BEHOLD - the coming of THOR!!!

neond7 said:

Just a heads up, that is a defunct website. You can't actually order those kits.

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i understand. i meant our own clone. do you know if there are any templates for the fins out there. we don't have Rocksim, do you think we could convert it into Openrocket and make a template from that?

accpool said:

i understand. i meant our own clone. do you know if there are any templates for the fins out there. we don't have Rocksim, do you think we could convert it into Openrocket and make a template from that?

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You can open Rocksim files in Open Rocket. OR has fin templates.

thanks, will try that tonight. is there a library of OR rocket files i can download?

accpool said:

thanks, will try that tonight. is there a library of OR rocket files i can download?

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Here is the file I used. I modified the original I downloaded, basically I split 34" upper tube and moved the av-bay between those two tubes and put a coupler in the booster section. I also lengthened the motor tube, and as you can see from some of the pics I posted earlier, added a wood thrust ring. Externally it should pretty much look the same as a stock Thor.

View attachment bsd_thor.rkt

neond7 said:

Here is the file I used. I modified the original I downloaded, basically I split 34" upper tube and moved the av-bay between those two tubes and put a coupler in the booster section. I also lengthened the motor tube, and as you can see from some of the pics I posted earlier, added a wood thrust ring. Externally it should pretty much look the same as a stock Thor.

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nice mod, looks good. how do i print fin template in OR?

Here is the Open Rocket file I adapted to match the 4" that I built from a kit (added a 38mm motor adapter).

The kit did not include the fasteners for the AV bay, nor the drogue. I still need to upgrade from the supplied eyebolts to u-bolts.

Don-That lighted THOR is beautiful, I may have to build one a them!

View attachment my thor.ork

accpool said:

nice mod, looks good. how do i print fin template in OR?

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Click on File, choose Print/Export PDF. Deselect everything except Fin Templates, click on Preview/Print. That will bring up a PDF with the fin templates, that you can print, save, etc.

View attachment thor_fins.pdf

The Thor build is moving right along. After tacking in all 3 fins with 30 minute epoxy two nights ago, it sat and fully cured overnight. Last night, using a Dremmel, I removed the small tabs of body tube in back of the fins and slid the fin can out so I could apply decent internal Aeropoxy fillets.

As you can see in the pictures, I also used an internal coupler and two centering rings that help "sandwich" and brace the top and bottom of the fin tabs. To make this, I cut down a coupler to the desired length, slightly reduced the OD of two centering rings to fit snuggly inside the coupler, and epoxied them flush with the edges. Its really important the rings sit flush with the edges of the coupler or things won't fit right.

Last night I applied a bead of Aeropoxy about 1/2" above the top of the lower fin tabs and slid the coupler all the way down, through the epoxy bead until it touched the top of the fin tabs. Then I used a popsicle stick to apply fillets to all the internal joints. Its a very solid structure now.

This morning after it cured all night I test fit the fin can back into the body tube, you can see the top of the coupler through the top fin slot. I'll file the bottom of the fin slot down a hair until it is flush with the top of the coupler. That way, the back fin tab is fully secured when I start tacking in the top fins tonight.

Out of curiosity, I threw it on the scale to get an idea how the weight is coming in, so far the booster section, MMT, and fins are at 2lbs, 11.8oz. Not too bad, and a little lighter than anticipated. They will be getting tip to tip fiberglass later. I don't mind the weight creeping up, as I plan on eventually using a K550W on this and weight will not be an issue.

My "TAGG GPS Pet Tracker" arrived yesterday, so I'll feel MUCH better about sending this to 6,000' or greater. Assuming nice low-wind days, of course. This THOR is going to be built for speed!!!

Never seen someone using Tidy Cat in a rocket build

Scott231 said:

Never seen someone using Tidy Cat in a rocket build

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Lol... Any port in a storm I guess. In some of my smaller builds, the 8-pack Gatorade containers made a handy rocket stand! The trick was to keep my son from stealing them and making my stand lopsided.

Well it was a top secret technique until Jeff let the cat outta the bag.It keeps mice from chewing on your rockets.

Build looks great . . . . following along from the corner of the garage...

qquake2k said:

Click on File, choose Print/Export PDF. Deselect everything except Fin Templates, click on Preview/Print. That will bring up a PDF with the fin templates, that you can print, save, etc.

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that makes too much sense. thanks.

accpool said:

thanks, will try that tonight. is there a library of OR rocket files i can download?

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A WEALTH of rocket design files to be had here: https://www.rocketreviews.com/rocksim-library.html

Just select the manufacturer and then the model. Amazing how thorough the coverage is!

jpummil said:

A WEALTH of rocket design files to be had here: https://www.rocketreviews.com/rocksim-library.html

Just select the manufacturer and then the model. Amazing how thorough the coverage is!

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thanks. is there anything like that for OR? i know i can use RS files, just curious.

accpool said:

thanks. is there anything like that for OR? i know i can use RS files, just curious.

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Not that I'm aware...there are enough custom designers / scratch builders on TRF that we could probably populate one pretty quickly if anyone wanted to host such a site though :grin:

jpummil said:

Not that I'm aware...there are enough custom designers / scratch builders on TRF that we could probably populate one pretty quickly if anyone wanted to host such a site though :grin:

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would it be beneficial? or just an unneeded copy site? would there be a OR file that would be able to have something in the design that RS file wouldn't?

accpool said:

would it be beneficial? or just an unneeded copy site? would there be a OR file that would be able to have something in the design that RS file wouldn't?

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Let's start a new thread so as not to detract any further from the THOR build (sorry Jeff...). Happy to discuss...

me too. started it in software

I like your construction of the fin can. Very sturdy, less room for error than leaving the ring off and applying fillets from the bottom. Have used a coupler piece to lock upper rings in, but not in the middle. Very nice!

T-Rex said:

I like your construction of the fin can. Very sturdy, less room for error than leaving the ring off and applying fillets from the bottom. Have used a coupler piece to lock upper rings in, but not in the middle. Very nice!

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Thank you. Sturdy is the goal for this bird.

Santa Claus showed up while I was at work today and brought me a Rouse Tech 54/2560 motor. Can you say K700W time!!

Front fin is tacking and clamped on place.

This is my first split fin rocket, I won't count the Mad Cow Phoenix I built for my L1 since it was such a crummy build - some day I'll build a new one and do it right. It survived a dozen or so flights before it took its toll on the fillets. If only I had known about epoxy fillers back then!! So much I've learned on this forum.

neond7 said:

Thank you. Sturdy is the goal for this bird.

Santa Claus showed up while I was at work today and brought me a Rouse Tech 54/2560 motor. Can you say K700W time!!

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I'll probably run nekkid across the field when I can finally get mine in the air (probably on an H250G or an I200), it's been completed and hanging in the garage for a little over a year now.

neond7 said:

Thank you. Sturdy is the goal for this bird.

Santa Claus showed up while I was at work today and brought me a Rouse Tech 54/2560 motor. Can you say K700W time!!

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Okay now I am jealous! You REALLY need to come up to Orangeburg for Freedom Launch and fly it!:wink:

Pantherjon said:

Okay now I am jealous! You REALLY need to come up to Orangeburg for Freedom Launch and fly it!:wink:

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Oh, you never know where I will show up. . I'm only a few states South of you....

Anyway, came home and got some work done. All the internal fillets and the centering rings are epoxied in place..

Tomorrow after the Aeropoxy cures, I'll epoxy the fin assembly back into the body tube and start some external fin fillets. If things go good maybe I can start some tip to tip glassing by Sunday. It would be nice to get this cleaned up so I can start parking in the garage again.... *sigh*

Jeff, i am having a hard time understanding the body tube and fin can. is the body tube slotted all the way to the aft end of the rocket? i think it has to be, or you cut the BT open. excuse my noobness.

accpool said:

Jeff, i am having a hard time understanding the body tube and fin can. is the body tube slotted all the way to the aft end of the rocket? i think it has to be, or you cut the BT open. excuse my noobness.

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I did use a Dremel to open the slot all the way between the fore and aft fins after the front fins were tacked in. I used the coupler between the fins to ensure there wouldn't be any weakness there.

After the fin fillets go on, I'll apply tip to tip fiberglass. You'll never know those slots had ever been opened up.

Dual fins are a PIA, though. I'll stick with single fins from now on......

thanks i must have missed that picture in earlier post. could this be done with cardboard tubes? not dremel but knife? i wouldn't want to glass it.

accpool said:

thanks i must have missed that picture in earlier post. could this be done with cardboard tubes? not dremel but knife? i wouldn't want to glass it.

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I'm sure you could do it with a paper tube, I did keep the little body tube tabs that I removed between the upper and lower fin slots and will epoxy them back into place when I mount the assembly back into the body tube. Use Aeropoxy 6209 on your internal fillets and it should all hold together - the material will usually fail before the epoxy does.

The completed assembly weighs 1.9 lbs. Tonight it will get epoxied back into the body tube. I'll use West Systems epoxy thickened with colloidal silica and high density filler for that.

nice, thanks

This morning I completed two major steps.... Rail button installation and epoxying the fin assembly back into the body tube. Both steps went well.

The front rail button was a smidge higher up than I would have liked, but as I has to get the well nut behind it, I installed it forward of the front centering ring.

As always, I used my favorite mixture of West System 105/206 mixed with 404 high density fillet and 406 colloidal silica.