DVH Pipe Build with Extras

[T-Jay[TK]]

Hey Ian, somehow missed your thread until now. Good work so far, really like it.

 

Waiting for your next update...  (following)

[usaeatt2]

Good to have friends with torches! That's cool you can separate those parts like that.

 

Nice work.

You can use the exact same method to separate the rest of the parts from a Sterling parts set.  Magazine well is the most difficult to do without hurting the part.

Not sure why there's no locating pin...maybe an older version?

[gazmosis[501st]]

What are you going to mate the hinge point to the pipe with? There's a lot of stress there! I have my doubts that glue will work here.

[I'm Batman[501st]]

Thanks Tino and Aaron.

 

What are you going to mate the hinge point to the pipe with? There's a lot of stress there! I have my doubts that glue will work here.

 

That was my exact concern too. However it is exactly the same size and fitment method if I used the DVH hinge bracket and others that I've spoken to suggest that an epoxy type glue will mate the the metal to PVC as effectively as resin to PVC. I will be using locating pins aswell. If it fails, then I guess I can try the DVH resin bracket. Any other thoughts seeing as it isn't preformed like a Doopy kit?  

[usaeatt2]

I'd pin it and epoxy it.  Don't forget to loosen up the holes in the stock arms - gazmosis did a really nice demonstrating this procedure in his folding stock build.  I used his process and my folding stock doesn't bind anywhere.  If the epoxy fails, pull out the pins, drill and tap "blind" holes for 4-40 screws in the stock pivot, then screw it to the receiver from the inside...won't be easy, but the holes are close enough to the back of the tube that you should be able to insert them with long needle nose and tighten them down with an allen wrench or 90 degree offset screwdriver through the charging handle slot.

[I'm Batman[501st]]

Good idea Aaron. I'll have a closer look at that tonight. Worse case I could drill a small hole in the receiver wall to gain access with the screwdriver, then fill it prior to painting. I've already done this to accommodate a charging handle mod I've got under way. I would just have to make sure the screw heads don't foul the movement of the inner bolt. Already given both parts of the arm/bracket a going over to minimise binding. Operates nicely  .

[usaeatt2]

If you're filling holes prior to painting, it might be easier to just screw the stock pivot on from the bottom and fill the holes.  Probably less obvious on the bottom than on the receiver...

[TK bondservnt[501st]]

JBweld is stronger than epoxy

[usaeatt2]

JBweld is stronger than epoxy

 

JBWeld is epoxy...

[I'm Batman[501st]]

This is the stuff I have at the moment - JB Weld Steel Reinforced Epoxy. World's strongest, even! 3960psi

 

http://www.jbweld.com/product/j-b-weld/

 

[usaeatt2]

This is the stuff I have at the moment - JB Weld Steel Reinforced Epoxy. World's strongest, even! 3960psi

 

That should work just fine.  I've used JB many times for conventional AND unconventional repairs.

I also REALLY like West System Epoxy because I can "customize" it to my needs.

Special pumps dispense resin and hardener in exact proportions.  Different modifiers add different properties to the hardened epoxy.

I use a lot of colloidial silica, which increases the adhesive strength.  I've also used aluminum powder (mostly for color) and low density fairing filler (for easier sanding).

 

Wear gloves and good luck!

[Dday[501st]]

JBWeld is epoxy...

BAM!

 

 

 

This is the stuff I have at the moment - JB Weld Steel Reinforced Epoxy. World's strongest, even! 3960psi

 

http://www.jbweld.com/product/j-b-weld/

 

Ian, have you thought about doing this on a aluminium tube, or a steel tube? It just seems a shame to do all this work for a lowly PVC tube. I never really even thought about this prior to just now.

 

It is like putting 100k work of parts into a 10k car.

[I'm Batman[501st]]

Ian, have you thought about doing this on a aluminium tube, or a steel tube? It just seems a shame to do all this work for a lowly PVC tube. I never really even thought about this prior to just now.

 

It is like putting 100k work of parts into a 10k car.

I did. That was my first thought, and I have the Ikea table leg in the garage. However it's only 1.1mm thick compared to 2.6mm so your inner bolt is a bit loose and the front and rear ends are also loose. Seems like they were made for PVC. But mainly it wouldn't be thick enough to allow the use of securing pins. I am skeptical, as Steve was, to the strength of expoxy on it's own. It won't be my main trooping weapon, but it will certainly get a lot of use 'showing off' to my mates... Edited November 14, 2014 by Sith Lord

[I'm Batman[501st]]

Jeez, Derrek.... Your making me think here. Yes, local Aussie ebay has 40mm OD x 34mm ID aluminium tube for not a lot of $$. You main 3 items - inner bolt, front muzzle and rear cap lock all have about a 33-34mm diameter, so would be perfect. Might have to put this build on hold for a bit.

Edited November 14, 2014 by Sith Lord

[Bulldog44[TK]]

If the aluminum tube doesn't break the bank, give it a try, you can always order a Doopy pipe build kit to use your PVC tube. Then you'll have 2 blasters!

[I'm Batman[501st]]

Aluminium in hand. Only $9- so why not... Tell you what, its a bit harder than PVC is. I need some more dremel bits for grinding/smoothing out some of the curves (ejection port, misaligned holes, etc). I assume the Aluminium Oxide bits for the dremel are the best??http://www.dremel.com/en-au/Accessories/Pages/ProductDetail.aspx?pid=932 Any other suggestions? Pics to come soon.

 

[usaeatt2]

Step bit and a drill press.  I think aluminum oxide bits would tend to "load up" with aluminum.

Derrek is the expert on aluminum tubes - I'd go with whatever he says...

[I'm Batman[501st]]

Yeah, maybe that's why I struggled a bit. Typical me though, didn't want to fork out the $$ for an expensive step drill bit so have done the 2mm, 4mm, 6mm, 8mm increments on the drill press. Some of the holes just need a bit of tidying up... 

[TK bondservnt[501st]]

JB WELD IS METAL INFUSED RESIN  POLYMER also known as epoxy

 

there are reasons why it's better than standard plastic epoxy

"

J-B Weld is The Original Cold Weld two-part epoxy system that provides strong, lasting repairs to metal and multiple surfaces. Mixed at a ratio of 1:1, it forms a permanent bond and can be shaped, tapped, filed, sanded and drilled after curing. At room temperature, J-B Weld sets in 20-25 minutes to a dark grey color. A full cure is reached in 15-24 hours. J-B Weld has a tensile strength of 3960 PSI and sets to a hard bond overnight. It can withstand temperatures up to 550ºF when fully cured.

"

 

do those specs sound like the average epoxy?

 

no

Edited November 19, 2014 by TK Bondservnt 2392

[usaeatt2]

Sorry Ian, but I can't avoid a response...

 

JB is AVERAGE epoxy with good consumer marketing (as quoted above).

It works well for the purposes of prop making and tolerates mixing ratio errors.

 

You could probably fill this forum with the research done on higher grade epoxies.

There are many manufacturers, but I prefer West System due to their extensive research, publications and technical assistance.

Another good epoxy is System Three.

Users can customize these epoxies to meet specific structural needs and even make a "metal infused resin polymer".

My first gallon of West System came with a BOOK to introduce the properties and chemistry involved and it's NOT cheap.

The plain, unmodified version of their epoxy cures to over 7,000 psi tensile strength and can go much higher with additives. 

 

Here's a WAY OVER-SIMPLIFIED chart showing options for an "above average" epoxy:

 

Every choice changes the physical properties and sometimes results in the need for technical assistance.

Mixing ratios have to be EXACT, hence the need for ratio pumps.

I've built two boats for Lake Michigan and I've used AT LEAST 30 gallons of modified epoxy.

Every product has it's place.  I wouldn't trust my life to JB Weld, but I've done it several times during storms on the lake with West System.

 

 

JB Weld is an AVERAGE epoxy, but for cost, ease of use, purchase just about anywhere and catchy advertising, it's GREAT.

 

Back to your regularly scheduled blaster build, and again, sorry for my off-topic rant.

Edited November 19, 2014 by usaeatt2

[Dday[501st]]

I have yet to find a nice sanding style blade for Aluminium, everything I use gets loaded up with Aluminium and becomes basically useless.

 

Your standard dremel grinding disks are good for grinding and cutting but for sanding and cleaning, what I have used is a big wood and metal file. You know the one it's it like a foot long and has two different sides. This works out the big stuff and the fine side gets a nice fine grind to it. For the more detailed work I have one of those small metal file sets with 6 different files in it.

 

The sanding drum can work as well on Aluminium but will wear out quickly.

 

If you really want a multitool bit for shaping aluminium, first, don't get Dremel brand, they cost more. Generics work great, and get the metal bits like these. http://www.el34world.com/Misc/bike/images/dremel.jpg

[I'm Batman[501st]]

I wouldn't trust my life to JB Weld, but I've done it several times with West System.

 

Back to your regularly scheduled blaster build, and again, sorry for my off-topic rant.

 

 

Haha, no problems at all Aaron. We can once again rely on your highly detailed response with informative useful information. Thank you. I probably bought the JB Weld because it was a GOOD product (with a good marketing hype). As we're not building a life dependent blaster I'll stick with the JB for now, and if it fails take some of that great info and look for something better. Cheers.

 

 

I have yet to find a nice sanding style blade for Aluminium, everything I use gets loaded up with Aluminium and becomes basically useless.

 

Your standard dremel grinding disks are good for grinding and cutting but for sanding and cleaning, what I have used is a big wood and metal file. You know the one it's it like a foot long and has two different sides. This works out the big stuff and the fine side gets a nice fine grind to it. For the more detailed work I have one of those small metal file sets with 6 different files in it.

 

The sanding drum can work as well on Aluminium but will wear out quickly.

 

If you really want a multitool bit for shaping aluminium, first, don't get Dremel brand, they cost more. Generics work great, and get the metal bits like these. http://www.el34world.com/Misc/bike/images/dremel.jpg

Good tips. Thanks Derrek. As Aaron previously mentioned and i have found about the bits clogging up.... I am almost where I need to be, just with my hand file. But I will look at some of the metal grinding bits. Heading to the shop tomorrow, so I'll check them out. Thanks.

[Dday[501st]]

You can also use a hard bristled wire brush to clean the bits out... but it takes time.

[usaeatt2]

You can also use a hard bristled wire brush to clean the bits out... but it takes time.

 

I knew Derrek would have experienced this!

I use an ice pick to get the aluminum chunks out of the teeth on my files, then a wire brush.

I also have an old Colton file cleaning brush with a small pick, but sometimes it's not enough to get the chunks out.

 

Edited November 22, 2014 by usaeatt2

[Dday[501st]]

The biggest problem with he little little dremel bits and aluminium is that as fast as the bits turn, they do a fair bit of melting at the same time as grinding. The alu melts just enough to REALLY get into the cracks and be really hard to get out since it is in all the little crevices in the bit.