KR> light sport vs. experimental

[Ron Butterfield]

On Mon, Jun 1, 2009 at 12:11 PM, LG McCaw  wrote:
 The only question I've never really had a satisfactory answer
for is - IF I receive and E-AB certificate with stated limits falling
within the LSA category, (making it sport eligible) and later re-prop or
restate the max RPM or whatever, is it possible to reestablish the
operating limits - the certificate never changes it's always E-AB.

The E-AB doesn't change, but the Sport Pilot eligibility does.  One of the
requirements for a plane to be eligible for a Sport Pilot to use is that it
"always has met" the requirements.

So, if you set, for example, a 2500 rpm limit in the operational limits to
meet the standards, then later changed the operational limits to 3300 rpm to
get more performance, which then put you outside the performance
limitations, even if you change the operational limits back, that aircraft
can never again be eligible for Sport Pilot use.

-- 
Regards,
RonB

KR> I Need Some Advice From Flying KR'ers

[Ron Butterfield]

On Mon, Jun 1, 2009 at 2:09 AM, Mark Langford  wrote:

> But what I was fishing for is how those same questions are answered with
> respect to LSA,
> since that seems to be important to him.
>

There are many different flavors of LSA compared to Experimental-Amateur
Built.

Experimental is 51% or greater amateur built.  The "builder of record" can
get the repairman's certificate for that aircraft and do the annuals.  Any
owner can do any work on the aircraft, but only the holder of the
repairman's certificate can do the annuals.

LSA as a class includes a wide variety of completeness levels, from plans
built on up through fully completed aircraft.  It is only for these more
fully completed aircraft that there are special LSA repairman's
certificates.

In the KR/LSA subgroup, these would only be plans built, so the aircraft
would be licensed as Experimental-Amateur Built.  During testing, the
aircraft needs to be shown that it meets the performance qualifications
(limitations) of the LSA class (<=138 mph maximum speed, <51 mph stall speed
at gross weight and most critical c.o.g.).

At the moment, there are no proven KR variants that meet all those
requirements, so a KR/LSA is uncharted territory.  Since even Vans had to do
some tweaking/modification to their LSA candidate, it would probably be a
good idea to have someone with a private pilot's license do the testing.

If you want to build your plane and do the initial test flying as a Light
Sport pilot, you would probably be better off with a proven LSA plane
combination.

-- 
Regards,
RonB

KR> KR1 Plans specified width?

[Ron Butterfield]

Outside, top, widest point: 23"
Firewall, top: 18"

On Wed, May 27, 2009 at 10:51 PM, dustin Reves  wrote:

>
> What is the standard width of the KR-1?
>


-- 
Regards,
RonB

KR> KR-1 Plans Available ? Where ? How Much? other Terms ?

[Ron Butterfield]

The KR-1 plans are available from Rand Robinson.

They are $65.

Delivery runs from 3-8 weeks, depending on a variety of factors.

The plans are as complete and accurate as they have ever been.  They are
more complete and accurate than the original versions, as they come with
many revisions that have been incorporated over the years.

They are not, and probably never will be, as complete as the later 2 and 2S
plans, hence the difference in price.

On Tue, May 26, 2009 at 9:55 AM, Scott Perkins <2sc...@bellsouth.net> wrote:

> The question I have not seen answered is whether the KR-1 plans
> are available from the RAND company and if so how much and how long
> does it take and what kind of condition are they in.  IE such as
> complete, hi quality, accurate etc.
> Scott
>
>  



-- 
Regards,
RonB

KR> OT: Bit and brace?

[Ron Butterfield]

Lehman's Hardware in Kidron, Ohio has all kinds of non-power tools and
appliances.

http://www.lehmans.com/shopping/product/detailmain.jsp?itemID=6072=PRODUCT=1=brace
or
http://tinyurl.com/2gejfx

I still have the one from my dad in my toolbox. It's probably older than I am.

On 6/2/07, David Lininger  wrote:
> Anyone have a good source for an old-fashioned bit and brace? Dad had
> one years ago, but when they moved to the retirement home he sold a lot
> of his stuff, and I think that must have gone then.
-- 
Regards,
RonB

KR> Spruce vs Douglas Fir

[Ron Butterfield]

On 3/15/07, Darren Crompton  wrote:
> I am ready to order my timber and being on a very tight budget, I am
> seriously considering douglas fir as an alternative to spruce.

On http://krnet.org/ there is a link to the old paper KR newsletters,
downloadable in pdf. Many years ago a gentleman documented just such a
substitution, along with a test jig to make sure your wood matched
your calculations.



-- 
Regards,
RonB

KR> Aircraft modeling software

[Ron Butterfield]

I'm not sure how many of you engineer types are already aware of this, but...

We use Matlab (a computer mathematical analysis program) at work for
some of the products we sell, and I am a little bit familiar with it
due to having to provide support for these products. Because I am the
technical contact for our company with regards to Matlab I receive
their newsletters. These newsletters often have interesting bits of
news in them related to aerospace.

A few months ago there was an article about the design, construction,
and testing of a new civilian tilt-rotor aircraft targeted at the
offshore oil platform market.

This month's article concerns a new toolbox they offer that is
specifically for "flight vehicle design", specifically the flight
characteristics of a new light airplane. The article also links to a
published US Air Force data compendium tool.

http://www.mathworks.com/company/newsletters/digest/2007/jan/flightsim.html?s_cid=MLD0107na2TA2_v1=42005|1-E28H5
http://www.va.afrl.af.mil/org/VAC/VACA/vaca_index.html

This is all well over my head, but I think at least a few of you guys
here are working at this level, and I am offering it for your interest
if you are not already aware of it.

If nobody is interested in this, I won't hear any more about it and
won't bother sending any more updates on this topic.

-- 
Regards,
RonB

KR> 45 degrees VS. lengthwise

[Ron Butterfield]

On 1/3/07, bdazzca...@aol.com  wrote:
>
>  I was just curious what would happen if you were to fiberglass a foam
> fuselage lengthwise instead of 45?

If you use regular bi-directional weave cloth, run at 45 degrees to
whatever, both length and width stresses have to cross every fiber.
When the cloth is laid "normal", however, length and width stresses
only have to cross half the fibers.

Whether this is a problem in any given location depends on the
stresses involved; sometimes a light cloth is used more as a cover
than as a strength member.

-- 
Regards,
RonB

KR> Solid wings

[Ron Butterfield]

On 9/20/06, Allen Wiesner  wrote:
> Well, how about L/R wing panels joined at the centerline and with the
> dihedral built into the joint?

The problem with that is, as the center section is reduced, the outer
sections have to be made larger to provide the same wing area.

For example, on the KR2S:
wing center section 30 sf
outer wings 52 sf
63% of plane's weight supported on waf's

change center section to 36" span (round numbers to match fuselage)
wing center section 12 sf
outer wings 70 sf
85% of plane's weight now supported on waf's

This doesn't mean that it _can't_ be done, just that there are now
larger forces on the WAF's and the wood they attach to, and you must
re-do all the engineering and calculations to make sure things will
still work.

A possible exception would be to put the KR2-S outer wings on the
reduced center section of a KR-1.  This would give you very close to
the original wing area of the KR-1, and less stress on the WAF's due
to the lower gross weight.

-- 
Regards,
RonB

Re: Réf. : Re: KR> Delrin versus Nylon

[Ron Butterfield]

> Can you tell us some more about this material, what type of plastic,
> density, where do you get it and what cost compared to other plastics.

www.mcmaster.com has a huge variety of supplies and so is good for comparison.

You will often find items less expensive elsewhere, but their customer
service is hard to beat.

They have acetal (generic name) and Delrin, as well as Nylon and
lubricant-filled variants of each.

For comparison, 12"x12"x1/2" pieces of each:
Nylon (white) $29
MDS-filled Nylon (black)$33
acetal (black)$37
Delrin (black)$39
oil-filled Nylon (green)   $40
PTFE-filled Delrin (black)  $183

The tensile strength of Nylon makes the swarf into basically
monofilament, which makes it a real pain.


-- 
Regards,
RonB

KR> Brake suggestions?

[Ron Butterfield]

On 7/28/06, D F Lively  wrote:
> I am inthe process of installing bthe Great Plains system and their calipers 
> > have a piston on one side but pads on both.

This is very common, both in autos and motorcycles. You just have to
make sure the slider mechanism works freely, or that will cause
problems. Higher-end systems more often use pistons on both sides of
the disk.

> The creativity comes into play with the toe prkes.

Sorry, but I don't have a clue what those are ;-)

-- 
Regards,
RonB

KR> Re> Joe Flechtner's Anchorage to Oshkosh Trip

[Ron Butterfield]

On 7/26/06, Rick Human  wrote:
> I believe the articles you are referring to describe Fred Keller's
> experiences rather than Joe Flechtner's - Fred's adventures were written up
> in Sport Aviation and can be found on Don Reid's website.

You mean this one?
http://aerofoilengineering.com/KR/sportaviation/Kr74-1.HTM


-- 
Regards,
RonB

KR> 18% airfoil?

[Ron Butterfield]

At 10:41 AM 5/9/06, you wrote:
>I want to hot wire the 18% tapering to 15% but only four feet at a time.
>how do i come up with the middle airfoil?

An airfoil modeling program will help you do this. Profili is one 
written by a guy in Italy. Cost is 15 Euro.
www.profili2.com/eng/

If you enter the root and tip airfoil, and the distance from root, it 
can give you accurate templates for any position in between.



Regards,
RonB 

KR> CAD Software

[Ron Butterfield]

At 10:50 PM 5/1/06, you wrote:
>KR Netters (especially you CAD guys):
>
>This question is a two-parter: 1) What CAD software do you use and, 2) What
>would you recommend for a new CAD user / KR builder?

I've used TurboCAD as a hobbyist since version 1.2, and still can't 
get my head around the (newer) 3D part of it. As a beginner, it (or 
any other full-featured CAD program) is _not_ intuitive. For 2D, 
there was a version of V4 that was made available free as "TurboCAD 
Learning Edition". It is no longer available from IMSI, but there are 
still a few copies squirrelled away on various persons web 
sites.  Also, copies of newer versions are available cheap on ebay.

Another CAD program that is simple to use is DeltaCAD, billed as 
"World's easiest CAD Program" for $40:
http://www.deltacad.com/  There is a free time-limited demo that you 
can download to try out.



Regards,
RonB 

KR> LSA KR

[Ron Butterfield]

At 07:30 AM 5/2/06, you wrote:
>Hello all,
>
>Is anyone out there in KR land considering (or now building) a KR2 
>that would meet the qualifications for LSA certification?  I made a 
>search of the archives but there didn't seem to be a lot there as 
>far as LSA and KRs go.


After today's spate of LSA discussion, I put together a quick 
spreadsheet to calculate various performance parameters based on the 
discussion and formulae on this page:
http://zenithair.com/kit-data/ht-86-8.html

The straight Excel version is at:
http://home.mebtel.net/~rbutterfield/KR/Stall_speed_&_performance_calculator.xls

If you (or your isp) have problems with spreadsheets, the same file 
compressed with WinZip is at:
http://home.mebtel.net/~rbutterfield/KR/sspc.zip

I have entered CLmax from the stated sources for the two wings under 
discussion, but you can change that for other wings if desired.

Constructive criticism welcome.

And remember, it's worth what you paid for it (or maybe less ;-) )

I have NOT personally confirmed ANY of the data or formula in the 
spreadsheet, so use it at your own risk.


Top speed can be easily artificially limited by placarding a reduced 
max continuous rpm.

Stall speed is the hard part. LSA requires the maximum stall speed to 
occur at gross, without the use of "lift enhancing devices", ie 
flaps. Wing area and weight play a big part, but Cl even more so. 
Good hard data seems a bit hard to come by, especially at the lower 
Reynolds numbers a KR flies at near stall.

An interesting page of airfoil information is here:
http://www.oriontechnologies.net/Documents/Airfoil.htm

I personally have settled (for now, anyway) on a KR1 with 72 sf of 
23015 tapered to 23012. With an estimated Cl of 1.6, that gives me a 
stall of 50.4 at a gross of 750. The spars and attachment of the KR2 
are the same section, just longer, so it should be well within 
limitations without re-engineering.

For a KR2S and the new airfoil, the numbers get so far out of hand 
that the spars and attach fittings would need to be completely 
re-engineered. At a gross of 980, with Cl of 1.28, you need 111 sf to 
get a stall of 52.



Regards,
RonB

"expert riders use expert judgement to avoid using expert skills"
Phill Ross 

KR> LSA KR

[Ron Butterfield]

Sorry, didn't mean that last post to go to the list :-(


Regards,
RonB 

KR> LSA KR

[Ron Butterfield]

At 03:56 PM 5/2/06, VIRGIL N SALISBURY wrote:
> How about the KR-1b, Virg

Ran the numbers, 45hp stock 1600, 800lb, 91sf,
Airfoil is funny; center is RAF48 (CL 1.42), outer wings start as 
GAW(2) (CL 2.04) tapering to GAW(1) at tip (CL 1.8). Rough average CL of 1.76
Stall 44Top speed 130

Specs from Nov 79 newsletter:
Length  12'10"
Span27'
Empty   484
Gross   800
Engine  VW1834
Cruise  125@3200rpm
Stall   38 power off
Stall   45 w/spoilers
Glide   21.12:1

Maybe not good enough to qualify as a "real" motorglider, but perfect for LSA.



Regards,
RonB 

KR> alternative woods (doug fir, etc.)

[Ron Butterfield]

Remeber the newsletters? Used to come in the mail, printed on paper?

Back in March 1977, issue #21, page 2 had a short article on a 
builder using douglas fir on his KR, and how he tested and documented 
the substitution. The recommendation was to use 19/32" instead of the 
full 5/8". This gave parts slightly stronger than sitka spruce, and 
only slightly heavier.

A very large (for dialup, anyway) FAA document talks about wood 
specifications for airplane use. Reading and understanding this can 
help you make more informed choices regarding wood substitution.
http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/99c827db9baac81b86256b4500596c4e/$FILE/Chapter%2001.pdf
or
http://tinyurl.com/6m3aj

One main specification is grain slope (no greater than 15:1).

Most lumberyard wood is flat sawn (cross grain more or less parallel 
to flat side of board). Not a problem for us with stringers, as we 
can rip the strips and then turn them 90 degrees. 1x6 fir in the 
lumberyard is about 1.5x the price of 5/8x5/8 spruce at Aircraft 
Spruce. If you can get two out of a board you'll come out ahead ;-)

More work, less money. Your choice. But please, make an informed decision.



Regards,
RonB 

KR> alternative woods (doug fir, etc.)

[Ron Butterfield]

At 11:06 PM 3/27/06, D F Lively wrote:

>Carefull selection is required here and probably only premium clear 
>grade is all that should be used.

Definitely. However, if you are willing to put up with the waste and 
extra work, you can get a significant amount of premium wood from 
selected pieces of non-premium stock.

>The grain is the way is because it is
>slab cut so only the board cut from the center of the log will have 
>grain oriented  correctly.  To undstand how 1/4 sawn is cut look at the
>end of a log and envision the center of  wide direction of the board 
>being cut passes thru the center of  the log.  You can see that this will
>lower the yield of the log greatly , adding to the cost.

For the few "boards" in a KR, this is very much true. For a large 
portion of the wood in a KR, however, we need "square strips". If you 
cut a flat sawn board into strips, and turn them 90 degrees, viola! 
you now have quarter sawn strips. For a rough example, please see the 
following illustration:
http://home.mebtel.net/~rbutterfield/KR/quarter-sawn-from-plain.gif

Straight is still very much necessary, any knots must be cut out and 
discarded, and you must carefully choose the boards you are going to 
use to get close grain. You want at least 10 rings per inch looking 
at the end of the board; more is better. I have seen old-growth fir 
with over 100 rings showing at the end of the board (4").

>If you go into your average "Big Box" lumber souce and ask for 1/4 
>sawn you will
>most likely be met with a "Dumb Stare",

I thought that was a patented feature of those stores?  ;-)



Regards,
RonB 

KR> Retro-fitting Wing Tanks

[Ron Butterfield]

At 12:34 AM 3/10/06, D F Lively wrote:

>I am taking over a  KR2 project ...
>I intend to do all that I can to get it under sport-plane limits ...

Keep in mind that LSA requires the 52 mph max stall speed clean, and 
at gross weight. This means that you can _have_ flaps, but you cannot 
use them to arrive at your stall speed limitation.

For stall speed calculations, you need weight (gross in the case of 
Light Sport), wing area, and coefficient of lift.

For anyone playing with this idea, there is some good information here:
http://zenithair.com/kit-data/ht-86-8.html
Down near the bottom of the page are formula for estimating speed and 
stall. You need CLmax for the stall estimate; according to
http://www.krnet.org/as504x/design.html
the CLmax for the AS5045/8 wings is 1.28 clean.


According to http://fly.hiwaay.net/~langford/kraf48.html the RAF48 
has a CLMax of 1.42 without flaps at 18 degree AOA, so for this 
purpose it might be more suitable.

Playing with this info, it looks like a 700 pound gross, with 78 sf 
wing area, and the RAF48, would give you a stall of 50 mph. Another 
way to look at it, with the RAF48, you can have a maximum wing 
loading of 9.468 lb/sf. With the AS5045/8, you need a max of 8.873 lb/sf.

Top speed is a lot easier to do during the test phase; just decrease 
the maximum continuous rpm limitation to give you the desired top 
speed (138 mph).

Bear in mind that all the above is just desktop theorizing based on 
the published limitations of the Sport Pilot rule.

Or, as the British say, wanking ;-)



Regards,
RonB 

KR> Performance Calculator spreadsheet

[Ron Butterfield]

After today's spate of LSA discussion, I put together a quick 
spreadsheet to calculate various performance parameters based on the 
discussion and formulae on this page:
http://zenithair.com/kit-data/ht-86-8.html

The straight Excel version is at:
http://home.mebtel.net/~rbutterfield/KR/Stall_speed_&_performance_calculator.xls

If you (or your isp) have problems with spreadsheets, the same file 
compressed with WinZip is at:
http://home.mebtel.net/~rbutterfield/KR/sspc.zip

I have entered CLmax from the stated sources for the two wings under 
discussion, but you can change that for other wings if desired.

Constructive criticism welcome.

And remember, it's worth what you paid for it (or maybe less ;-) )

I have NOT personally confirmed ANY of the data or formula in the 
spreadsheet, so use it at your own risk.


Regards,
RonB

KR> CAD wing template

[Ron Butterfield]

At 10:04 PM 2/28/06, Steve Glover wrote:
>Not for the AS5048 - AS5046...

 From Mark's site:

The actual coordinates of all three airfoils are at this page:
http://www.krnet.org/as504x/as504x.html

What these do not give you are the spar locations, sizes, and tail 
feathers. Those are on the template:
http://www.krnet.org/as504x/templates.html



Regards,
RonB 

KR> cad file turtledeck

[Ron Butterfield]

At 07:50 AM 1/24/06, you wrote:
>Would anyone have a cad file of the front end of the aft turtledeck 
>profile to suit a dragonfly or rand robinson kr2s canopy,  any form 
>of drawing  file in autocad/turbocad/microstation etc, or even just 
>some measurements would do, I have the height and width from the 
>plans, just a radius that works for the corners would probably do.

Mark Lougheed has the files, but the links don't work:
http://www.fortunecity.com/marina/skipper/388/dflycanopysurvey/



Regards,
RonB 

KR> kr2 sport pilot

[Ron Butterfield]

At 06:04 PM 1/5/06, JAMES C FERRIS wrote:
>I have looked at this also, and on the list of performance of the flying
>KR-2's started by Orma about half of them have performance in the sport
>aircraft rules,

I suspect these numbers are either light, or with flaps, or both. LSA 
requires stall at gross, clean.

>however it would be better if we redesigned the aircraft
>to fit the rules and called it something else only useding the Ken Rand
>construction techniques. I am building a KR-2S but may lose my medical in
>the near future, that's why  I was looking to increase the wing area and
>span to improve the stall and climb speeds.

For anyone playing with this idea, there is some good information here:
http://zenithair.com/kit-data/ht-86-8.html
Down near the bottom of the page are formula for estimating speed and 
stall. You need CLmax for the stall estimate; according to
http://www.krnet.org/as504x/design.html
the CLmax for the AS5045/8 wings is 1.28 clean.

Keep in mind that LSA requires the 52 mph max stall speed clean, and 
at gross weight.

Playing with this info, it looks like you would need to be at KR1 max 
gross weight (or a bit less), and KR2S wing area (or a bit more), to 
even come close to LSA specifications. That is still do-able, though, 
if you are willing to have a single-place, VW powered, KR2S.



Regards,
RonB 

KR> Fiberglass laying

[Ron Butterfield]

At 10:13 AM 1/5/06, Serge VIDAL wrote:
>he showed me rolls of rigid plastic sheets (looking like old overhead
>projector slides). He said that's what his customers use when they want
>the cured surfaces to be smooth.
>
>That puzzles me. How come we don't do that? Is it because they fear
>trapped bubbles less than we do, or what?

This is done when you want an extremely smooth surface, and are not 
that concerned about weight. Rather than remove excess epoxy (like 
peel ply) the rigid plastic sheets bridge the humps of the weave and 
encourage the epoxy to completely fill them. It gives a very smooth 
surface, with very little extra work, but there are lighter things 
than epoxy to fill the weave with.



Regards,
RonB 

KR> Landing gear (mains)

[Ron Butterfield]

At 11:33 PM 12/14/05, Ron Smith wrote:
>Has anyone ever made fiberglass mains for the Kr with a similar 
>construction to the Grove gear?

Harold Woods used the fiberglass leaf springs from a Chevy Astro van. 
I'll forward his message to you off list.


Regards,
RonB 

KR> Nuts and bolts

[Ron Butterfield]

At 04:18 AM 12/7/05, Serge wrote:

>Obviously, to order that, I needed to identify the screw size correctly
>(remember, I live in Europe, so non-Metric things must be ordered from the
>US by mail order, and the order must be right first time, otherwise...I'm
>screwed!).

One resource for technical details for US screws (mostly not 
_Aircraft_ screws) is
http://www.mcmaster.com/

If you do a search for "screws", the first item to come up will be 
the selection list, with an astonishing array of types. Once you get 
down to a specific type, the catalog pages will usually have 
technical details for them.


For an example of mind-numbing detail, here is what comes up for a 
drilled fillister head machine screw, 8/32:
Part Number: 90350A265   $12.38 per Pack of 10
FED Specification   Fed. Spec. FF-S-92
MIL Specification   MIL 35275
Head Style  Drilled Fillister
Material Type   Stainless Steel
Finish  Plain
Stainless Steel Type18-8 Stainless Steel
MIL 35275 Dash #243
Drive Style Slotted
System of Measurement   Inch
Thread Size #8-32
Length  3/8"
Decimal Size.164"
Head Diameter   .270"
Head Height .156"
Hole Size   .048"
Thread Point Style  Machine
Specifications Met  Federal Specifications (FED) and 
Military Specifications (MIL)
Rockwell Hardness   B85-B95
Minimum Tensile Strength80,000 psi

along with a technical drawing.


Regards,
RonB 

KR> Primer

[Ron Butterfield]

At 02:09 PM 11/29/05, Ron Freiberger wrote:
>What ever happened to the pull-out-to -fill-push-in -to-squirt idea..?.
>Works well, easy to use, and simple.  Put one line to each side at the
>top, use a .016 diameter orifice.

The fuel lines don't _have_ to run into the cockpit to do this. It 
would be fairly simple to run a cable or small rod from the panel to 
the firewall, thus having the pushbutton on the panel but the fuel on 
the other side of the firewall.

Of course, it does increase parts count. ;-)

Think about mode of failure too.

If the primer doesn't squirt fuel when it's supposed to, what 
happens? The engine doesn't start and you sit there on the ground 
trying to figure out why.

On the other hand, if the primer squirts fuel when it's _not_ 
supposed to, what happens? In my opinion, there are a lot more bad 
possibilities with this option.

Just another opinion to add to the pile ;-)


Regards,
RonB 

KR> Covering material

[Ron Butterfield]

At 10:32 AM 10/16/05, Don wrote:
>I'm an automotive upholsterer by trade and if you don't mind my
>2 cents worth  my favorite material to use especially for canopy covers
>is a material called Odyssey Soft Touch manufactured by MarChem Coated
>Fabrics.Inc.. What it is is a light weight coated polyester that is waterproof
>and breathable and has a synthetic felt backing so it's not prone to chaffing
>plexi or paint and has a 5 year manufacturers guarantee.

I'm sure there are probably many places to get this, but here is one:
www.sailrite.com

If you download their pdf catalog, it is on page 72. $18.50/yd (5' wide)


Regards,
RonB 

KR> Covering material

[Ron Butterfield]

At 05:15 PM 10/18/05, Don wrote:
>I don't know if Ron is An upholsterer /Canvass guy

I'm not. I've got a local friend who is also a self employed 
upholstere , however.

My personal feeling is that it would be better to order something 
like this from someone who actually uses it themselves. In this kind 
of work, there are all kinds of details that can cause something to 
work either well or poorly.

On the other hand, many of us would rather do something ourselves 
than pay for 20 hours of someone else's labor, which is why I posted 
the link to the material.


Regards,
RonB 

KR> Re: Xpndr cable (Do not archive)

[Ron Butterfield]

I have a stash of RG58AU (stranded center conductor, tinned wires) that is 
no longer needed. If you guys want some, I can cut off 12 feet and mail it 
to you for $2 just to cover postage.  Email me off list if interested.

Regards,
RonB 

KR> rivnut question

[Ron Butterfield]

At 10:26 AM 4/22/05, Mark L wrote:

>The project I just finished up (at work)  required several hundred knurled 
>rivnuts (which are less likely to spin), so we
>learned a lot about them in the fabrication process.  ...   The problem 
>with that is if you don't get it tight enough, the rivnut just spins, and 
>you can't tighten up the bolt.  If you squeeze it too tight, the threads 
>get scrunched up and distort, and the
>bolt binds and the rivnut spins.  You'd think after several hundred, you 
>could get the feel of it, or get it adjusted correctly, but it never 
>happened...

I'm really surprised at this, as it runs opposite to my experience over the 
last dozen or so years.

Here's the tool I've been 
using:  http://home.earthlink.net/~ronb_4/images/rivnut_tool.jpg
It is the Nutsert brand; notice the knurled base of the mandrel to keep the 
nutsert from spinning in the hole (this is a 4mm tool).
Here's a picture of the actual nutsert: 
http://home.earthlink.net/~ronb_4/images/rivnut.jpg  (this is a 5mm 
insert). I've been purchasing my replacements from McMaster too.

Here are some possibilities for our different experiences:
I've generally been using small-ish sizes (M3-M6)
I've also been using them in relatively thick materials (1/16" min)

There are recommendations for different size holes for different material 
thicknesses:
http://home.earthlink.net/~ronb_4/images/rivnut_sizes.jpg


Regards,
RonB 

KR> Canopy questions. Plastic lay ups

[Ron Butterfield]

At 07:12 PM 1/18/05, you wrote:
>I have been to the Two largest building supplies in Australia. and they do
>not know what 3 mil thick builders Plastic is. They all say It CAN NOT BE 3
>mil (mm) thick.

Ahh! The dreaded English/Metric wars strike again. ;-)

Over here (USA) plastic is commonly sold by it's thickness in thousandths 
of an inch. So, 4 mill plastic sheet here would be sold there as 100 
microns 3 mill would be 75 microns, etc.


Regards,
RonB 

KR> Project update

[Ron Butterfield]

At 03:42 PM 12/5/04, Ron Smith wrote:

>I have constructed the bottom of the fuselage to conform to the shape of 
>the AS5048 airfoil.

I would be really interested to see this. I played with the idea for a bit, 
but didn't like the way it looked (at least with what I came up with).


Regards,
RonB

KR> LSA rules per Part21

[Ron Butterfield]

Anyone can read the EAA's synopsis of the Sport Pilot rule (19 pages 
instead of >400) at the following link:
http://www.sportpilot.org/rule/sp_rule.pdf

(4) A maximum stalling speed or minimum steady flight speed without the use 
of lift-enhancing devices (VS1) of not more than 45 knots CAS at the 
aircraft's maximum certificated takeoff weight and most critical center of 
gravity.

The new Light Sport category seems to be specifically for more complete 
kits (>51%) and completed aircraft. I'm not sure if the consensus standard 
for this has been publicly released yet, but that doesn't apply to us anyway.

"It appears" that any plans-built experimental will need to be registered 
under the previously existing experimental category & rules, and that you 
would apply for the previously existing "experimental repairman's 
certificate" to allow the owner to perform maintenance & annual 
inspections. The new "light sport repairmans certificate" is specifically 
for the more complete kits & completed aircraft, which would not qualify 
for the previously existing experimental category.

"It appears" that any plans-built experimental would be eligible to be 
flown by a lights sport pilot if it meets all the criteria for a light 
sport aircraft. I have yet to see anything from the FAA or EAA to even 
slightly touch on how that eligibility can be confirmed. I suspect that 
plan-builders will be at the end of the list, as far as priorities go.


Regards,
RonB 

KR> GPSMAP 296 @ Discount prices (AC Spruce)

[Ron Butterfield]

At 08:53 PM 11/4/04, Brant Hollensbe wrote:
>
>  For the president of a dealership to go public and announce that
>he has turned another dealership in and why, is a very poor bussiness
>practice indeed.

Why did nobody notice the AOL.com address and wonder if this is a fake?

As usual, I get suspicious if a purported company email comes from some 
other domain.


Regards,
RonB 

KR> Mylar Gap Seals

[Ron Butterfield]

Mark Jones wrote:
>  If anyone else knows where we can buy this in
>lesser quantities or even in 4" wide rolls please speak up.

This is untried, and I don't know if the cost per person is advantageous or 
not, but in the interest of diseminating information, here goes:

McMaster-Carr has an ultra high molecular weight polyethylene tape 
(hereafter known as UHMW) available that might well work in this 
application. It is available in .0045", .0065", and .0115" thicknesses, of 
which .0015" is adhesive. This is a very tough, slippery material, and the 
adhesive appears to be durable. It is available in widths of 1/2", 3/4", 
1", 2", 3" and 6" (not 4", unfortunately).

http://www.mcmaster.com/nav/enter.asp?pagenum=3197

I've used it for a bearing surface here at work, where we have a very heavy 
sliding door; I put it on the guide rail and it doesn't show any wear or 
signs of coming off after 7 years.

Will this work on a plane? I don't know. One hassle is that it has adhesive 
all the way across, and some way will have to be devised to keep it from 
binding on the aileron. If the thinner size is used, it could possibly be 
doubled on the half that is not meant to be stuck (kind of like a sideways J).


Regards,
RonB 

KR> UK builders

[Ron Butterfield]

At 09:16 AM 10/22/04, you wrote:
>Hi All.
>'Twould seem that my thoughts on building the KR2S in the UK will not be
>coming to pass. This morning I had a communiqué from the PFA telling me
>that the machine as yet is NOT type approved in the UK.

You might want to try and find this guy:
http://home.hiwaay.net/~langford/katkinson/


Regards,
RonB 

KR> G limit

[Ron Butterfield]

At 04:12 AM 9/30/04, Gavin wrote:

>I disagree that lift loads are much larger farther from the fuselage on the
>new 504xx wing designs!
>Maybe someone can shed some light on this? the chord of the wing decreases
>as the wing tapers to the tip, therefore reducing the available lift as the
>wing tapers due to reduces area.

A paper on load distrubution and how to calculate (close but approximate) 
the mean aerodynamin chord for a tapered wing is at this link:
http://www.bd5.com/BedeDesign15.jpg

So, the slightly conservative calculation for bending load on the spar 
would be half the maximum G-load gross weight of the plane at a lever arm 
of the MAC distance.


Regards,
RonB

KR> of wings, stubs, and attachments

[Ron Butterfield]

As drawn, the KR has wing stubs coming straight out from the fuselage, then 
the dihedral is built in at the joint between the stub wings and the outer 
wings.

What would be the problems with moving the wing attach point in to the 
fuselage, then having straight wings all the way out?

The advantage would be simpler wing construction and slightly cleaner 
appearance.

The only things I can see as problems are greater stress on the wing attach 
fittings and if the construction process requires short wing sections.

But then, I know I don't know it all. That's why I ask ;-)


Regards,
Ron Butterfield 

KR> Ellison EFS2

[Ron Butterfield]

Dan wrote:
>You have to beg, borrow, or steal to get an EFS-2 now

There is one on Ebay right now, for $399. I know nothing else about it.

Here's the link:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem=1=2488752466=26437=WDVW

Beware line wrap. If the link is on more than one line, cut and paste into 
notepad or something and edit to be all one line, then paste into the 
address line of your browser.


Regards,
RonB 

KR> To cool or not too kool

[Ron Butterfield]

Orma wrote:
>It seems that some where in the past I read that temps are
>different at different places on the head.  Is under the plug the hottest
>spot?

Well, I wacked Google on this one
http://www.google.com/search?num=50=en==UTF-8=vw+%22head+temperature+probe%22+=Search
and came up with this one result, which didn't show what I wanted to show
http://www.greatplainsas.com/bf20032.html

According to them (and some others) the spark plug is not an accurate place 
for head temp measurements. When the Mexican Beetles went to fuel 
injection, VW added a boss to the heads to provide a known place from which 
to measure temperature; that's what I can't find the picture of at the 
moment. If I remember correctly, it was near the corner of the valve cover, 
about 1-1/2" toward the center of the engine.


Regards,
RonB 

KR> CC ing the heads-Buret

[Ron Butterfield]

At 07:15 PM 5/17/04, Orma wrote:
>Man !!! $100 to $150 is too rich for my budget.

How about these?

$15
http://www.vwalley.com/images/head_cc_kit.jpg

I know nothing. I am only a messenger.


Regards,
Ron Butterfield 

KR> Successful VW Conversion

[Ron Butterfield]

The basic idea is to take a stock flywheel, cut in down on a lathe to an 
appropriate diameter, and drill it with a bolt pattern. This becomes the 
flange for a hand-start engine.

Then, a spool is machined from aluminum, with a center section of about 
2-3/4" diameter, about 4" long overall, with a flange on each end (one with 
the bolt pattern of the prop, the other with the bolt pattern of the 
flange). There is a hole about 1-3/4" diameter through the middle, I am 
assuming for weight reduction.

Caveat: I have not seen this, nor flown behind one, nor built one. This is 
just the information I have been able to find. I have also read that if the 
machining, especially the bolt circles, is not done accurately, the 
resulting offset can create a horrendous vibration and possibly break 
cranks or cases.


Regards,
RonB 

KR>Source for aluminum "T" stock.

[Ron Butterfield]

At 07:51 PM 3/14/04, you wrote:
> Can anyone give me a source for the 1" "T" stock as mentioned in Dean R.
>Collette's stabilizer/elevator hinge article.
>(http://home.hiwaay.net/~langford/dean_hinge/)  I assume it is 1/8" 6061 
>material.

McMaster has something very close. www.mcmaster.com  Search for part number 
1668T14, which is 1/8" thick x 7/8" high x width unknown (not listed). From 
the illustration, I would guess it's about 2x wider than high. These items 
are not in the print catalog. They also have 1/16" & 3/16" thicknesses, but 
a limited selection of heights.


Regards,
RonB 

KR>Nyloseal fittings

[Ron Butterfield]

At 02:55 AM 3/19/04, you wrote:
>Also does anyone know what the difference is between 1/8 BSP (Churchill) 
>and 1/8 NPT (Eisenhower)?  Must be bugger all at this dimension!!

I can't help with the other questions, but this one I can (I work for a UK 
company in the States).

NPT is the US standard for pipe thread.

BSP is British Standard Pipe, and comes in two flavors, tapered & parallel 
(BSPP & BSPT).

A more detailed explanation can be found here:
http://www.mcmaster.com/asp/enter.asp?pagenum=3


Regards,
RonB

Mebane, NC