Mercury Atlas

[rocketguy101]

Here is a dry fit of both nacelles over the fin tube. I have some sanding and filling to do!

I am still thinking about the bayonet mount. I originally had a "180 degree" half turn, but now think a 90 degree quarter turn will better, so the fins won't interfere with each other. The attached drawing has more bits and pieces I am using in this model.

I have modeled this in RockSim using pods to simulate the fin tubes. It shows to be stable with the fins in the RS model, but I will have to refine it a bit as the weights and CG get more defined.

Edit: be sure to get the new page in post 83 that has some additional details





View attachment MercAtlas_Scl45.PDF

View attachment MercuryAtlas_45.rkt

 

[cruzsergio]

this is awesome ! op: :clap:

 

[thobin]

this is awesome ! op: :clap:

Yes it is!


TA

 

[rocketguy101]

Just a head's up...when you cut the ribs for the nacelles, double-, triple-check the fit-up. I got in a hurry, and at first glance (pics above) they looked "close enough". Now that I have glued them down, I see I left a little extra stock on the ribs (cut from mat board), so the upper nacelle skin does not pull down nice and tight.

I can work around it, but now I have a lot of filling and sanding to do So, more work up-front will save some time later.

I coated the nacelles and upper shroud w/ CA (do it in a well ventilated area!!) so now they are like plastic and can be sanded very smooth.

 

[rocketguy101]

Equipment side pods are finished, and glued to the booster

 

[cruzsergio]

Equipment side pods are finished, and glued to the booster

IT looks Great !

 

[qquake2k]

Awesome job on the pods!

 

[cruzsergio]

Equipment side pods are finished, and glued to the booster

I sort of got lazy on mine, i made mines from tubes ans i yet have to make the nosecones for it.
I'm not good with adding detail

 

[rocketguy101]

thanks for the compliments....

but HOLY COW! check out this 1/48th model!! https://www.spacemodels.dk/Atlas/Atlas.html

 

[K'Tesh]

Now I remember why I bought two of those Estes Kits...

Nice Job on your scratch build!

 

[rocketguy101]

Made some more progress on the "naughty bits"...

I carved the vernier rocket housings out of some 3/8" balsa, then made a triangular cap that was wider than the block, and rounded the edges to get that look of the housing where it flares out. On the real Atlas, that is sheet metal, but I left everything solid. I used a piece of 1/8" dowel and formed a wedge groove on a lathe to simulate the nozzle...it sorta works--close enough for government work.

The Spacecraft/Booster Umbilical Interface was a fun job...the tunnel is balsa strip, that enlarged portion is a piece of 3/8" dowel machined on the lathe then sanded down to a half round piece. A table top belt sander with 220 grit is really helpful here.

In the daylight photos you can see my cruddy fill job on those nacelles, I still have some work to do on them!!!

I am dreading the tower!!! I found a 1/4" launch lug from Balsa Machining is nearly the perfect OD to make the LES motor, so I am making some caps from dowel to glue on each end. I have ordered some 1/16" dowel that I will draw down to .04 to make the LES truss work. I am not bothering to make the cross braces from smaller diameter dowel, it will all be one diameter. I may not mess with the spike on top, I know the plastic one on my Centuri Mercury Redstone lasted one flight (IIRC, it was supposed to be removable but I forgot and glued it on )

Rather than try to turn the LES motor nozzles from dowel, I am opting to make the nozzles from paper and glue to short 1/8 dowel ... turns out the mini shroud dimensions are: R1= .345 R2= .691 and the angle theta = 62.6 degrees.

 

[rocketguy101]

...and so it begins

 

[cruzsergio]

Made some more progress on the "naughty bits"...

I carved the vernier rocket housings out of some 3/8" balsa, then made a triangular cap that was wider than the block, and rounded the edges to get that look of the housing where it flares out. On the real Atlas, that is sheet metal, but I left everything solid. I used a piece of 1/8" dowel and formed a wedge groove on a lathe to simulate the nozzle...it sorta works--close enough for government work.

The Spacecraft/Booster Umbilical Interface was a fun job...the tunnel is balsa strip, that enlarged portion is a piece of 3/8" dowel machined on the lathe then sanded down to a half round piece. A table top belt sander with 220 grit is really helpful here.

In the daylight photos you can see my cruddy fill job on those nacelles, I still have some work to do on them!!!

I am dreading the tower!!! I found a 1/4" launch lug from Balsa Machining is nearly the perfect OD to make the LES motor, so I am making some caps from dowel to glue on each end. I have ordered some 1/16" dowel that I will draw down to .04 to make the LES truss work. I am not bothering to make the cross braces from smaller diameter dowel, it will all be one diameter. I may not mess with the spike on top, I know the plastic one on my Centuri Mercury Redstone lasted one flight (IIRC, it was supposed to be removable but I forgot and glued it on )

Rather than try to turn the LES motor nozzles from dowel, I am opting to make the nozzles from paper and glue to short 1/8 dowel ... turns out the mini shroud dimensions are: R1= .345 R2= .691 and the angle theta = 62.6 degrees.

WOW just WOW

 

[hornet driver]

YEP !! Way impressed!! Very Nice !

 

[aerostadt]

The detail looks great!

 

[qquake2k]

...and so it begins

That brings back memories of the Estes Mercury Redstone I built as a kid.

 

[rocketguy101]

That brings back memories of the Estes Mercury Redstone I built as a kid.

Oh! thanks for that! I forgot about the old MR...I have been trying to figure how to handle some of the tower assembly. I d/l the instructions from JimZ and see some techniques that will apply here! Although I have already built a complete "ladder" (two vertical rods and the "Z" truss in between). All of the Apollo towers are four-sided, this triangle thing has me scratching my head... wish I had seen the k-41 instructions first!

 

[qquake2k]

Oh! thanks for that! I forgot about the old MR...I have been trying to figure how to handle some of the tower assembly. I d/l the instructions from JimZ and see some techniques that will apply here! Although I have already built a complete "ladder" (two vertical rods and the "Z" truss in between). All of the Apollo towers are four-sided, this triangle thing has me scratching my head... wish I had seen the k-41 instructions first!

I remember the Mercury Redstone kit didn't come with dowels. There were pieces of what looked like bead molding, that you had to split with an Xacto.

 

[MartinVrstal]

What an outstanding rocketguy scratch build. Can't wait to see it all finished up.

 

[rocketguy101]

What an outstanding rocketguy scratch build. Can't wait to see it all finished up.

*blush* thanks

Making some progress...like I said earlier I wish I had looked at the old Estes MR K-41 instructions (thanks qquake2k!!) before gluing my LES tower "ladder"...I think doing it the Estes way would have been a little easier...

As it is, I have one ladder, then another side w/ a single vertical leg and the "Z" lattice, then loose pieces. I made a simple jig to hold the legs in place and glued two sides of the tower together tonight. When it dries, I will add the individual lattice pieces to complete the trianglar frame. I have the "V" pieces ready that will glue to the capsule.

The LES motor is ready to glue on top of the tower. I will add the nozzles later (I already had this planned out before seeing the K-41 instructions ) Funny, I had already planned to use a simplied jettison motor rather than trying to create tiny nozzles...I see Estes did the same...great minds think alike!

If you make the LES nozzles like Estes, in step 29, you can just taper that dowel with a pencil sharpener so the dowel will fit into the nozzle. The dowel doesn't need to be sharp, just tapered enough to fit down the cone.

The extra cross member Estes mentions in step 25 was driving me nuts...my CAD model doesn't have it, and I double checked the David Week's drawing, no lower cross brace. Finally I found this picture on the Apollo Image Archive and it confirms no extra brace. In fact looking back into the Redstone pictures seem to show no extra cross brace.

I made the capsule aerodynamic wedge from a mat board ring. After gluing to the capsule, I coated the OD with CA, then when it dried, I sanded the bevel shape (seeing the close up pic shows I need some more sanding). I apologize for not labeling the alignment in the drawing, so I am including a pic with the revised labels.

 

[cruzsergio]

*blush* thanks

Making some progress...like I said earlier I wish I had looked at the old Estes MR K-41 instructions (thanks qquake2k!!) before gluing my LES tower "ladder"...I think doing it the Estes way would have been a little easier...

As it is, I have one ladder, then another side w/ a single vertical leg and the "Z" lattice, then loose pieces. I made a simple jig to hold the legs in place and glued two sides of the tower together tonight. When it dries, I will add the individual lattice pieces to complete the trianglar frame. I have the "V" pieces ready that will glue to the capsule.

The LES motor is ready to glue on top of the tower. I will add the nozzles later (I already had this planned out before seeing the K-41 instructions ) Funny, I had already planned to use a simplied jettison motor rather than trying to create tiny nozzles...I see Estes did the same...great minds think alike!

If you make the LES nozzles like Estes, in step 29, you can just taper that dowel with a pencil sharpener so the dowel will fit into the nozzle. The dowel doesn't need to be sharp, just tapered enough to fit down the cone.

The extra cross member Estes mentions in step 25 was driving me nuts...my CAD model doesn't have it, and I double checked the David Week's drawing, no lower cross brace. Finally I found this picture on the Apollo Image Archive and it confirms no extra brace. In fact looking back into the Redstone pictures seem to show no extra cross brace.

I made the capsule aerodynamic wedge from a mat board ring. After gluing to the capsule, I coated the OD with CA, then when it dried, I sanded the bevel shape (seeing the close up pic shows I need some more sanding). I apologize for not labeling the alignment in the drawing, so I am including a pic with the revised labels.

op:this is great !
:clap:
It looks awesome !

 

[rocketguy101]

Making some more progress, I added the LOX Tank Pressurization Line and the Fuel Tank Pressure Line (the skinny lines running from the Vernier Motors).

The LES Tower lattice structure is complete and as I was dry fitting the tower to the LES Motor, I realized I had mis-interpreted the David Weeks drawing :y: I see now there is a flange at the base of the motor that the tower attaches to. I made a ring from mat board and glued it to the motor, then soaked the edge w/ CA to strengthen it.

I will post revised pages to the pdf files I posted earlier.

 

[rocketguy101]

Here are the revised pages with new details and proper labeling. I made a template to cut some corrugated styrene for the booster interstage ribbed structure. The scale corrugations are about 0.04 wide, and I have some Plastruct "HO Scale/1:100 Corrugated Siding" # 91509 (from Tower Hobbies) that is pretty close. I hand-fitted a cardstock template to the model, then measured it.

View attachment MercAtlas_Scl45_Page 6.pdf

View attachment MercuryAtlas_Scale_Page 1_REV A.pdf

View attachment MercuryAtlas_Scale_Page 6_REV A.pdf

 

[rocketguy101]

Believe it or not, the part I have dreaded the most to build was the LOX Tank Fill and Drain Pipe. Mainly I have trying to figure out how to create the "ell"...I don't have access to the nifty Plastruct plastic piping parts, and shipping for mail order would have been too expensive.

I finally decided to carve one out of balsa (some of the scrap left over from the vernier motor housings). That actually turned out a little easier than anticipated. Next trying to figure out the round expansion at the other end. Again, I turned to balsa, making a donut that I slipped over the 1/4" dowel, and then sanded to shape...it isn't perfect, but from 5 feet away, looks OK . My mistake was gluing and sanding that piece after gluing the ell and the 1/8" dowel in place (third photo below). If I had put it on first, I could have chucked the dowel in my lathe and sanded away

After I started sanding on "the blob" I realized it could be made by drilling a 3/8" wooden bead out to fit the 1/4" dowel.

You will note I simplified that lower manifolding...rather than trying to blend two 1/8" dowels and making all the bends, I just went with a straight piece and two straight pieces. Probably bad for cryogenic fluid dynamics, but good for my patience!!

After gluing this on, I will need to construct yet another ell for the fuel drain...not only is it an ell, it tapers!!!!:y:

I am not going to attempt the engine turbine duct...I will end up in a rubber room mumbling to myself.

I am about ready to start primer and paint.

 

[rocketguy101]

The last of the details are glued on, now I need to add the launch lugs, then I can start primering and painting

I have not glued the tower on, since it will be easier to paint the capsule and tower separately, then glue it on...it has been killing me because I want to see the whole thing together! Now if the weather will cooperate...

Edit: oh yeah, I put the LES nozzles on the tower, so it is complete (well except for the obvious...)

 

[qquake2k]

Such attention to detail! Amazing!

 

[modeltrains]

Lots of fun to follow. Styrene worked well.

 

[sodmeister]

My hats off to you David ! A very fine build and great craftsmanship all around ,love the details you are adding.

Your tower turned out very nicely ,I can truly appreciate that.

Love watching your build :handshake:

Sincerely;

Paul T

 

[thobin]

Believe it or not, the part I have dreaded the most to build was the LOX Tank Fill and Drain Pipe. Mainly I have trying to figure out how to create the "ell"...I don't have access to the nifty Plastruct plastic piping parts, and shipping for mail order would have been too expensive.

I finally decided to carve one out of balsa (some of the scrap left over from the vernier motor housings). That actually turned out a little easier than anticipated. Next trying to figure out the round expansion at the other end. Again, I turned to balsa, making a donut that I slipped over the 1/4" dowel, and then sanded to shape...it isn't perfect, but from 5 feet away, looks OK . My mistake was gluing and sanding that piece after gluing the ell and the 1/8" dowel in place (third photo below). If I had put it on first, I could have chucked the dowel in my lathe and sanded away

After I started sanding on "the blob" I realized it could be made by drilling a 3/8" wooden bead out to fit the 1/4" dowel.

You will note I simplified that lower manifolding...rather than trying to blend two 1/8" dowels and making all the bends, I just went with a straight piece and two straight pieces. Probably bad for cryogenic fluid dynamics, but good for my patience!!

After gluing this on, I will need to construct yet another ell for the fuel drain...not only is it an ell, it tapers!!!!:y:

I am not going to attempt the engine turbine duct...I will end up in a rubber room mumbling to myself.

I am about ready to start primer and paint.

Knocked it out of the park it looks great. op:

TA

 

[rocketguy101]

Thanks for the compliments everybody...I feel like a rank amateur compared to many of the other builds I see here...:blush:

It is too windy here today to launch, our club had to scrub, so I decided to hit this thing with some primer this morning...I've been like a kid on Christmas...it is finally dry enough to touch (but not sand)...I don't have as much rework to do as I thought...

I put a coat of white on the LES tower and struts because I tested red on the gray primer, and it didn't pop like I wanted (using same red as I put on my Big Daddy, so it should be pretty bright).

I am rethinking my fins...added through the wall tabs and slotted the tubes so I can glue the plastic tabs together hoping for a better bond of plastic-to-plastic. Also rather than the twist-lock mess, I just added a short 1/8" dowel that will fit into a hole on the bottom of the booster to prevent rotation, and use tape to friction fit the fin tubes in place.

Edit: and yes, I got in a hurry to primer the fin tubes and forgot the dowels!!!