NEW 8" GIZMO XL FROM PERFORMANCE ROCKETRY

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Hey Gary,, Where did you find the attachment eye you used on your piston?

Thanks,
Tom
 
Are you guys sanding the gel coat seam off before test fitting??? I have built a Ton of PR kits and have only ever had to give them a light sanding, Try using a pure silicone rather than all the sanding.
 
Hey Gary,, Where did you find the attachment eye you used on your piston?

Thanks,
Tom

Tom, Eye bolt is nothing special I got it at my local Hardware store, There is no real pressure on it and its only holding itself to the chute so a closed forged eye bolt is not needed.
 
Are you guys sanding the gel coat seam off before test fitting??? I have built a Ton of PR kits and have only ever had to give them a light sanding, Try using a pure silicone rather than all the sanding.

Yep I filed off the seam,,, then started sanding, In some spots I have sanded all the way through the gel coat.
 
Gary
There was no way the nose cone of mine would even start to slid in the tube. I have had to sand so much the darker color of expoy and fiberglass is starting to show. Maybe the tube size is off a little. Its no big deal to me I have done it before but one should not have to do it. This will be a great kit to fly.
GP
 
Something I noticed,,, when together,, the NC is larger diameter than the AF tube. I had to sand the outer side of the centering rings as well,, I suspect somehow the AF tubing is smaller,,, I don't know how that would be possible as it is made on a mandrel,, but I don't know

Tom
 
Glad I am not the only one having issues with the PR cones. I was determined to get mine to work (at least somewhat) on my regular Gizmo. I have pretty much sanded all of the gelcoat off (although mine is really out of round as well).
 
I would suggest putting the bulkplate in the base of the nosecone first before doing a lot of sanding. If you haven't already done that, it can really help correct a cone that is out of round and reduce the sanding needed. Not saying mount it permanently, just slip it in place.

Mark
 
Gary
There was no way the nose cone of mine would even start to slid in the tube. I have had to sand so much the darker color of expoy and fiberglass is starting to show. Maybe the tube size is off a little. Its no big deal to me I have done it before but one should not have to do it. This will be a great kit to fly.
GP

My Gizmo XL nosecone is also tight. I sanded off the seams, chamfered the end of the nosecone and the inside edge of the airframe tube. The cone goes in about 2 inches with some friction, then binds up. :(

The nosecone shoulder is not at all out of round by the way. (luckily) I can see that sanding the nosecone shoulder will definitely involve going through the gelcoat. This really isn't right. I think the airframe tubes are undersized and there might be very wide sample to sample variation. :rant:

I have a 3" diameter by 3" long drum sander I'm going to try using on the inside of the airframe before I attempt sanding the gelcoat off of the nosecone shoulder. I'll start off with 60 grit and report back.
 
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Did you try both ends of the airframe tube? Performance tubes have a slight taper for easier removal from the mandrel during manufacture. (only a few thousandths.) Mark the larger end, less sanding required.
 
Did you try both ends of the airframe tube? Performance tubes have a slight taper for easier removal from the mandrel during manufacture. (only a few thousandths.) Mark the larger end, less sanding required.

It wouldn't look as cool with the fins and NC on the same end
 
Is that why nose cones don't fit sometimes?? because of a taper on the tube I did a lot of sanding to get my Gizmo XL to fit.
GP
 
Is that why nose cones don't fit sometimes?? because of a taper on the tube I did a lot of sanding to get my Gizmo XL to fit.
GP

That could be a contributing factor..I had forgotten that the tube mandrels do have a slight taper to them..But most of it(especially the bigger 6"+ cones) is the hurried production of them(I think)..I don't want to sound overly negative but it does happen from time to time(the rush to get 'X' number of cones done in 'Y' amount of time- sometimes shortcuts are taken which leaves the parts a tad bit mis-fitting)...
 
Also to put things in proper perspective PR probably produced more kits than all the other manufactures combined, Having produced close to 3000! kits this year alone the number of cones that may require a bit of sanding is minuscule in comparison.
 
Also to put things in proper perspective PR probably produced more kits than all the other manufactures combined, Having produced close to 3000! kits this year alone the number of cones that may require a bit of sanding is minuscule in comparison.

Good point,,,, BUT if one cone didn't fit,,,, to the customer that got THAT cone,,,, it is all that matters

Tom
 
Also to put things in proper perspective PR probably produced more kits than all the other manufactures combined, Having produced close to 3000! kits this year alone the number of cones that may require a bit of sanding is minuscule in comparison.

I agree with this to some degree. That being said, I have been the "victim" of some of these quality issues, and they are quite bad. In order to make 3,000 kits, quality control is of the essence.

I was happy to see him cranking out the FWFG cones due to the repeatability. These large two part clam shell cones leave much to be desired in the larger sizes, especially when you're hustling to get a whole mess of them out the door.
 
Understood but with ANY manufacturers that produces any kind of quantity there WILL be some anomalies, SONY, Microsoft, GM ANY! of the big wigs have troubles from time to time.

All I'm saying is the other 99% of all PR nose cones that fit perfect! have to be recognized.


As for this thread and the GIZMO XL I'd rather talk about what people are going to stuff up its rump!

For the Jan MDRA launch I'm thinking either a CTI L990BS or the L640DT?
 
.


As for this thread and the GIZMO XL I'd rather talk about what people are going to stuff up its rump!

For the Jan MDRA launch I'm thinking either a CTI L990BS or the L640DT?
That sounds dirty. It all depends on if I get mine back from paint.


Tom
 
I understand the frustration that some have with part fitting on PR kits.

An often overlooked issue is this:

All these fiberglass kits, that before PR would have cost 2x what they do now, have become mainstream & are CHEAP for fiberglass.

We have all become addicted to them, we EXPECT flawless parts.... well it ain't gonna happen when price...price...price is the driving force.

The amount of product being pumped out at low cost is phenomenal, all of us "junkies" that need our fix has grown in leaps and bounds. To keep up with that demand AND keep the cost low requires some compromise.

Sure more employees can be hired, more molds made, more inventory kept on hand ,etc.etc but this would drive up cost considerably.

Mentioned earlier,compared to the amount of product being pumped out, the percentage of borderline things slipping by is fairly low.

We are supposed to be rocket scientists, When I began, cutting slots & trimming fins, beveling edges, filing,fitting and filling was pretty much the norm not the exception.

We have been spoiled by the "buy it,build it, fly it" simplicity these cheap kits have brought to the mainstream.
Heck you can now buy a L-3 and build it in a week if you wish. It hasn't been that many years ago this was a long drawn out process of design, cut, modify, glass it yourself ordeal. which usually took a year or more to accomplish, plus a TON of cash.

My L-3 project cost 980.00 just in the glass parts to get started and that was 10 years ago. Now you can have a completed kit/rocket with chutes, electronics etc for that.

So I say to you this: Where we we all be if PR were to disappear tomorrow off the planet?
Hmmmm didn't think of that huh? Where would economy class or for that matter most all fiberglass kits come from then. Where would we get our fix?

So go ahead and sharpen that needle yourselves, junkies can't get new ones at the pharmacy.

And if it's really THAT bad, where some elbow grease and time won't fix it, don't bitch about it, call your DEALER & let them take care of it. For sure they don't want you back out on the street getting your "fix" from someone else!:smile:
 
Well Said Jimmy, This thing called a "Winter Build" Doesn't exists in my world, With the way PR kits come now I can build a kit in 3-4 days tops! Hell I had 3 going at once last week alone.
 
Well said Jim!!!


....As for Gary, I have a few picked out: AMW L777, CTI L850,851 & M2250
 
My Gizmo XL came in today. The nose cone shoulder is not out of round. I have sanded a lot of the gel coat off already. It looks like I will need to sand off most of gel coat for it to work then reinforce inside of shoulder. Why does this happen.
Thanks
Gary

As a followup to my original post suggesting sanding the inside of the airframe tube using a large 3" diameter drum sander, I just finished doing this and it worked superbly well.

I started by hand sanding off the two opposing mold lines on the shoulder of the nosecone using 280 grit paper on a flexible sanding block. I did not sand any other part of the shoulder, leaving the shiny white gelcoat untouched. Next I used some 150 grit paper to form a slight chamfer on the inside edge of the airframe tube. This will help funnel the nosecone into the tube. Likewise I rounded over the nosecone shoulder's edge with 280 grit paper. I measured the shoulder length of the 8" diameter nosecone and used a felt pen to mark a reference line on the airframe. The sanding procedure inside the airframe would have to go a bit further than this mark to ensure no binding of the nosecone.

Next I placed the airframe in a cradle and chucked my 3" diameter x 3" long rotary drum sander into my variable speed drill with an 80 grit sleeve installed. I made an index mark where my sanding would begin at the bottom of the lip of the airframe tube. I began sanding the inside face of the tube with a slow side to side motion making sure the drum sander was making full contact from front to back so as not to cut grooves into the fiberglass. Without stopping the drill I pushed the sander in further to overlap the originally sanded area until I was just passed the index mark. Then I rotated the airframe tube about 15 degrees and repeated the same action; side to side and front to back. I did this over and over until I met the original index mark on the lip of the tube. This meant I had gone right around the complete interior of the tube. I test fitted the nosecone and it slide in much further than before. I repeated the complete procedure 2 more times and now the nosecone slid in all the way. I cleaned up the roughened, interior surface of the airframe by hand sanding using sandpaper wrapped around a flexible foam backing plate. I used 150 grit, then 220 grit. Finally I wet sanded using 400 grit including the chamfer on the airframe lip. I also used the 400 grit to clean up the area on the nosecone shoulder where the mold lines were previously sanded. The nosecone now drops right into the fuselage with minimal friction and no side to side play is detected when it is in all the way.

This method took about 30 minutes and saved HOURS of hand sanding the gelcoat on the nosecone and it's associated problems. (No messy and costly shoulder reinforcement using epoxy and glass needed.) Now I can epoxy in the nosecone's bulk plate making sure it is not so tight so as to deform the nosecone shoulder.

This method worked so well I may even try it on my smaller diameter builds instead of hand sanding nosecone shoulders. I picked up the 3" diameter sander at an ancient hardware store for $15.00 including 2 sleeves. I knew it was a deal so I grabbed it knowing I would find a use for it one day. It seemed huge at the time and weighs about a pound. The owner said it had been sitting there for at least 10 years and it was made in USA to boot! I also find it great for enlarging centering ring holes that are 3.5" and larger because it is easy to control because of its large diameter and mass. The second photo shows me enlarging a rough cut hole for a 4" glass tube that will go into my 8" nosecone.

I know that Sears has a similar sanders HERE. Rockler also has one HERE. Hope this helps some of you with tight fitting nosecones.

3 inch drum sander.JPG


Internal tube sanding.JPG


CR sanding.JPG


Gizmo XL nosecone fitted.JPG
 

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The way its going for me I may need to sand the tube also. I have most of gel coat sanded off the nose cone shoulder. Still to tight for me.
GP
 
Judging by the amount of glass removed from inside the tube, I too would EASILY have gone through the gelcoat. Cut your losses and sand the inside. There is LOTS of material on the 1/8" thick airframe tube. Look at the smooth shoulder on my nosecone.No sanding!

No sanding!.JPG
 
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