catboater

My Feedback: (51)

I've got a new pretty cowl for my Cub all ready to go but I don't know how to mark the mounting holes to match the already blind nutted holes on the fuse. Anyone know a good technique for this or should I just drill new ones?

MX240

My Feedback: (4)

Gee, I am the first post....well here is how I have done it.
I get me a sheet of stiff construction paper.
Cut in half inch wide strips...a foot long
Cut a "point" on one end
Without your cowl on your plane tape the strips of paper on side of airplane with "pointer" at EACH hole CENTER
Fold back paper strips
Put your new cowl on and fold stips back over new cowl
WA'LA paper pointers show where to drill hole

Will watch for a better solution

David Cutler

I do a similar thing with an inch wide piece of balsa or ply sheeting with a point on one end, or a hole near one end. Position the point (or hole) over a hole, tape into place, then slide the cowl into place under the pointer and mark where the point (or hole) appears on the cowl.

-David C.

DGrant

My Feedback: (4)

Just use a piece of paper, thin is fine, about what would be equivalent to typing paper. Tape the paper on the side of the plane...with enough covering the existing holes in the fusalage(the ones with the blind nuts). Leave enough that you just pull it back while the tape is still holding onto it, and holding it in place.

Then you can mark the existing holes that are in the fusalage right onto the paper. Shading the area with the side of a pencil leaves a very decent impression, and no doubt where the holes are. Dont let the tape let loose on the fusalage, or let the paper shift, but, just pull it back after the holes are marked in the paper. Allowing access to install your cowling and line it up where you want it, without even having to worry about where the holes in the fuselage are. Take some tape, and tape the cowling to the fusalage(top and bottom if you can), and make sure its secure where you want it.

Then...simply flop your paper that you have already marked right down where it was, this time with the cowling in place(hopefully nothing moved), and walla....transfer the marks that are on the paper to the cowling, and there you have it...the marks you made in the paper obviously will line up with the holes in the fusalage...therefore, the marks on the cowling will obviously line up with the holes also.

Really very easy to do.....good luck.... just paper, tape, and pencil...thats all you need for this one.

Tall Paul

Use transparent stuff...
Or a short piece of Scotchâ„¢ tape, doubled over for some of its length so it sticks only at the rear end.. taped to the fuselage behind where the cowl will be.
Mark the holes in the tape.... slide on the cowl under the tape, drill to suit.

CafeenMan

I was going to say just use some JB Weld to hold the cowl on, but the ideas already posted might be better.

catboater

My Feedback: (51)

Hey guys, these are all great ideas. It's just like cutting the engine cut outs. I don't know why I didn't think of that myself but these are a new twist that'll probably work better. Thanks!

Tall Paul

This is such a common situation in full-scale, any competent flight-line mechanic will have several tools to do this to put new sheeting when old sheeting been removed, where the holes must be duplicated.
Usually the tool has a piece with the proper sized bit for the hole at the end of long arm.
The bit is placed in the hole.
There's another arm that places a bushing of the proper size over the prospective hole on the other side of the sheet aluminum.
Drill thru, good match.
The arm lengths will vary to suit.
The bit and bushing are assembled to the arms at the same time, to insure the fit.
Almost worth the effort to build for a model, if the problem is common.

Wayne Miller

Hi,

I wasn't going to respond since so many other good ideas have already been posted. But here goes:

What I do is to block the aircraft so it is stationary and won't move. I then pur my laser pointer (for presentations) in a clamp and shine it on the screw hole in the fuselage. Then slide on the cowling, where the laser spot is, is where the hole should be - mark it with a fine felt tip pen.

Do the same for all other holes.

Hope this helps.

Best regards,

Wayne Miller

RichLockyer

Reach inside the tank area and put something through the blind nut (like a sharpened screw) to mark the inside of the new cowl?

David Cutler

Yep! You can use the strip-of-wood-with-a-point-on-the-end to find where to cut holes for cylinder heads mufflers etc too!

-David C.

catboater

My Feedback: (51)

That laser pointer is a very cool idea. If I only owned one already.
My hands are way too big to get in the tank compartment. You should hear the cussing when I'm trying to hook up a fueler in there!

RichLockyer

Build bigger planes

catboater

My Feedback: (51)

Bigger planes?[X(]
Another great idea! Man, I really love RCU!

Richard L.

My Feedback: (24)

These ideas are really slick. I just used the "paper pointer" method this morning to install a new canopy, and it worked like a charm:

hookedonrc

You know, this is a great site. I am just about ready to install a canopy on a kit I am finishing. I would have never thought of any of these ideas. I will incorporate this into my kit building tips. Thanks All!

P-51B

My Feedback: (5)

I use this method, but I use plain old masking tape. I place the tape in position, mark the hole on it, hold the tape back out of the way (still stuck to the fuse of course), place the cowl in position, place the tape back in position. Now you can cut the tape at the cowl line, remove the cowl with marked tape still in position and cut your holes without fear of drilling into any threads accidentally.