If you are going to use the Nordlocks, do not use any goop on the threads. Get them as clean as you can.

I don't have the NerdLocks yet but from the McMaster Carr drawing, I think I understand how they work.

Why do you think that it's important not get goo on the threads?

Because it will effect the torque/preload relationship. It should be as clean as possible so the torque goes into preload, not friction. If you need some Nordlocks, PM me.

I have a batch coming but thanks anyway

The kitchen sink!

I've got to say, when I torqued down the bolts with the NordLocks they certainly had a solid, positive feel to them. The ones I used on the standoffs did not loosen up at all after many flights.

I am flying tomorrow and will give them their first real-world test (at least for me) on the header bolts.

Hi Guys

As far as the surface on the engine being perfect it is anything but what I did was flat file the flange, it only took a few stokes and it was looking good but put a rag or something in the exaust port so filings dont get in there.

Wish I had time to fly that much only once a week for me the field is 50 miles from my house.

Gordon
In Sunny Seattle for a day

My bolts had quite a bit of oily gunk on them. I cleaned the bolt holes and bolts with a pipe cleaner brush and paint thinner. A cleaner thread should lock better with the red silicone.

The exhaust port on my engine was also a bit rough. Header flange too. I just block sanded with 400-600 to a smooth finish. Should work fine but we'll see

Hi

What we use here in the shop to clean threads of silicone and loctite is a tap works great.

Gordon

I got in 4 fairly long flights today, totalling approximately 50 minutes running time.

After the installation of the NordLock washers, it leaked about 4-5 drops of liquid exhaust residue around the header, but there was no residue on the firewall or inside the cowl. If it were to stay like that, I would consider it a totally acceptable situation. Previously there was enough leakage to make me think there might have been a small loss of horsepower, and it was creating a bit of a mess inside the cowl.

I would try a dab of the RTV, and do not tighten fully. In fact, lay some .005-.010 fishing line to space it correctly. Believe it or not, that was the standard operating procedure at TRW to control bond line thickness in advanced composite space vehicle structures. Let it set overnight, then tighten with the Nordlocks. What some enterprising person should do is CNC a shallow groove around the port on the header and insert a controlled crush copper wire in the groove.

Bob,

How tightly did the bolts hold?

I received the NerdLocks and Ultra Copper Permatex this afternoon.

After cleaning bolts, holes, and making sure everything was flat, I re-assembled with a thin ally gasket I made from flashing. Gasket was Ultra Coppered in. Tightened the bolts to about 100 in-lbs (per Todd).

Permatex takes 24 hours to fully cure so I should be set for the weekend. Up to now, I couldn't get 3 flights without the header loosening. The evidence on my set-up was lots of oil residue on the bottom of the stab (there should be none if the header holds tight)

That should work well. The trick in making Nordlocks work, is to have a hard, controlled crush under the fastener. It works on maintaining preload, so on a soft squishy surface wont work.

Matt, as far as I can tell they don't appear to have backed out at all. However, I did not even touch them with a hex driver to test, nor do I want to disturb them in any way at this point. Just want to see how long and how well they hold up in their current state.

Same situation with the coupler. Leaked extremely little around the ES pipe — maybe 2 drops for the day, judging from the very minimal 'streamers' — which is totally acceptable to me, and none at all on the header end of the coupler.

Bob,

I added the Ultra Copper to the bolt threads. In glow stuff, that approach held exceptionally well without Nordlock washers under the heads.....easy to remove without heat.

In gasoline, I have the Nordlocks in place and permatex on the threads. We'll see how it holds. I cleaned all thereads very well with solvent to insure a better bite

Teflon coupler is much firmer than the turbo hose and I have always gotten "streamers" as you say. No big deal just annoying. Taking a look at the teflon coupler, there appeared to be some degradation inside. BUT taking a brush and some solvent to the inside of the tube, what appeared like degradation was nothing more than oil residue. It came right off. I used the same piece (still like new) and installed it with spring clamps this time. We'll see if that holds any better to a leak free result

One more thing....the carb tends to spit a considerable amount of fuel as evidenced by the blue discoloration on the foam carb insert I use in mine.

Yes I know. Thread chasing is common practice to remove hard bits and chips from threads. The problem in mine wasn't hard stuff in the threads...it was oily residue from the exhaust. A pipe cleaner brush dipped in solvent and then chased with a Qtip cleaned the residue great

Matt, do you have a link for the exact Teflon material you are using for your coupler?

I want to include the link in the "Cookbook" post so that the Teflon option is also available in a common location.

Just for the heck of it, the last couple of times I've flown I have used the electric starter for the first start of the day, without using the choke. Starts up fine after a couple of seconds, with subseqent hand starts the usual one- or two-flip affair. With the no-choke option available, it is obviously a viable option to use a simple carb stack (venturi) without having to use the choke plate, or looking for some ingenious way around it.

It's McMaster Carr item 5033K43; 7/8" ID X 1" OD (1/16" wall).

It fits the parts we require just about right....needs slight push over the button heads but that's all. Material should have a good spring clamp over it that produces good 360 degree contact for a decent seal. BUT as discussed before, one should not use worm-gear clamps or any type clamp that will distort the pipes underneath.

I've used a starter also before, for what's worth. I don't like them....they scratch the spinner finish. On the other hand, I am not thrilled with the baffle choke arrangement of the carb. I am working on a carb inlet solution around the baffle choke that will enable easier intake muffling.

Thanks, Matt.

I updated the Cookbook (post #877).

I also added the link for the spring clamp (part # 7329K15) which is the 15/16" wide-band spring hose clamp. If this is not correct, please advise.

Bob and all,

either this one or 5324K22 which is the type I am using. Just a wire loop. The flat band type requires a bunch more pressure to open and produces more pressure when closed. Either way is fine.

Here's the RECIPE that BOB and MATT have created (with bits of added info from few other sources) for the care and feeding of the SAP 180 with some additional inclusions to Bob's original post #877

1) [link=http://www.syssaaircraft.com/cart/pc/viewCategories.asp?idCategory=11]SAP-180HP engine[/link], 87-89 octane pump gas (10% ethanol), [link=http://www.syntheticoildistributor.com/amsoil_2cycle_oil.html]AMSoil Saber Pro[/link] 85:1 (after break-in with dino oil)

2) Another excellent synthetic oil you may use is BelRay MC-1 motorcycle oil mixeed 50:1. This oil may be used from initial runs to everyday

3) [link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXZ646&P=7]Macs tuned pipe header for OS 1.40RX[/link], available from Tower Hobbies. The mounting holes need drilled to M5 size and recessed to fit the bolt heads and washers

4) Per Hoffman, NordLock washers under the bolts hold the header secure. This is a standard McMaster Carr item(We have had some trouble securing the header on the exhaust long term and NordLocks are touted to help). Another approach to holding the header on is to use Locktite threadlocker (per Todd Syssa) on the bolt threads. Removal of the locked bolts requires heat up with a soldering iron first

5) [link=http://www.escomposites.com/petrol.htm]ES 30G or 40G tuned pipe[/link]from escomposites.com. We install a couple button head screws on the stem to keep the couplers on. Either 2-56 or 4-40 X 1/8" work fine; see item 8. The distance needed from the spark plug to the baffle inside the pipe is 27" minimum, measured in straight line. We are currently running our set-ups with a distance at 28". Matt has run to a distance of 30" with very little performance difference noted

6) [link=http://www.siliconehose.com/commerce/ccp11370-870id4-ply-silicone-saej20-compliantgl-c40-087.htm]Silicone turbo hose[/link] from siliconehose.com, 0.870'' ID, rated SAE J20 R1, for the coupler, and also Matt (MTK) has had great success with [link=http://www.mcmaster.com/#5033k43/=7gklvt]Teflon tube coupler[/link] material from McMaster-Carr. Use standard nylon zip ties to secure the silicone turbo hose, and [link=http://www.mcmaster.com/#spring-hose-clamps/=7gloj1]wide-band spring hose clamps[/link] (Part # 7329K15) for securing the Teflon tube. The wire spring clamp is also used successfully and is what Matt currently uses to hold the teflon coupler

7) Use a [link=http://www.rcuniverse.com/forum/m_9237216/anchors_9687199/mpage_31/key_/anchor/tm.htm#9687199]1-inch long piece of 0.875'' OD aluminum tube[/link] as a spacer between the header and the pipe to minimize direct exposure of the turbo hose to exhaust gases. If you use the teflon material as coupler, the aluminum spacer is not necessary and in fact may cause you grief because it will slide inside the teflon tube. The ally spacer is a great idea only for the silicone turbo hose to keep hot exhaust gas internal exposure to a minimum

8) Place [link=http://www.rcuniverse.com/forum/fb.asp?m=9694367]3 or 4 buttonhead screws[/link] near the end of the header and the ES pipe to prevent the hose from sliding off. A couple of zip ties on each end will secure it solidly.

9) The engine can be hard mounted, but for pattern you will probably want to use a [link=http://www.rcuniverse.com/forum/fb.asp?m=9393393]soft 'isolator' mount[/link], making your own as described in [link=http://www.rcuniverse.com/forum/m_6285026/tm.htm]this thread[/link] by MTK. I'm fairly certain that Merle Hyde would be happy to make a soft mount, using the stand-off bolt template supplied with the engine. The Hyde mount will cost about 200$ based on work Hyde has done with the ZDZ40cc mounts. The noise difference is substantial between hard mounting and soft mounting an engine....airframe and radio high freq vibration difference is also substantial

9a) Intake noise is considerable eventhough the intake is rear mounted. Matt uses a simple block of very open cell sponge from Home Depot to help reduce some of the intake noise. It's the type orf sponge material used for drywall sponging

10) [link=http://www.rcuniverse.com/forum/fb.asp?m=9607516]Nose ring[/link] and [link=http://www.rcuniverse.com/forum/fb.asp?m=9599410]Static nipple[/link] on the carb ambient pressure reference plate. Eliminates inconsistent engine runs caused by pressure changes inside the cowl.

11) [link=http://www.apcprop.com/ProductDetails.asp?ProductCode=LP15512W]APC 15.5x12W prop[/link] (break-in with something with less pitch). I have tried a bunch of props and there is something magical about this prop with this set-up. The standard APC 16x12 pattern is almost as good, and an acceptable substitue if you can't get the 15.5x12W, which I got from Gravesrc.com

12) We have also used successfully the 18.1x10 apc, 17x10 apc, and 17x12 apc. The 17x12 that Matt uses allows lower rpm than the 15.5x12 Bob uses, but works well in a 10 1/2 pound pattern plane for noise and constant speed. It is the lowest noise set-up we have tried. The point is they both work well depending on what you want out of the package. The 18.1x10 and 17x10 are lower load overall (noisier too) and are good choices for break in.

Matt has tried the 15.75x11 3 blade (courtesy of Dave Lockhart). Matt's engine worked well on this prop but Temptress less well with it. The 3 blade repitched to 10" had been tried before with the webra up front but it didn't work well then either.

13) Also recommended (to keep things light) is a [link=http://www.syssaaircraft.com/cart/pc/viewPrd.asp?idproduct=35&idcategory=11]Syssa (Tech-Aero) Ultra IBEC[/link] , which eliminates the need for a separate igntion battery and switch, saving about 5 ounces of weight (HUGE!), as well as optical kill switch, all controlled from the Tx.

14) Bob is also using a [link=http://www.tech-aero.net/plr5-i]Tech-Aero Designs switch/regulator[/link] for the Rx, with a Fromeco Li-Ion 2600 mah, but with the proliferation of LiFe batteries one could use one of these with no regulator. We like the Tech-Aero reg because it has a fail-on switch, so even with a LiFe I might use the Tech-Aero switch/reg for this feature alone.

15) Matt uses a single regulator and a single 1780 Lipo airborne battery. Point is one has several choices in regard to airborne battery set-up. Both Bob and Matt see similar current draw requirements per flight of about 200 mah per 15 minute flight

As we continue to develop the set-ups we will post findings here-in

Great update!

I had been meaning ask you about that 3-blade prop from Dave.

<span style="text-decoration: underline;"><u>Great job guys. </u></span>

I show you all the insight that you will need to be successful should you decide to tackle a soft mount. I leave nothing to guesswork

Tele, the link is good for getting another overview of the soft mount, but leaves out a lot of the in-between steps. Matt's thread pretty much describes each step from square one, and is also specific to gassers using standoff motor mounts.

Speaking of "insight", I ordered the [link=http://www.insightrc.com/Evo-orderpg1.html]Pentathlon Evo[/link] kit (insightrc.com) and the wood parts will be at my door in a couple of days, with the foam parts to follow a few days later.

Mark Hunt, who designs and sells the insightrc line of kits, told me that he has been following the SAP-180 thread with great interest, and went so far as to work out for me a special re-design of the nose to accommodate the SAP-180 using the 6.25" standoff standard and a soft mount 7/8" thick. Using my measurements and soft mount drill templates, and Syssa's engine dimension diagrams and standoff mounting templates, Mark used his CAD program to design in the left offset for the engine and 2.5 degrees of right thrust, with bolt holes for soft mount pre-drilled (laser cut, actually) in the firewall. Mark of course now has the cut files for the new SAP-specific firewall — which also required a small modification of the basic fuse frame for the back-set firewall — and therefore will be able to have one laser-cut for anyone with the intention of soft-mounting the SAP and using an ES pipe.

If that isn't enough, Mark also is providing the front and rear ply discs — again SAP-specific, with standoff and firewall mount holes already cut!! — for those who want to make their own soft mounts!

Furthermore, he has widened out the pipe tunnel formers a bit more to better accommodate the ES 30G pipe!!

Mine will the the first SAP-specific kit and so in a way it is something of a 'proof of concept' at this point. However, Mark clearly knows what he is doing and seemed to have all the information he needed to make an accurate adaptation for the SAP engine.

Of course, once I get the basic fuse framework together and make my next soft mount, I will be able to test-fit all the pieces together and will have a good idea how it's going to come out. There's no reason to believe at this point that it will be anything but perfect.