# Eggfinder Mini 38mm Nose Cone and Shock Cord Mounts

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#### Cl(VII)

##### Chris Bender, Lab Rat

Some of you may have been following along with my development of a NC and shockcord mounting solution for the Eggfinder mini. Well, I finally got it where it needs to be to offer a limited run of these for sale. I want to emphasize that this is a limited run. I'm not trying to end run the vendor rules as I am really still up in the air on the idea, but I'm doing a "vendor beta test" that I have discussed with one of the mods beforehand. I also do not plan to directly compete in any existing niches like those occupied by Additive Aerospace.

A full description of development and use can be found here: https://www.rocketryforum.com/showthread.php?140774-EggFinder-Mini-3D-Printed-Sled-38mm-NC-and-Shockcord-Mounts-Available-for-Order

1) The Shockcord Mount: Contains - (1) Sled, (1) Outer Shell and (5) 4-40 screws - Price $21 2) Nose Cone Mount: Contains - (1) Sled, (1) Bulkhead, (1) Drill Alignment Guide and (5) M4 set screws - Price$20

Fits Wildman/CTI Injected molded cones and Madcow/RW filament wound NCs.

3) The Works: Includes - (1) Sled, (1) Outer Shell, (1) Bulkhead, (1) Drill Guide, (5) 4-40 screws and (5) M4 Set Screws - Price $30 4) Just The Sled - Price:$15

Sled fits in a 29mm body tube (not coupler tube).

If you would like something PM me what you would like (include your PayPal email address), and I will invoice you via PayPal when your item is ready to go. That way you have all the PayPal protection, and I'm not taking money for something I don't have in hand...we've seen that go wrong around here before.

Shipping will be standard USPS for $4 CONUS on up to 4 units. I expect that invoices will go out over the holiday weekend and shipment will begin on the 5th, but again I will not invoice until your order is ready to go. Last edited: #### patelldp ##### Well-Known Member That looks wonderful! #### Cl(VII) ##### Chris Bender, Lab Rat TRF Sponsor Thanks to those who have already PMed orders. You should have received a PM in reply by now, if not please send another message so I don;t miss you. The printer is chugging away, so I should be able to start sending invoices in the next couple days. Still time to get in, but we are getting close to accounting for my current spool of orange filament. At that time there will be a bit of delay while I get more in. No one local carries my preferred brand. That looks wonderful! Thanks. #### Onebadhawk ##### Sponsor TRF Sponsor Some of you may have been following along with my development of a NC and shockcord mounting solution for the Eggfinder mini. Well, I finally got it where it needs to be to offer a limited run of these for sale. I want to emphasize that this is a limited run. I'm not trying to end run the vendor rules as I am really still up in the air on the idea, but I'm doing a "vendor beta test" that I have discussed with one of the mods beforehand. I also do not plan to directly compete in any existing niches like those occupied by Additive Aerospace. A full description of development and use can be found here: https://www.rocketryforum.com/showthread.php?140774-EggFinder-Mini-3D-Printed-Sled-38mm-NC-and-Shockcord-Mounts-Available-for-Order 1) The Shockcord Mount: Contains - (1) Sled, (1) Outer Shell and (5) 4-40 screws - Price$21

2) Nose Cone Mount: Contains - (1) Sled, (1) Bulkhead, (1) Drill Alignment Guide and (5) M4 set screws - Price $20 Fits Wildman/CTI Injected molded cones and Madcow/RW filament wound NCs. 3) The Works: Includes - (1) Sled, (1) Outer Shell, (1) Bulkhead, (1) Drill Guide, (5) 4-40 screws and (5) M4 Set Screws - Price$30

4) Just The Sled - Price: $15 Sled fits in a 29mm body tube (not coupler tube). If you would like something PM me what you would like (include your PayPal email address), and I will invoice you via PayPal when your item is ready to go. That way you have all the PayPal protection, and I'm not taking money for something I don't have in hand...we've seen that go wrong around here before. Shipping will be standard USPS for$4 CONUS on up to 4 units.

I expect that invoices will go out over the holiday weekend and shipment will begin on the 5th, but again I will not invoice until your order is ready to go.

the idea is completely original,,
and I applaud your professional integrity to not make something that already exists...
I am not fully understanding how these parts assemble,
Maybe make this a bit more explanatory..
Does one tube have a straight wall because it's a coupler
and the other fit's up into a nosecone ??

You're going to do really well with this..
MANY people build high performance small rockets..
The limiting factor has always been tracking it...

A big congrats for you..

Teddy

#### Cl(VII)

##### Chris Bender, Lab Rat
the idea is completely original,,
and I applaud your professional integrity to not make something that already exists...
I am not fully understanding how these parts assemble,
Maybe make this a bit more explanatory..
Does one tube have a straight wall because it's a coupler
and the other fit's up into a nosecone ??

You're going to do really well with this..
MANY people build high performance small rockets..
The limiting factor has always been tracking it...

A big congrats for you..

Teddy
Thanks Teddy. Getting away from all thread is the big thing with these trackers, and I wanted an off-the-shelf solution for that. I have been making similar systems out of plywood, G10 and blue tube for several years, but they are total kludges compared to what 3D printing has allowed me to design and make.

As for competing in existing space. I really like the additive Aerospace sleds, and use them myself. I also have their external Mobius shroud. Between those products and the LiquidFyre Mobius system those spaces are well served by good products. It is in trackers and nosecone mounts that I see the void. That is where I will be putting effort as I need those parts too. I won't say you'll never see an altimeter mount from me, but it will be designed around nosecone mounting (or maybe an all-thread-free altimeter bay solution), i.e. an unserved/under served niche.

No reason not to put the entire explanation for how these work in this thread, so I will copy over the more detailed posts about each option.

Short story about the "Outer Shell" (straight tube-like) part. It is intended to slip over the sled to protect the electronics and battery if attached to the shock cord with no other protection. It does not have to be used in Nose cone mounting, and won't fit inside most 38mm NCs when installed. It would provide extra strength and protection for the seld if it were in place when mounted in a larger nosecone (most 54 mm would be fine), or electronics bay.

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#### Cl(VII)

1) The Shockcord Mount: Contains - (1) Sled, (1) Outer Shell and (5) 4-40 screws - Price 21 What you need to add: (1) Eyebolt and Nut, (3) Zip Ties, Eggfinder Mini, LiPo, (2) Mounting Screws for EF-minir (I like 4-40 nylon shearpins). Mounting is pretty self explanatory, but be sure to pull zipties tight and pay attention to the location of the ziptie's "head"...keep them away from edge of LiPo as it will interfere with Outer Shell alignment. Slide sled into case making sure rear hole in Sled aligns with that on the Outer Shell...there are guides printed into the outer shell to ensure alignment as long as you start out within about 15 degrees of aligned. Once the sled bottom is level with the case the holes should be aligned and the screws can be inserted...the top screw alone provided strength to 72 lbs of force at which time the sled snapped. With all three in place the scale was maxed at 110 lbs with no sign of damage. Also, the sled will fit inside a 29mm body tube (Estes PSII Motor Mount pictured). #### Cl(VII) ##### Chris Bender, Lab Rat TRF Sponsor 2) Nose Cone Mount: Contains - (1) Sled, (1) Bulkhead, (1) Drill Alignment Guide and (5) M4 set screws - Price20

What you need to add: (1) Eyebolt and Nut, (3) Zip Ties, Eggfinder Mini, LiPo, (2) Mounting Screws for EF-mini (I like 4-40 nylon shearpins), 38 Nose Cone (Wildman/CTI Injected molded or Madcow/RW Filament wound, and NC bulkhead (if available and desired)...could substitute a fender washer or wooden bulkhead (could go without, but I wouldn't recommend it).

Mounting is pretty self explanatory, but be sure to pull zipties tight and pay attention to the location of the ziptie's "head"...keep them away from edge of LiPo as it will interfere with Outer Shell alignment. Use the Eyebolt to make a bulkhead sandwich as shown.

Next you need to prep the nosecone. Specifically the holes must align with those already printed into the bulkhead. To accomplish this use the included drill guide. Place the drill guide THIN SIDE AFT on the NC shoulder/coupler, and drill one hole with a 1/8 drill bit. Ideally remove the guide and tap the hole for an M4 screw. Realign the guide to the hole and insert an M4 set screw to ensure proper alignment is maintained, and repeat process for remaining holes. This isn't as hard as it may sound...as long as the aft end of the guide and the aft end of the NC shoulder/coupler stay flush and square (helps to stand the NC/coupler on the table top for this), and the first hole doesn't lose it's relationship to the guide everything will come out fine.

Lastly, slide the bulkhead in and screw in the set screws making sure they are properly recessed into the coupler. For the Madcow/RW cones one wrap of masking tape around the coupler will ensure a snug fit)

#### Cl(VII)

##### Chris Bender, Lab Rat
3) The Works: Includes - (1) Sled, (1) Outer Shell, (1) Bulkhead, (1) Drill Guide, (5) 4-40 screws and (5) M4 Set Screws - Price $30 Directions same as with above options. You could also use the Outer Shell with the full bulkhead stack of The Nose cone mount system for shock cord attachment too, but the nose cone mount setup will not fit indie the 38mm nose cones with the Outer Shell in place. 4) If you only want the sled you can buy that for$15.

#### Cl(VII)

##### Chris Bender, Lab Rat
Well, these have been rather popular. With a new spool of filament having arrived I am good to print a few more past the current queue (which should be caught up by Wednesday Morning), but I will run out of set screws and 4-40 screws after a few more have been ordered, so I'm approaching my near term limit.

These would be perfect for the nose cone of a 38mm Go Devil that Madcow has on sale this weekend.

#### Cl(VII)

##### Chris Bender, Lab Rat
Thanks for the response folks. I'm almost caught up to the orders...printer has been going non-stop for 5 days now. In all those cycles there has been one minor update to the design. It occurred to me that under sizing the bulkhead for the RW cone to accommodate the Wildman/CTI cone was kind of unnecessary. PETG is an easily sanded product, so the bulkhead got updated to be 0.1 mm oversized for the RW cone. As an experiment I sanded one to fit the RW cone in 1 min using 120 grit, and it fit the Wildman/CTI cone after 1 minute more sanding. As we are all accustomed to sanding I doubt many will object to 1-2 minutes of sanding to get a nice tight seal on the NC bulkhead, as opposed to being left with a masking tape shim.

Anyhow, I will take orders for a few more days, but then I will need to do some printer preventative maintenance...I have never run it this long before, and I want to give it a going over.

I look forward to hearing the experiences of the early adopters, and if you have any issues please contact me as I want you to be happy, and the product to always be improving.

#### Cl(VII)

##### Chris Bender, Lab Rat
All the orders are filled (all but two shipped), and my printer is at rest.

Because I print in multiples I have two remaining "The Works" sets left if anyone is still interested.

Thanks again for the great response.

#### Banzai88

##### Lvl 1,Wallet....Destroyed
TRF Supporter
Got mine. THANK YOU! Awesome work. I'm very happy. Will be fitting everything up this weekend.

#### Cl(VII)

##### Chris Bender, Lab Rat
Got mine. THANK YOU! Awesome work. I'm very happy. Will be fitting everything up this weekend.
It sounds cliche, but if you are happy, then I am happy.

#### Cl(VII)

##### Chris Bender, Lab Rat
I was asked yesterday, so I'll say these (and the full sized EF version) are still available in any option.

Also, I'll bring some along to Airfest if you want to check one out in person.

#### Nick@JET

##### Well-Known Member
I was asked yesterday, so I'll say these (and the full sized EF version) are still available in any option.

Also, I'll bring some along to Airfest if you want to check one out in person.
I do! Really thinking about these - but don't have egg finder. I would
Like to see , touch etc. This may spur me on.

#### Cl(VII)

##### Chris Bender, Lab Rat
One last bump. I will be at Airfest from Fri-Sun (maybe Mon too), and I will have these kits and those that accommodate the full sized Eggfinders with me. I (Chris Bender) will likely be setup somewhere near a Texas flag, so come by and check these out or just talk rockets...I want to put some faces to names and aliases this year.

My only request is if you see me working on a big V2 (probably Sat morning) check back later as that will be for my L3 attempt.

#### Eric

##### Well-Known Member
If anyone is debating picking one of these up. I would highly recommend it. This is an amazing sled. Also the Eggfinder mini is super amazing. Thanks to Chris and Cris for your amazing products.

Now I need to order just the cover for shock cord mounting.

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#### rcguy5

##### Active Member
Sent you a pm and just noticed they are on eBay. Just curious as to where you got the eyebolt in the pictures?

Mike

#### Eric

##### Well-Known Member
My eye bold is just a stainless 1/4" from home depot. Not welded. I am looking for some welded SS eye bolts,

Sent from my VS988 using Tapatalk

#### Cl(VII)

##### Chris Bender, Lab Rat
Sorry about not getting back to messages. I will catch up upon getting home from Airfest. I track all of the rders and inquiries on mu computer, and I only brought my phone.

Also, I spanked the NC unit in a Go Devil 38 on a Loki K627 today. EF mini took me right to the landing. Highest data received was near apogee above 16k.

#### Cl(VII)

##### Chris Bender, Lab Rat
E-rigging.com is where I buy my eyebolts. Very good products and good pricing. Teddy also sells some quality stuff too.

I recommend welded eyebolts, as at least one beta tester had the bolt open.

#### Cl(VII)

##### Chris Bender, Lab Rat
I think I caught up to all of the back PMs. If you were expecting one from me, and didn't get it contact me again...and sorry.

If you need sleds for those Eggfinder dohickies you bought from Cris' sale let me know. The mini nose cone mounted sled carried my EF-mini to over 16k this last weekend in a 38 MD on a Loki K627, so you can hit these pretty hard. I know of at least one person who flew the shock cord mount version successfully too.

#### Tonimus

##### Well-Known Member
Free bump from a satisfied customer. The fit of these is phenomenal. The way the sled slides into the case is brilliant. There are locating tabs inside the case that keep the sled pressed up against the side of the case so that the retaining screw can keep it from moving around. A fantastic way to minimize movement and minimize the amount of hardware at the same time.

One important extra for a guy like me; there are two extra grub screws and truss head screws. I have a severe case of the dropsies and this is a nice added touch.

To echo other sentiments, if you are on the fence, you better get one before Chris decides that he's had enough of dealing with us!

#### Cl(VII)

##### Chris Bender, Lab Rat
Thanks very much for the endorsement. The extra screws are there because my personal experience has taught me not to consider them "extras", but to consider them "inevitables".

As for "dealing" with you all, it has been my pleasure. There are quite a few of these sleds out there, and I get a kick out of knowing my stuff is proving useful in far more flights than just my own.

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#### 0011001100

##### A Person
Would this fit into a performance hobbies 38mm fiberglass nosecone?

#### Cl(VII)

##### Chris Bender, Lab Rat
Would this fit into a performance hobbies 38mm fiberglass nosecone?
Short answer I don't know. If you can take measurements of the shoulder opening and the total depth from shoulder opening to tip I can tell you for sure. I would be pretty surprised if it is not for the ogive and VK profiles, but the conicals may narrow too quickly. It fits the CTI/Wildman cone, and that one is significantly tighter than the Madcow/RW version.

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#### Eric

##### Well-Known Member
Thanks very much for the endorsement. The extra screws are there because my personal experience has taught me not to consider them "extras", but to consider them "inevitables".

As for "dealing" with you all, it has been my pleasure. There are quite a few of these sleds out there, and I get a kick out of knowing my stuff is proving useful in far more flights than just my own.
Mounted for use in different nose comes. Now its in "Nuffun" a 2.6" CF/FG rocket going for L2 attempt this Saturday.

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