Author Topic: Sig Magnum (Read 13873 times)

Bill Little · « **Reply #50 on:** December 19, 2012, 11:12:13 AM »

Everything is looking good so far, Marcus. Good luck with the build and with the flying!

Bill

MarcusCordeiro · « **Reply #51 on:** December 19, 2012, 12:30:18 PM »

Quote from: Bill Little on December 19, 2012, 11:12:13 AM

Everything is looking good so far, Marcus. Good luck with the build and with the flying!

Bill

Thanks a lot Bill.

Marcus

MarcusCordeiro · « **Reply #52 on:** December 22, 2012, 01:41:55 PM »

Spent all afternoon sanding...
Now, let's sheet everything.

Marcus

Avaiojet · « **Reply #53 on:** December 22, 2012, 02:13:07 PM »

Marcus,

Your third wing photo. Is that a drawn line or material on the edge?

Lookin good so far, you are progressing.

Charles

MarcusCordeiro · « **Reply #54 on:** December 22, 2012, 03:17:31 PM »

The stab is tappered, so I had to draw the lines to guide me sanding.
I liked the result so far, but I want to wait until it's fully finished to pop that champaigne

Marcus

MarcusCordeiro · « **Reply #55 on:** December 23, 2012, 01:47:45 PM »

Got the LE and TE shaped and boy, that TE wood was as hard as a rock!
Now comes the cntrol system thing.
I'd thought about a total overhauling, changing everything, but unfortunately I haven't been able to contact Mr. Tom Morris yet, then,
I think I'll stick to the kit stuff, just replace the pushrods for a Brodak adjustable ball link kit that In have here and that's OK.

Merry Christmas folks!! May the blessing of God be with everybody!!

Marcus

Avaiojet · « **Reply #56 on:** December 23, 2012, 02:27:32 PM »

Marcus,

Can you get a photo of the Brodak hardware?

I'm sure Tom will answer his phone on Monday. Monday is a working day.

Charles

MarcusCordeiro · « **Reply #57 on:** December 31, 2012, 01:02:04 PM »

Sharing time between 2 models is crazy, but vacation is only once a year.
I'll have the stab/elev assembled by tomorrow night.
Got some good 1/32 sheeting, no covering.

Happy new year!!

Marcus

Avaiojet · « **Reply #58 on:** December 31, 2012, 01:09:11 PM »

Quote from: MarcusCordeiro on December 31, 2012, 01:02:04 PM

Sharing time between 2 models is crazy, but vacation is only once a year.I'll have the stab/elev assembled by tomorrow night.
Got some good 1/32 sheeting, no covering.Happy new year!!Marcus

Marcus,

Was 1/32" suggested instead of 1/16"?

I thought everyone was sheeting control surfaces with 1/16" ?

Charles

MarcusCordeiro · « **Reply #59 on:** December 31, 2012, 03:01:03 PM »

No, it was my choice.
The flaps, I think I'll go with 1/16 though.

Marcus

Avaiojet · « **Reply #60 on:** December 31, 2012, 04:23:40 PM »

Quote from: MarcusCordeiro on December 31, 2012, 03:01:03 PM

No, it was my choice.
The flaps, I think I'll go with 1/16 though.Marcus

Marcus,

What did the plans call for?

Ya got plans?

Charles

MarcusCordeiro · « **Reply #61 on:** January 01, 2013, 05:23:10 AM »

Quote from: Avaiojet on December 31, 2012, 04:23:40 PM

Marcus,

What did the plans call for?

Ya got plans?

Charles

The plans ask covering with silkspan or monokote, but they flex too much, specially the flaps, so...

Marcus

MarcusCordeiro · « **Reply #62 on:** January 01, 2013, 04:56:58 PM »

Yep, I did it!

Marcus

RandySmith · « **Reply #63 on:** January 01, 2013, 05:28:33 PM »

Planking helps much with making them stiffer

Randy

Doug Moon · « **Reply #64 on:** January 01, 2013, 07:36:20 PM »

Quote from: MarcusCordeiro on December 22, 2012, 01:41:55 PM

Spent all afternoon sanding...
Now, let's sheet everything.

Marcus

That is really nice work!!!!!!!

MarcusCordeiro · « **Reply #65 on:** January 01, 2013, 11:18:29 PM »

Quote from: RandySmith on January 01, 2013, 05:28:33 PM

Planking helps much with making them stiffer

Randy

Yeah, that was the most common word of advice in previous Magnum topics I could find here in the forum.
But it's quite simple to see, as the flaps will flex and get a propeller shape with essy twisting them with your hands.

Marcus

MarcusCordeiro · « **Reply #66 on:** January 01, 2013, 11:19:23 PM »

Quote from: Doug Moon on January 01, 2013, 07:36:20 PM

That is really nice work!!!!!!!

Thank you Doug.

Marcus

Bill Little · « **Reply #67 on:** January 02, 2013, 11:36:08 AM »

Hi Marcus,

You should have a really good flying model when finished! As everyone has said, sheeting the controls really helps.

Bill

MarcusCordeiro · « **Reply #68 on:** January 02, 2013, 12:20:18 PM »

Quote from: Bill Little on January 02, 2013, 11:36:08 AM

Hi Marcus,

You should have a really good flying model when finished! As everyone has said, sheeting the controls really helps.

Bill

Thanks Bill.

Marcus

MarcusCordeiro · « **Reply #69 on:** January 03, 2013, 10:34:32 AM »

Something very important was to make a poor man's triple core, so no collapsing wings on thhis bird...

Marcus

Bill Little · « **Reply #70 on:** January 03, 2013, 01:24:48 PM »

Great idea, Marcus! It only has to help.

Bill

MarcusCordeiro · « **Reply #71 on:** January 03, 2013, 01:51:43 PM »

You know Bill

I ran a search here to see past Magnum topics and 3 things were everywhere:

-Sheet the flaps

-Make it a triple core

-Reinforce the fuselage at the wing area

Great advice!

Now, let me work on those pushrods...
Wanna have this ship in one piece ASAP.
Need room o0n the bench for my Thundergazer...

Marcus

Bill Little · « **Reply #72 on:** January 03, 2013, 02:41:37 PM »

Hi Marcus,

Many years ago we (Aaron and I) built a Magnum from plans. We had a triple cored wing and used sheet stock for all the control surfaces. It flew really well , but two things happened. One, the finish went South very quickly, and Two, we had just stared using tuned pipes and out Magnum was not set up for a pipe. It has been waiting on a new finish for many years. I hope to get it redone once I get the projects now underway completed. Not sure what engine I will use, I have ST G.51s that run great plus an OS .45FSR and an Evo .60. Either way, I hope to get it finished and finally put a number of flights on it. As it sits, it has maybe 2 dozen flights.

Keep on going with yours!
Bill

MarcusCordeiro · « **Reply #73 on:** January 03, 2013, 04:26:18 PM »

Bill

I hope it doesn"t take us too long to see that ship flying again!!
I'm using brodak's pushrod on this bird.
It's the only mod in the control system actually.

Marcus

Avaiojet · « **Reply #74 on:** January 04, 2013, 11:44:59 AM »

Marcus,

That Brodak pushrod. Does it arrive just as in the photo?

Do you cut it to length and add the ends? Brodak sells the ball links?

4-40?

Charles

MarcusCordeiro · « **Reply #75 on:** January 04, 2013, 12:22:40 PM »

Charles

You have to glue the ends and cut to lenght, but no biggie.
I'm pretty sure it's 4-40.
About the ball links, I think so, gotta check in the site...

About to enter home straight with this bird...

Marcus

Avaiojet · « **Reply #76 on:** January 04, 2013, 02:07:16 PM »

Marcus,

Thanks for that info.

Is that horn a Brodak part also?

Charles

MarcusCordeiro · « **Reply #77 on:** January 04, 2013, 03:50:41 PM »

The horn is the one from the kit.
Got the stab in place...

Marcus

Avaiojet · « **Reply #78 on:** January 04, 2013, 09:07:24 PM »

Marcus,

Looking good, that sheeted stab makes it!

I think I'll do that.

Charles

MarcusCordeiro · « **Reply #79 on:** January 06, 2013, 02:41:48 PM »

With a little effort, I'll have this bird in one piece by the end of the week...

Marcus

Avaiojet · « **Reply #80 on:** January 06, 2013, 06:58:09 PM »

Marcus,

Nice job squaring off the joining of your wing halves.

Epoxy?

Fiberglass cloth for the center section?

Charles

MarcusCordeiro · « **Reply #81 on:** January 06, 2013, 10:17:09 PM »

I used the cradles, had to shim a little, but the wing is straight.
Used slow curing epoxi and yes, I'll reinforce that joint with some fiberglass.

Marcus

Jim Oliver · « **Reply #82 on:** January 07, 2013, 03:33:19 PM »

Marcus,

FYI, I have had two of the threaded links break right where the threads start (or stop, depending on your point of view!). I suspect vibration was the problem, but it happened on two different models.

One of the threaded couplers was steel, one was titanium.
Jim

MarcusCordeiro · « **Reply #83 on:** January 07, 2013, 05:27:58 PM »

Gee, titanium!! I guess that's bad luck...

Marcus

RandySmith · « **Reply #84 on:** January 07, 2013, 07:36:52 PM »

Quote from: MarcusCordeiro on January 06, 2013, 02:41:48 PM

With a little effort, I'll have this bird in one piece by the end of the week...

Marcus

What glue did you use to attach the sheeting?
Randy

MarcusCordeiro · « **Reply #85 on:** January 08, 2013, 03:26:24 AM »

Randy

I'm assuming you're talking about the stab/elev, so for that I used medium viscosity CA, as I will for the flaps.
You cannot compare how much stiffer they are now. I'm seriously considering using 1/16 for the flaps, because they are very flexible, much more than the tail feathers, so a thicker sheeting might be more appropriated.
By the way, what CF landing gear of those you sell would best fit on this ship, if you don't mind me asking? I want to order but not sure of which one.
Let me know and I'll place my order.
I'm having second thoughts about using the wing mounted gear...

Thanks a lot

Marcus

Avaiojet · « **Reply #86 on:** January 08, 2013, 06:07:07 AM »

Marcus,

Joining your wing halves?

Myself and R/C pattern guys always used 6" of fiberglass cloth.

Probably more than needed, but when feathered, you couldn't tell it was there.

Will you use 6" of cloth at your wing center?

Charles

MarcusCordeiro · « **Reply #87 on:** January 08, 2013, 06:12:11 AM »

Quote from: Avaiojet on January 08, 2013, 06:07:07 AM

Marcus,

Joining your wing halves?

Myself and R/C pattern guys always used 6" of fiberglass cloth.

Probably more than needed, but when feathered, you couldn't tell it was there.

Will you use 6" of cloth at your wing center?

Charles

Now I might, I have to go to the store to buy the cloth, but your idea seems good...
The one that came with the kit is only 1"...

Marcus

Avaiojet · « **Reply #88 on:** January 08, 2013, 11:22:09 AM »

Marcus,

Please, I'm not saying that 6" was a "good idea."

It's just the way some of us did it, or at least with pattern ships. I learned from others.

Much of it was sanded and remember, ALL the wings had airfoils that tapered in thickness.

Charles

MarcusCordeiro · « **Reply #89 on:** January 13, 2013, 06:53:04 PM »

Did the weight box.

Marcus

Avaiojet · « **Reply #90 on:** January 14, 2013, 08:51:55 AM »

Marcus,

Looks like most builders use balsa for the weight box lid top.

I can toss my 1/8" ply lid and go with thin ply and then balsa.

Gives me a recessed screw like yours.

Thanks for posting those photos, I just caught it.

Charles

MarcusCordeiro · « **Reply #91 on:** January 14, 2013, 09:09:09 AM »

I used some scrap 1/16 ply to make the box.
Balsa on the lid is much easier to sand.
The wing tip is almost finished, have yet to round it a little...
Gonna work on the leadouts now.

Marcus

MarcusCordeiro · « **Reply #92 on:** January 14, 2013, 12:15:42 PM »

The lead out.
I thought it was better to make a kind of box and glue it to a "half rib", and then glue the assembly to the wing.
I guess it's stronger and I'm sure it's aligned...
Now, to the wing tip block and Dremel on!

Marcus

MarcusCordeiro · « **Reply #93 on:** January 14, 2013, 01:14:54 PM »

I love it when a plan comes together!!

Marcus

MarcusCordeiro · « **Reply #94 on:** January 14, 2013, 06:42:30 PM »

Just a little more and the wing will be done!!

Marcus

MarcusCordeiro · « **Reply #95 on:** January 15, 2013, 01:33:48 PM »

Apart from the fiberglass cloth reinforcement at the certer joint, wing finished...
I wish I had a scale here, it seems light enough.
Anyway, by tomorrow this time, fuselage and wing will be joined as one piece, hopefully

Marcus

Avaiojet · « **Reply #96 on:** January 15, 2013, 02:46:23 PM »

Marcus,

You're the Feature Film!

I go here first. I shouldn't, but I do.

You have your weight box lid on top?

Charles

MarcusCordeiro · « **Reply #97 on:** January 15, 2013, 04:16:11 PM »

Yeah, decided to do it a little unusual

Marcus

MarcusCordeiro · « **Reply #98 on:** January 15, 2013, 06:32:32 PM »

I was thinking about a fuselage mounted LG, but decided to use the one that comes with the kit.

Marcus

MarcusCordeiro · « **Reply #99 on:** January 16, 2013, 10:25:53 AM »

LG OK, joint reinforcement OK, used 2" cloth.
Now let's put the fuselage and the wing together...

Marcus