EarlyBird Posted February 16, 2021 Share Posted February 16, 2021 Looking at the drawing compared with what you have it looks to me that the axle is too long and the spat is too high. Cutting the axle down close to the collet should allow the spat to sit lower as in the drawing. Which is your plan anyway. Steve Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 16, 2021 Share Posted February 16, 2021 How exactly do they expect that to mount? If the axle is supposed to pinch the spat and hold it in place then it will eventually rotate around as the landing shocks will crush the wooden plate in the spat and then the whole thing will come loose. I recommend you at least drill one (2 ideally) holes through the ali undercarriage leg so that two screws can pass through the leg and hold the spat in place so i cannon rotate even if loose. Its not a nice setup though. I would bolt the wheel up tight without the spat, then modify the spat to drop over it and retain it with the two screws i mentioned earlier. My Hangar 9 pulse's used this method and it was worked very well. Quote Link to comment Share on other sites More sharing options...
GrumpyGnome Posted February 16, 2021 Share Posted February 16, 2021 Jon's solution sounds good but personally, if you fly off grass, I'd leave them off as they just collect grass/worm casts/dirt/general detritus and slow the plane down. I know it'd look nicer with them on but it's one (two?) less things to worry about. GG Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 16, 2021 Share Posted February 16, 2021 I've had models with those type of spats/fit, they do nip up tight, but occasionally they will rotate a little, no biggie to realign them. Having said that, mine go in the drawer. Quote Link to comment Share on other sites More sharing options...
kc Posted February 16, 2021 Share Posted February 16, 2021 I noticed that you showed an 11 x 5 prop in your photo. The OS 40FP won't rev but it will turn an 11 x 7 prop and that's the correct prop to use - everyone may say that's wrong but it's correct (at least for most versions of the 40FP) See the engine tests at the time. I was disappointed with my 40FP until I studied the engine tests and realised it would turn a large prop. Of course the 11 x 5 will work but it won't do any more revs, so the 11 x 7 will give more power. Quote Link to comment Share on other sites More sharing options...
Russ P Posted February 16, 2021 Share Posted February 16, 2021 I've just completed building the Challenger kit now starting to cover it. I previously had the ARTF version for 3 years, was my go to model for a bit of fun, flying too low and fast hit the ground! Bought the kit at the start of lockdown for something to do. Don't bother with the wheel spats as has previously been said. I had an OS 55AX in mine no additional weight required for c of g, the build instructions say 46-2 stroke or 70-4 stroke. There is and good videos build on youtube (link below) which takes you through the build, the booklet that came with the kit has a few points missing or in the wrong sequence. If its your first kit build it would be worthwhile looking at the videos. 1 Quote Link to comment Share on other sites More sharing options...
Russ P Posted February 16, 2021 Share Posted February 16, 2021 Sorry, just seen the date of the original posting, probably built it by now. Anyway good practice using the new website. Quote Link to comment Share on other sites More sharing options...
Gsky Posted February 21, 2021 Author Share Posted February 21, 2021 Hi guys, I decided to enter the realm of aero modeller and do some mods to make the spats fit. Just trimmed the axle and epoxy glued some M3 nuts on the inside so I could fit some extra M3’s to the spat. Not the lightest solution but feels solid. 1 Quote Link to comment Share on other sites More sharing options...
Gsky Posted February 21, 2021 Author Share Posted February 21, 2021 On 16/02/2021 at 16:47, kc said: I noticed that you showed an 11 x 5 prop in your photo. The OS 40FP won't rev but it will turn an 11 x 7 prop and that's the correct prop to use - everyone may say that's wrong but it's correct (at least for most versions of the 40FP) See the engine tests at the time. I was disappointed with my 40FP until I studied the engine tests and realised it would turn a large prop. Of course the 11 x 5 will work but it won't do any more revs, so the 11 x 7 will give more power. that’s good to know! Will have to give an 11x7 a try. I just went with the OS manual but haven’t done much research into it Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted February 21, 2021 Share Posted February 21, 2021 Looks good to me ? Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 21, 2021 Share Posted February 21, 2021 Jobs a gud un Gsky, did you remember the thread lock on the nuts ? Quote Link to comment Share on other sites More sharing options...
Gsky Posted February 21, 2021 Author Share Posted February 21, 2021 On 16/02/2021 at 17:28, Russ P said: Sorry, just seen the date of the original posting, probably built it by now. Anyway good practice using the new website. Hi Russ actually I’m still building this one. taking it easy as I bought this kit as my first plane so been trying to build up my flying experience before flying this one. I’m not far off pretty much on the covering stage too but I decided to make life difficult and add some navigation lights too. Quote Link to comment Share on other sites More sharing options...
Gsky Posted February 21, 2021 Author Share Posted February 21, 2021 2 minutes ago, john stones 1 Moderator said: Jobs a gud un Gsky, did you remember the thread lock on the nuts ? Thanks John. Good reminder! I haven’t yet just checking it all fits but I think we are good to go. 1 Quote Link to comment Share on other sites More sharing options...
Gsky Posted October 19, 2021 Author Share Posted October 19, 2021 (edited) Very close now, did some taxi tests and really happy with how it’s turned out so far. Last thing now is the c.g still too tail heavy and that’s using a c.g of 75mm from the LE (manual says 60mm). needs ~100g at the engine to balance with an empty tank. Could I move my battery to sit under the motor? That way saving adding an extra weight? 5700707_taxitest.mp4 Edited October 19, 2021 by Gsky video updated to mp4 1 Quote Link to comment Share on other sites More sharing options...
Gsky Posted October 19, 2021 Author Share Posted October 19, 2021 Quote Link to comment Share on other sites More sharing options...
Jon H Posted October 19, 2021 Share Posted October 19, 2021 i wouldnt recommend strapping a battery to a hot, oily and vibrating lump of metal. Mount it as far forward as you can and then just bung some lead in it. Its not a vicious model so c/g is not as critical as with a warbird or an aerobatic model. Quote Link to comment Share on other sites More sharing options...
Gsky Posted October 20, 2021 Author Share Posted October 20, 2021 Yes makes sense, I think I will just make a hatch under the fuel tank to fit the battery. Tried to fit it through the formers but doesn’t go through. Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted October 20, 2021 Share Posted October 20, 2021 (edited) Have helped fit out a Challenger recently, And my newbie builder was tempted to form a hatch where you propose to fit an hatch But there must be 90% of the nose strength there our solution was to cut through some of the forward tank floor inside and the battery fitted there and save a few ounces of nose weight not added for C of G Edited October 20, 2021 by Denis Watkins Quote Link to comment Share on other sites More sharing options...
Gsky Posted October 20, 2021 Author Share Posted October 20, 2021 Yes that’s what I was thinking my only concern is that the balance lead is short and so I would need to remove the fuel tank every time I want to recharge. Unless I can find an extension for the balance lead Quote Link to comment Share on other sites More sharing options...
Jonathan M Posted October 20, 2021 Share Posted October 20, 2021 https://www.4-max.co.uk/balance-adapters-extensions.htm Or use a standard NiMH flight battery instead of the LiFe one. Quote Link to comment Share on other sites More sharing options...
Gsky Posted October 22, 2021 Author Share Posted October 22, 2021 Thanks Jonathan, that looks perfect. Hopefully Will start cutting over the weekend Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.