Ripmax P-51 anyone?

[Tim Kearsley]

Yesterday I took my beloved Ripmax Spitfire up to the field to try out some new Nano Tech LiPos I recently bought.  The batteries perform extremely well, but.... I wrote off the Spitfire!!  It was pure and simple pilot error and I'm absolutely disgusted with myself.  There was no need for it, no excuse for it and it was downright STOOPID!!

 

I'm going to replace it, but I'm thinking why not have a change?  I'm attracted to the Ripmax P-51.  I'm assuming that the MVVS 3.5/1200 motor that I had in the Spitty will transfer into the P-51 without issue but can anyone confirm that the mounts etc are the same?

 

Also, how does the P-51 fly?  The Spitty was an absolute delight - one of the nicest models I've ever flown.

 

Any opinions welcome chaps!

 

Cheers,

 

Tim.

[paul@scc]

Not as nice as the Spit to fly, but still a good flyer. You have to keep your speed up she is not as forgiving as the spit.

I got mine secondhand and motor was already fitted. I did look at a new one and the mount was totally different to the spit which I found odd. Instead of a box it had two rails, kind of difficult to describe. This was a couple of years ago, so maybe the design has changed.

[Romeo Whisky]

Well I have never had the Spit so cannot compare, but I absolutoely LOVE the Ripmax Mustang.  It is the most beautiful thing in the air, and more scale-like than the Spit. 

 

Like many Spit owners, I wish it had undercart, and when I first flew it I was anxious about the radiator bath digging in on belly-landing and breaking props.  I needn't have worried.  It is a joy to fly and landing are just a matter of bleeding off the speed close to the ground and she lands sweet and smooth.  Love it.

 

 

[Romeo Whisky]

The motor mount is designed for a 600 can motor and the easiest fit is a 600 size inrunner which also makes it silky smooth and quiet.  Mine is powered by a Mega 22/20/3e (1500Kv) which is not cheap but worth every penny.

 

I've done a review on this forum which gives a bit more detail.

Edited By Romeo Whisky on 01/09/2010 19:37:55

[Tim Kearsley]

Thanks very much for the comments RW.  It sounds to me then that my MVVS motor will be OK, as it's fairly similar to your Mega motor I think, both in dimensions and weight.  Your Mega is 1500 kV and my MVVS is 1200.

 

[Romeo Whisky]

Tim,  I think you'll  be fine with the 1200KV MVVS and LiPo because I fly mine on LiFe battery packs which are lower voltage than LiPo.

 

Remember to put in a wire torque-rod to strengthen the join between the two elevator halves.

[Tim Mackey]

The motor will be fine powerwise etc, but the mounting is still the old rail style ( not like the spitfire )

Personally I like the spitty better - have flown and "built" both - the Spitty certainly slopes better I reckon.

[Tim Kearsley]

Thanks for the comment Tim.  I too found the Spit a delight to fly, and I'm so annoyed that I destroyed it in a moment of stupidity!  I might just replace it with the same again.  Am I right in thinking that the Ripmax P51 has no rudder control?

 

[Romeo Whisky]

No TK, the P51 DOES have rudder control.  Tim M's reference to the motor mount is irrelevant in the case of your motor, becuase it is desiged for an inrunner which just sits neatly between two clamps (provided in the kit) on the mount rails.  So provided your MVVS is the same dimendions as my Mega, which you say it is, it just pops straight in with no mods (although having read comments about the Spit motor mount being weak, I did reinforce it with a few extra filets of ply).   It is a personal choice of course, and TM has flown both (as slope-soarers only?), but for me the Ripmax Spit was just too far off scale to look right for me.  The cowl particularly put me right off it.  Each to his own I guess.

[Kelly]

Off scale

 

Looks good to me

[Romeo Whisky]

If you think that cowl is scale Kelvin, I can only presume you have never seen a Spitfire.

 

I agree it is a very nice model and I've seen one fly, which it does very well and looks very nice in flight.    It even looks quite a lot like a Spitfire.   

 

But scale it ain't.

[Kelly]

Yep tis but semi-scale, still better than most of its class.

 

Yes I have seen a Spity close up,this is me sat in one .

 

[paul@scc]

Posted by Kelvin on 04/09/2010 09:55:56:

Off scale

 

Looks good to me

 Is that the cowl that comes with the Ripmax Spit. If it is then they have changed it because the original was awful.

[Kelly]

Hi Paul

 

It is the original with the false spinner bit chopped off, commercial spinner in its place and more scale like exhaust stacks carved out of scrap balsa.

 

Bit of camo paint and panel lines plus underwing radiators etc make a much more convincing profile in the air

 

I like the mustang and the Bf109

 

My  Ripmax 109

 

Bits added.panel lines etc. bit more convincing than the stock item

 

Kelvin 

[paul@scc]

Hi Kelvin. That is a great mod on the cowl, looks a 100 X better. Your 109 looks good too

 

I have had all three of the Ripmax models and loved flying them all. Alas due to dumb thumb moments they no longer grace the skies. One of these days I will have all three back in the hangar

[Tim Kearsley]

Romeo Whisky - did you find any problem in fitting the cowl when you built the P51?  I mounted the motor as per the instructions, so that the front edge of the motor is 85 mm from the front edge of the firewall, but the cowl won't sit far enough back to allow me to get the spinner et al mounted!!

 

Just wonded if you encountered the same problem and what you did if so.

 

Cheers,

 

Tim.

[Romeo Whisky]

It is quite a while ago now Tim, but I don'r remember having a problem.  I did reinforce the motor mount rails with some triangular ply side pieces, and I must admit I spent quite a lot of thinking time about the motor mount situation, but in the event I think it was very straightforward.

 

However like most people I did not use the dreadful spinner that came with the model, but used an Irvine spinner with aluminium backplate.  These are beautifully made and balanced and the backplate has airflow holes to help with cooling.

 

I don't recollect ever taking the cowl off since building it, but I'll do that and photograph it for you and post it on this thread.  Might be tomorrow before I can get round to it though.

[Tim Kearsley]

That's very kind of you, and that would be most useful - thank you.  I too have bought a decent spinner - a Graupner one for electric - but at the moment I can't see quite how I'm going to fit the collet prop adapter to the motor shaft without moving the cowl back quite a bit - if indeed the cowl dimensions will allow it to be moved back that far.

 

[Tim Mackey]

I did the P51 for a mate recently and we fitted an outrunner with a shortish shaft.

We ended up fitting a wooden spacer and then a round former onto the ends of the bearers, and then fitted the motor to that ( from behind IYSWIM ) to ensure sufficient shaft protruded in order for the collet style prop driver to fit well.

Edited By Tim Mackey - Administrator on 16/09/2010 11:20:09

[Kelly]

Hi Tim K

 

Build blog with pics of brushless motor mounting modification

Ripmax P-51 build

 

Kelvin

[Tim Kearsley]

That's extremely useful Kelvin - thank you very much.

 

Tim.

 

[Romeo Whisky]

As promised, here are some pics of my motor mount and cowl alignment.  I've created a new album for these and there are some more to view there if you wish.

 

[Tim Kearsley]

Thanks very much RW.  I see now that the difference is in the spinner and method of prop attachment you and I are using.  My spinner has a collet type prop adapter with it and requires most of the motor shaft to be standing proud of the front of the cowl, in order for the collet to have something to grip.  Is your prop adapter a grub-screw type?

 

[Romeo Whisky]

Tim I vaguely seem to remember that I also initially bought a Graupner spinner with integral collet because I had been so impressed with the quality of the one I had fitted to my Overlander Tucano.  But  I was unable to fit it to the Mustang (it's still in my bits box), and that is why I bought the Irvine spinner which is much lighter (and I do like the airholes for cooling).  It uses a standard collet type prop adaptor but the spinner backplate does not have the "skirt" round it (as the Graupner does), so it is a perfect flush fit.

Edited By Romeo Whisky on 17/09/2010 08:43:54

[Kelly]

I agree,  Irvine spinners are great .