembly
After the pieces are cut and all the holes are drilled, assemble the handle. Assemble the handle with eight #6-32 x ½” screws. Tighten well – I like my handles to not have any wiggle. I use nylon washers because I think they look nice and you wind up with a lot of extra washers from making a +bow. Omitting these washers reduces the cost of the blaster by ~$0.38. However, I’ve also noticed that the handle may be thinner than the 1” that these two screws would require and that the washers give a larger margin of error in the thickness of the wood or length of the screws. This is also another reason one may want to use ¼” thick side plates instead of 1/8”.


Catch

Cut
I know I’ve said some of this before, but here’s where it’s important.

Cut, drill and tap all the catch pieces. It’s easier to drill the two 7/64” holes in the catch circles before cutting anything out. Cutting the pieces out is pretty self-explanatory, but it took me a few tries to cut circles and such perfectly on a scroll saw. I’ve found that the easiest way to make the catch circles was to find a hole-saw and cut the templates out, then widdle it down on a lathe until it fit easily in the main body. The catch assembly and pieces should fit in the 1.25” PVC freely. One of the common pitfalls is machining the catch pieces. There’s quite a bit of margin of error, but the process can be made easier through a little bit of practice and technique. Just go slow and steady is the key. I find the easiest way to cut the square holes are to thread the blade through the center hole of the hole saw, cut diagonally across the squares, then ‘carve’ out the rest of the hole. Continuously test fit the 3/8” square Delrin rod into the catch pieces. For the catch plate, drill a pass through hole for the scroll saw blade, then cut the square hole.


Drill and Tap
Drill a 7/64” hole centered through the bottom of the catch plate and tap it for #6-32. Also tap the holes in the catch circles #6-32. Make sure the holes in the catch circles are straight, otherwise, if you’ve originally made the circles perfectly sized, the misaligned holes could cause the circles to no longer fit. With all the work done on the catch, debur and sand all the edges and holes in the catch pieces so they are smooth.


When I had originally printed out templates, they included diagonal holes for the screws to attach the catch to the main body. You can either drill and tap these in one of the catch circles, or simply wait to drill and tap them later – which would likely be easier, but I’ve done it successfully with either way.


Assemble
With the catch plate as a guide, assemble the catch with two #6-32 x ¾” screws with a .25" gap between the circles. The catch plate should slide freely in between the circles.


On the first Rainbow’s I made, I simply drilled the templates, cut the circles, and rounded them out on a table belt sander instead of a lathe. Using a table sander gave the advantage of being able to easily sand the catch circles as a whole assembled piece, if needed.

When the catch is assembled, it should still slide into the PVC easily. If the holes are misaligned and the catch is lopsided at all, hitting it with a touch of the sander can straighten it out to fit in the PVC again.



Main Body

Measuring and Marking
Figure out what spring you want to use. You’ll need to adjust the design to whatever it is you’re using. Take into account the length and pre-compression. The spring will change the length of PVC, the length of plunger rod, position of catch and subsequently the handle. I was thinking about creating some sort of program to calculate all the recommended dimensions based on inputting different spring and draw preferences.

I’ll be using 5” of [k25] with 0.5” of pre-compression.

I like any words on the PVC to be on the bottom of the blaster. Use a three sided ruler to mark the bottom. Then, use a marking rig to measure the body in eighths and extend these marks.


This write up places the handle half an inch from the rear of the PVC main body of the blaster. Make a mark there on the bottom of the blaster.

Place the handle on the mark and mark on the PVC where the holes in the wooden handle pieces are and where the trigger lines up.


With the marking jig rig again, extend/copy the marks of the three holes to the top of the handle.

Drilling
Drill the marks for the handle on the bottom 7/64” and make sure the handle still lines up with those holes. These holes are the two closest to the back and the one closest to the front. Tap each of the 7/64” holes in the bottom of the blaster #6-32.


Then, drill the mark for the trigger 5/32”.

Flip the body over and drill the three holes on the top of the blaster to fit a screwdriver through. The position of these holes should be marked on the blaster and should be mirrored from where the holes for the handle are. These wider holes are for attaching the handle. I used a 7/16” bit, but a smaller hole would work if your screw driver is smaller.



Catch
Take the catch, which should fit into the body, insert it with the threaded side of the screws to the front. If you’re wondering, the flat side of the catch will act as the rear spring rest.

Align the catch plate over the 5/32” pass through hole in the bottom.

Assemble the catch spring into the blaster and tighten it down so the catch stays in position.


Then, with a 7/64” bit, drill all the way through the body and catch circle on the diagonal sides. In order to keep the catch centered properly when drilling the holes, I like to hold the position of the catch with small drill bits.


With the holes drilled, now here there are a few choices. Remove the catch and tap the PVC and polycarbonate. If you did not drill and tap the catch circle before, you can remove the catch from the body and tap the holes. Or, simply tap the holes through the catch. Either way, put threads into the PVC and catch. You will need to push the catch out of the PVC with something long and skinny.


Attach the catch with four #6 x 1/2” machine screws.

Make sure that the affixed catch can fit the 3/8” Delrin rod freely and without friction. This shouldn’t be an issue if you test fit as you go and make sure you drill and tap all the holes properly.

At this point, you can remove any sharpie marks with alcohol.



Attaching Handle
Attach the handle with three #6 x ¾” machine screws.

It’s easiest to do this by holding the blaster upside down and starting the screws partially into the body.


When the screws are held into the body, I like to press the handle against the body and tighten the front most screw first, then the rear most, and finally the middle.


Make sure that the trigger is oriented properly, and not angled when you attach the handle.



Plunger Rod
At this point, I like to make the plunger rod next. This will determine the draw length and placement of catch.

Cut the section of 3/8” square Delrin to length – 8.5” is what I used. The length mostly effects how much finger room you have to grip the nylon pull back handles.

Then, mark the center of one end of the Delrin – which will be called the plunger rod (PR) from now on.


Drill two holes into the plunger rod. One in the center of the end of the rod for the plunger head, and one for the pullback handles.


I like to use a #8 sized screw for the front of the plunger (or plunger head/PH) because its wider diameter helps keep the PH centered. Drill a 9/64” pilot hole approximately one inch deep into the Delrin and tap it #8-32. Keeping the hole drilled and tapped centered will assist in making the air seal as perfect as possible.


Drill the second hole 11/64” pass through hole for a #8 screw centered on the rear end of the Delrin rod.

Plunger Head & Catch Notch

Create another ¼” polycarbonate disk that fits onto the top of the rotary shaft ring seal.

Then, assemble the plunger head as pictured. A 1.25” x .25” metal fender washer acts as the spring rest and supports the skirt seal, the rotary shaft ring seal creates the air seal, the small section (11/64”) of 1” OD 7/8” ID tubing keeps the skirt seal from buckling inward on itself and ruining the air seal, and the polycarbonate disks in front squishes the skirt seal which seals the two holes in the top of the skirt and compresses the skirt which flares it outward, which helps the seal. I’ve found that making this piece as perfect as possible goes a long way to making the seal perfect. The front polycarbonate disk flares the seal outward and presses it into the walls of the PVC body. Without the tubing piece, the skirt seal sometimes buckles inwards and causes one side of the skirt to not seal probably. With a proper polycarb disk on top combined with a tubing piece of the right height, the seal is perfect and low friction. If the plunger head when lubricated has too much friction in the PVC, take down the OD of the polycarb disk slightly and retest fit it. This method seems to create a 100% seal perfectly, every time.


Test fit this whole thing by lubing up the seal and inserting this plunger rod into the plunger tube, from the front. It should be a fairly tight fit, but should slide.


Test the compression of your spring and gauge where the catch notch in the rod needs to be.

I cut my notch for a 5” long [k26] with ½” pre-compression 1.75” from the plunger head. Keep in mind the thickness of the catch plate and catch circles. You’ll have to account for the added ½” in your measurements.

This notch is cut too deep.

With the spring and plunger rod properly fit in the body. Place the nylon spacers, #8-32 x 3” machine screw, and #8-32 locknut into the hole of the plunger rod. The machine screw will be too long, so hacksaw it down to a better size. Unless you can find a #8-32 x 2.5” screw, but I’ve been unsuccessful.


Front Bushing
The last, and arguably the most important step of a Nerf blaster is the front seal. There are a few different ways to create this seal. One involves plumber’s goop and tape of some sort.

Either sand down the lip of the bushing or have it stick out.


Wrap the base of the bushing in packing tape (or electrical tape, but I’ve found packing tape to be better).


Apply goop around the bushing and insert it into the front of the PVC. Apply any excess goop that leaks out around the seam of the front to ensure it seals properly


On the top and the bottom, measure ½” from the front of the bushing and drill two holes into the bushing 3/8” deep. I like to put the two screws for the front bushing on the top and bottom because if the screws were placed on the sides and the blaster down, the heads of the screws can scratch a smooth surface if the screw heads are not smooth.



Screw in two #6-32 x 3/8” machine screws to attach the front bushing. I find two to be enough. One would be too little, and I haven’t noticed that three provides any benefits.

By drilling the holes exactly to depth and not tapping them, it allows the fit of the screw in the hole to be tight enough that it helps the bushing to seal around the screw and it also creates slight ‘squishing’ of the bushing that increases friction in the bushing which can keep ½” PVC in the bushing better.

The second method, and the method I am still not sure how to perfect, involves just sealing and attaching the bushing with friction. Basically, it’s just hammering the bushing into the front of the PVC. Wrapping the bushing in tape can help keep it centered. The friction of the lip on the bushing creates a perfect seal with the PVC and the lip is wide enough to keep the bushing centered. However, I’ve found that, depending on the exact dimensions of the PVC and bushing, the force caused by the difference in size can actually cause the PVC to crack and ruin the blaster. The ID of the PVC is 1.335” and the OD of the bushing is 1.375”. I’ve lathed down the bushing to 1.365”, but there wasn’t enough friction to keep the bushing in place when pushing on a wye or barrel. However, it didn’t crack after several days, so there is room for a wider bushing that could work. The bushing sealed, but did not stay in place. Opaque PVC has a wider ID than clear, so that also causes a difference. Some pictures of the process:


After the bushing is dry and sealed, the blaster is done.



Maintenance
If excess dirt gets in the plunger tube/pressure chamber/main body/PVC, the front bushing can be unscrewed and removed by hammering or banging the rear of the plunger rod. I’ve done this several times without breaking the plunger rod and having seen any adverse effects. With the bushing removed, you can unscrew the pullback handles then remove the plunger and do whatever cleaning or replacement/repair you need.


Performance
I’ve found that my Rainbow Pistol shoots amazingly well. Much better than I originally thought it would. I used it at ‘geddon and loved it and have used it in local wars to great effect. It’s a great loaner blaster - powerful, accurate, easy to prime, small, and, coupled with a loading mechanism, decent rate of fire. It’s comparable to a panther, but slightly bigger, less range, and is easier to prime which gives it a greater RoF.

Barrel
I found the optimal barrel length (at least with my darts and a fairly tight batch of CPVC) is ~8.5” and can achieve ranges in the 80s consistently. In my ventures, I’ve found three different fits of CPVC. All three have different ID’s and I’ve find the tighter the fit, the better. I hammer the CPVC barrels into sections of ½” PVC. The fit, in the right brands of ½” PVC, is such that it stays together and seals with no further effort. One batch of the CPVC had an OD of less than 5/8” and required finding a batch of SCH40 ½” PVC that had a slightly smaller ID than regular and I had to CPVC/PVC cement the two together. If glued well, the two brands seal despite a large clearance.


Speed Loader
I like old fashioned speed loaders. It reminds me of the time when most people used simple speed loaders all the time. It’s my favorite method of loading pistols and I’ve used them a lot on CPVC couplered Nitefinder pistols.

The easiest way is simply taking 1.5” sections of SCH40 PVC and mallet-ing 8.5” sections of CPVC into them. The fit of these brands is such that they stay together. I then PVC/CPVC cemented them together and held them in a vise until they dried. The bond was quite strong, but to be sure, I then wrapped it in stylish tape.

RSCB
These are a fairly dated technology, but this was the first real RSCB I’ve made so I thought I’d share. Instead of just sticking ½” PVC fittings and pipes into each other, I stuck a variety of different pipes into each other to decrease overall size and dead space. I took a ¾” length of ½” SCH40 PVC, hammered it in a 1.25” length of ½” CPVC, added a CPVC tee, glued it into a ½” PVC tee, added a barrel and loading tube. I cemented in all the fittings and CPVC sections.

To adapt the barrel to load from the RSCB, I took a ¾” countersink and reamed the CPVC/PVC. I then took a large step less drill bit to create a smoother loading for the dart. I’ve found this is necessary because the dart seals better and loads much more reliably.


You may need to modify the design to stop darts from getting stuck in the tee, but I've found that it happens rarely enough that it's acceptable - but it does happen.


Slide Breech
Drill the ID of a section of ½” PVC out to 5/8”. The easiest way I’ve found is with a lathe and drill bit. I’ve used a steady hand and a 5/8” spade bit effectively as well. Cut a rectangle in the PVC. The size of this cutout section depends on the size of darts you intend to use. I start the cut by, obviously, marking and measuring it out first. I put the rectangle ~1” from the end of the PVC. This gives room to insert the breech into the bushing and a little extra so that it doesn’t feel too crowded. You’ll have to account for this extra distance when cutting the slot.

Cut the rectangle to the shape and size you want. I use a Dremel for breeches. There’s not another way I can think of to cut the slot.

I add a locking lug to keep the breech from opening due to air pressure from a tight dart fit.

I add this by cutting a semicircular in the bottom of the slot in the ½” PVC with a Dremel or drilling it with a bit.

I then drill a small hole for a small screw in the CPVC barrel. I close the breech and mark where the lug hole is. I then take a small nylon spacer and attach it with a small screw. It’s hard to find a perfect spacer and a perfect length and size of screw, just make sure the screw doesn’t stick too far into the CPVC and a dart can slide in. A breech can be considered either complex enough to need a write up of its own, and I’m sure there may be one, or several, write ups already. Or it can be simple enough to not need one and I’ll assume the latter.

One thing you should do is ream the CPVC to make it much easier to load and it makes a big difference. The darts will slip into the CPVC and angle right into the breech instead of potentially getting caught on a square edge.

Hopper
I’ve never tried to hoppered a RBPistol before. I imagine it would be possible with a low capacity hopper and will update this section when I try.

Edited by Naturalman7, 01 November 2016 - 10:41 PM.

[Thorn]

Great writeup! Very clear and detailed. I've been waiting for someone to make a RB pistol writeup for a while now. I would suggest that you cut your catch notches straight down and then horizontal for at least a 1/4 inch, the back up at a 45 degree angle. That way the catch piece sits flush in the catch notch, and you don't have to cut it as deep. Also, If you made your rscb with a cpvc fittings and used copper instead of clear pvc, it would reduce deadspace and eliminate the problem of the darts falling in the tee. Are you submitting this in the homemades contest?

[Naturalman7]

Great writeup! Very clear and detailed. I've been waiting for someone to make a RB pistol writeup for a while now. I would suggest that you cut your catch notches straight down and then horizontal for at least a 1/4 inch, the back up at a 45 degree angle. That way the catch piece sits flush in the catch notch, and you don't have to cut it as deep. Also, If you made your rscb with a cpvc fittings and used copper instead of clear pvc, it would reduce deadspace and eliminate the problem of the darts falling in the tee. Are you submitting this in the homemades contest?

Actually, I do cut my notches just like that, usually. This notch was...done hastily and awhile ago. I am planning on changing that part of the write up eventually. This is actually the exact text I including with this same photo on Facebook: "Don't cut the notch any more than half way through the Delrin. This notch was cut too deep. I like to cut a four sided shape into the notch. Half way down, .25" across, and 45 degrees up. Don't cut your notch like this. It will break. If it does, the solution is below.". I like to use clear loading tubes. I was thinking about putting something in the tee instead - like electrical tape. I was thinking about submitting it, but it's not pump action or as powerful as 'war worthy' homemades.

[F1Nerf]

I've seen many homemades that honestly don't look very good. This, however, looks very nice, & the writeup is very thorough, which I also like. I'd go so far as to say that this looks something NoM himself would make, blaster & writeup. A+ as far as I'm concerned.

[Naturalman7]

I've seen many homemades that honestly don't look very good. This, however, looks very nice, & the writeup is very thorough, which I also like. I'd go so far as to say that this looks something NoM himself would make, blaster & writeup. A+ as far as I'm concerned.

Thanks for that positive review. I'll have to admit, though, that NoM's work is better than mine. I'll include some of his work in the 'customization' section.

I welcome any review, comment, or criticism regardless of how blunt it may be. I feel that improving upon write ups may be just as important and valued as a blaster itself - so I appreciate any and all feedback.

Edited by Naturalman7, 15 July 2014 - 07:54 PM.

[Drev]

Wow, very in-depth and good writeup. I was actually about to make a RBpistol writeup because there wasn't one, but now I don't need to. Anyways, you have really streamlined the process of making one of these which is great and I like the different template options. I also think this would be a good writeup that people should read before making any rainbow because it thoroughly goes over the techniques used in making one. As for the homemades contest, I don't see any reason why you shouldn't submit it. It might not be a war worthy as the other blasters, but this is a very good beginners rainbow and it is a great intro to building rainbows in general. Submitting it won't hurt.

[Naturalman7]

Stuff, and things.

I've found a certain process really makes building a Rainbow simple - only three years late . I guess I'll submit it. I'm working on another RBpump write up and a RBpup as well. Also a RBpac.

[Zorns Lemma]

If you are using the "share on forums / BBCode" feature of Flickr, I'm not sure there is a way to disable the attribution. The best way is to manually delete that stuff as you paste it in.

I just cleaned up your OP in bulk by matching this following regex pattern:

\[url=https\://flic.kr/p/\w*+]\w[^,]*+, on Flickr

and replacing all instances of it with a null character.


The only assumption this pattern makes is that your Flickr image names all start with an alphanumeric character, and do not contain a comma. If your images did in fact contain commas then I would have to replace the very efficient possessive tail pattern [^,]*+, on Flickr with something like .*?, on Flickr which would still fail if any of your image titles contained the phrase ", on Flickr"

[Aeromech]

God that is sexy. I love my rainbow pistol and your method of assembly is really nice; hitherto I have slid in the internal components from the rear with a pre-installed front bushing. I will try this method next time I make one. Very lucid and detailed writeup.

[Naturalman7]

God that is sexy. I love my rainbow pistol and your method of assembly is really nice; hitherto I have slid in the internal components from the rear with a pre-installed front bushing. I will try this method next time I make one. Very lucid and detailed writeup.

Thanks. I love my pistol, too. It would be great if I could figure out the friction fitted front bushing method. It would make a 100% mechanically fastened and sealed blaster that would make dis-assembly and reassembly so easy.

[archangel24]

For either method, especially the second, you could lathe down the bushing so that the OD of the bushing is exactly the ID of the PVC PT. Then to adhere it, use solvent weld and a set screws or a bolt to hold it in. This way, the bushing is chemically bonded to the PVC PT and the bolt/set screws will just help distribute the force and no air is lost. To help with solvent welding, you could lathe some recessed rings into the bushing to make sure there is still some solvent weld between the bushing and PVC PT.
Though it defeats the mechanical aspect of the second method but takes it and combines it with the first to make a stronger product.

This is a method that I used when making a set of commissioned tornadobow internals (though the PT was polycarbonate). It allowed for the bushing to be airtight in the PT as well as making sure that force was distributed better (i.e. a weaker goop bond not being able to take the stress as well). I even tested it out before putting a bolt through and it held up perfectly fine, the bolt was just a formality and insurance/peace of mind.

Edited by archangel24, 16 July 2014 - 02:04 AM.

[Naturalman7]

...to adhere it, use solvent weld...

The thought did cross my mind, but it would make the blaster very difficult to take apart if anything needed replaced. One would have to unscrew the PH from the front and the PH would have to be the last thing removed from the blaster. I'd probably use screws for 'peace of mind' regardless of the method, but goop is the best temporary sealing 'glue' I've found.

[Aeromech]

I believe Captain slug used electrical tape and screws to fasten down his bushings. He was very proud of using no adhesives, (As he should be.)

Here is the writeup. Steps 2 through 8 appear to be relevant.

EDIT: Fixed the link.

Edited by Aeromech, 16 July 2014 - 06:35 PM.

[Naturalman7]

I believe Captain slug used electrical tape and screws to fasten down his bushings.

Very interesting. It's not just the tape and screw that accomplish this though. It's the hammering/malleting of the bushing into the front that I think is important - maybe. There's some sort of magic involved, clearly. The e-tape seals with tube, bushing seals with coupler, and tightening, loosening, and re-tighting of the screws is definitely some sort of magic.

Also, your link is broken. Too much http

[Daniel Beaver]

I have far less reverence for his methods of fastening bushings than you guys seem to have. They wiggled, leaked and cracked.

This writeup is very good - I'll probably link to it instead of my original rainbow writeup in the future.

Edited by Daniel Beaver, 16 July 2014 - 02:58 PM.

[Ryan201821]

Great write-up. The pictures and descriptions of everything are very accurate in my experience of building Rainbows and blasters in general. Lots of helpful information.

I'm actually surprised you can't get this to be hopper-able. Maybe too much barrel? 5" of draw seems like plenty of volume.

We're actually working on basically a 3D printed version of this, and I always thought the priming handle on Rainbow Pistols were awful. I came across these on McMaster and thought they'd be perfect for this application and are pretty cheap. The only problem is I have no idea how to affix them to a square plunger rod. Thoughts? Seems like we're going with a 3D printed priming handle, but the ball knobs would be a lot more convenient.

Also, Ryan’s original guide was incorrect in the parts list and wording of his guide. He said to use ¾” long screws to assemble the handle which are far too long to work. It would work if you used wood with 1” nominal size, but most 1” woods have an actual thickness of ¾”.

This. The wood we used was actually 1" thick. I enjoy the thicker handle. All our 3D printed handle are like this as well. I also recall using 1/4" thick side plates for handles like these, but I've gone through so many variations of handles, I may have used both.

I have far less reverence for his methods of fastening bushings than you guys seem to have. They wiggled, leaked and cracked.

I totes agree with Beaver here. There really isn't any easy way of making something seal in PVC without using some type of adhesive or tape. If you do it like the second option the OP points out, this will usually result in your PT cracking, assuming you're using clear 1 1/4". If you do this with regular 1 1/4" opaque, it fits quite nicely, or is a little loose. I'll usually fill the void with either electrical tape or hot glue. I am absolutely not a fan of Goop as it takes a while to cure, smells bad, and it's more permanent than hot glue. I don't understand why people don't just use hot glue more. It seals well enough for what it's being used for.

Even with 3D printed parts, you still have the same problems, which is why we aim for printing the bushings/redirectpieces a little bit smaller than the tube it's being fit in, then hot glue them in. If you screw up, it's easy to hammer it out, and will seal great if you do it well.

The electrical tape method CaptainSlug used in the +bow's works great initially but the tape gets fucked eventually and what Beaver said happens. This is in my experience after making more plusbows than pretty much everyone.

However, if you do use tubes that are actual sizes (i.e. plusbow PT's), it is possible to buy other tubes that will fit in one another. This may be expensive though, and you still have to reduce down to PVC-sizes.

[Naturalman7]

[lots of good stuff]...

Well, the reason I’ve never successfully hoppered a RBPistol before is that I have never actually tried to hopper one, yet. I'll edit OP to clarify.

I have seen a 'ball knob' blaster CAD mock up on your site. At first glance, it looks fairly awkward/uncomfortable to prime, but it may be personal preference. Would it not be a simple matter of just drilling and tapping the back of the rod and screwing on the knob? (that is if the knob loosening over time wouldn't be an issue). However, a knob would probably be just as much work and cost just as much.

Ah yes. After going through the Rainbowpump Writeup again, it does look thicker than 3/4". I withdraw my previous statement. And you did use 1/4" thick side plates. Nerf handles are typically 1" as well. Moral of the story, use whatever thickness of wood you like, but adjust screw length as necessary. +bow's 'allow' for 3/4" thick handle replacements and SNAPbow's 'use' 3/4" thick handles as well.

Filling the void in the front bushing is done with packing tape to make sure it's centered. I prefer goop and apply it at the very end of building after making sure the rest of the blaster works because it takes a long time to dry. The only real down side I've found with goop is that it takes a long time to dry. The odor isn't very bad and I find that it's just as permanent as hot glue. I've had high temp hot glue melt ABS blaster shells before which is bad and I have had several problems with hot glue in hot weather, specifically left in a sunny car.

[Ryan201821]

I have seen a 'ball knob' blaster CAD mock up on your site. At first glance, it looks fairly awkward/uncomfortable to prime, but it may be personal preference. Would it not be a simple matter of just drilling and tapping the back of the rod and screwing on the knob? (that is if the knob loosening over time wouldn't be an issue). However, a knob would probably be just as much work and cost just as much....

...Filling the void in the front bushing is done with packing tape to make sure it's centered. I prefer goop and apply it at the very end of building after making sure the rest of the blaster works because it takes a long time to dry. The only real down side I've found with goop is that it takes a long time to dry. The odor isn't very bad and I find that it's just as permanent as hot glue. I've had high temp hot glue melt ABS blaster shells before which is bad and I have had several problems with hot glue in hot weather, specifically left in a sunny car.

It is a personal preference when it comes to the priming handle, but also a small safety issue, in my opinion at least. Since the plunger rod flies forward when fired, and the priming handle is fixed to that, the priming handle could potential diddle part of your body when firing. I'm not saying this happens a lot or it's ever happened, but people who don't know wtf they're doing are more prone to this happening to them. Of course it matters more in our case, since we're building blasters with the purpose of selling them to people (both NIC and non), but we try to make everything as moron-friendly as we can. You'd be surprised what non-NIC people try to do when they use a homemade nerf blaster. A ball is pretty much the best thing to get hit by if it does happen (on the rare occasion), which is why they intrigue me. I've never actually put one on a blaster so I can't even tell you if it's a viable option or not. If they were solid plastic balls, I could do what you are describing, but they have a threaded hole on the inside so that doesn't quite work. If I had a round plunger rod, I could simply thread the end of the plunger rod and screw it into the ball. Unfortunately using a round plunger rod means all kinds of other bullshit you have to deal with, mainly the catch notch being able to rotate freely (not good).

I also just find the T-style priming handle to just suck in terms of comfort.

I understand your displeasure with hot glue, and those points are definitely valid. I have no patience waiting for glue to dry, which is a large part in my rationalization.

[F1Nerf]

How would one add this to the homemades directory?

[Naturalman7]

If someone is dumb enough to be seriously injured by the handle because they have no clue what they're doing, then they would likely also fall under the category of 'idiots who shouldn't play nerf'. Although I'd understand the concern if the target audience is much, much younger, but then you'd run into the problems of usability and danger of projectiles.

If they were solid plastic balls, I could do what you are describing, but they have a threaded hole on the inside so that doesn't quite work.

I think you, or I, or both of us are confused. I assumed you were going to use something like this 60975K51. If that's the case, then what I was trying to say is do this:
RBpistol Ball Knob by Naturalman_7, on Flickr

How would one add this to the homemades directory?

I don't know. Ask the directory's OP.

[Ryan201821]

Yeah that's pretty much what I figured I would do for the ball knob. I'm just concerned how well that will hold together.

I'm not saying it would "seriously" injure anyone, but maybe scratch someone or in the worst case draw a little blood. Obviously I'm being picky but I have to.

[Aeromech]

My pull-back priming disk.


Reverse-porn shot. I make my Rainbow pistols with omnidirectional catches and a round plunger rod, so this type of pull-back-disk is ideal. There is no wrong way to orient this disc, because, obviously, it's circular.

I like this because it doesn't require one to buy another part to make the pull-back mechanism, just make one more hole-saw cut into the polycarbonate plate you were already using to make the rainbow catch. Plus, I think it looks classy as hell. Not that I am not incredibly aroused by that ball knob...

I'm just concerned how well that will hold together.

This also has the added benefit of a flat plane contacting a flat plane; the flat pull-back-dick is held fast against the flat surface of the end of the plunger rod. This is opposed to a rounded surface against the flat surface of the end of the plunger rod, leading to the priming ball potentially being sheared off. Nearly this exact situation has actually happened to me. No matter what you do, there will be some kind of a moment on that part.

Edited by Aeromech, 16 July 2014 - 06:59 PM.

[Langley]

Dude, you are just a writeup machine. You've got what, a third of the contest submissions?

I've always used screws and electrical tape in my snaps. With liberal application of silicone grease in the plunger tube, it has always seemed to work as well as can be expected in a snap. I usually don't put too much tension on the tape so it compresses as it gets forced into the plunger tube. Definitely have a bit of a wiggle problem though, as mentioned above.

[Naturalman7]

I'd agree. I, too, am suspicious and generally uncomfortable with pulling on threads a lot. However, I had my +bow for several years being held together with such methods and it held up just fine. I think it may be worth trying and may be a viable solution. Just make the threads nice and not sloppy and deeper than .5" and the threads should stay intact. The only issue I see and have happened is the threads loosening due to being unscrewed. Solved by only tapping just enough depth for the screw so that the end of the screw 'bits' into the material. Loctite would help, too.

Also, the balls are flat on the side the threads are so it wouldn't be sphere on plane.

Oh, and I think pulling back on a disk sounds uncomfortable on the fingers.

Edit: Thanks Langley. I was serious in my last write ups and submissions when I said I saw your wish list. I just wish I had the personal time to spend on building. I've got RBpump, pumpbow, neanderthal SNAPbow, pumpSNAP with basic parts, as well as Pump Action Crossbow write ups all that I'm actively working on right now as well as updates to all my past write ups...but I don't think McMaster can send me the parts I need by the 21st.

And I can concur with Langley. My best SNAPbow has an absolutely perfect seal and hardly any friction and has screws, e-tape, and goop on the front bushing. The benefit of e-tape over packing tape is what I went over in my Pump-action SNAP 3.0 Write-up. E-tape has the properties of being stretchy so it can seal in such a way that packing tape cannot. It sort of compresses into the plunger tube and seals. However, it can wiggle because it's relatively skinny. I've found that packing tape may not seal as well, but it is excellent at keeping the bushing straight w/o wiggle.

Edited by Naturalman7, 16 July 2014 - 07:35 PM.

[archangel24]

3 screws going into the pushing and plunger tube could be used with added benefit - given that it is done correctly. When putting just two screws, or one long bolt through, the bushing has the ability to pivot on those screws/bolt. But if you add a third, it gives some added stability as the bushing is unable to pivot as if a rod were going straight through. So you could probably effectively get a great seal with using e-tape (use white or orange if you are nit-picky about looks and colour matchy matchy) and 3 screws while having great stability.

The ball knob concept is intriguing. Thread locker would help to keep from unscrewing but my concern is being able to get a good grip on it. Then in the realm of stripping threads, I feel the ball would be of more concern than the plunger rod itself.