1/6.78 Scale Hawker Typhoon

Michael · March 17, 2013, 03:44:32 PM

Nice photos.

That Typhoon is a big plane.

wollins · March 17, 2013, 11:06:59 PM

Yup! They sometimes called her "The Beast"! The pic says why.

Colin

wollins · March 26, 2013, 09:20:22 PM

Well I can't believe it but she's pretty much all wired up now! Got the power system wired up tonight (ESC, UBEC and shunt switch) so theroretically I can fire her up as we speak.

As I mentioned before I was able to go with the original hatch that I'd cut so long ago since I'm gonna go with smaller batteries. (10S 5800mah @ 56ozs as opposed to 10S 8000mah @75ozs!) Always scary to cut a hatch into a composit plane ... never mind twice! Let hope I never have a high speed nose in cause there're some serious "bits" at the business end of this beast.

Colin

piker · March 27, 2013, 11:08:01 AM

Test flight this weekend?

How did the tail wheel work out? Photos?

wollins · March 27, 2013, 11:37:47 AM

We're awaaaaaays from a test flight. I have to be flying everything else before I'll trust my thumbs to this maiden.

I just want to get it done to flying stage so I can leave it off and get on with the damn queue! Tailwheel is coming ... still needs LOTS of filing and shaping though ... again ... I'm trying to work on a lot of projects at once ... not my strong suit.

Colin

Wingnutz · March 27, 2013, 05:03:18 PM

Your power system photos show a model that's deserving of the Beast title too! Spectacular!

Papa · March 27, 2013, 05:54:01 PM

That's some serious right thrust, She looks wonderful, you will have to let me know when the maiden is planned so I can put it in a tickler! Maybe even sell tickets for the Field Maintenance Fund. You should be very pleased with your self this has been quite the slog.

Jack.

wollins · March 28, 2013, 09:56:54 AM

Thanks Bill!

Quote from: Papa on March 27, 2013, 05:54:01 PM
That's some serious right thrust, She looks wonderful, you will have to let me know when the maiden is planned so I can put it in a tickler! Maybe even sell tickets for the Field Maintenance Fund. You should be very pleased with your self this has been quite the slog.

Jack.

Nah there's actually not a lot of right thrust ... it's an optical illusion because of the camera angle. I'm actually thinking I may need more right thrust because of the gigantic prop and it corresponding torque forces ... but I'll wait for taxi tests to make that call. If it pulls too much to the left on my mock runouts I'll adjust it.

As for the maiden ... as I mentioned before that's a looong ways off since I tend to get rusty thumbs when i haven't flown for a long time (ie: over winter) and I won't trust myself with this until I get back into the groove. Besides ... it'll be done alone (less pressure and nerves) with no fanfare, so you'll have to settle for getting a success or failure report after the fact for the Tickler!

Colin

wollins · March 28, 2013, 10:25:14 AM

Ok now we come to the second more scary part of this build for me ... the cutting of the cowl!

How's the saying go? Measure twice and cut once? Well I've been know to measure a million times and still cut wrong, so fingers crossed.

This cut is gonna be the actual hatch ... and its supposed to match the opening (battery bay) in the fuse itself. (cut much earlier) Normally I just use the piece that I cut out as the hatch itself, but unless you cut it with a a razor thin blade and perfectly straight you always end up with a raggedy hatch because of a somewhat imperfect cut.

The lines aren't clean enough so that when you reinstall it again as a hatch there are some small imperfections/gaps in the borders. I want this be be a perfectly snug fit so you'll notice from the pics that I actually am in the process of making a FG hatch in the likely case that I botch the cut as I've described above.

Typically, to make a perfect cut I would use a steel edge as a guide and then score the material with a sharp blade (eg: razor blade or #11 hobby blade) enough times so that eventially when I do cut through its an extremely thin and clean, precise cut.

However THIS cowl is about three layers of thick (5 to 7oz?) FG so it would be almost impossible to cut it with my scoring method ... and the curve of the cowl is such that I wouldn't be able to use my steel edge "guide" since it can't flex for that much of a curve.

So ... I'm just gonna dremel cut it with a cut off wheel which will probably make a cut with a corresponding 1/16" of a gap. However I'll then just cut and sand my replacement hatch to perfectly fit the hole I've made.

That's the plan anyways!

Working on that this morning so should have some news as to how it all turned out today sometime. Stay tuned!

Colin

wollins · March 28, 2013, 02:46:08 PM

Here's a pic of the right thrust Jack ... I'm really thinking I need more now that I see this with the laser!

Colin

wollins · March 28, 2013, 03:08:00 PM

Ok ... I'm done ... let me just say this. This worked out better than I could ever have hoped for. I'ts amazing what you can do if you have PATIENCE!

Anyways, I'll list it pic by pic with descriptions to go with each one explaining the process.

Pic #1: Held my breath, crossed my fingers and did the cut of the hatch ... came out really straight even though I free handed it with the Dremel. You can see the big gap I spoke of previously created by the thickness of the dremel cutoff wheel. Still ... I had made provision for that with my FG hatch that I fabricated so I'm VERY pleased.

Pic #2: Shows the actual cutout with the edges cleaned up.

Pic #3: YES!! It fit perfectly over my battery bay. My million times measuring this paid off for once!

(At this stage the edges weren't cleaned up yet)

Pic #4: FG hatch released and cleaned up prior to final fitting and trimming. Shown here next to the piece I cut out. I used three layers of 5oz cloth and it came out exactly the same thickness as the rest of the canopy! Whoo hoo!

Pic #5: FG hatch overlaid and taped over cutout so I can mark the exact cut lines from the inside of the cowl. (I used an extremely sharp pencil to get the thinnest line possible)

Pic #6: The finished product! This is the result of me cutting juuuuuuusssst outside my cut lines and then sanding and fitting about fifity or sixty times to get it just so. That's what I meant about the patience bit. lol!) BTW, what you see is it sitting inside the cutout, not resting on the canopy.

I am esctatic ... you gotta love it when a plan comes together!

Colin.

piker · March 28, 2013, 04:02:40 PM

Very nice! Did you leave room for a flange?

wollins · March 28, 2013, 04:18:36 PM

It'll be on the underside.

Papa · March 28, 2013, 08:07:49 PM

That is extremely neat, well done!

Jack.

wollins · April 01, 2013, 04:26:19 PM

Thanks Jack. Finally got some time to get back to the plane today ... finished up the hatch support and attachment issues ... decided to go with rare earth magnets for a clean attachment.

With the supporting frame attached it distrorted the hatch itself a teeny bit so the fit is not as precise as before but its good enough that when painted people won't even be able to tell where the hatch is.

Still haven't decided what to use "grip" it for removal ... using this screw for now until I decide.

Colin