My Engine

StanFoster

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Treaze- Welcome to our group that requires mistakes being made to be a member of. If one hasn't made a mistake, then that person isn't doing a thing. I keep paying my dues so I can remain in this group. Stan
 

Countach

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I have been using Unibits from Harbor Freight for years now.Love them,can find them on sale for 7.99 for a 3 piece set.They also make a 2 piece set that gos up to 1-1/4 dia.Have drilled AL,4130&SS with them.Also their spring loaded center punch is nice to have.
 

kc0iv

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I have been using Unibits from Harbor Freight for years now.Love them,can find them on sale for 7.99 for a 3 piece set.They also make a 2 piece set that gos up to 1-1/4 dia.Have drilled AL,4130&SS with them.Also their spring loaded center punch is nice to have.
I have a set from Harbor Freight and found they were off in what size they drilled. Example - 1/2 inch was .4843375 inches. A 1/16 inch error.

Leon
(kc0iv)
 

Passin' Thru

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I have a set from Harbor Freight and found they were off in what size they drilled. Example - 1/2 inch was .4843375 inches. A 1/16 inch error.

Leon
(kc0iv)
Are you saying you measured it to the 7th decimal place?:eek:
If so, that is only 1/64 (.015625) error. :rolleyes:
 

treaze

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I wish somebody'd start a thread of neat tools! Scottessex, thanks for the site--I've bookmarked it.

I just now used my cool new 6" digital calipers from Harbor Freight to check both my Irwin Unibits--1/2" was 0.495" and 0.497". Leon, are your "unibits" Irwin? It could be that Harbor Freight's versions are some off brand and that's why yours are so off. I know from experience that you have to be careful with some of the stuff from H-F.
 

kc0iv

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Pete -
Are you saying you measured it to the 7th decimal place?
If so, that is only 1/64 (.015625) error.
1/64 error is quite a bit in some cases. In fact the reason I measured mine was because I drilled a 1/2" hole and tried to put a 1/2" bolt in it and it would not go in. Measure the bolt and it was a true 1/2". Then measured the bit and found the error. Each of the steps were under sized.

Looks like Terry found the same thing when he measured his HF bits.

Terry -
Leon, are your "unibits" Irwin? It could be that Harbor Freight's versions are some off brand and that's why yours are so off. I know from experience that you have to be careful with some of the stuff from H-F.
Mine are a set from Harbor Freight.

Leon
(kc0iv)
 

treaze

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My Engine

I finally finished my engine bearers! I won't rehash how frustrating this little sub-project has been, from various causes, but will just document the finished product and offer some thoughts and crude dwgs that I hope may be useful to others. Re the 10mm engine-attach hex-head bolts, I ended up ordering them from LEAF, and are the ones (#940-326) called out in the Rotax Parts List--they're marked 8.8 on the heads. I verified with LEAF that 8.8's are the correct ones. They're held in place temporarily with junk nuts. The AN6-22A's going thru the Barry mounts are torqued down to 30 ft-lbs (360 in-lbs), as called out on the Barry Controls site--I verified that torque with them as appropriate for any load. The positions and orientations of the mounts themselves were ok'ed by 3 separate tech reps at Barry Controls--they said other installations people have used may work, but not as effectively as intended and designed for, and may not last as long. It's unfortunate that where I've located the 10mm and AN4 bolts, there's only 1/16" clearance between the heads--if I had it to do over again, I'd try something slightly different, like offsetting the AN4's away somewhat without violating 2D edge distance guidelines too badly. I maxxed the clearance as much as possible by using thin AN960-416L washers under the AN4 bolt heads, I used Lowe's thin "wave" washers under the 10mm bolt heads, I drilled the heads of the 10mm bolts for safety wire so I wouldn't need lock washers, and I added otherwise superfluous AN970-6 fender washers on top of the Barry bushings. If I have to later, I can add more of those washers as spacers.

Now I'm eager to get on to a new phase of the engine install on this same thread--the fuel system, probably. I figured out, btw, that I might as well get all these systems figured out and in place as much as possible before actually forking over big bucks for the engine. That way I can minimize wasting warranty time ticking down on me. Besides, that's a huge cash outlay that I'd rather postpone as long as I can because medical bills are killing me (is that ironic, or what?!).
 

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Alan_Cheatham

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Nice Job!

One precaution for anyone installing Barry mounts.
Barry's are little tight going into the 3/4" hole so if a lubricant must be used it should not be soapy water which can lead to rust, and should not be a petroleum based lubricant as this can lead to rubber degradation.

.
 

bushflyer

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Hi Allen,

nice to know. What stuff do you use for this kind of application ?

Have a nice day
Guenter
 

treaze

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From what I understand, petroleum jelly does indeed do a number on rubber and latex. But these mounts are neoprene, not rubber. I lightly used petroleum jelly to ease these mounts into position.
 

Dirtydog

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treaze : Are you going to use any eng. supports V from the keel?
Thought I would ask.......:rolleyes:


Plans don't going in to detail on howto make stuff sometimes..
:tape:
 

treaze

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Dirtydog - Ralph's design didn't have them, so I didn't. If I had a 503, used Starbee's single tube for an engine support horizontal, and wasn't concerned with meeting UL weight, I would've added the down tubes.
 

Redbaron

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no downtubes here! bone stock taggart bee :)
hope your medical bills are nothing major, trez! :/


Dirtydog - Ralph's design didn't have them, so I didn't. If I had a 503, used Starbee's single tube for an engine support horizontal, and wasn't concerned with meeting UL weight, I would've added the down tubes.
 
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treaze

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Woe is me. Alan's petroleum jelly comment was nagging at me, so I emailed B-C and got this response:

"We recommend against using petroleum jelly to install neoprene mounts because the material is attacked by petroleum based substances. The material in contact with the petroleum jelly may swell and its fatigue life will be reduced. Depending on the severity of the environment in which the isolators are used it may not be an issue, but if it is an easy option to replace the mounts I would suggest doing so. We normally recommend that soapy water be used to lubricate rubber parts for installation. Sometimes even plain water is sufficient. There is also a commercially available lubricant called P-80 that is used by a lot of our customers."
 

Alan_Cheatham

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Treaze,

I only made my comment because I could see in one of your pictures what looked like petroleum jelly oozing out from one on the Berry's.

Since you have not had them assembled that long just pully the mounts out, clean them up and check out the rubber, if it doesn't look swelled or degraded then reuse them.

Here's another piece of information:
If you check the specs on these types of Berry mounts you will find that when 4 are used to take the thrust load of a propeller they are severly overloaded and this is why some other aircraft engine mounts make use of 6 or 8.

.
 

treaze

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Alan - I'm glad, actually, to be clued in on the petroleum thing, so I can fix my machine. So I do thank you. Hopefully, all posterity will learn this, too. But I'm not going to add another bunch of mounts like other installations might be using, because I haven't come across anything in this forum to indicate there's been a problem with the Gyrobee. Or have I missed it? Thanks.
 

Alan_Cheatham

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Treaze,

It was not my intention to suggest you add additional Berry's to your mount, keep it just as you have it, but I was just trying to convey some general information that some may not know about.

One of the major design goals of the Gyrobee was to be ultralight legal and on any ultralight design this may require things to be done not in the best but lightest way.

.
 

treaze

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Alan - I saw that petroleum jelly oozing out, too, and was thinking of cleaning it up, but never got around to it. If I had, maybe you never would've thought to comment about the subject and your Forum public would be mindlessly stuck with mounts rotting away. So in this case, sloppiness pays off! Keep 'em coming.

Okay, I'm easing into fuel systems! More unspoken mysteries. How come I don't see anything about mixture controls, like on "real" aircraft with "real" engines? I.e., full rich to start, and full lean to shut down the engine, and everything in between at various altitudes. And in that vein, I haven't come across anything about how to shut down the Rotax or start it up. Isn't that a fairly important ops subject to ignore? Not even in the Rotax manuals? Maybe I've missed it. So what procedures have people invented to make it all work--yanking the magneto wire? Shorting it to ground? Which wire? Pulling off the fuel line? Ha.
 

Alan_Cheatham

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Okay, I'm easing into fuel systems! More unspoken mysteries. How come I don't see anything about mixture controls, like on "real" aircraft with "real" engines? I.e., full rich to start, and full lean to shut down the engine, and everything in between at various altitudes. And in that vein, I haven't come across anything about how to shut down the Rotax or start it up. Isn't that a fairly important ops subject to ignore? Not even in the Rotax manuals? Maybe I've missed it. So what procedures have people invented to make it all work--yanking the magneto wire? Shorting it to ground? Which wire? Pulling off the fuel line? Ha.
All these thing have been covered many times in various threads but here's my take.

First, the carbs on the Rotax don't work the same as carbs on aviation engines and don't have cockpit adjustable mixture controls. There is an enricher which can be set up to for cold starts, some use it and others don't preferring to use a fuel primer. Having gone to the trouble of setting up and trying the enricher I would say don't, just use the primer.

To turn the engine off just turn the mag switches to OFF which on the Rotax actually shorts out an ignition module pin to ground. (note: the MZ engine is different)

I for one don't believe in running a two stroke engine dry for shutdown which is standard aviation practice for certified engines, but you may want to drain the carb bowls if storing the gyro for more than a few days.

If you live in a humid area you should take some precautions to keep dehumidified air in the engine during storage, there are some systems out that can be made or purchased for this.


One recommendation I have is to get the CPS (California Power Systems) catalog and read "The Proper Care and Feeding of the Rotax Motor" section, lots of good information there.

.
 
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