Nose Gear Screwup - Please advise

[rnbraud]

I would appreciate some advice.

 

I am working on the nose and while waiting for parts, I got a lil impatient and built and installed the NG-30's

before receiving my MKNG-6A.

 

The NG-30s are installed, the nose bottom is installed, the nose sides are installed, and the inside layups are complete.

 

Now, to my major disappointmnet, the MKNG-6A bolt won't go through the hole in the NG-30's.

 

Hmmm, so I re-read Chap 13 for the n'th time, and dammit,there it is on page 5, the end of the first paragraph:

 

After cure, open up the holes for the MKNG-6 to 5/16" I.D.

 

Dohhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh! My MKNG-6 hole is still 1/4".

 

So, I look inside and I can't see anyway to fit a drill and 5/16" drill bit in there.

 

I have a 90 degree attachment for both my drill and dremel.

 

For the Drill once you add the drill bit I won't be able to get it in there.

 

For the Dremel, it might fit, but they don't make 5/16" drill bits.

 

So, here are my options:

 

1) Cut the drill bit down to a knub, and see if it will fit with the 90 degree attachment.

2) Use the Dremel 90 degree attachment with a 5/16" cylinder HSS cutter. Followed up with a 5/16" grinding stone for clearance.

 

Any other ideas you guys might have??

[Lynn Erickson]

I would appreciate some advice.

 

I am working on the nose and while waiting for parts, I got a lil impatient and built and installed the NG-30's

before receiving my MKNG-6A.

 

The NG-30s are installed, the nose bottom is installed, the nose sides are installed, and the inside layups are complete.

 

Now, to my major disappointmnet, the MKNG-6A bolt won't go through the hole in the NG-30's.

 

Hmmm, so I re-read Chap 13 for the n'th time, and dammit,there it is on page 5, the end of the first paragraph:

 

After cure, open up the holes for the MKNG-6 to 5/16" I.D.

 

Dohhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh! My MKNG-6 hole is still 1/4".

 

So, I look inside and I can't see anyway to fit a drill and 5/16" drill bit in there.

 

I have a 90 degree attachment for both my drill and dremel.

 

For the Drill once you add the drill bit I won't be able to get it in there.

 

For the Dremel, it might fit, but they don't make 5/16" drill bits.

 

So, here are my options:

 

1) Cut the drill bit down to a knub, and see if it will fit with the 90 degree attachment.

2) Use the Dremel 90 degree attachment with a 5/16" cylinder HSS cutter. Followed up with a 5/16" grinding stone for clearance.

 

Any other ideas you guys might have??

get one of these you will need it all thru the project

http://www.aircraftspruce.com/catalog/topages/tightfittoolkit.php

[rnbraud]

Thanks Lynn,

 

That one looks way better than mine. Then again mine only cost $9 bucks at Harbor Freight.

 

It is Christmas time, so I think I will add it to my list.

 

Later.

[Cozy Girrrl]

Get a long aircraft drill bit, also an extension, don't be bashfull about making a hole in the side of the fuselage and then drilling through. You want the long bit because you want to align drill the two holes, oogering (technical term) them out off-axis with a short stubby drill on a 90 deg attachment will probably lead to a poor fit. Sloppy fits of the NG-6 will cause a lot of misery later on.

Regards, Chrissi

[Phil Kriley]

Get a long aircraft drill bit, also an extension, don't be bashfull about making a hole in the side of the fuselage and then drilling through. You want the long bit because you want to align drill the two holes, oogering (technical term) them out off-axis with a short stubby drill on a 90 deg attachment will probably lead to a poor fit. Sloppy fits of the NG-6 will cause a lot of misery later on.

Regards, Chrissi

That makes sense - but what do you think about that "tight fit" drill kit for other areas? Worth getting or not? Santa needs to know!

[Cozy Girrrl]

90 deg drills are handy when good planning fails

(lets just say we own one)

Just remember they are very difficult to get a true/aligned hole with.

Regards, Chrissi

[Tyson]

90 deg drills are handy when good planning fails

(lets just say we own one)

Just remember they are very difficult to get a true/aligned hole with.

Regards, Chrissi

I don't know if it would be possible to build such a jig that would fit in tight quarters, but check out the picture of this jig that is used to drill holes through the KR-2 wing spar (to align the bolts in the wing attach fittings):

http://www.kr-2s.com/images/pass_600.jpg

 

A few step process would be involved to open the holes but I think it is doable if so inclined.

[Cozy Girrrl]

Unless the farside part of the jig is somehow pre-aligned by a pin in a pilot hole or something it is redundant and does not do anything; by the time the drill reaches it the dirty deed is already done to the parts than matter.

For a jig to work it has to first clamp in some repeatable way to the parts that need to be drilled, then it needs to have bushings to center AND ALIGN the drill to the parts that are fixtured.

Hope that helps?

 

...Chrissi

[Tyson]

Unless the farside part of the jig is somehow pre-aligned by a pin in a pilot hole or something it is redundant and does not do anything; by the time the drill reaches it the dirty deed is already done to the parts than matter.

For a jig to work it has to first clamp in some repeatable way to the parts that need to be drilled, then it needs to have bushings to center AND ALIGN the drill to the parts that are fixtured.

Hope that helps?

 

...Chrissi

This may have come out clear as mud, but here it goes:

 

With the c-jig, you could do this by making the initial drill-through hole (in the jig) 1/4". Then remove the center of the jig (with sufficient depth to lap over the NG30 outer surfaces, about 3.75" or so). Then open up one end of the c-jig to 5/16". Place the jig over the NG30s. Place a 1/4 bolt through the jig and either NG30 (i.e. the side that you are not currently opening up).

 

At this point, the 5/16" opening of the jig should be centered over the 1/4" holes in your NG30s (assuming! that your current 1/4" holes are aligned).

 

After drilling out the first side, remove the jig and open the other end of the "C" to 5/16". Replace the jig over the NG30s, bolt the first NG30 to the jig with a 5/16" bolt, then open up the second NG30 to 5/16".

 

The idea here is to create a jig to open up the 1/4" holes to 5/16" without making out-of-round holes while keeping things as square as they currently are. It self-aligns/centers using the current holes.

[Larry Wiechman]

rnbraud,

You need a short, stub length .3125 diameter drill bit with a .25 pilot. If you havn't solved this problem yet, send me a PM with your contact info. I'll grind one up and send it to you.

 

Larry

[www.kr-2s.com]

Unless the farside part of the jig is somehow pre-aligned by a pin in a pilot hole or something it is redundant and does not do anything; by the time the drill reaches it the dirty deed is already done to the parts than matter.

For a jig to work it has to first clamp in some repeatable way to the parts that need to be drilled, then it needs to have bushings to center AND ALIGN the drill to the parts that are fixtured.

Hope that helps?

 

...Chrissi

 

 

Hi.

I am the guy who built the jig in question. You are absolutely right about pre-aligning the hole before drilling through. What the photo does not show is that 4130N steel WAFs (wing attachment fittings) are used to join the inner and outer spars. These WAFs have holes drilled and it is these holes that the jig aligns on either side of the spar. Whilst the WAFs are not 100% complete, you may get an idea of what I am talking about here http://www.kr-2s.com/wafs.html

 

To align the jig, you pass a same size drill bit (3/16") through the opposite side and poke it into a WAF drill hole. Hold another WAF on the opposite side of the spar and start drilling through the jig and matching WAF hole.

 

Unfortunately, I have had to place a ban on people linking directly to pictures on my site but you can see the jig at the bottom of this page. http://www.kr-2s.com/spar.html

 

Happy building.