My Madcow Tomach (Money Burner)

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Looks good Kyle! Sounds like you're doing the Vern-style nosecone anchors? I usually recommend these so you can use your nosecone as a tracker/GPS bay, like you mention.

I've never tried using threadlocker on a nosecone tip - but I've also never had occasion to remove one EXCEPT if I'm using it as a shockcord attachment point, such as in my 3" MD. Drogue chute looks good!
Are you using a MissileWorks sled? I see you're using their screw switches, much like myself. :) I slightly prefer the Featherweight screw switches (a lot smaller) but the MissileWorks ones are a bit cheaper.

What are your screws tapped into?

Your vent holes will probably be fine, but for extra insurance I'd add a few more on the other side of the bay.

The altimeter sled is actually one directly from Landru. He also produces the Missleworks sleds for them. The screw switches were also ordered from Landru, as the sled is made to mount hold them.

The screws for the Aeropack retainer are tapped into the retainer itself, which should work fine as there is no load trying to strip them out. The screws for the av-bay are tapped into the fiberglass, and two of them have nuts epoxied on the inside. the third one will just tap into the fiberglass, as the screw switch is right behind it. I will insert it after arming the electronics at the pad. Here are two pictures of the nuts in the av-bay:
20150402_161133.jpg 20150402_161126.jpg

Hope theses help: I have a 6gxl case too and the biggest motors are cool. If I heard u right: vent holes should not be placed below any protrusions. It can mess up readings. I read this in one of the AV bay instructions, or the missile works instructions, or the rocket book. You probably used the formula for av bay vent sizing, right? I have used the Eggfinder TX and just got TRS. The instructions seem a little confusing, you might want to look up a couple of threads on this forum. One guy had a problem turning it on at the pad.

I did use the calculations to find the correct size for the vent holes. And I also changed how the vent holes are placed. They are now located in between the bolts, and one of the bolts is removable for to arm the altimeter.

https://m.youtube.com/watch?v=C2IKh840XFk
Just a thought, I used a small motor to test out the ejection charges & electronics prior to going out of sight with a large motor. In the flight attached video, I would have lost it if the gps EggFinder didn't work :(

I had planned on using a full G motor for the test flight, but it will be too heavy, except for the G339, which I am not certified for yet. To test the electronics, I am taking my foodsaver to the launch to do a vacuum test of both altimeters together after I pick up my StratologgerCF. I am then planning on testing the electronics in my Madcow Scooter, as I am making it so the av-bay switches over. I will be ejecting the main at apogee with a long motor delay backup, and just popping the nose cone at 500 feet. Once this is all confirmed, I will put it in my Tomach and go for my L1.

Wow Kyle, it is looking great, love the 3D printer altimeter sled. I have 2 of those for other builds so it's nice to see what others have done with theirs.

As far as the vent holes I will repeat the advice I was given when I asked a similar question. In general you want to keep the vent holes away from anything that can disturb or break the laminar airflow. Having said that you may be fine, but I would try a test flight with engine backup for the apogee event as this is primarily when it will be an issue. I used that approach when I put vent holes in a nosecone and the back up was not required because it went off without any issues.

Thanks for the kind words! The 3d printed sled is really nice, especially the 9v battery compartment, as it fits two of my lipos securely. I managed to do a little more wiring today, although I will have to finish it at the launch when I get my Stratologger. I moved the vent holes so they would not be downstream of any obstructions, as mentioned at the beginning of this post. As for the test flight, I can't use motor backup because the Aeropack minimum diameter retainer is not ported, and I need to use a tapped forward closure.

That just reinforces my thoughts on drogue vs drogueless.

Are you for or against a drogue chute? Or are you using a streamer since you asked about a reflective one in another thread? Do you have any photos of yours? All I have seen is the av-bay.


I managed to get a lot done today, so it is looking like I will be ready for Saturday! I epoxied in the nose cone coupler using Proline 4500, tied up both shock cords, drilled the vent holes, did more wiring on the electronics, and managed to cram the drogue chute/protector and shock cord into the small space it has been given. Does anybody know if there should be room left between the ejection charge and the chute protector? As it is now, I have to push in the last 1/2" and have the shear pins hold it together. Here is a picture of the nose cone coupler epoxied in:
20150402_161237.jpg

The list is still shrinking!
To do still:
Wire up altimeter bay
Ground test
Make retainer extension

I plan on finishing the wiring at the launch. I am also taking my dremel and the all-thread to make the extension at the launch as well. I can't do the ground testing at home, as I don't have igniters that work (I only have estes igniters), so that will have to wait until Saturday morning as well. All I have left to do tomorrow is a few thing on my Madcow Scooter, try packing the main chute, and smoke some tri-tip. :cool:

Until tomorrow,
Kyle
 
Good luck on it's maiden flight! But remember you can always wait until the next launch if there is not enough time to finish it. I have had a couple of failures because I rushed on those projects, but I have learned my lesson. One thing I would recommend is using PEM nuts (self-clinching) I use them as a mount for my rail buttons and AV-bays.
 
Last update until hopefully an update saying I am L1 certified. Didn't do much today, just a few small things. I made the blast deflector for the launch tower and adjusted it, updated the firmware for the TRS and LCD receiver, make a rocket hanger, did a little more wiring, etc. I also called Mike at BAR, and he hasn't received his order from Perfectflite yet, so the backup altimeter is now going to be an Altus Metrum Easymini. Now I just have to go get a few hours of sleep and then wake up to finish packing.

Wish me luck for my L1!

Thanks for following along this far,
Kyle
 
Well I didn't get to launch it yesterday. I got to the launch site and picked up my Easymini from BAR, along with the tapped closure and a perfectflite firefly. I got to work making the motor extension using allthread and a dremel I brought with me, and then did the soldering to get the easymini wired up and programmed it with my laptop. Once I got that done, I helepd my little cousin and my uncle get their rockets ready, as they were using midpower motors for the first time. After that I got some igniters from Qquake2k for the flight and ground tests (Thanks Qquake2K!). Before I could do the ground tests, I helped my friend get his L1 rocket ready, a Madcow 2.6" Patriot flying on a CTI H133. Once he got his L1, I got Watermelonman to watch me assemble the charges since I had never done it before to make sure I didn't mess it up (Thanks Watermelonman!). The ground testing went good, with 1g for the main and .5g for the drogue. I will put up the video of it later today. After the ground testing, I set up the launch tower and started to assemble the rocket for flight, but by that time it was nearing 4:00, when the waiver would end. I had a problem getting the delay grain to go all the way into the plugged closure, so I went to see Marcus at BAR to get his advice, and then he watched me assemble the motor. After that I was rushing to get it all ready, with my whole family helping me however they could. By the time I got it assembled and was sprinting down to the high power check in, it was 4:02, which was too late.

So now I am planning to go to the Reno launch on the 26th, and will hopefully get my L1 there. I will be sure to get started early, since I now have everything I need and don't need to do any last minute fabrication/soldering/ground testing.

I'll put up some pictures of me assembling the rocket and videos of the ground tests later today.

Happy Easter,
Kyle
 
Too bad, now you will have time at next launch to set it up calmly and enjoy it. Good luck.
 
Missed the window by 2 minutes - bummer...very sorry to hear this. :( I've been there before so I know what it's like, having all your chips in 1 barrel then having to turn around and go home empty handed.
Look forward to seeing the photos if you've got them...
 
Too bad, now you will have time at next launch to set it up calmly and enjoy it. Good luck.

Yep, and now I know how long it takes and can plan accordingly.

Missed the window by 2 minutes - bummer...very sorry to hear this. :( I've been there before so I know what it's like, having all your chips in 1 barrel then having to turn around and go home empty handed.
Look forward to seeing the photos if you've got them...

I'll have photos of assembly later, as they are on my aunt's camera, but here are videos of the ground tests:
Main with 1g: [video]https://youtu.be/nZRTHCURBdM[/video]

Drogue with .5g: [video]https://youtu.be/zFIxS7i77e4[/video]

Cheers,
Kyle
 
Are you for or against a drogue chute? Or are you using a streamer since you asked about a reflective one in another thread? Do you have any photos of yours? All I have seen is the av-bay.
Kyle

Hi Kyle,

Watched your ground testing, looks like it went off without any issues at all. I don't recall what size shear pins are you using?

I am in the for drogue camp. Not that I wold never go drogueless, as I could build a rocket that may call for it but so far I have used drogues. The streamer is totally new to me and I am still trying to wrap my head around it. I like the idea of the reflective qualities that some of the streamers have. My concern is that it does not create enough drag to keep the nosecone slightly higher than the booster. So I have purchased a couple of reflective ones and plan to try them whenever appropriate. For me, in an ideal world I would want something reflective at apogee, that creates just enough drag to keep the nose/main higher that the booster, but does not add so much CD that it has a marketable effect on the decent.

For some reason the upload button does not appear when I browse to a pic for upload so I cannot upload right now. I will tray again later to post some pics.
 
Hi Kyle,

Watched your ground testing, looks like it went off without any issues at all. I don't recall what size shear pins are you using?

I am in the for drogue camp. Not that I wold never go drogueless, as I could build a rocket that may call for it but so far I have used drogues. The streamer is totally new to me and I am still trying to wrap my head around it. I like the idea of the reflective qualities that some of the streamers have. My concern is that it does not create enough drag to keep the nosecone slightly higher than the booster. So I have purchased a couple of reflective ones and plan to try them whenever appropriate. For me, in an ideal world I would want something reflective at apogee, that creates just enough drag to keep the nose/main higher that the booster, but does not add so much CD that it has a marketable effect on the decent.

For some reason the upload button does not appear when I browse to a pic for upload so I cannot upload right now. I will tray again later to post some pics.

I think the ground testing went well. I might go to .6g for the drogues, just to get a little more separation. The backup charges will be +20% of the primary charges, just to be sure it separates if something goes wrong. The shear pins I am using are 2-56 nylon screws, and there are three of them in each section.

Be sure to let me know how the streamer works out for you, as I have been thinking of ways to add something reflective to my drogue to maybe be able to track it visually. I was considering small strips of mylar around 6" long tied to multiple points on the shock cord.

I still unable to upload but here is a previously uploaded pic of my 54mm MD carbon fiber Tomach beside another CF build I have on the go, a 38mm MD Performance Rocketry Mongoose.

View attachment 260160

Looks good! I take it you like CF kits over fiberglass? When do you think it will have its maiden flight? And did you make those rocket stands? Those look awesome for displaying rockets vertically.

They way I have found to get around the attachment issue is to go to manage attachments, then upload and insert inline. That way has been working for me, but the usual way hasn't.

Cheers,
Kyle
 
I think the ground testing went well. I might go to .6g for the drogues, just to get a little more separation. The backup charges will be +20% of the primary charges, just to be sure it separates if something goes wrong. The shear pins I am using are 2-56 nylon screws, and there are three of them in each section.

I plan on starting my ground testing in a couple of weeks. I originally drilled out my shear pin holes and tapped them for 4-40 but I think based on what I am reading that this may be a bit too much. So I just ordered some 2-56 PEM nuts to install on the back of the holes inside the AV bay.

Be sure to let me know how the streamer works out for you, as I have been thinking of ways to add something reflective to my drogue to maybe be able to track it visually. I was considering small strips of Mylar around 6" long tied to multiple points on the shock cord.

Yes I have thought about it a bit as well as scoured the form and streamers don't seem to have a lot of traction in HPR although I believe they have the potential. I have two on order, one from Pat @ Dino Chutes, the other soon to be on order from Gary @ Top Flight. Pat's is highly reflective but it has to be rolled and because of the edging it packs close to the entire inside diameter of the tube @ 120" long. So I am not sure if this one will be a candidate for this rocket but it will for my 3" Dark Star, which I also want to launch on the Loki L-1040 so visual tracking would be of interest. Incidentally the visual tracking is not necessary as I will have dual trackers in both rockets, it is just a preference and give me some comfort.

Looks good! I take it you like CF kits over fiberglass? When do you think it will have its maiden flight? And did you make those rocket stands? Those look awesome for displaying rockets vertically.

Well not really, with the new thin walled FG, for most applications I see CF as a disadvantage simply because it is more expensive and has blocking qualities for RF. Working with CF and FG is similar however the CF can get very messy as the carbon when ground into a fine powder gets into everything including your fingertips takes a bit to wash out. Beyond that working with it from an epoxy point of view is not much different to me nor has the small amount of layups I have done, including some vacuum bagging. But my experience in that realm is very limited.

I am planning a checkup launch for NYPOWER possibly on an I599P, just a blip off the tower to 2500" enough to get some testing of my deployment system, see how the drogue or streamer performs etc. The current plan is to use it for my L2 at LDRS, however because I am going to such an extreme in alt and velocity (20k @ Mach 2, + or -) I felt it would be best to do at least one check out launch.

The way I have found to get around the attachment issue is to go to manage attachments, then upload and insert inline. That way has been working for me, but the usual way hasn't.

Yes I tried that yesterday but no luck, that is when I saw that I had the pic that I previously posted of the two CF builds and re-posted it to your thread. Not sure what the issues is but there is most definitely an intermittent upload issue going on with the forum. I was just able to do the manage attachment upload now, here is a pic of my titanium nosecone tip.

View attachment 260218

Yes I said titanium and yes I know a bit overkill but I had to replace the stock one due to an accident that could of killed me. I was putting the rocket on the scale, and the nosecone coupler was just hand pushed in, and while on the scale the coupler slid off and the nosecone fell pointy end down from 77". It just missed the back of my head by an inch and completely flattened the tip. Scared the hell out of me...would of made a great headline though. So I figured if I was going to make anohter one I may as well do it in a harder material. Plus these tips are interchangeable, so I can swap it with the 3" nosecone tip on my Dark Star or 3" Pain Killer.
 
And did you make those rocket stands? Those look awesome for displaying rockets vertically.

I just remembered that you asked about the stands. They were CNCd by Nat AKA Wingarcher. They are surprisingly sturdy and he has me sets from 24mm to 54mm, but I see no reason they couldn't be scaled up or even down to suite your needs. I just had him cut some 24mm with an extra long center post for my BadAzz mini-missile line. The mini-missiles have aluminum CNCd centering rings and no MMT, so you need to span the distance from one ring to another, otherwise the rockets flop around on the center post.
 
I
Yes I tried that yesterday but no luck, that is when I saw that I had the pic that I previously posted of the two CF builds and re-posted it to your thread. Not sure what the issues is but there is most definitely an intermittent upload issue going on with the forum. I was just able to do the manage attachment upload now, here is a pic of my titanium nosecone tip.

View attachment 260218

Yes I said titanium and yes I know a bit overkill but I had to replace the stock one due to an accident that could of killed me. I was putting the rocket on the scale, and the nosecone coupler was just hand pushed in, and while on the scale the coupler slid off and the nosecone fell pointy end down from 77". It just missed the back of my head by an inch and completely flattened the tip. Scared the hell out of me...would of made a great headline though. So I figured if I was going to make anohter one I may as well do it in a harder material. Plus these tips are interchangeable, so I can swap it with the 3" nosecone tip on my Dark Star or 3" Pain Killer.

Wow, titanium. How hard was it to make that? It looks good!


I don't have any updates for my build at the moment. I am looking forward to the 26th at Reno Rocketry for my L1. After that I will try to get the T2T done before Dairy Aire, so I can return the vacuum pump I borrowed, and have it ready for my L2 at Mudroc (Hopefully).

Speaking of going for my L2, even though I might be getting ahead of myself, I am trying to decide what motor to use. I am debating between the CTI L935 and the L265. The L935 would be nice for max altitude, and was my original choice, but watching videos of the L265 has me considering it. The 9 second burn just looks so awesome! Any input on which of the two motors I should use? Both motors should break 20k, which is my goal.

Cheers,
Kyle
 
Wow, titanium. How hard was it to make that? It looks good!

Yeah I know it's a bit overkill, but I can move it from nosecone to nosecone and it is hard. My machinist had to get a special tap as his regular tap would nut cut it, figuratively and literally. He actually ended up making me two because he picked up the material just for me and the material was the more expensive part. The other one is a bit more rounded as it wasn't quite enough to make the same length but it looks great on my 3" kits, like the Pain Killer and Dark Star.

I don't have any updates for my build at the moment. I am looking forward to the 26th at Reno Rocketry for my L1. After that I will try to get the T2T done before Dairy Aire, so I can return the vacuum pump I borrowed, and have it ready for my L2 at Mudroc (Hopefully).

I was just working on my vacuum press last night. Another TRF member gave me this link https://www.joewoodworker.com/veneering/EVS/concept.htm It is from Joe Woodworker and he has a very nice vacuum pump design that is auto-cycling. Here is a pic of mine taken last night, it is further along than the pic, should be complete in the next couple of days, if I can find the plumbing fittings.

View attachment 260779

Speaking of going for my L2, even though I might be getting ahead of myself, I am trying to decide what motor to use. I am debating between the CTI L935 and the L265. The L935 would be nice for max altitude, and was my original choice, but watching videos of the L265 has me considering it. The 9 second burn just looks so awesome! Any input on which of the two motors I should use? Both motors should break 20k, which is my goal.

Cheers,
Kyle

The only motor I have been able to reliably simulate to 20K is the Loki L-1040, which is what I am Launching at LDRS. The L935 and L265 both simulate just shy of 18K for me. I am using RockSim and always simulate with higher than expected environmental conditions as far as winds and turbulence is concerned, temp and humidity I try to get based on norms and I adjust everything right up to the launch. So far my sims have been surprisingly accurate, except for one where I was way off by about 40% but that had a design characteristic that I believe RockSim was not able to correctly simulate.

Have you simed your Tomach on those two motors, what are you getting? BTW is your booster the same as mine 42"? Here is a pic of mine from RockSim with the L-104 loaded. This gives you an idea of space, the grid is a 1" and from the top of the Aeropack to roughly where my blast caps are is about 5.5". This is not a lot of room for my recovery gear, which literally wants to force the rocket apart by about .25", but thankfully it does not require a lot of force to keep it flush.

View attachment 260778
 
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I was just working on my vacuum press last night. Another TRF member gave me this link https://www.joewoodworker.com/veneering/EVS/concept.htm It is from Joe Woodworker and he has a very nice vacuum pump design that is auto-cycling. Here is a pic of mine taken last night, it is further along than the pic, should be complete in the next couple of days, if I can find the plumbing fittings.

View attachment 260779

I borrowed a vacuum pump from a member of my club. He made it from a vacuum desoldering station and an air tank, and says it will pull 18" of vacuum and automatically shut off and turn back on to keep it.

The only motor I have been able to reliably simulate to 20K is the Loki L-1040, which is what I am Launching at LDRS. The L935 and L265 both simulate just shy of 18K for me. I am using RockSim and always simulate with higher than expected environmental conditions as far as winds and turbulence is concerned, temp and humidity I try to get based on norms and I adjust everything right up to the launch. So far my sims have been surprisingly accurate, except for one where I was way off by about 40% but that had a design characteristic that I believe RockSim was not able to correctly simulate.

Have you simed your Tomach on those two motors, what are you getting? BTW is your booster the same as mine 42"? Here is a pic of mine from RockSim with the L-104 loaded. This gives you an idea of space, the grid is a 1" and from the top of the Aeropack to roughly where my blast caps are is about 5.5". This is not a lot of room for my recovery gear, which literally wants to force the rocket apart by about .25", but thankfully it does not require a lot of force to keep it flush.

View attachment 260778
I am using Openrocket because it is free, but I might try the Rocksim 30 day trial before my L2 just for another sim. I am using the stock simulation weather settings, but will adjust it at the launch. Looking at your screenshot, it looks like your rocket is over 1kg heavier then mine. My ready to fly weight without the motor is 4.5 lbs. I will also be using the CTI tapered rear closure, which adds about 1000ft.
Here is a screenshot of my sim with different motors:
Capture.jpg
Note that the weight is a little off, as I have yet to weigh all the individual components, but it is off by less then 50g.

And the booster for the fiberglass version is only 36", with a 66" total length. That just means mine is even more cramped then yours, and without shear pins it would not stay flush. (using a 48" main chute and a 20ft harness for both chutes doesn't help).

Cheers,
Kyle
 
I am using Openrocket because it is free, but I might try the Rocksim 30 day trial before my L2 just for another sim. I am using the stock simulation weather settings, but will adjust it at the launch. Looking at your screenshot, it looks like your rocket is over 1kg heavier then mine. My ready to fly weight without the motor is 4.5 lbs. I will also be using the CTI tapered rear closure, which adds about 1000ft.
Here is a screenshot of my sim with different motors:
View attachment 260782
Note that the weight is a little off, as I have yet to weigh all the individual components, but it is off by less then 50g.

And the booster for the fiberglass version is only 36", with a 66" total length. That just means mine is even more cramped then yours, and without shear pins it would not stay flush. (using a 48" main chute and a 20ft harness for both chutes doesn't help).

Cheers,
Kyle

Yeah the Loki L-1040 total weight is 2962g according to ThrustCurve, which is about 420g more grams than the CTI L935. It is a bit surprising on the total weight considering its carbon fiber and I don't have my typical 5lbs of paint and bondo...it is pretty bare bones except what is required.

I am going to convert RockSim file over to OpenRocket this evening, should be interesting.

I am also using a 48" main and 20' recovery harnesses, as well as a 15" drogue.
 
Well that is interesting and a bit concerning. I just installed OpenRocket on my Mac, imported my RockSim Tomach simulation, it didn't like the spill holes in my chutes, however after I downloaded the latest RASP file for the Loki L-1040 and ran the simulation, the numbers I am getting are quite a bit different. According to OR it sims to 24,800' @ Mach 1.91...RS sims to 20,300' @ Mach 1.81. That is a significant difference.

I recall reading some threads about a year ago where several people commented that OR is more accurate in the higher Mach numbers than RS. What I don't know is if this is still the general consensus and what is considered high Mach?
 
Well the launch I planned to go to in Reno got rained out. Of course during the drought it rains the week before the launch, which cause there to be too much water on the lake bed. So now I will attempt my L1 at Dairy Aire.

As for updates to the build, I've just been gathering supplies to do the T2T. I placed an order with ACP composites yesterday for all of the vacuum bagging materials, which should arrive tomorrow. I ordered Proline 4500 from Rocketry Warehouse last week, and I bought one yard of carbon fiber from a Lunar club member who lives close to me this evening. Once I receive my order tomorrow, I will probably start making the templates to cut the CF on Friday, and work on actually doing the T2T next week.

In my order form ACP I also added two yard of 2oz fiberglass to practice with before doing the CF. I am building two crayon rockets for Dairy Aire, one of which will be made specifically for the night launch, and I am planning on applying a layer or two of fiberglass to the fins as practice for the T2T. I also have a BMS School Rocket that is extra from teaching rocketry at my old middle school, so I am going to fiberglass it and turn it into a 24mm minimum diameter rocket. I should have plenty of practice by the time I do the T2T.

Look forward to another update in the next few days.

Cheers,
Kyle
 
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Glad to hear that one of us is making progress on our Tomachs... I just moved and haven't set up my rocket shop yet. I was really hoping I could have my rocket ready for a test flight (meaning fly the longest ass-kicking 54mm motor as possible in it, and see what happens) at our May launch, but I'm fairly sure that will get pushed ahead to NXRS. When is DairyAire?
 
I flew a MD FG rocket on the L935 and got ~27kft from "sea level". I mention this because it was a standard PR NC & AF (albeit with a high TG) but I purchased the Tomach fins from Madcow and used them. So in a way it was like a modified Tomach lol.

Here is the original thread of the build/flight: https://www.rocketryforum.com/showthread.php?66815-Progress-Minimum-Diameter-54-(CTI-L935)

Anyways good luck with your flights.

I have read through your thread many times. I wish I had access to machining equipment like you do. In the future I may see if I can get a new motor retainer made similar to yours so I can fit the Loki 54/2800. The L1040 is calling my name, although I would have to fly it in Black Rock (stupid California laws).

Glad to hear that one of us is making progress on our Tomachs... I just moved and haven't set up my rocket shop yet. I was really hoping I could have my rocket ready for a test flight (meaning fly the longest ass-kicking 54mm motor as possible in it, and see what happens) at our May launch, but I'm fairly sure that will get pushed ahead to NXRS. When is DairyAire?

I like your idea for the "test flight" :cool: What motor are you planning on using?

Dairy Aire is May 15-17, so I have about two weeks to finish the T2T. I'm not sure yet whether I am going to paint it by Dairy Aire, or make it earn its paint, lol. If you are still planning on maybe going to XPRS, we should drag race. Minimum diameter K2045 drag race perhaps?

Cheers,
Kyle (who is currently patiently waiting for the UPS man)
 
I have read through your thread many times. I wish I had access to machining equipment like you do. In the future I may see if I can get a new motor retainer made similar to yours so I can fit the Loki 54/2800. The L1040 is calling my name, although I would have to fly it in Black Rock (stupid California laws).

Can you not fly with FAR? They allow 50kft and up to O motor with the "standard," 8 days prior request and for anything larger/higher you have to go through the FAA. I know they have recently had a static Q motor out there, so I am not to sure about the Cal laws...

I would just friction fit the motor. It adds less mass, takes up less space, no added drag, and it works.
 
Can you not fly with FAR? They allow 50kft and up to O motor with the "standard," 8 days prior request and for anything larger/higher you have to go through the FAA. I know they have recently had a static Q motor out there, so I am not to sure about the Cal laws...

I would just friction fit the motor. It adds less mass, takes up less space, no added drag, and it works.

The problem isn't with the waiver or motor size. California requires all commercial motors to be approved by the State Fire Marshall. This requires a $1500 per year license, and a $50 per motor fee to get them approved, and Loki said it is cost prohibitive. :(

And friction fitting is always an option, but I have plenty of time before I would try to fly the L1040, so I'll think more about it when I reach that point.
 
I like your idea for the "test flight" :cool: What motor are you planning on using?

Dairy Aire is May 15-17, so I have about two weeks to finish the T2T. I'm not sure yet whether I am going to paint it by Dairy Aire, or make it earn its paint, lol. If you are still planning on maybe going to XPRS, we should drag race. Minimum diameter K2045 drag race perhaps?

Cheers,
Kyle (who is currently patiently waiting for the UPS man)
Yep, a real "test flight" indeed! Not sure on a motor just yet. Some candidates so far are the Loki L1400, L1040, OR a research motor of similar proportions...

I see Dairy Aire is actually the same weekend as our club launch, so we both get to fly that weekend! :) My new plan is to have my rocket fully finished and painted for NXRS, which is June 26-28 this year.
XPRS? Unlikely, but possible... If we cross paths sometime we should definitely dragrace! Any chance of you making it to BALLS this year?

Also, I definitely agree with A5tr0 An0n (and prophecy for that matter) on motor retention - I'm just friction-fitting mine.
 
Yep, a real "test flight" indeed! Not sure on a motor just yet. Some candidates so far are the Loki L1400, L1040, OR a research motor of similar proportions...

I see Dairy Aire is actually the same weekend as our club launch, so we both get to fly that weekend! :) My new plan is to have my rocket fully finished and painted for NXRS, which is June 26-28 this year.
XPRS? Unlikely, but possible... If we cross paths sometime we should definitely dragrace! Any chance of you making it to BALLS this year?

Also, I definitely agree with A5tr0 An0n (and prophecy for that matter) on motor retention - I'm just friction-fitting mine.

I was going to use the Loki L-1040 but the sims put it way over our waiver, 27K so I am using the Loki K-350 instead which sims out at 20K for my Tomach. You guys are spoiled with the monster ceilings you get out West. I have to make it out to Black Rock one day.
 
I was going to use the Loki L-1040 but the sims put it way over our waiver, 27K so I am using the Loki K-350 instead which sims out at 20K for my Tomach. You guys are spoiled with the monster ceilings you get out West. I have to make it out to Black Rock one day.
Hit the nail on the head - we ARE spoiled... I live 4 hours away from our home launch site (Brothers, OR) which houses a 42K waiver, and Black Rock is 9 hours away.
 
My club, LUNAR, is around an hour and a half away and has a 15,000 foot waiver, but they only do launches during the winter from November to April because of the fire danger. Black Rock is about a six hour drive for me.
 
I'm about to start building one of these. As you know, the kit has two main body tubes: a long one and a short one. It seems from the instructions that the long one goes aft. (And that's what TRFers seem to do.)

I'm planning on using motor ejection as backup to the drogue deployment. It seems to me like it would be better to use the short tube in the aft because that would give me more room for the main chute in the forward compartment. Can anyone think of a reason not to do this?

I'm not aiming for maximum performance and won't be flying the longest 54mm motors. (The aft shock cord attachment will be to the tube, using a short, cut coupler assembly I saw on another thread.)

Geof
 
I'm about to start building one of these. As you know, the kit has two main body tubes: a long one and a short one. It seems from the instructions that the long one goes aft. (And that's what TRFers seem to do.)

I'm planning on using motor ejection as backup to the drogue deployment. It seems to me like it would be better to use the short tube in the aft because that would give me more room for the main chute in the forward compartment. Can anyone think of a reason not to do this?

I'm not aiming for maximum performance and won't be flying the longest 54mm motors. (The aft shock cord attachment will be to the tube, using a short, cut coupler assembly I saw on another thread.)

Geof

I am assuming the have the FG 54mm version, if so the payload (upper) tube is only 18". Subtract about 3-3.5" for the altimeter bay coupler plus a min of 3" for some recovery gear, that leaves you with say 12" on the liberal side for a motor. You are really limiting yourself for motors with only 12" to I and some J motors. If that works for you then what you want to do is possible. However the payload tube is sized appropriately for the recovery gear you will need, so swapping the tubes is just effectively going to result in limitations not flexibility.
 
Yes, it's 18". The biggest cases I might want are 54/1280 (12.5in), 38/1080 (18.8in), or 38/720 (13.2in).
However, I can get a nice range of I's and J's with 54/852 (9.1in), 38/600 (11.3in) and 38/480 (9.5in).

If I build it as instructed (with the short tube forward), then I have 18" minus 3 for the ebay minus 3 for the nose cone coupler/bulkplate, which means I need to fit the main chute and harness in about 12" of 54mm tube. At 3.5 lbs, it looks like the chute might be as large as 3.5 ft?? That seems like a lot of fabric and cord to fit in 12".

I'm not arguing, just fretting and pondering....


(PS to OP: what chute(s) are you using?)
 
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