Quest Q-Jets

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Max liftoff weight cannot be simply listed by motor type ("C14").

It must be tied to delay time as well, as a shorter delay time will safely work with a heavier liftoff weight than a longer delay time.

And didn't they tweak the C14 to get the total impulse up to 10 N-s? I guess we'll know after certification testing.

The D is really a baby D at best, which is a bit disappointing. Still could be a useful little motor though.

The C seems nice, very comparable in most ways to the C11 although a little lower max thrust. The rated liftoff weight of 5 oz seems disproportionately conservative, dunno what's up with that.
 
Max liftoff weight cannot be simply listed by motor type ("C14").

It must be tied to delay time as well, as a shorter delay time will safely work with a heavier liftoff weight than a longer delay time.

And didn't they tweak the C14 to get the total impulse up to 10 N-s? I guess we'll know after certification testing.
Dunno, I'm just going by what's on the label above, which shows 9.3 N-s. Given they list the B liftoff weight at 4 oz, and the D at 10 oz, I don't see how they get 5 oz for the C, which is pretty close to the D performance-wise.

Anyway, all will become clear (I hope) when the Cs and Ds actually come to market.
 
The q-jet motors have more total mass not less.
Not according to their data table I included above, at least for the D series that I bothered to check - 25g claimed for their D16 vs 39.2-44.9g for Estes D12s.
 
Gents, sit tight for a couple days. I have the testing data, and am working on this. I expect to be done in the next couple of days.
 
The C14 and D16 are both now certified. For details see announcement in propulsion forum
 
E382ADCA-B0FB-455F-94F2-7E23D9C502EE.jpg6019E029-C2C4-4F1B-85B9-E27164A52B7D.jpgAFA4EA86-2F62-4529-9186-26282CB17310.jpg

Got some today...six days after a shipping notice with tracking... they look nice.
 
I got a chance to fly a few B 4-4 motors this weekend at NSL. I put one in a Quest Pulsar and another in an Estes Hornet. The Q-Jets worked flawlessly and put in respectable flights on both rockets. I'm looking forward to the new C and D motors, if they are anything like the new A's and B's, they should be lots of fun.
Thanks to Chris's' Rocket Supply for having a good supply on field this weekend.
 
Got my QJets yesterday. Apparently they were engineered to fit a Quest motor tube just fine. Problem is the Quest tube is slightly larger in ID than the standard BT-20 engine tube ( .747" vs .710"). So you will have to remove the label and the sticky adhesive with thinner or Goo Gone to pop it into a BT-20 or ST-7. A few other problems are expounded on at the thread in YORF. Hoping these issues are successfully addressed, I want to see these succeed!
 
Got my QJets yesterday. Apparently they were engineered to fit a Quest motor tube just fine. Problem is the Quest tube is slightly larger in ID than the standard BT-20 engine tube ( .747" vs .710"). So you will have to remove the label and the sticky adhesive with thinner or Goo Gone to pop it into a BT-20 or ST-7. A few other problems are expounded on at the thread in YORF. Hoping these issues are successfully addressed, I want to see these succeed!

I heard it through the grapevine at LDRS that the label is actually a structural part of the motor...
 
Got my QJets yesterday. Apparently they were engineered to fit a Quest motor tube just fine. Problem is the Quest tube is slightly larger in ID than the standard BT-20 engine tube ( .747" vs .710"). So you will have to remove the label and the sticky adhesive with thinner or Goo Gone to pop it into a BT-20 or ST-7. A few other problems are expounded on at the thread in YORF. Hoping these issues are successfully addressed, I want to see these succeed!

OH NO!!!!!!!!!!!!!!!
 
The label is just a sticker. And yes, to get these into a BT-20 the label and it's residue have to come off the motor. Even then, if the motor tube is dirty or squeezed by a centering ring or whatever, it won't go in. I have several older models that I'd wanted to fly on these that I can't get even a label-removed motor into.

With the label left on they are a snug fit in ST-7 but they can be gotten in there (and out again with the aid of a pair of pliers).

*sigh*

One also has to orient the ejection charge container (which is hex-shaped) so that a flat is in line with the upper tab on a motor hook to get them in. This just takes a bit of care.
 
One also has to orient the ejection charge container (which is hex-shaped) so that a flat is in line with the upper tab on a motor hook to get them in. This just takes a bit of care.

I've found that even with the flat of the hex oriented toward the hook, it will not fit get past the forward bend on some hooks. Tabbed engine hooks seem to be the most problematic, though there are some non tabbed hooks that don't work either. Depends on the length of the forward bend.
 
Got my QJets yesterday. Apparently they were engineered to fit a Quest motor tube just fine. Problem is the Quest tube is slightly larger in ID than the standard BT-20 engine tube ( .747" vs .710"). So you will have to remove the label and the sticky adhesive with thinner or Goo Gone to pop it into a BT-20 or ST-7. A few other problems are expounded on at the thread in YORF. Hoping these issues are successfully addressed, I want to see these succeed!

The label is just a sticker. And yes, to get these into a BT-20 the label and it's residue have to come off the motor. Even then, if the motor tube is dirty or squeezed by a centering ring or whatever, it won't go in. I have several older models that I'd wanted to fly on these that I can't get even a label-removed motor into.

With the label left on they are a snug fit in ST-7 but they can be gotten in there (and out again with the aid of a pair of pliers).

*sigh*

One also has to orient the ejection charge container (which is hex-shaped) so that a flat is in line with the upper tab on a motor hook to get them in. This just takes a bit of care.

Thanks, all, for the heads up. We have a low power launch tomorrow morning, and I was planning to burn the Q Jets.

I just went down and check a few of my BT20 models. I am 2 for 5, getting the motors in far enough that I'd be able to launch.

FWIW, I tried the motor in some pieces of BT20 from the parts pile. The BT20 from Aerospace Specialty products will take the QJet. label and all. In the other pieces -- some of which came from Estes kits, some from BMS, some from Apogee (maybe, don't know if I used up all the BT20 stock from that order) -- the motor either sticks before I get it all the way in, or it won't go in at all.

I am building a model with an 18mm motor mount right now -- I swapped out the motor tube for a piece of the ASP stuff that is (apparently) wide enough, and scrapped the engine hook.
 
I've found that even with the flat of the hex oriented toward the hook, it will not fit get past the forward bend on some hooks. Tabbed engine hooks seem to be the most problematic, though there are some non tabbed hooks that don't work either. Depends on the length of the forward bend.

Yes, I have seen the same in some of the models I tried yesterday after the Q-Jets I got from buyrocketmotors.com arrived.
 
Thanks, all, for the heads up. We have a low power launch tomorrow morning, and I was planning to burn the Q Jets.

I just went down and check a few of my BT20 models. I am 2 for 5, getting the motors in far enough that I'd be able to launch.

FWIW, I tried the motor in some pieces of BT20 from the parts pile. The BT20 from Aerospace Specialty products will take the QJet. label and all. In the other pieces -- some of which came from Estes kits, some from BMS, some from Apogee (maybe, don't know if I used up all the BT20 stock from that order) -- the motor either sticks before I get it all the way in, or it won't go in at all.

I am building a model with an 18mm motor mount right now -- I swapped out the motor tube for a piece of the ASP stuff that is (apparently) wide enough, and scrapped the engine hook.

Sounds like the ASP stuff is really ST-7 perhaps.

I have worked up an OpenRocket simulation of the ubiquitous Alpha III that is giving good results on all the motors I've actually tried in it and I was more than a little bummed to fine that I can't get the Q-Jets, even sans label, into it because the upper tang on the hook is a little too long. I will have to build another with an ST-7 motor tube and trim that upper tab to validate the numbers I already have for the Q-Jets therein.
 
I don’t get how they made these things to not fit in standard Estes mounts. I hope they correct this in the future, or at least for the C and D motors. Yeesh.
 
Sounds like the ASP stuff is really ST-7 perhaps.

The spec for T20 on the ASP website is exactly the same as the BT20 listed on the eRockets reference page -- 0.71 inch ID. Can't get a good ID measurement with my calipers (tube is too flexible), but the wall measures .03 mm thinner than the wall of the brown glassine Estes body tube -- so maybe that's the difference?

20180601_165709.png
 
The spec for T20 on the ASP website is exactly the same as the BT20 listed on the eRockets reference page -- 0.71 inch ID. Can't get a good ID measurement with my calipers (tube is too flexible), but the wall measures .03 mm thinner than the wall of the brown glassine Estes body tube -- so maybe that's the difference?

View attachment 345671

I'm guessing it might be a TT-20. Slightly larger than a T-20, it sleeve fits over the standard BT-20 tube. That would explain why the motor fits, label and all. Totally Tubular at erockets carries this as well.
EDIT: I checked the specs for the TT-20, it is virtually identical to the Quest motor tube. So that's what it probably is. You can confirm by seeing if an Estes BT-20 slide fits inside the ASP tube.
 
IMG_20180601_210939.jpgIMG_20180601_210904.jpgIMG_20180601_211325.jpg
Yes, I have seen the same in some of the models I tried yesterday after the Q-Jets I got from buyrocketmotors.com arrived.

The problem is they used the same design as Aerotech's RMS and SU motors, with the hex front cap (SU) or red plastic cap (RMS) for the ejection charge. If they had used the design of the old AT 18mm Ds, they wouldn't have had this problem: Simple cylinder with no hex cap, using a paper cap instead inside the casing to contain the ejection charge. ( See pics). No label on the casing, the engine type is identified on the ejection cap. Clean and simple, less things to go wrong. The red plastic ejection charge cap on the AT 18mm RMS motors hanging up on the engine hook is a known issue. yet here the problem is again with the new QJets.
 
I'm guessing it might be a TT-20. Slightly larger than a T-20, it sleeve fits over the standard BT-20 tube. That would explain why the motor fits, label and all. Totally Tubular at erockets carries this as well.
EDIT: I checked the specs for the TT-20, it is virtually identical to the Quest motor tube. So that's what it probably is. You can confirm by seeing if an Estes BT-20 slide fits inside the ASP tube.

In fact, this is how I knew this particular piece to 18mm tube was from ASP. It was sleeved inside a piece of TT20 in my parts box (I ordered the tube assortment about a year ago, when I made the BAR conversion).

The TT20, by the way, is too wide for a friction mount of the QJET.

It really is just the thickness of the label that make the difference for most of the tubes I tried. There are couple of built models, though, where the QJET is just never going to fit.
 
I don’t get how they made these things to not fit in standard Estes mounts. I hope they correct this in the future, or at least for the C and D motors. Yeesh.

I was pretty excited to try these. I ordered a few packs when they first became available back in March and just got my order yesterday. Unfortunately, like everyone else who has posted recently I cannot seem to get them into any of my Estes rockets; they don't even fit well into a few of my Quest models. I was only able to get it into 1 of my 3 18mm Quest kits. After struggling trying to get one of the B4-4s into a few rockets the decal on it was all torn and shredding, so like someone here mentioned I peeled off the label to see if it would fit then. Peeling the label just made a tremendous mess. There is an insane amount of incredibly sticky adhesive used on the backing of the stickers. After using GooGone to get rid of it, the naked B4-4 finally was able to slide into a few of my Estes and Quest rockets, but what a headache! I haven't even fired one of these Q-Jets yet, but I'm struggling to see the upside to these motors. Why would I want to have to peel labels and use GooGone on every motor to fly my rockets when I can just buy a comparable Estes motor and not have to deal with all this mess? Seems like a miscalculation to me by Quest/Aerotech. This will be the first and only batch I order unless this issue is addressed. :facepalm:
 
We had four of them used at our launch last weekend. I am not particularly impressed. They don't fit Estes rockets as they seemed to be sized for Quest tubes. Really? What were they thinking? We'll make something that will be difficult or impossible to be used in over 95% of 18mm rockets. Anyway, the labels had to be removed and even then it was a tight fit for one of the rockets. I've heard that they will sand down the cases in the future to provide a better fit.

Another issue was the shotgun ejection charges. Even at 500 feet or so the ejection charge was very loud and looked very energetic. One rocket was actually destroyed when the body tube blew apart along the spiral. The rocketeer sent photos to Quest of the destroyed rocket with an explanation of what happened. To be fair, we heard a number of Estes ejection charges that were just as loud.

The motors are quite smoky and loud if you like that sort of thing. I'm not going to run out and get any soon. If you want to use them I would recommend expendable rockets for now until they get a better handle on the ejection charges.
 
As i reported on YORF, I sent a direct message to Gary through Facebook Messenger (which I had never used before).
I provided the results of our first 4 A3-4 flights two weeks ago and he responded with a thank you for the feedback. I'm used to dealing with technical issues and explaining things so that the perceived issue is not just a complaint, but included the reason why it is an issue and also some suggestions for what might be a possible solution.

I pointed out that the A3-4 motors would only be used in very lightweight rockets, so they would not have a large volume to pressurize so the ejection charges seemed to be very strong. Ditto for an A3-6 motor which would only be used in an even lighter rocket.

he responded right away that they would look at reducing the ejection charges (IIRC from .5 grams to .3 grams). Also, the future motors would be .005 inches smaller diameter. I also had reported that the taping of the initiator was an issue since the tape can hold the wires and either the wires will be carried up (not good on low thrust motors) or the rocket would stay on the pad if the clips did not release from the wires. The solution for that was to now use 3/64" heat shrink installed next to the initiator in the nozzle to act as the 'plug' to hold it in, while still providing venting during ignition.

We tried the 3/64" heat shrink last weekend with 3 B4-4 launches and it worked great. We are 7 for 7 with ignition (4 x A3-4 and 3 x B4-4). We provided additional feedback for these latest flights and Gary confirmed that they are already using the .3 gram ejection charges for the motors being produced now. I did not ask for date codes, nor did I ask when the diameter change will cut in.

The B4-4 ejection charges were also strong, so the reduction will be welcomed. We also had a Big Bertha which hit the ground before ejection on a B4-4. The Big Bertha was stock with a small altimeter installed and it boosted fine to an acceptable altitude (I did not get the reading from the model owner), but the delay was at least 6 seconds and that was too long. All 3 of the B4-4 motors flown had long delay times, so either they are running long or they were B4-6 motors mislabeled.

So, for now, we will use the current batch of motors in lightweight rockets, with very strong shock cords and we will peel the labels and use the 3/64" heat shrink.

Gary responded to the last report to confirm that they were revising the instructions to provide max liftoff weights for each motor and delay time, which is locigal since a long delay would only be used in a lighter model. Also, they are officially adding the heat shrink to the motor packs and the instructions.

Continuous improvement and listening to useful (helpful) feedback. That is good.

As I told him, there are a lot of us who will be buying bulk packs (many bulk packs) once the issues are resolved.

So, if you have any issues, just send a report to their customer service e-mail contact. It will get the correct people.

We had four of them used at our launch last weekend. I am not particularly impressed. They don't fit Estes rockets as they seemed to be sized for Quest tubes. Really? What were they thinking? We'll make something that will be difficult or impossible to be used in over 95% of 18mm rockets. Anyway, the labels had to be removed and even then it was a tight fit for one of the rockets. I've heard that they will sand down the cases in the future to provide a better fit.

Another issue was the shotgun ejection charges. Even at 500 feet or so the ejection charge was very loud and looked very energetic. One rocket was actually destroyed when the body tube blew apart along the spiral. The rocketeer sent photos to Quest of the destroyed rocket with an explanation of what happened. To be fair, we heard a number of Estes ejection charges that were just as loud.

The motors are quite smoky and loud if you like that sort of thing. I'm not going to run out and get any soon. If you want to use them I would recommend expendable rockets for now until they get a better handle on the ejection charges.
 
As i reported on YORF, I sent a direct message to Gary through Facebook Messenger (which I had never used before).
I provided the results of our first 4 A3-4 flights two weeks ago and he responded with a thank you for the feedback. I'm used to dealing with technical issues and explaining things so that the perceived issue is not just a complaint, but included the reason why it is an issue and also some suggestions for what might be a possible solution.

I pointed out that the A3-4 motors would only be used in very lightweight rockets, so they would not have a large volume to pressurize so the ejection charges seemed to be very strong. Ditto for an A3-6 motor which would only be used in an even lighter rocket.

he responded right away that they would look at reducing the ejection charges (IIRC from .5 grams to .3 grams). Also, the future motors would be .005 inches smaller diameter. I also had reported that the taping of the initiator was an issue since the tape can hold the wires and either the wires will be carried up (not good on low thrust motors) or the rocket would stay on the pad if the clips did not release from the wires. The solution for that was to now use 3/64" heat shrink installed next to the initiator in the nozzle to act as the 'plug' to hold it in, while still providing venting during ignition.

We tried the 3/64" heat shrink last weekend with 3 B4-4 launches and it worked great. We are 7 for 7 with ignition (4 x A3-4 and 3 x B4-4). We provided additional feedback for these latest flights and Gary confirmed that they are already using the .3 gram ejection charges for the motors being produced now. I did not ask for date codes, nor did I ask when the diameter change will cut in.

The B4-4 ejection charges were also strong, so the reduction will be welcomed. We also had a Big Bertha which hit the ground before ejection on a B4-4. The Big Bertha was stock with a small altimeter installed and it boosted fine to an acceptable altitude (I did not get the reading from the model owner), but the delay was at least 6 seconds and that was too long. All 3 of the B4-4 motors flown had long delay times, so either they are running long or they were B4-6 motors mislabeled.

So, for now, we will use the current batch of motors in lightweight rockets, with very strong shock cords and we will peel the labels and use the 3/64" heat shrink.

Gary responded to the last report to confirm that they were revising the instructions to provide max liftoff weights for each motor and delay time, which is locigal since a long delay would only be used in a lighter model. Also, they are officially adding the heat shrink to the motor packs and the instructions.

Continuous improvement and listening to useful (helpful) feedback. That is good.

As I told him, there are a lot of us who will be buying bulk packs (many bulk packs) once the issues are resolved.

So, if you have any issues, just send a report to their customer service e-mail contact. It will get the correct people.

And please file MESS reports whenever a delay is incorrect.
 
I flew my ARS Patriot on a Quest A3-4 just for some afternoon fun.
It had a great boost, but when it came time for the ejection charge, it was very loud, and both my brother & I said at the same time, WHOA! My rocket separated into 4 pieces. my streamer landed around 1/4 mile away, and thankfully someone found it & game me a call!
The booster fell very hard into the grass, but no damage there.
The nose cone separated into 2 pieces, the nose cone insert seperated and fell into the parking lot, which is pretty much a miracle we found that.
AND, the nose cone fell so hard, it cracked!
So, yeah these motors have too much BP in them. I contacted Quest/AT/RCS and they told me that they put .5 grams of BP in the Q-Jet motors. They said they'll reduce the amount to .3 grams for the second batch. I do understand that this was kinda a "experimental batch" This after all was their first batch out to the public, and they wanted feedback, and I'm sure they'll fix these problems for the second batch.
NOT happy with these motors.
Here's the video: [video=youtube;0Xl8W7m3v1U]https://www.youtube.com/watch?v=0Xl8W7m3v1U[/video]
And, the label is a pain to peel off, but after that, it did fit well into the body tube, and came out just fine.
photo.JPGphoto(1).JPG

I'm now scared to fly anymore of my Q-Jet motors.


I won't be buying these until the ejection charge problem is fixed.




Thanks,
 
I also had reported that the taping of the initiator was an issue since the tape can hold the wires and either the wires will be carried up (not good on low thrust motors) or the rocket would stay on the pad if the clips did not release from the wires. The solution for that was to now use 3/64" heat shrink installed next to the initiator in the nozzle to act as the 'plug' to hold it in, while still providing venting during ignition..

Yes, this is what happened with all three of my attempted Q-Jet launches last Saturday. Two attempts with a B4-6 in a Skyhook clone (built light) never left the pad. I thought the first one might have gotten hung up on a dirty rod. Video of the second attempt revealed that it was being held down by the leads taped to the engine casing. Tried again with an A3-6, with the tape across the nozzle. If got airborne, but only just. It was slow off the rod, and hit the ground before the (very loud and very hot) ejection charge.

I've contacted Quest through their website. Awaiting a reply.
 
If folks have motors without the 3/64" heat shrink, you can simply support the initiator with a clothespin and lower the model onto the initiator with no use of tape. Similar to the MicroMaxx igniter support.

And keep those models LIGHT.

As for the ejection charges, all I can say (until the new batches are shipped) is to have very long and strong shock cords. adequate wadding (not packed too tightly or it will become a 'bullet') and ensure your nose cone is not too tight.


Yes, this is what happened with all three of my attempted Q-Jet launches last Saturday. Two attempts with a B4-6 in a Skyhook clone (built light) never left the pad. I thought the first one might have gotten hung up on a dirty rod. Video of the second attempt revealed that it was being held down by the leads taped to the engine casing. Tried again with an A3-6, with the tape across the nozzle. If got airborne, but only just. It was slow off the rod, and hit the ground before the (very loud and very hot) ejection charge.

I've contacted Quest through their website. Awaiting a reply.
 
If folks have motors without the 3/64" heat shrink, you can simply support the initiator with a clothespin and lower the model onto the initiator with no use of tape. Similar to the MicroMaxx igniter support.

And keep those models LIGHT.

As for the ejection charges, all I can say (until the new batches are shipped) is to have very long and strong shock cords. adequate wadding (not packed too tightly or it will become a 'bullet') and ensure your nose cone is not too tight.

I'm glad to see that they're trying to address the engine diameter, ejection charge, and igniter retention issues. I still haven't given up on these, and will wait and see how the fixes turn out. However, I don't see anything mentioned about the engine hook clearance issue. Specifically, the front end hex cap not clearing the forward bend of the engine hook on some types. This will not be an easy fix: they will have to shrink the hex cap, or eliminate it entirely. Then I'm wondering if it needs to be recertified. Comments?
 
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