Loc Lil' Dither

I haven't done much with the Lil Dither I received for Christmas. The hold up is determining the best way to adapt 29mm engines to the 38mm engine tube. I did purchase the Loc 29 to 38 adapter. I can use the adapter kit to fit a 29mm engine in to the 38mm engine tube.

The problem is lack of positive engine retention. For that I will install two 6-32 threaded inserts into the rear CR and use two mirror clips to keep the engine in place.

I have used this method for my friend's Loc Onyx (24 to 29mm), the Loc Starburst I purchased from a fund raiser auction and another kit I resurrected.

The body tubes that come with the kit are sturdy along with 1/8" plywood fins and 1/4" centering rings. The kit includes a quality shock cord, eye bolt and quick release clip. Given that the kit only weighs about 21 ounces, a 38mm motor mount seems too big.

Any ideas or comments?

Well, you don't want to dither about your engine mount so.....
Download the Rocsim file and run some sims:
https://www.rocketreviews.com/locprecision-lil-diter-2190.html
Otherwise you'll be saying

"Ach du Lieber, Zere goes Diter"!

Maybe the name of the kit is causing me to take my time. LOL.
I don't have Rocsim so I rely on historical data that I have documented from previous launches. I am comparing the weight of some of my rockets along with the engines I have used, to the 21 ounce weight of the Lil Dither.

Here in MA our launch sites are not that big. I used to launch with the MMMSC but we can no longer use that field.

Thanks for the reply.

OpenRocket is free and can read Rocsim (.rkt) files.
Invaluable tool for engine choices and rocket design.

not sure what your budget is, but that sounds like a good candidate for an Aeropack set up. their 38mm retainer with 29mm adapter and fly to your hearts content.

that is exactly what i built into the caliber ISP in my avatar and i couldnt be happier.

kuririn said:

OpenRocket is free and can read Rocsim (.rkt) files.

Invaluable tool for engine choices and rocket design.

Click to expand...

I did not know that Open Rocket can read Rocsim .rkt files. I will give it a try.

Thanks for the info.

Theory said:

not sure what your budget is, but that sounds like a good candidate for an Aeropack set up. their 38mm retainer with 29mm adapter and fly to your hearts content.

that is exactly what i built into the caliber ISP in my avatar and i couldnt be happier.

Click to expand...

I use the Aeropack retainers on some of my rockets. Believe it or not, I did consider something similar to your suggestion after watching an Apogee Components video.
https://www.apogeerockets.com/Advanced_Construction_Videos/Rocketry_Video_20
Check out the method at 3:20. Tim uses two engine retainers along with an adapter. That could be heart breaking if you lose a rocket like that.

I am not familiar with the Aeropack 29mm adapter. I looked it up on the Apogee site and Tim has a good video on it. https://www.apogeerockets.com/index.php?main_page=product_motor_info&products_id=665

The 29/38 adapter is around $28 and requires the 38mm retainer which is around $28.
I appreciate the suggestion and the information about the adapter which I was not aware of.

Heh, just for fun I ran some sims on the EMRR RS file.
The AT G67R and G61W 38mm motors give apogees of around 1360'.
Good for a smallish field.
A Loki K1127 gives an apogee of almost 7600'. Max vel. 2042 fps.
That's Mach 1.8 at sea level.
Caliber of stability is .84, so will have to add nose weight.
And of course, the airframe and fins might fail long before reaching max velocity.
Fun to play with though.

Do people that fly Loc mid power kits with 38mm motor tubes usually fly 29mm motors?
If so do you use the adapter/retainer method that Theory mentioned above or do you use a 29mm adapter along with clips to keep the engine from popping out during ejection?

I have a couple of kits that weigh in similar to the Lil Dither at around 20 ounces plus or minus. I usually fly them on single use F's or CTI F reloads. They reach anywhere from 800 ro 1,000 feet.

With the Aeropack set up you can even fly high impulse 24mm motors by nesting the 24mm adapter in the 29. CTI has some solid (and expensive) 24mm motors. Heck, the F63 that goes in the Aerotech 24/60 case would likely work well for small fields.

I just took a look at the documentation that came with the 38mm Aeropack retainer I bought for my Madcow Torrent two years ago. It states that you must have a minimum of .375" (3/8) of the motor tube exposed. I will leave 1/2" exposed (1/8" margin of error) in the event that I want to upgrade to the Aeropack retainer and the 29mm adapter as suggested by Theory.

Happy New Years Everyone! Best wishes for a successful rocket season. My Club has a Winter Follies Launch in a couple of weeks.

I drilled two 3/16 holes 180 degrees apart in the aft CR, centered between the OD and ID. The first threaded insert went in fine. The second insert gave me a hard time but after breaking four of them, I finally got it in. The inserts are made of brass. They have these tabs/notch so that you can get a screw driver to screw the inserts into the hole. Where as the brass is soft, a lot of times one of the tabs will break off. Maybe I should get a tap to make threads into the CR? Does anyone know where I can get steel inserts that take 6-32 screws?

I test fitted a 29mm motor and CTI casing with the Loc 29-38mm adapter and all seems good.

I completed construction of the motor mount and most of the 38/29mm adapter.
This weekend I hope to install the motor mount into the air frame. The kit comes with three CRs. I have a forward CR with an eye bolt. A CR mid way that the forward fin tabs will butt against. I will install the aft CR after the fins are installed. This allows me to use internal fillets.

I have always used flat sticks to place epoxy inside the air frame. when installing the motor mount. I watched a few videos and noticed that some people such as John Coker use dowels. Go to the 18:30 mark.


I was wondering what methodology that others use?

I miss my Loc Lil' Dither .

I have not been able to find out much information about the Lil' Dither kit. I would be interested in what you have to say about it. Given that you miss it, you must like the kit and enjoyed building and flying it.
Did you build yours stock or did you make any modifications?
How did you paint it?
Did you get the decal set?
Did you fly it on 38mm motors or use an adapter to fly 29mm motors.
What motors did you use?
What happened to your kit?
I still miss my 3.0" Saab that I lost many years ago.

This is my first ever Loc kit. I did build an Onyx for a friend a few years ago.
The Lil' Dither now comes with three CRs, an eye bolt for the forward CR and a tubular nylon shock cord. The fins are 1/8 plywood and the CRs are 3/16 or so.
The Loc BTs are very sturdy. The thinner upper BT is very thick. The parts fit very good. You need a bit of masking tape on the transition. Better that than having to sand.

The only real modification I made is to add 10/10 rail buttons and threaded inserts to the rear CR for positive engine retention. I bought the 29-38mm engine adapter. I plan on flying with F engines. I'll determine the exact engine once I do a final weigh in and compare the weight to other rockets/engine combinations I have.

Look forward to hearing about your kit and recommendations.

I built mine stock. In a Hotel Room so I called it the Hotel Express. It was a drag race special but I didn't have it ready for the drag race. This was one of my workhorse rockets and probably the most flown rocket I had. It flew naked for several fights, then I painted the tubes black and fins green. The nose was white, and I left the transition naked. There was no decal set. I flown it on 24 - 38mm motors.

24mm (Using LOC 24/29mm adapter and LOC 29/38mm adapter)
Aerotech F24-4W
CTI G84 Green (Last Flight)

29mm (using LOC 29/38mm adapter)
Aerotech F20-4W
Aerotech F25W
Serotech F27R
CTI F36 SS
Aerotech F37-6W
Aerotech G71R
Aerotech G77R
Aerotech G79W (More than once)
Aerotech G64W (Probably more than once)
KBA G82W
Aerotech H128W (2 times for an altimeter test for another project where the transition was a e-bay)

38mm
Gardei G75 Blue (First Flight)
CTI G46
Aerotech G61W
Aerotech G67R

The last flight I found the hard way that the 24mm CTI's ejection charge was enough to pop its chute and totaled the rocket.

I really miss the rocket and wouldn't mind getting a replacement one of these days

To the amusement of some people in my rocket club, I too tend to get attached to some of my rockets and miss those that get lost or totaled. If possible, I either repair or replace them ASAP. You should get yourself another Lil' Diter.
https://www.discountrocketry.com/precision-diter-p-1805.html

Looks like you flew yours on a wide variety of motors. I'm planning on using a few I see on your list such as the CTI F36 Smokey Sam. They don't call it that for nothing. Do you recall what you set the delay for on the F36? The Aerotech F27 Redline is a good choice. Did you use the 4 or 6 second delay? If I go to NARAM I would try the Aerotech G77.

I going to try and paint it as it looks on the package. I bought the decal set for $25. Wish me luck getting those on properly.

Maybe it's me but I find that some Loc kits come with bigger motor mounts than I would normally fly. For example the Lil Diter has a 38mm where as I would most likely fly on 29mm motors. The Only came with 29mm but my friend flies it on 24mm engines. Perhaps it is because in New England our fields are not as big as other places. I either build or buy the Loc adapters so it's no big deal. If you don't mind spending the money, you can get the Aeropack 38mm retainer and adapter.

yeah, I want to get a new one, but working for a church organization, I don't have much money for rocket kits, and most of the kits I get are from gifts . So maybe I should add it my list for the next secret santa.

If I remember correctly, I chose the shortest delay possible for the f motors. The G's I aimed for 7 seconds. Most of the flights were at CMASS launches. I also firmly believe that 38mm is the size of choice if you are flying G motors. that way you can easily use 24, 29, and 38mm G's

I don't like using retainers. Friction fit has always been reliable for me, and on a rare case of motor failure, all the retainer does is damage your rocket more. Larger than 38mm motors I add some sort of motor anchor.

Fortunately I have never had a CATO in a rocket with an Aeropack retainer. I like them because they look cool. I use them sparingly because of the cost. Some of my kits have the Estes plastic retainers. Can't beat them for the price. I recently bought some nice brass threaded inserts from McMaster-Car. I drill two 17/64 holes in the rear CR and use a 6-32 screw and plastic spacers as engine retention. Very cost effective. I also launch with CMASS. I'm not sure they allow friction fit with larger motor.

I see what you mean concerning the 38mm motor tube. Can you always adapt down but not up. I actually make a 29-24 adapter for my friends Onyx.

Hope to see you at a CMASS launch this year.

I doubt I will be at a cmass launch this year. Last time I been to one was April 2011. I moved to Central PA. Only been to a couple organized launches since the move in 2010. I do plan to fly with SPAAR in May. They have a small launch about an hour from me. So this will be the first organized launch I been to since I got my L3 in 2013. I used to fly with SPAAR in the mid 90's. I did tell my wife maybe some day we make a trip up there and hit a CMASS launch, but money for us is tight so I don't know how soon we could afford to do something like that.

Even though it was seven years ago, congratulations on your level 3. The jump from L2 to L3 is a quantum leap. You can always stay in touch with your CMASS friends in the CMASS forum by going to cmass.org.

deangelo54 said:

Does anyone know where I can get steel inserts that take 6-32 screws?

Click to expand...

I didn't see where anyone answered this.
I use T-Nuts Get them at ACE and they have them for 6-32 screws.
Hint, use a vice to press them in square.

I have done some testing with those T-Nuts that have the pointy tangs that stick in the wood. Best results is if you put a bit of epoxy to hold them in place. That works fine when you are building a new kit and have access to the rear CR. Not to mention very economical.
When the rocket is already assembled, the inserts are a good solution. Lowes sells two inserts per pack for cheap money. Problem is that the tabs break off easily when you are inserting them. Maybe the 8-32 insert are sturdier.

I bought two steel inserts and 25 brass inserts from McMaster-Car. My machinist friend told me to use the steel insert as a tap, remove it, then install the brass insert along with a bit of epoxy on the threads.

I would be interested in hearing about your Level 3 project.

deangelo54 said:

I haven't done much with the Lil Dither I received for Christmas. The hold up is determining the best way to adapt 29mm engines to the 38mm engine tube. I did purchase the Loc 29 to 38 adapter. I can use the adapter kit to fit a 29mm engine in to the 38mm engine tube.

The problem is lack of positive engine retention. For that I will install two 6-32 threaded inserts into the rear CR and use two mirror clips to keep the engine in place.

I have used this method for my friend's Loc Onyx (24 to 29mm), the Loc Starburst I purchased from a fund raiser auction and another kit I resurrected.

The body tubes that come with the kit are sturdy along with 1/8" plywood fins and 1/4" centering rings. The kit includes a quality shock cord, eye bolt and quick release clip. Given that the kit only weighs about 21 ounces, a 38mm motor mount seems too big.

Any ideas or comments?

Click to expand...

I looked at doubling up on motor retainers. First a 38mm on the rocket, then a 29mm retainer on the adapter. I don’t think the 29mm retainer will clear a 38mm retainer mounted on the rocket. I‘ve done dozens of sims (and actual launches) with my Lil Diter. You know what? I don’t think I’ll ever use a 38mm motor in my Diter. Like someone else said, LOC seems to over motor size their rockets. I may just epoxy my 29mm adapter (with 29mm retainer) into my 38mm Lil Diter motor mount and make it permanent. That way I don’t have to friction fit or use masking tape on the rear thrust ring.

deangelo54 said:

I haven't done much with the Lil Dither I received for Christmas. The hold up is determining the best way to adapt 29mm engines to the 38mm engine tube. I did purchase the Loc 29 to 38 adapter. I can use the adapter kit to fit a 29mm engine in to the 38mm engine tube.

The problem is lack of positive engine retention. For that I will install two 6-32 threaded inserts into the rear CR and use two mirror clips to keep the engine in place.

I have used this method for my friend's Loc Onyx (24 to 29mm), the Loc Starburst I purchased from a fund raiser auction and another kit I resurrected.

The body tubes that come with the kit are sturdy along with 1/8" plywood fins and 1/4" centering rings. The kit includes a quality shock cord, eye bolt and quick release clip. Given that the kit only weighs about 21 ounces, a 38mm motor mount seems too big.

Any ideas or comments?

Click to expand...

If you want to make life super easy, get an 38mm aeropack retainer and a 29/38 adaptor. I use this all the time and it is so easy and reliable.

The thing with over sizing the MMT is that you can always adapt down but not up. Given that, I could not imaging launching the Lil Diter on anything larger than a G80.

deangelo54 said:

The thing with over sizing the MMT is that you can always adapt down but not up. Given that, I could not imaging launching the Lil Diter on anything larger than a G80.

Click to expand...

It is a beautiful performer on a H-165R!

deangelo54 said:

The thing with over sizing the MMT is that you can always adapt down but not up. Given that, I could not imaging launching the Lil Diter on anything larger than a G80.

Click to expand...

My flying buddy only sends his up on I435's now! It is a laser off the pad and hard to see at apogee. Probably 6 flights on the I435.

Sandy.

When flying the Lil Diter on HP engines, do you use a chute release?

deangelo54 said:

When flying the Lil Diter on HP engines, do you use a chute release?

Click to expand...

I will answer for my buddy and in his case, no. We have a great field and he only flies it under good wind conditions with the I435. Motor deploy only (drills a few seconds off, I think, but not much. The rocket is built with 5 min epoxy, eventually added some fillets with thickened epoxy. He hardened up the tube edges with thin CA. It flew that way on the I435 a few times. One time, it stripped the chute (possibly not attached correctly. . .) and landed hard on the road and cracked a fin pretty bad. We repaired the fin and did use thin fiberglass to repair that specific fin. I don't believe we did the other fins at the same time, but there is a possibility we did.

I believe the rocket goes 4800-5200-ish feet in the I435 and it is either right above or right below mach. Its really not what someone would recommend as the idea flight regime for a cardboard and plywood rocket most often, but it keeps on kicking!

Sandy.