# Clanford Clan 0.24cc Aero engine



## creast (Aug 17, 2019)

Hi Guys,
Its been a very long time since I did a build log (last was the Vega V-twin) but I have decided to for a simpler but probably very challenging go at the Clanford Clan.
This is from the 'Motor Boys' plan book and looks a real cutie!
I have created a 3D model to check out the plans and is posted on 
https://grabcad.com/library/clanford-clan-0-24cc-aero-engine-1

First bite is the crankcase (pics to follow)

Has anybody here built one?

Cheers
Rich


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## rklopp (Aug 17, 2019)

I built one. It is one of my favorite “diesels,” and I have build guide a few. It starts and runs quite easily.


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## Billitmotors (Aug 18, 2019)

Can I make a suggestion .  The crankcase has a small counterbore to align the cylinder  and there are only two screws to hold it all together .
I would  put a small stepped flange at the bottom of the cylinder to give a better bearing or sealing area.  I found it very difficult to tighten everything so it didn't leak crankcase pressure.
Also don't let your screw holes break through into the crankcase, again, loss of crankcase pressure.
Good luck with the build.


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## rklopp (Aug 18, 2019)

FWIW I did not have problems with crankcase leaks. I made my own screws, which probably fit tighter in the tapped holes than commercial screws. I may even have single-pointed them; I forget. The cylinder-crankcase joint should not leak provided the fit is snug, the surface finish is decent, and no burrs or chips are caught in the interface.


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## creast (Aug 18, 2019)

Thanks Guys,
Any information/experiences would be most useful.
I just started machining the crankcase.

rklopp, your engine looks lovely! What did you make the fuel tank cap from?


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## creast (Aug 18, 2019)

Billitmotors said:


> Can I make a suggestion .  The crankcase has a small counterbore to align the cylinder  and there are only two screws to hold it all together .
> I would  put a small stepped flange at the bottom of the cylinder to give a better bearing or sealing area.  I found it very difficult to tighten everything so it didn't leak crankcase pressure.
> Also don't let your screw holes break through into the crankcase, again, loss of crankcase pressure.
> Good luck with the build.



Lovely looking motor!!!


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## creast (Aug 18, 2019)

Well, today I started on the crankcase from 6082 T6 bar stock.
Its a long time since I did any thread turning on my ML7 and the tipped threading bar I had just cleared the bore. I think it has gone OK and wish I had turned a male thread part first! Oh well, will make it fit 
Transferring the chuck to my rotary table is a first now I have a Myford adaptor plate. However, my mill, which is a Dore Westbury, had to have its head cranked high so I could run a DTI in the chuck and once set you can't move the head up or down without losing alignment. This meant rigidity was poor due to the head height.
Anyway, I have roughed out the profile and will square up the lugs later.


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## rklopp (Aug 18, 2019)

creast said:


> Thanks Guys,
> Any information/experiences would be most useful.
> I just started machining the crankcase.
> 
> rklopp, your engine looks lovely! What did you make the fuel tank cap from?



The black part is Delrin (might be generic acetal) and the clear part is acrylic.


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## creast (Aug 19, 2019)

rklopp said:


> The black part is Delrin (might be generic acetal) and the clear part is acrylic.



Can you tell me how the two are joined? Are they glued?
Also, I see two holes in the top of the Black Lid part which I am guessing are for filling and breathing. Is the larger hole plugged when in use?
Thanking you in advance . Rich


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## creast (Aug 19, 2019)

Today I squared up the mounting lugs and drilled all holes. I decided to go M2 rather than 9 B.A as its close and the fasteners are more readily available. Plus I don't have a 9 B.A tap!
The bore and recess detail are 7.5mm dia and 8.5mm dia  and I don't posess either drill or end mill of these sizes so decided to make a turning fixture to allow boring of these details which will be more controllable anyway.
Its amazing how much time is involved just hold things!


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## rklopp (Aug 19, 2019)

creast said:


> Can you tell me how the two are joined? Are they glued?
> Also, I see two holes in the top of the Black Lid part which I am guessing are for filling and breathing. Is the larger hole plugged when in use?
> Thanking you in advance . Rich



The fuel tank and top are snap-fit using a little ridge and groove arrangement. The holes are indeed fill and vent. I do not plug either one when running. This engine has not flown and probably never will, so I have no concerns about spillage.


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## creast (Aug 20, 2019)

rklopp said:


> The fuel tank and top are snap-fit using a little ridge and groove arrangement. The holes are indeed fill and vent. I do not plug either one when running. This engine has not flown and probably never will, so I have no concerns about spillage.



That sounds like fun?? Can see plenty of trials to get that fit right.
Oh well, all to be tackled later 
Thanks!


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## creast (Aug 27, 2019)

Progress has been slow due to other household work requiring attention and will be robbing me of my "playtime" as my other half refers to.
Anyway, despite promising myself to do all the aluminium bits I made the cylinder head and the spinner before diverting to the crankshaft.
Having just checked, I realise my spinner is probably wrong to drawing but I may stick with it anyway (senior moment I think)
I chose to use EN24T for the crankshaft as this is a strong alloy steel but I really struggled to get a got finish. In the end I used my DIY toolpost grinder of sorts to near finish the shaft and finally polish with 1000 grit abrasive.
The fit is still a little tight but can be tweaked later.


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## creast (Sep 6, 2019)

Well, after another excursion, I am back to creating 'swarf' 
After roughing out the cylinder in EN1A steel, I silver soldered the inlet port to it and machined in the ports.
With hindsight, I think for a future build I would silver solder onto a near finished bore and then trim the lengths to suit before machining the ports.
Lapping has resulted in a slight oversize of the specified bore but I will, hopefully, match the piston to suit.
Machining the backplate was a bit tricky and threading was actually done by rotating the chuck by hand as the undercut runout is very tight!
To produce the slot for tightening involved making a custom cutter as I didn't have a 1mm mill or circular cutter. I actually used a 1.3mm drill shank and it worked fine... only 0.003" cuts!


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## creast (Sep 15, 2019)

It seems I haven't achieved much this week.
I have finally made the Con-Rod, piston and contrapiston and not without much pain in the process!
As I have said previously, most of the time is in making fixtures and custom tools to actually achieve all this.
I did not posess a 1.5mm reamer for the little end details so had to make one from a drill shank (See Clickspring on YouTube for details)
Lapping of the cylinder took many hours but I think it's ok. Slightly tight but I followed Ramon's method using a copper expandable lap.
On a trial assembly I have noted the con-rod fouling on the crankcase opening or maybe the cylinder and on checking the CAD model I can confirm that to be the case so I will have to take a little more off the con-rod cross section to about 2.8mm rather than 3mm.
Addendum- Since reading Mark Lester's build notes I can confirm this interference has been noted before.


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## creast (Sep 16, 2019)

Today was spent modifying the chamfer to 40 degrees in the cylinder base to gain more clearance as with reducing the con-rod thickness .
I ended up wrecking the cylinder head when drilling the two screw holes as my DRO gave a false reading. Grrrr!!
Two tries later I managed to finish a new one and a trial fit showed all is well.
This is a more finicky job than expected!
Next is the carburettor.


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## creast (Sep 18, 2019)

I have been waiting a while for a delivery of clear plastic test tubes from China which I hoped would enable me an easy route to the fuel bowl.
My hopes were dashed a little when they arrived. They were 12 mm OD at the top but tapered to just over 11 mm at where I wanted to part them off. They also had a change of section witness line at the bottom.
Even worse was they were quickly attacked by the fuel. Time to re-think and maybe I will have to machine one afterall!
I also 3D printed the cap hoping that may be acceptable. The original was an injection moulded part and I wasn't too keen in being able to machine this from solid Delrin due to the complex cylindrical blends. However, the layer lines look naff and they are a nightmare to sand out at the best of times.
So... This may be described as 'being a bit anal' ... I am going to have a go at DIY injection moulding the part!
I have made a 4 piece simple mould and am now making an ad-hoc extruder/injection tool.  I plan to use PETG as this appears to be resistant to Ether and Paraffin etc. (To be continued)


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## creast (Sep 20, 2019)

Well, it's been a frustrating couple of days.
My first attempts on injection moulding were plagued with poor fills and difficulty removing the moulding intact.
Then the thermocouple failed...aaarrrrgggh!
I had hoped the shrinkage of the plastic would negate the need for draft angles but was wrong. Coupled with the aluminium tooling needing pre-heat, this shrank more than the plastic.
So, I reverted to a PTFE mould and crude trials were very promising.
A mould was machined close to that of what is required and I couldn't resist having yet another go straight off to see if any problems lurked.
The design is not necessarily final and would require the part to be finish machined as would the bores etc as I fear I would never get any inserts back out!
The extruder is made from modified plumbing parts and a simple hand plunger mechanism. A 125W band heater does the heating.


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## creast (Sep 29, 2019)

After a break in Spain I returned to the problematic carburettor cap.
Injection moulding was encouraging but not the answer. The threading of  the PETG plastic for the manifold thread was simply awful.
There was also the weakness of the M2 thread for the needle valve so I regret I have to diverge from the plans.
I did try moulding with an insert thread for the inlet manifold but I was still not happy.
I admire anyone who has machined this part in plastic or even metal! Its a pretty awful shape and size to tackle as one piece.
So..its going to be in Aluminium and I really believe this is a best option since diesels can get pretty hot and I did fear for the plastic thread.
I have included a couple of the last moulding pics just for historical purposes.


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## Bazzer (Sep 30, 2019)

Creast

An interesting project and some nice work to produce various parts.

With regard to the carb cap , did you consider printing it in a vertical direction? Maybe make a sacrificial base where the cap fits to the engine to give stability on the printer bed.

This way you would only be left with significant lines on the bowl diameter which would be much easier to clean up. The lines on the tube above the bowl in your photo would be tricky to clean up nicely.

Does PLA melt with ether and parrafin? If not you should try the CF filled PLA from Proto Pasta, it gives fantastic results and can be heat treated to resist approx. 140 deg C.

Regards

Barrie


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## creast (Sep 30, 2019)

Thanks for the comments Barrie,
Although I am resigned to go the aluminium option (I have machined/fettled one at the moment),  I will give your suggestions a try and see how it prints.
I did consider doing a lost PLA casting from the 3D print which is a technique I have used quite a bit and you can dress out the layer lines easier on metal.
I did look up the Ether/Paraffin resistance on Google and it indicated it was ok to use. I have just popped a sample into some fuel to confirm 
Thanks for the note on CF filled PLA, I will check it out.
Cheers
Rich


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## creast (Sep 30, 2019)

Quick update.
I just tried printing the part as Barrie suggested and it does show some promise apart from some weird print artifacts in a couple of places.
At this size the prints look reasonable by eye but as soon as you zoom in on a photo they look terrible.
I did try to print the M4 thread but the resolution of the printing is not really up to it (0.1mm layer height, 0.3mm nozzle).
It was easy to run a die over it though to at least size it a bit.
A sample of PETG has been in fuel for 3 hours now and shows no sign of distress. I will leave it a day or so to confirm.
I have also ordered a sample of the CF filled PLA to have a play with.


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## Bazzer (Oct 1, 2019)

Rich

If you send me the model I will print one for you to see how I get on? I think it is optimistic to print the thread, I think I would leave that plain and run a die over it to create the thread.

The CF PLA from Proto Pasta can be heat treated to resist 150 deg C, I don't think the Clan will get to that temp on the intake side !!

Regards

Barrie


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## creast (Oct 1, 2019)

Barrie,
Yes, I knew the printed thread would be a waste of time but hey, worth a try to see how the printer coped with it... not well LOL!
It's very kind of you to offer but as you see from the attached I have laboured away on the aluminium version which I hope to anodise black in keeping with the original (I know I'm not the first to go the alu route).
If however, from a curiosity point of view, you would like to try then I am happy to send you an STL or if you are a GrabCad subscriber you can find my Clan on there. 
Cheers
Rich


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## Bazzer (Oct 1, 2019)

Hello Rich
I have down loaded your Clan model and isolated the fuel tank cap.

Attached is a print of the cap, this was the second attempt, the first printed vertically had some drop out of detail due to no supports.

On the second print I layed the part conventionally and allowed supports under the flange where the fuel bulb sits and under the tube that screws into the engine.

Under the naked eye or mild magnification the part looks really quite good.













Clan_Fuel_Tank_Cap



__ Bazzer
__ Oct 1, 2019



						3D printed Clan 0.24cc fuel tank cap
					




However you are a quick worker and the metal part you have made is far superior to a 3D printed part.

Regards

Barrie


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## creast (Oct 2, 2019)

Barrie,
That's come out really nice!The print quality looks a lot better than mine.
I haven't refined the settings for PETG apart from temperature on my Anet A8 which has served me well for most of my requirements but is at the budget end of printers.
I have just received a sample length of the Carbon fibre PLA to play with which may suit other projects I have in mind. 
Did you use standard PLA settings?
Also, have you sussed a workaround for restoring finish on sanded prints (apart from paint). Black always goes the proverbial grey.
Regards,
Rich


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## Bazzer (Oct 2, 2019)

Hello Rich

I have used exactly the same settings with the CF PLA as normal PLA, I print at 220 deg C, with a 0.4mm nozzle and 0.1mm steps, I set a nozzle to bed gap of 0.075mm, for small parts I use 100% infill (solid), the printer is a Dremel 3D20 which my family bought second hand for my birthday.

I have only been printing with the CF PLA for a week now and to be honest all of the parts I have made have such a nice finish that I have not sanded them. I do know the greying that you mention from many other similar jobs. I would suggest that an easy thing to do would be to wipe the sanded surface with a medium viscosity cyanoacrylate adhesive (domestic super glue).

I tested bonding PLA with cyanoacrylate and it stuck like the proverbial you know what.

Regards
Barrie


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## creast (Oct 2, 2019)

Thanks for info and tips Barrie, I am looking forward to trying this material out soon.

Today I spent the whole morning trying to make the compression screw. It took me five goes to get one!
The problem was partly that I was using silver steel and this doesn't like bending cold so heating was in order. However, this also led to poor bend radii on several occasions. All manner of problems where it just didn't look right.
In the end I machined 4mm dia mild steel down to size and annealed the bend during forming and voila!
At this point I couldn't resist assembling the engine and seeing if it would fire up without the carb (still under construction).
I was really pleased that after some time of just squirting fuel into the ports and endless flicking it did actually run for a second or two on several occasions. Encouraging indeed!
Some bubbles from the compression screw thread indicates the contra-piston is not tight enough (which I suspected) and so I will make new.
After that it's time to start anodising


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## Bazzer (Oct 3, 2019)

I would be interested to know about your anodising setup? my anodising has been hit and miss, there must be something I am doing wrong.

B.


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## creast (Oct 3, 2019)

Barrie,
It's been quite a few years since I did any anodising so it will be a revised learning curve. 
The last time was the cylinders on my Ky-Ko sterling fan which turned out good. I used a commercial black dye then which I will use for the fuel cap.
The red is a new venture using Dylon fabric dye so fingers crossed. Obviously need to do some trials first.


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## creast (Oct 5, 2019)

Today was Anodising day (evening really).
I wasn't sure if the acid I used years ago was any good but I set up the bath and did a test run on a piece of scrap. 
The bath is just a plastic container with lead sheet as the cathode and aluminium rod to connect the part to anode.
Constant current of approx 100mA @ 15v for 1 hour.
All looked promising and the dye uptake with commercial black was pretty good so I went for broke on the carburettor cap and I am quite happy with the result. 
Next was the red dye which was a fabric 'Dylon' dye which proved disastrous as it obviously wasn't being absorbed into the pores. I hurriedly gutted an inkjet printer cartridge and dunked the part into it. 
Ok, its not red! It's magenta and the part is not the final spinner but it did show that inkjet dyes are a working solution so now I need to blend inks for the red. I also need to find a decent method to polish it too.


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## Billitmotors (Oct 6, 2019)

creast said:


> After a break in Spain I returned to the problematic carburettor cap.
> Injection moulding was encouraging but not the answer. The threading of  the PETG plastic for the manifold thread was simply awful.
> There was also the weakness of the M2 thread for the needle valve so I regret I have to diverge from the plans.
> I did try moulding with an insert thread for the inlet manifold but I was still not happy.
> ...


G’day Creast
When I made mine I machined the cap from delrin and then machined brass inserts which were assembled and then soft soldered in place. The biggest problem I found was finding brass tube small enough for the fuel intake and ended drawing it too the correct diamater using a drawing plate that I was given years ago and then having to drill it out using jetting drills because when you draw it through the plate it reduces the OD but the ID gets smaller as well.


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## creast (Oct 6, 2019)

Billitmotors said:


> G’day Creast
> When I made mine I machined the cap from delrin and then machined brass inserts which were assembled and then soft soldered in place. The biggest problem I found was finding brass tube small enough for the fuel intake and ended drawing it too the correct diamater using a drawing plate that I was given years ago and then having to drill it out using jetting drills because when you draw it through the plate it reduces the OD but the ID gets smaller as well.



I am impressed how well you managed to soft solder the parts in-situ, I have scrutinised your earlier photos you sent and am well impressed.
Also, re-drawing tube is another feat I have not ever undertaken. Great work!
I have chosen to use a hypodermic needle for my tube and finally chosen a glass fuel bowl cut from a test tube after underachieving a pure clear acrylic version by machining.

Rich


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## creast (Oct 6, 2019)

Anodising part 2.
Blending magenta and yellow inkjet inks 50/50 and diluting  3:1 with distilled water has proven to be a good dye option.
5 mins immersion was plenty enough followed by steaming for 2 mins and boiling in deionised water for 5 minutes .
From research, the 6082T6 alloy is prone to dull anodising apart from the fact I didn't polish the parts but I am happy with the results. 
The photo doesn't really do it justice and looks more like a paint finish.


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## creast (Oct 8, 2019)

It took me two goes to get the correct fit on the contra-piston but it is much better for it.
The carb was finally finished and the engine is complete.
I hope to have her running soon.


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## Bazzer (Oct 8, 2019)

Rich

Your engine looks really sweet with nice detail.

More than that I am impressed with how quick you get things done, great effort.

Regards

Barrie


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## creast (Oct 8, 2019)

Thanks for the kind comments Barrie.
It does help that I am retired and I do tend to get a 'bee in my bonnet' on some projects.
Rich


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## creast (Oct 8, 2019)

Update. The project isn't finished until it functions!
Three hours of flicking, priming and two propeller cuts later I think I am on track.
The engine would start fairly readily with priming through the exhaust ports but would only run a few seconds. Trying all the usual tweaks of mixture and compression didn't result in any improvement and I suspected the carb.
Luckily I found an old simple needle carb from an unknown engine and grafted it on.
Still not much luck!
In the end I found the engine would run if the tank level was slightly positive in head height and ran for over 3 minutes albeit slightly erratically.
To me this indicates either poor crankcase sealing or maybe poor venturi effect. I did seal the head screws into the case but maybe I need to check the rear cover and perhaps the cylinder to case sealing.
Having said that, the impromptu carb throat is probably too large but the one I made is definitely no good anyway.
Any ideas anybody?


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## Maris Dislers (Oct 8, 2019)

To me this indicates either poor crankcase sealing or maybe poor venturi effect. I did seal the head screws into the case but maybe I need to check the rear cover and perhaps the cylinder to case sealing.
Having said that, the impromptu carb throat is probably too large but the one I made is definitely no good anyway.
Any ideas anybody?[/QUOTE]

Yes. Definitely ensure against crankcase compression leaks. Also ditch the spring under needle and replace with tygon or neoprene tubing to provide seal and the desired friction. The design choke size is OK, but could be a little smaller. If you have run the tap into venturi choke it will be oversize. If your thread for needle does go through, you could make a fresh needle with extra thread almost to the point where needle taper enters the fuel jet. This will block part of the choke and improve suction. With this style of carburetor, it's always better to lift the jet tube into the throat towards the centre, rather than expecting good airflow at the intake wall). 

When starting mine, I find it best to just wet the piston at closed exhaust and use a syringe to add one drop, or perhaps two into the venturi. That should be plenty. Generous priming in the usual way will have you working on a false much lower compression setting that won't keep running. Go wit ha 6x3 propeller, which ought to bring RPM up to adequate speed for reliable operation. I run mine with equal parts ether kero castor oil plus .8% ignition improver. Tried same mix with mineral oil and it is less happy, but OK as an "after flight" fuel to avoid gumming up in storage. You might up ether to 40%.


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## creast (Oct 9, 2019)

Maris,
Many thanks for passing on the hints, I really appreciate that.
Yes I did notice over priming did give some strange results and I will now revise my technique as suggested.
First I need to rebuild the engine and check all is sealed well and rework the carb.
It obviously can run so I am half way there!
Cheers
Rich


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## creast (Oct 9, 2019)

Update
Thanks to the advice supplied by Maris, I now can run off the bowl carburettor and starting is much easier once you find the sweet spot settings.
The screws and rear cap were sealed with a very small amount of Hylomar (non setting joint compound) and the fuel tube extended to the centre of the choke bore.
I will run her in for a bit just to ensure all is ok.


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## 777engman (Oct 11, 2019)

A video of it running would be nice and encouraging to others maybe
Cheers
Dean


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## creast (Oct 12, 2019)

Hi Dean,
I have posted video in the finished projects section as this now a completed project.
Rich


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## KenC (Feb 9, 2020)

How different peoples experiences are. I have just completed a Clan, the latest of the 40 different engine designs built so far of a total in excess of 50 engines. The idea was to see what I could achieve with my downsized workshop of Chinese mini-lathe and mini-mill. My Clan has a slight leak from the cylinder to case joint, the holes for the cylinder screws go right through into the case and are not sealed, and the piston seal is very soft, it will not hold at all at top dead centre. Yet its first run was within a minute or so of the first fuel in the tank, it starts easily both hot or cold, and it turns the KeilKraft 5x3 prop [recommended for the original Clan] at around 10,000rpm. So much for the theories as to why your engine was initially a problem! I did make sure that the carb bore was exact to drawing, but the pointy end of the needle has a much smaller diameter than on the plan and also a much shallower taper so as not to block the carb bore too much.  And by the way, I never prime the exhaust of the Clan, I just finger choke the carb a turn or two. My carb assembly was cobbled together in aluminium and the tank bowl was machined from the usual source, the toughened plastic of a cheap screw driver handle. Attached are a couple of pictures, please do not look at the con-rod of which I am thoroughly ashamed, it looke like a miniature drilled-out dog bone! Pictures do make things look worse than real life.
The first run with all the messing about finding setting can be seen here 
And an even more boring video showing some hot and cold starts is here
The wobbling about is not a loose engine, it is just a vibration/frame rate artifact!









Note that in the "parts" image, the brass tube is not used as a fuel jet, the jet is drilled into the aluminium of the carb body. The brass tube is just for fuel pick up.


Ken Croft in SW France


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## creast (Feb 9, 2020)

Nice one!
I particularly like your version of the fuel tank.
Cheers
Rich


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## KenC (Feb 9, 2020)

Thanks. I have used a similar tank setup on several of my engines.
Ken


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