USR Weightlofter

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

lalligood

Well-Known Member
Joined
Jan 21, 2009
Messages
1,985
Reaction score
0
A full review for EMRR is in the works but I thought I'd give an early preview here (especially since it'll be 2 or 3 more weeks before I get to fly it!)

I started working on the second of 3 USR kits that I received in the past week or so. The Weightlofter is a fairly challenging to build mid power 7-motor cluster rocket that is similar to the USR AeroRoc. It has a central 29mm MMT surrounded by 6 24mm motor tubes that actually are about halfway exposed outside the the 2.25" main airframe tubing. It can fly on one central motor (required for chute ejection), or with 2, 3, 4, or 6 outboards. There is a 24mm motor adapter included if you want to use all 24mm motors too. The root edge of the fins mount into the wedge of a pair of motor tubes (like the Loc Viper & TriStar) as well as flat against the main airframe near the leading edge. This robust motor configuration and fin attachment gives the Weightlofter an aggressive look. Nose weight is required for most clustered flights.

I used yellow wood glue (aliphatic resin) exclusively for the build. Yellow wood glue is still stronger than the wood and/or cardboard materials themselves but doesn't have the weight penalty of epoxy.

The build starts with building the motor mount. There are 2 centering rings that are glued near one end of the 29mm tube. The main airframe tube is marked for fin alignment and then the MMT tube is glued with about half of the 29mm tube exposed out the eft end. Then the 24mm motor tubes are grouped and glued into pairs. Once dry, all 3 pairs of tubes are glued onto the 29mm tube with the crease of the tubes lined up with the marks on the large airframe tube. Let everything dry.

The fins are laser cut 1/8" birch ply. They are mounted into the valley of the 24mm tubes and the root edge is so long that it lays along the 2.25" airfram too. In order to get them flush with both surfaces, I used my Dremel with a sanding drum to shape the aft 3" of the root edge into a V shape. Fins were then attached one at a time and allowed to dry before attaching the next one. Fillets were done equally as patiently.

Because the motor tubes extend so far outside the main airframe, I decided to use the included launch lugs instead of my personal preference of rail buttons. I guess I could've used rail buttons but I would have had to build some pretty high standoffs.

The rest of the rocket was fairly routine: put screw eye in bulkhead, glue bulkhead in coupler, glue coupler in payload tube. Hard balsa nose cone (typical in USR kits) is left to friction fit so that nose weight can be added when needed.

Recovery is a long piece of 1/4" elastic attached to the screw eye in the payload and the tried-and-true 3-fold attachment inside the body tube. Surprisingly (at least based off of other USR reviews on EMRR), the chute was a 16" mylar--instead of a supposed paper--chute with Kevlar lines and a snap swivel! This might be a little on the small side for clustered flights and/or if landing on hard surfaces is likely, but I've got a spare 18" nylon chute in my range box if I ever want to swap it out for something a little bigger... Instructions are also included with the chute on making/using a metal or tape ring to aid in a more gentle chute deployment. I was able to make one out of 2 pieces of masking tape with the adhesive turned against each other.

Construction complete. Now on to the finishing.

The balsa nose cone was coated with finishing epoxy & the fins and nose cone were smeared with diluted Elmer's Fill 'n' Finish and then sanded with 320 grit. Primer & paint are in the near future... Paint scheme is probably going to be orange and red to match (at least colorwise) with my beloved Banshee.

That's about it for now. Pics to follow...
 
Last one for now. Here it is with the build complete & ready for finishing. Hoping to at least start the paint work this weekend...
 
I reallly like this review. Why not sand an airfoil onto the fins? I guess this is common for folks to leave out "Step #1". It is "Step #1" for a rerason! 15% drag reduction.

Jerry
 
Originally posted by Jerry Irvine
I reallly like this review. Why not sand an airfoil onto the fins? I guess this is common for folks to leave out "Step #1". It is "Step #1" for a rerason! 15% drag reduction.

Jerry

OK, you caught me... I'M BEING LAZY :rolleyes: hehe Seriously though, the fins already look so good being laser cut and the Weightlofter isn't going to set any speed records (unlike the plans I have for my Miniroc 1.2 :cool: ) yet is still going to get plenty of altitude when it's got 7 BP motors in it ;)

Thank you for the compliment too :D
 
WOW!

That rocket looks ready to kick some major booty!

Jerry, contact me and let me know how I can buy one of the things! It would be a great addition to my fleet! :D:D

Jason
 
Originally posted by jetra2
Jerry, contact me and let me know how I can buy one of the things! It would be a great addition to my fleet! :D:D

I'll save Jerry the hassle & save you time, Jason.

Go to the USR ordering page and follow the directions. Be sure to look at the Instaship page to make sure that he has it in stock (which the Weightlofter is).

Like Jerry says, order now; pay later. I know what you're thinking..."That's it? Is that really how it works? What's the catch?" The answers are Yes, Yes, and no catch, respectively. It just works. USR (& their kits) rock :D :cool:

FWIW, eugenefl saw me fly my USR Banshee (currently NOT in stock) back in October at NEFAR. He got a good look at it up close.
 
Originally posted by jetra2
WOW!

That rocket looks ready to kick some major booty!

Jerry, contact me and let me know how I can buy one of the things! It would be a great addition to my fleet! :D:D

Jason

simple.

Send an email to [email protected]

somewhere say Weightlofter!

Somewhere put an address.

Boom. It be shipped.

Jerry
 
E-mail sent, Jerry!

You know, if you should get into trouble for any one thing, it would be appealing to the cluster lover in me! :p

Can anyone say 6x C11-0 and 1x E9-6~? Drool! Would be a great park flyer with all the smoke n' fire pouring outta it! :D:D

Now the ball is in your court, Jerry. Let's see if USR stands up to the ol' "Jason Test"!! :)

Jason
 
Originally posted by jetra2
E-mail sent, Jerry!

You know, if you should get into trouble for any one thing, it would be appealing to the cluster lover in me! :p

Can anyone say 6x C11-0 and 1x E9-6~? Drool! Would be a great park flyer with all the smoke n' fire pouring outta it! :D:D

Now the ball is in your court, Jerry. Let's see if USR stands up to the ol' "Jason Test"!! :)

Jason

Order already packed.

oh, and, oops!
https://www.v-serv.com/usr/custom.htm
 
Jerry does not mess around with Instaship. My orders have been sent very quickly. Now if I could just build the rockets as quick...
 
Originally posted by Jerry Irvine
Order already packed.

I get the impression that Jason didn't look over the InstaShip page more closely & notice that the *12* motor cluster Swarm Jr (24mm) is available :eek: :eek: Better buy stock in Estes before ordering one of those :D :cool:
 
Originally posted by jetra2
Can anyone say 6x C11-0 and 1x E9-6~? Drool! Would be a great park flyer with all the smoke n' fire pouring outta it! :D:D

Jason
How about 6xE9-P and 1xG64-10W? THAT would REALLY give it a kick off the pad. You would just have to hope the G64 ignites well - if all the E9's lit, but the G64 didn't that would have a nice arcing flight up and back down again. It would give you a nice core sample, too, complete with all the layers.
 
Originally posted by cjl
How about 6xE9-P and 1xG64-10W? THAT would REALLY give it a kick off the pad. You would just have to hope the G64 ignites well - if all the E9's lit, but the G64 didn't that would have a nice arcing flight up and back down again. It would give you a nice core sample, too, complete with all the layers.

That would be a sweet combination indeed but it's quite unlikely that I'll mix BP & AP motors in the same flight. I'll either do a cluster of BP motors (like 3 x D12-0s + E9-8 in the center) or stick to a single AP motor (in the AT 29/40-120 range).

UPDATE: The weather & wife have been cooperative plus having some free time lately. I'm hoping to have it finished in time to launch this coming weekend! I wasn't planning on launching the Weightlofter (things had been rough the past couple of weeks) but this will probably be my last big launch of 2004 & I'd rather not wait till January to launch it...
 
I received my Weightlofter last Friday while I was at ROCStock. According to my mom, the package wasn't taped up very well and dinged on the ends. Luckily, the rocket wasn't damaged, but I would've been more impressed if there was packing material (newpaper or kraft paper) and better taped up.

Heckuva packaging job for the kit itself, though, Jerry. Impressively packed to make it look like there's tons of parts in there (which there are!). Might start construction tonight or tomorrow, with pix, so keep a heads up!

Jason
 
Well, I didn't get to finish all of the painting but I did get the Weightlofter fully primed. So I can get out there & launch it at least once tomorrow, right? I'll start with just a single motor--a F52-8T--and we'll see where we go from there. I'll finish painting it later this weekend or sometime next week for sure :)

BTW, how's yours coming along Jason?
 
Mine's coming along nicely. I got the fins rounded, 24mm mounts built, 29mm mount built and installed, and coupler made. I made a small mistake in applying fillets to the 24mm mount and so the fins, when on, won't touch the main body tube. Not a big problem...just have to figure out the solution.

Jason
 
Originally posted by jetra2
Mine's coming along nicely. I got the fins rounded, 24mm mounts built, 29mm mount built and installed, and coupler made. I made a small mistake in applying fillets to the 24mm mount and so the fins, when on, won't touch the main body tube. Not a big problem...just have to figure out the solution.

Jason

Check out the fifth paragraph of my first post in this thread. I think you'll find the answer there... Keep us posted ;)
 
Originally posted by jetra2
WOW!

That rocket looks ready to kick some major booty!

Jerry, contact me and let me know how I can buy one of the things! It would be a great addition to my fleet! :D:D

Jason

Me too! I would love one of those things! I've built serveral clusters with only 2 working like they should. So one of these babies should put a change to that :D
Karl
 
Originally posted by Karl
Me too! I would love one of those things! I've built serveral clusters with only 2 working like they should. So one of these babies should put a change to that :D
Karl

simple.
Send an email to [email protected]
somewhere say Weightlofter!
Somewhere put an address.
Boom. It be shipped.

Jerry
 
I have some good news for folks out there interested in the USR Weightlofter. I successfully launched it today on a F52-8T. It left the pad like a scalded dog :D I'd guesstimate that I got a good 1500' out of it. The mylar chute with the tape ring (to ease deployment) worked *beautifully*. I like my Banshee but I think I could like this one more ;) Super rocket-motor combo...if you want to fly it on only 1 motor.

But you're saying, "It's a cluster rocket. Why'd you only launch it on only one motor?" Patience, my friend, patience. A guy showed up at the launch today to basically sell off his entire collection of rocketry related kits, motors, & supplies. Silly me only had $20 on me but I did walk away with two 3-packs of D11-P motors & one 3-pack of E9-8s. All for $10 :D How does 6 D11-Ps & 1 E9-8 sound? The downside is that I didn't have any nose weight--nor did I know how much it would take to make it stable without being overkill... So, for anyone coming out to NEFAR in December (*cough* Eugene *cough*), guess what I'll be launching?!? hehe :cool: I can't wait!
 
Originally posted by Jerry Irvine
simple.
Send an email to [email protected]
somewhere say Weightlofter!
Somewhere put an address.
Boom. It be shipped.

Jerry

Thanks Jerry! :D :D Ill do you a complete write up on EMRR & the UKRA 10..9..8.. mag :p

Thanks
Karl
 
I finished painting my Weightlofter today. Need to leave it alone for a little while but I'll post pic(s) later today or tomorrow.

jetra2,
What's the latest on yours???
 
Pics!!!

First up is the flight picture from last weekend. I only had the Weightlofter covered in primer at the time. Flight was on a F52-8T. Perfect ascent & recovery!
 
And then I finished all of the paint work yesterday. Here she is in all her shiny goodness :D
 
Originally posted by jetra2
Mine's coming along nicely. I got the fins rounded, 24mm mounts built, 29mm mount built and installed, and coupler made. I made a small mistake in applying fillets to the 24mm mount and so the fins, when on, won't touch the main body tube. Not a big problem...just have to figure out the solution.

Jason

i had the same problem with mine so i air foiled the 2/3 of the bottom part of the fins that would touch the mms and that worked quite nicely
 
Originally posted by bachsta
i had the same problem with mine so i air foiled the 2/3 of the bottom part of the fins that would touch the mms and that worked quite nicely

If there are any warnings that can be put into the instructions, let me know. Also photos!

Kids are our future. That is an understatement.

Jerry
 
Originally posted by Jerry Irvine
If there are any warnings that can be put into the instructions, let me know. Also photos!

Check out my 5th paragraph in the very first post of this thread. I noted that this needed to be done way back then. I don't have any pics other than the one of the aft end fully assembled (which should also be in this thread & I emailed to you).

This kit was clearly designated skill level 3. That is very accurate of its difficulty & effort required in building the Weightlofter. That was part of my attraction to buying this kit & I was not disappointed in the least! :D
 
I've just got my USR Weightlofter kit, thanks USR ! I opened the packaging and was stunned by the quality of these parts, and a nice thick instruction guide :D I carn't wait to start building her... But I will leave it till after Christmas, in-case I get a new digi cam :p

I found the ACE Information Report on how to Cluster, Motor Install & Stage btw Jerry, thanks! Alot of tips that I've never thought of in there.

Thanks once again,
Karl
 
Back
Top