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LOL, I'm popular like that. And kind of a hack with photoshop...

Guess what came in the mail today? Priority mail trucks in the Netherlands have A LOT of wheels! 6 days for shipping to the U.S. LOTS of comparison photos and measurements added to the first post in this thread. There IS a difference!

Keep your hand wrapped around the grip and if anyone tries to inspect or point out inaccuracies, unleash a FURY of airsoft pellets on them... How does it look now?

I'm pretty sure they know the grip is wrong...watch the video - they had to pack the entire gear drive inside the grip. The battery packs are specially made and tuck in beside the barrel. The grip may be wrong so they could fit the mechanism, but hey, it fires full auto! Not a bad trade-off.

The pipe on the right is 1.25" PVC electrical conduit commonly used with Doopy pipe builds. Specifications for each (left to right) Steel A513 Mild (onlinemetals): $9.49 USD for 24" (610mm) OD - 1.5" (38.1mm) ID - 1.37" (34.8mm) Wall - 0.065" (1.65mm) Weight - 0.9 lbs/ft Clear polycarbonate (McMaster-Carr): $8.58 USD for 24" (610mm) OD - 1.5" (38.1mm) ID - 1.375" (34.9mm) Wall - 0.063" (1.6mm) Weight - 0.15 lbs/ft Carbon Fiber (carbonfibertubeshop): $96.19 USD for 30" (762mm) OD - 1.495" (38mm) ID - 1.375" (34.9mm) Wall - 0.060" (1.5mm) Weight - 0.181 lbs/ft PVC (local home center): $4.25 USD for 10 feet (3048mm) OD - 1.660" (42mm) ID - 1.360" (34.5mm) Wall - 0.150" (3.8mm) Weight - 0.450 lbs/ft

Thanks Haui! I've been collecting building materials and had a choice for this one. The carbon fiber had the most appeal.

I think Vern is saying "old school" guys call it rubbing compound...'cause that's really what it IS, just much finer polishing media.

I'll NEVER know as much as Vern about these guns, so don't let him kid you. "Saves me tons of time..." - Vern you're a regular comedian here lately! You provided a deep, hearty laugh on this end, and for that, I thank you, sir!!!

OK, the whole tube is sanded... That was more work than I imagined. I've built two boats and I picked up a sanding trick somewhere along the way - thought I'd share it here. I kind of got in the habit of doing it anytime I'm sanding. Simple tip, but somebody may have never seen it. Basically, you make little sanding pads, but you make them so the sanding grits don't rub against each other (if the grits rub together, they wear down). When the side you're working with wears out, you still have three fresh sides...just unfold and re-fold to expose a fresh surface. To make them, start with your sandpaper, fold in half twice, unfold and rip or cut only ONE of the four fold lines. Then re-fold so none of the grit faces touch. Here's a picture progression of making a "long lasting" sanding pad: And here's the tube completely sanded! Wanna see something cool? I guess this shouldn't have been a big surprise given that this tube is the same size as my steel tube, but it was still a cool moment for me... Real Sterling parts fit in the carbon fiber tube PERFECTLY. Fitting real parts allowed me to verify my machine work was correct. Check the fit on the charging handle (I was stoked)!!! Most Doopy parts are ready to go. Waiting on DVH parts, hardware and t-track. Maybe I'll start grinding out the magazine housing for Steve's resin magazine next... Building tunes: "Jurassic Shift" literally 'shifts' like 4 times - it's like 4 different songs tied together! Great instrumental music for mundane work (like sanding): http://youtu.be/lzNPlQjL13A

Even sanding with 240, I don't see a single swirl mark anywhere. Maybe it's because the resin is SUPER hard because carbon fiber is made under extreme pressure? Either way, I like to have options and new tools, so I'll check out Amazon for micro mesh. Thanks for the suggestion!!!

Those fasteners are really just pins with both ends expanded to hold them in place. You could probably just get away with using a dremel and a small round bit to clean up the holes and maybe sharpen the end of a tube (homemade tool?) to define the outside edge. Fasteners look exactly the same from both sides. Here's some pictures:

After removing ONLY the trigger group retaining pin, you can remove the trigger group WITHOUT removing the grip. I didn't realize it until I tried it...I was always taking the grip off first, but found out I didn't have to... Are you sleeping, Brian? Dying to see more updates!!!

Thanks. LOL, I like this game because I know the answers... Always glad to help.

Now THAT'S an awesome picture!!!

Walt 80%?

Hi Francesco, It's only 8:00AM and I've already learned something today! The flat area on the bottom of the bolt is definitely angled. The milled flat edge is 12mm wide at the front and extends back to a 1mm diameter soft point, 13mm from the rear edge. I really had to mess with the lighting to get a good shot of this...the narrow end is difficult to see clearly!

400 grit lasts for about 30 seconds and then it's closer to 800 grit. The pile of dust on the bench is probably more silicon carbide than carbon fiber... Carbon fiber dulls saw blades and drill bits, so why should sandpaper be any different? In fact, the paper dulls SO fast, I switched to light strokes with 240 grit. After a few passes, I start to apply pressure and end up with the same result as a pile of 400 grit paper. If there's anything to be said for this project, it's that I'm going to end up with a bunch of new tools and consumables... that's my excuse, and I'm sticking to it! I have to say though, I'm quite pleased with the results!

Well, I think my test proved about as good a result as I could have hoped for... Direct from the Carbon Fiber Tube Shop FAQ: "What are the funny little lines on the tubes? Those are cello lines that leave a very small imprint in the top layer of resin. These lines are there because of the manufacturing process the tubes go through. Lines are evidence of the extreme pressures the tubes are cured under. Lines are good! The lines can be sanded smooth by removing a few thousandths of an inch from the outer diameter." LOL, I started my testing right by using "Empire approved" sandpaper... I separated test areas with thin strips of blue masking tape. Unsanded surface. See the "cello" lines running vertically? 400 grit sanding removed the cello lines, but left a dull surface. 600 grit sanding was a minor improvement, but still left a "satin" surface. Just for kicks, I whipped out the Novus #3 and #2 polish. That was the ticket. Smooth and clear. Pretty much EXACTLY what I had in mind!!! I see a bunch of sanding in my near future...

Thanks sskunky. Seems obvious to me in hindsight...

Thanks for likely sparing me some grief, Ian... I didn't even think to try an offcut, even though I cut a 1/2" wide ring as a "test" cut...I was just going to dive right in with the 400 grit. Sanding tests commencing now...

Not yet. Ridges are still there. They're REALLY small, but they diminish the sleek, high-tech look I've got in my mind for the finished product. I'll probably sand the whole tube with 400 grit, then 600 grit once I work up the courage to knock down the gloss on the tube... and waiting to see how my Roy tracks look over the holes. Can you see them now?

Small update: I finished all the straight cuts in the carbon fiber using a diamond cutoff wheel. Since I repositioned the tube many times to get the most comfortable cutting angles, I did not use a shop vac. For these cuts, I wore a half face respirator and safety glasses. I left portions of the template attached for now (just in case I get busy and can't work on this for weeks). There are also very faint cut lines on the tube from the razor blade, so that should help when positioning and pinning resin parts. Then lots of "fiddly" prep work with resin parts...

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!

JBWeld is epoxy...

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...