Colin’s Spanish Fury

[Danny Fenton]

I think I must have made assumptions that all 5065 motors were a similar size, sorry about that chaps

I thought 50 was can diameter, and 65 was can length. (or vice versa) all of my 5065's are identical size and I swap them around between airframes depending on the KV I want.

That motor looks longer than 76mm Colin, I measured from where the prop would sit, to where the cruciform would mount.

If you change the position of the mount then you will lose the battery box......

IMO 100 Watts to the lb is not applicable to large props, they are more efficient, if you have over 900 Watts you will have plenty! And I will be using a 20" plus prop

Cheers

Danny

[Martin Fane]

Hi Danny

So you think the 320Kv motor on 5s with a 20 inch prop should produce 900 plus+ Watts and be OK ?

Just the dimensions to consider.

For info, the PO-5065-360 does seem to have the same dimensions you quote so maybe a rebadged Turnigy ??

cheers

Martin

[Colin Leighfield]

Jose, mine is 76 also!

Martin, hadn’t really thought about it but I wouldn’t have expected it to be that heavy, I would have guessed more like 8. However looking at Dirk Van Mourik’s build article (with a Laser 120) he said 4,300 gms, 9 lbs with 10 ozs/260 gms of nose weight. However his maths seem odd to me because 4.3 kgs. is 9.5 lbs using the 2.2 lbs/kg that I understand. Having said all of that I can’t see the original flying with a Merco 61 at 10 lbs, I would have thought 8 was more like it. No doubt if Danny is watching he will comment on this, I will be surprised if he has got this wrong.

[Colin Leighfield]

 I’ve only just noticed Danny’s reply and am concerned to read his comment about the battery box! In fact measuring from the prop driver face to the back of the motor where the cruciform sits, mine is 86mm! £50 with HK down the suff?

Edited By Colin Leighfield on 16/11/2018 17:23:31

[Danny Fenton]

Martin the 320KV might not be enough, 900 Watts is where i would want to be with the model coming in at anything up to 10lbs. I really hope to be closer to 7 for mine, but I know my models do tend to come out light, it's the foam

You may have to think about upping the cell count by one.

If you can fit the longer motor then you are okay. The cells can go directly behind F1.

the aerodrive 5060 or even 5055 might be a better choice, if you can get a suitable KV, but I am unsure if the lengths will work. they are both much lighter than the "new" 5065 which is more motor than is needed

[Colin Leighfield]

Measuring as Danny suggests mine is 86mm long and laying it on the plan confirms that I have to lose 15mm from the front. No problem to do that but I hadn’t even thought about it. I’m guessing that I will go for 5S 5000mah and get prop rpm somewhere about half way between 270 and 350. Better look at battery sizes and work out where they can go!

[Martin Fane]

Colin

From hobbyking PROPDRIVE v2 5060 380KV Brushless Outrunner Motor looks just right ?

Aavailable in the UK warehouse too.

Martin

[Colin Leighfield]

Hi Martin. Just looked at it and it seems fine. I find it difficult to make a perfect decision on this, but I’m going to have a look later to see if there will be any battery issues (using 5S 5000 mah Lipo) and if that is ok will stick with what I’ve got. I will see where I might be able to use blue foam and keep an eye on the weight from now on.

[Colin Leighfield]

Apart from sticking the fuselage sides together with F1, 3&4 I’ve haven’t been able to do any building tonight. However even with 15mm cut off the fuselage sides at the front I can’t see why there should be much difficulty in finding space for a 5S 5,000 mah Lipo, or am I missing something?

That is assuming that the combination of this motor, 5S 5000 battery and 20x10 prop are ok for this plane? That is where I am heading.

[Danny Fenton]

Colin, bolt the motor to a work-mate, and strap a 5S to it a selection of props and cells should give you the info to make a good decision. If you need help give me a shout.
Cheers
Danny

[Colin Leighfield]

Thanks Danny. This is a step up for me with electric though, I don’t have anything above 4S, so I need to buy the stuff anyway. Starting point seems to be a 70A ESC as advised by you and 20x10 prop with the 5S 5000 Lipo and fingers crossed, so I will place an order and do what you suggest.

My thoughts on the undercarriage are developing further as well.

[Jose L. G.]

Hi Colin.
The spanish version has a longer nose so you can put the motor you have and adapt the cowl.
Jos? Luis

Edited By Jose L. G. on 18/11/2018 09:43:55

[McG 6969]

Hi Colin & José,

Following the docs I have, I'm not that sure that the Spanish cowling has a different 'length' than the Mk1.

Obviously it looks quite different with the siamese Hispano exhaust ports and its elongated cylinder blisters. Also different carbs intakes, sidewall louvres and a small ventral scoop.

If you want I can have both profiles 'superposed' to compare them.

@ Colin > if you have to bring your ply motor mount back for 15mm, why not keep your standard ply F1 with blind nuts and have some threaded studs to support your crucifix mount? This would give you the freedom to adjust your spinner/cowl gap as needed and to use whatever length of motor in a possible future.

Just another daft idea, I presume...

Cheers

Chris

[Colin Leighfield]

Hi Chris. As far as I can see the cowling is the same length and profile. The cylinder “bulges” are longer and some differences in the air intakes. Easy to adapt the existing cowl without any major surgery. The radiator is different, smaller and more modern.

Your suggestion about the motor is one of the solutions, although the replacement balsa F1 is already glued in place! I have ordered the Lipos and ESC so I can work out where everything can go before I decide the final solution for the longer motor. I have already shortened the fuselage sides by 15mm and glued the ply motor mounting plate in place, fait accompli! I don’t mess about, just kick the can a bit further down the road and sort out a different problem later!

Here is my further thinking on the u/c. It uses exactly the same wire bend for the front leg as on the plan and rotates the same way. However the wire is 6 not 8swg. I’m not completely sure about the brass clips for fixing it to F3, thinking about that. The second leg is a different bend from 8swg. It is locked into a 3mm ply box the full width of the fuselage at that point and with the extended box lid slotting into the fuselage sides. The whole lot epoxied and probably with some external support such as triangular balsa. The box will be filled with strips of rubber cut from cycle inner tube, which s very resilient. Held together with rubber solution in the right places. Rubber is a perfect spring with natural damping. As I have drawn it, a little forward movement is available but the bulk of it is rearward. Combined with the resilience of the excellent Dubro tyres and some lateral spread of the u/c, I think it should work. Hung for a sheep,or a lamb, here I go!

[Colin Leighfield]

Just trying to work out if the undercarriage clips are in here? Can’t see them.

[Colin Leighfield]

What’s wrong here? Is it me?

[Jose L. G.]

No. The problem is the former. Do you have the drawing from Danny?
Jos? Luis

Edited By Jose L. G. on 18/11/2018 17:02:09

[Danny Fenton]

Have you not been following the threads Colin?

If you haven't got the pdf let me know

[Colin Leighfield]

Thanks Jo, Danny. Yes, I’d forgotten. I printed off Danny’s corrections, no problem.

[Jose L. G.]

Colin.

On page 45 of the main thread Ernie posted a pic identificating the etched pars.

Cheers

José Luis

[Colin Leighfield]

Jose, thank you. I had missed that.

Cheers,

Colin.

[Colin Leighfield]

I want to make sure that I have fully sorted out the detail of undercarriage mounting, as well as battery and ESC position before I finish the fuselage. I intend to complete the undercarriage to dummy fit stage this evening. Here is the completed front leg, as mentioned before made from 6 swg wire instead of 8 and with 3 hinges instead of two. Second leg this evening and I hope to have it soldered up so that I can check out the practicality of my rubber based shock absorber idea, which I am quite confident about.

[Colin Leighfield]

Just a warning about the need to wear eye protection when using cutting discs. I used the Dremel to cut some of the brass bits out when this disc flew to bits and hit me just above the eyebrow. There wasn’t much of a hit because it was so light, but even so of it had gone into an eye it could have been nasty.

Also in considering the undercarriage options I dug these out. Somebody made them when I was in the Tamworth club, I can’t remember who. Must have been 35 years ago! Excellent progressive spring movement and the right length. However the top diameter of 20 mm and bottom 15mm are simply too wide for the leg fairing, which is about 12 at the top and 6 at the bottom. I could do it but it wouldn’t look right so I will stick to plan B.

[Colin Leighfield]

I wanted to make sure that the undercarriage idea is practical and it looks like it. Also the 5S5000 mah Lipos have arrived, rather large !

[Colin Leighfield]

Managed to get a few hours in today, still trying to work my way through the fuselage. After the still unfinished business with the frustrating Chipmunk I said I wouldn’t look at Mr. Bryant’s designs again and this is reminding me why! That’ll do for tonight, I’m going to have another look at the build threads and see what I might be missing. I can identify one blunder already. Work tomorrow I’m afraid.