MAC Performance 3in. HV ARCAS - Canvas Composite Tubing, Precision Manufacturing...

[patelldp]

How much does it cost to weigh it? Before I had a Scale of my own I used to take my Rockets to the Deli.

I will weigh it tonight. I have a 3" FG tube that I will weigh to compare #/in.

 

[patelldp]

Truly awesome. Any idea what other kits will be available? A 54/38mm kit like this would be nice. What glue do you plan to use?

There are a few designs in the works. 54/38 may be in the works, I'll have to ask. I really only know about the ARCAS.

I will be using Bob Smith 30 minute for primary glue, Rocket Poxy for filleting.

I intend to clean off my bench tonight and I will pick this back up!

 

[patelldp]

Do you know prices, or if there is a website? When will they be available?

s6

Jerk

 

[JDcluster]

I'm thinking 2" sized liners for the 2.5" Kosdon hardware..... Just the liners.
If he can develop some kits using tubing that would also fit the 2.5" hardware it might boost enough interest to work out???


JD

I have asked and pleaded! Truth of the matter is that the market just isn't the same as kits. You know the points that Scott K. from Loki has made, and they are all deterrents from stocking motor liners.

 

[patelldp]

I'm thinking 2" sized liners for the 2.5" Kosdon hardware..... Just the liners.
If he can develop some kits using tubing that would also fit the 2.5" hardware it might boost enough interest to work out???


JD

First off there's very few people interested in those liners. Probably fewer than 10, certainly less than 25.

Secondly, developing a kit around that tube size would require a nosecone mold. That's a massive investment driven by a very small demand liner. Why not just design kits around standard diameters without that barrier to entry?

Lastly, it's easier for a tube to be made that is reliant upon an accurate ID than an OD. As mentioned before, Scott K will tell you about tolerances. This tubing is wrapped around a mandrel. His couplers, as stated before, are ordered with an oversized OD and then machined to a precision fit.

The reason these liners don't exist is because there is simply no market for them.

(These are my opinions, not MAC performance's)

 

[patelldp]

Here's your bit of fun for the evening:

[YOUTUBE]gKQvtlXvDmc[/YOUTUBE]

I felt the only way to truly show the quality was via a video showing the fit of these parts. Second to none.

Build thread to start this week!

 

[H_Rocket]

Have you tried any operations on the material? Wondering if it drills w/o flaking.

 

[patelldp]

Have you tried any operations on the material? Wondering if it drills w/o flaking.

There is zero chipping on the tube ends and the routed fin slots. Step one will be to drill and tap for the rail buttons and I will be sure to document!

 

[patelldp]

Have you tried any operations on the material? Wondering if it drills w/o flaking.

Ask and you shall receive...

Drilled and tapped for 8/32 rail buttons. What you see here has been cleaned up by simply removing any chips with my finger.

 

[H_Rocket]

Yowza!

 

[patelldp]

Yowza!

It acts a lot like that stuff people loved that is no longer available...was it G10 tubing?

 

[grouch]

I want this with a 38mm mount.

 

[rfjustin]

I want this with a 38mm mount.

Why not just adapt down from 54mm to 38mm?

 

[patelldp]

I ordered a 54mm Aeropack, two 12x12 chute protectors, and 16oz of 4# two part expanding foam for this build. Going to go old school and foam the fincan as it's a realtively small area that isn't conducive to filleting internally. It's not my favorite way to do it quite honestly isn't necessary, but I'm going to give it a go.

Epoxy will be mixed tonight for this build, specifically to install the shock cord mount and attach the two fore CR's!

 

[H_Rocket]

It acts a lot like that stuff people loved that is no longer available...was it G10 tubing?

Funny thing is I like working with phenolic. I can glass it if I want, don't have to and it is strong and light.

Let us know how well this new stuff takes epoxy.

 

[grouch]

Why not just adapt down from 54mm to 38mm?

No need to have more than needed and a 38 will outfly my available fields.

 

[Viperfixr]

I am really intrigued by this new kit and airframe material. Your video on YT was very interesting--love the attention to detail and fit of the new kit pieces.

How would you compare this airframe material to the other offerings available, such as thin-wall FG, Blue Tube and LOC tubing? Is it brittle like some phenolic airframes?

 

[patelldp]

I am really intrigued by this new kit and airframe material. Your video on YT was very interesting--love the attention to detail and fit of the new kit pieces.

How would you compare this airframe material to the other offerings available, such as thin-wall FG, Blue Tube and LOC tubing? Is it brittle like some phenolic airframes?

Great question, and that's really what this kit comes down to.

Thin Wall fiberglass is probably approaching the weight of this tubing on a g/in basis, but I don't have a piece to confirm. This tubing is 14g per inch, best I can tell. Thick wall FG is 22g per inch. The downfall to thin wall is that it requires all new parts and doesn't promote interchangeability with legacy parts.

It's worlds stronger than LOC tubing, doesn't have spirals, and doesn't delaminate. It's also water resistant.

Blue Tube is another animal. I've heard that it isn't great in terms of dimensional stability and it can warp unless you apply minwax to seal it. Whether or not that has been solved with BT2 is not known to me. Again, BT has spirals.

The tube isn't brittle. It doesn't chip when cut or drilled, and has a nice, subtle flex to it when you squeeze a tube opening really hard. The 3" tube flexes approximately as much as my 38 Special thinwall FWFG tube does.

 

[accpool]

This looks like a great material, waiting patiently on your build. So should I ask how much and when it will be available? Just kidding:blush:

 

[DizWolf]

No need to have more than needed and a 38 will outfly my available fields.

24K is only a hop, skip and a jump away

 

[DizWolf]

Blue Tube is another animal. I've heard that it isn't great in terms of dimensional stability and it can warp unless you apply minwax to seal it. Whether or not that has been solved with BT2 is not known to me. Again, BT has spirals.

I use a lot of Blue tube. I haven't had warping issues, but I keep mine relatively dry. It certainly swells and shrinks with heat/humidity. I haven't had anything bind yet...but My Optima's NC gets pretty tight.

Those spirals.....those deep....deep effeing spirals....

 

[REK]

Here is my curious question. How strong are those new composite tubes? In your opinion do you think it can handle up to Mach 2?

 

[cavecentral]

I have used some blue tube 2.0. Worked great. I had a core sample out at Thunderstruck last Spring. I left the mud in until I got home. That piece needed replaced. Was too deformed. Tubes are pretty long to fully seal inside and out. I sealed the couplers / ebay outside and the inside of the airframe that needs to have the coupler fit.

More options are usually good. Strength, weight, price, ease to work with, etc.

 

[patelldp]

Second step (after drilling rail button holes) is to figure out the spacing of the two fore-most rings. This is can be difficult when the rings that come with a kit or that you cut yourself don't fit well. The precision fit of these CR's allow me to accurately place and mark them for epoxy. Usually I would butt the mid CR against the fore end of the fin tab, but considering I will be using foam inside of the cavity I wanted space for the foam to flow and fully encapsulate the root. I've spaced the CR from the fin ~0.375".



Next step was to back the CR's toward the aft of the rocket to allow me to scuff and apply epoxy. I always push the CR's forward vs. aft because of the uniform fillet that results. This fillet is on the fore side of the CR which absorbs the most thrust under boost and transfers that force into the body tube. The aft side will receive a fillet later.



Here's the picture of the resulting fillet. One thing to be sure of is that you don't get epoxy into the hole for the shock cord. Epoxy will be added here later, but for now we want it free and clear of any epoxy to allow the shock cord to pass through cleanly in the next step. Note that this tubing is seemingly identical in behavior to other kraft phenolic tubes available on the rocketry market. It sands nicely and accepts epoxy very well.



The epoxy is curing now and I intend to install the shock cord assembly tonight before bed so I can leave it on my boiler overnight for a poor man's "curing oven" effect!

(Oh wait, is that the ARTS2 I have for sale in the Yard Sale in the background? THREADCEPTION! If no one buys it I may put it in this rocket...if someone does I will put the proceeds toward my new lathe fund!)

 

[TopRamen]

Bummer.
I was hoping to hear about how much it weighed before you started building it.

 

[patelldp]

Bummer.
I was hoping to hear about how much it weighed before you started building it.

The contents of the bag (including the small amount of epoxy I added to the MMT) is 1,655g or 3lbs 10.3oz. Assuming you're not certified and would like to fly this without the extra altimeter bay hardware, you could easily get this below 4 lbs on the pad.

The G10 fins are a heavy part, but necessary for the upper level motors this thing is capable of flying on.

 

[patelldp]

One of the coolest features of this kit is the engineered shock cord mount. A lot of kits suggest epoxying a 1" Kevlar strap to the motor mount and I have utilized that method on several rockets with great success. This method doesn't take up any real estate on the motor mount tube and won't make you think about alignment with fin slots. I've also been told it's strong...tests have shown that the tubes will fail before the mount based on an EXTREME test.

First, let's describe the parts. The kit comes with a bridle made out of 9/16" TN that has loops sewn on both ends. The other major part is the pin. The bridle is sized such that it sticks out above the booster tube after it is installed to make attachment to the full length shock cord very simple.



The pin gets slipped through the loop...



The cord gets passed through the centering ring and then the pin gets pressed into the milled recess...



Then you smother this cavity in epoxy and let it cure! Done!

 

[RKeller]

seems like a nice attachment method, a kevlar option would be nice for those using motor eject.

 

[patelldp]

seems like a nice attachment method, a kevlar option would be nice for those using motor eject.

Riley,

Not a bad suggestion and certainly a modification that you could make to your kit. MAC will be offering nomex sleeves for sale and one could be added to this rocket to cover the bridle.

I intend to keep it as is. I will be flying this almost exclusively with electronic deployment. The thought has crossed my mind to fly this rocket in "half mode" on a CTI 38mm 1G G50 Imax, and if I do I will use a sleeve.

 

[Bat-mite]

This looks amazing. Could revolutionize the industry.