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Chris McG F-86 Sabre Dog build blog


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Yep those tailplane laminates look lovely - very accurate!

You have some work still to do regarding plan deviations it seems - I've never really studied the form of the Sabre Dog and its not modelled often - it is a very different beast! We look forward to seeing yours take its final form!

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Thanks for these kind words, Phil.

The "beast" is very different indeed...

I might conclude soon that it was a bit pretentious at my level of experience to go for the Dog version of the F-86.

But then, it's way too late now...

I had some small progress, but nothing really worth showing. Apologies for that, gents.

Hakuna matata

Chris

BRU - BE / CTR Brain Bashing#2 Control

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Hello to all,

By the way, Phil. You have been writing the 300th post of my build blog, so I guess I own you a(nother) beer at the Orme… beer

I had a first dry/test fit of the fin & fairing and I must say they look OK so far.

896_fuse_fin_900.jpg

The plan is to have both parts glued together and to sand them both in one go.

Not visible on the pictures, but I’ve also prepared a small carbon rod/dowel inserted to align both parts and to make them stronger while sanding.

898_fuse_fin02_900.jpg

The fin fairing is a lot more ‘sharp edged’ than the F-86 colleague, so I thought there was no point of adding too much doublers at both sides that will be sanded down anyway.

I’m glad I made that U-shaped tunneling in front of the fin as it really helps aligning the parts. smiley

901_fin_fairing_900.jpg

I already have grey hair but I’m getting worried now about losing most of them with this Dog build… frown

Hakuna matata

Chris

BRU - BE / CTR Balt Control

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Hi Dirk,

Your encouragement is indeed very welcome and I really try to make it to The Orme with the Dog.

But unfortunately, my lack of experience is playing me parts and my progression is very slow compared to other MBers, at least those who are ‘posting’ their build… frown

I have a QUESTION please, gents:

My plan is to use a Corona DS 238MG for the elevator. Before installing, I would like to test run it for a while on a servo tester.

With the tester I have (brand > HJ), the Servo Refresh Rate can be set to 50 Hz (20 us), 125 HZ, (8 us) or 250 Hz (4 us).

The 50 Hz rate is used for analog servos, but this one being digital should I use the 125 Hz or 250 Hz selection… ???

I have downloaded several data sheets for the Corona, but none indicates the appropriate rate. sad

Hakuna matata

Chris

BRU - BE / CTR Servo Control

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Apologies, Peter.

I was just typing when you posted.

I have all the drawings, 3 views and 'walkarounds' I could wish for.

Like often, the point is to translate that 2D info into a working 3 dimensional interpretation... cool

Thanks & cheers

Chris

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Hello again,

I prepared the elevator bellcrank ‘stuff’ this session.

907_bellcrank_stuff_900.jpg

From left to right > 2 bits of styrene and 2 nylon washers to be glued inside of both F15 to arrange for the lateral play of the bellcrank.

The drilled bellcrank and the 2 elevator joiners with the brass tube for the front one.

A carbon rod with a 3mm Quicklink at one end to connect to the bellcrank.

… and finally, the ball link for the servo horn.

Regarding the carbon rod, the type that we use mostly in modelling is not a 3K version but a cheaper ‘extruded’ version. That makes the fibers are parallel to each other instead of ‘crossed’ and thus being weaker. To avoid splitting at the ends, a trick is to ‘paint’ some epoxy at the outside and when it’s nearly cured, just slide a portion of heat shrink tube over it and shrink it down. Works perfectly. yes

Speaking of servo, could an Electro Guru please provide some help regarding the Corona question in my previous post? … angel

Hakuna matata

Chris

BRU - BE / CTR Servo #2 Control

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Hello to all,

I had a hairy moment as I thought I made my second ‘big blooper’ already. blush

In fact, I noticed a +/- 1mm play between my fin and both F15 ‘rails’…

How was this possible as formers F9 & F10 were CNC-cut by GM Models with a correct spacing.

Looking at the plan, I noticed (again!) that Martin’s drawing is in Imperial units and I previously converted those to Metric for the fuse build up. But my laminated 2x 6mm made the difference with the 2x ¼ inch obviously… sad

Panic over… and I just glued some bits of 0,4mmm plasticard at both fin bottom sides.

914_fin_lateralplay_900.jpg

I couldn’t resist to have a first dry fit of the fin together with the bellcrank assembly and both elevators.

916_tailplanes_first fit_900.jpg

919_tailplanes_firstfit02_900.jpg

Sorry as the last pic is out of axis as it got me emotionally shaking, but to me it really looks already as the tail end of a Dog… wink

Hakuna matata

Chris

BRU - BE / CTR 2x6mm Control

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Thank you both for your motivating comment, gents.

@ Dirk > the only problem is I don't have a tranny at hand...

I bought a Taranis last year but it was International firmware. A club member proposed to convert it to LBT EU for me.

Since then, it's still with him... blush I can only hope he's still a club member and he didn't move house... surprise

Cheers

Chris

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Hello again,

I made a start with the lateral fin ‘filets’, but with a slight deviation to Martin’s procedure.

The Dog’s ones are wider (again!?) and in an attempt to keep them perfectly parallel to the datum line they aren’t glued to the planking but to the F15s. I just needed to remove a small slice of the planking to insert them.

922_lateralfairings_dryfit_900.jpg

Being wider, I also made the choice to make them hollow to gain a bit of weight. Easy enough by laminating a few soft planks and have some ‘sculpting’…

So far, this shows just a dry fit of the filets-to-be.

929_lateralfairings?dryfit02_900.jpg

The planks of the fuse next to the frontal fairing were also cut and glued in.

Hakuna matata

Chris

BRU - BE / CTR Parallelism Control

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Thanks for your comments, gents.

@ Simon > how is your build progressing?

@ Dirk > thanks for your help proposal. I'll leave the servo adjustments aside for the time being. TBH, I'm not skilled at all regarding the Tx/Rx approach... blush

@ John > let's only hope that it's not going 'to wag' when it's glued in... wink

Cheers

Chris

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Hi again to all,

I need some taper for those lateral filets. Not as much as the F-86, the Dog at 1:10 only having 6mm for the length of the filet.

The idea is to taper a 6mm plank to 1mm and thus needing 1 extra millimetre to be sanded from the outside of the existing filet.

That’s what I did, together with adapting the angle of the elevator root.

932_lateralfairings_dryfit03_900.jpg

Great, but the pic just shows… nothing !!! surprise

Some effect of the wide angle lens, I suppose…

Believe me, the 1mm taper is really there… angel

941_tapered_endplates_900.jpg

I’m afraid this pic isn’t much ‘clearer’.

The first 6mm strip tapered down to 1mm and also bevelled at the bottom where it joins the fuse.

This ends with very fragile bits… and still one to go for… frown

Hakuna matata

Chris

BRU - BE / CTR Taper Control

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Thanks guys,

@ John > well, I guess I need some new specs then... cool frown

Anyhow don't forget your Fantasy GP predictions for Melbourne...

@ Simon > before joining your fuse halves, don't omit to introduce your snakes, battery box and wing bolts plate... surprise wink

Cheers

Chris

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Hi to the gents still following,

All the afore mentioned bits were completed, aligned, checked, cross-checked and finally glued together. angel

I just made sure they wouldn’t ‘leave’ before the glue got cured.

946_tailend_clamped_900.jpg

If you all are very kind and super-friendly, I’ll very probably post a pic when all the clamps will be removed. wink

Hakuna matata

Chris

BRU - BE / CTR Aliphatic Control

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