pat_willcox

I have several .40 size trainers that I want to convert from rubber bands to a dowel rod/ nylon bolts. I have been searching for previous postings with "How To" but am unable to refresh my memory. Our club is hosting a large scout troop "intro" day and I need a more user friendly set up.
Pat Willcox
[email protected]
www.jetero.com

Avaiojet

Pat,

I never converted a model, that had rubber bands, to a dowel mount after the model was completed.

Not difficult to do at all. You'll need a plywood former to except the dowels in the front and a hard wood block , threaded, to except the bolts.

I always have a plywood plate on the LE for the dowels. I'll dig for related photos now, but I have parts to a model not completed. I'll get photos of these parts. These photos have four bolts and no dowels. That works too!

WOW! I have no idea why these photos are this large? I've posted them many times and they posted small?

TedMo

Usually a single 1/4" dowel centered in leading edge of wing is sufficient there. At trailing edge a piece of hardwood glued as depicted in photo is good there. By using a hardwood it can be easily tapped for 1/4x20 screws. Do this by aligning wing in place then drilling through wing into wood blocks using the proper size drill for tapping 1/4x20. Then enlarge holes in wing to suit wing bolts.

Tall Paul

I've had single dowels at the front char due to vibration, and prefer two at the front.

Lnewqban

Pat,

Check this article with tips for good aligment:

http://www.airfieldmodels.com/inform...ruction/11.htm

speedracerntrixie

My Feedback: (29)

Pictures are worth 1000 words they say lol

1. Make sure you have a former in the fuse at the leading edge of the wing. If not make one up and pre drill, and make a plate of ply with matching hole size and spacing. I like 1/4" CF tubes.

2. Once the former is drilled/installed I use a small peice of double sided tape to stick the plate with matching holes to the former making sure the holes line up.

3. Test fit the wing, you will most likely have to notch the leading edge for the plate. Once the wing fits correctly glue the plate to the wing while it is in place. When the glue is dry remove the wing with the plate attached.

4. drill through the plate and into the wing, glue the dowls in place.

5. Install hardwood blocks or a ply plate in the fuse at the trailing edge of wing, install wing and measure for correct alighnment, drill through the wing trailing edge and into wing mount.

6. tap blocks to 1/4X20, ream holes in wing, re-inforce the wing trailing edge on outside with ply plate or glass cloth.

airbusdrvr

I agree here. I have both kinds, single and double dowel, and double is better. I stabilizes the wing better.

pat_willcox

Thanks for the replys. I now have a pretty good idea how to make this mod. Details later.

pat_willcox

I will try and posta few photos of the new wing mount.

pat_willcox

The project worked out very well. As always these simple projects take way longer than planned. I got both planes converted, test flown and buddy boxes working great. Thx to those who posted tips. I did not do photos on the Sig LT-40. It was a bit more of a challenge because the dowels had to be mounted below the wing. If I were not so keyboard limited, I would do a detailed how to.

Pat

SeamusG

If you haven't already, consider reinforcing the former at the front of the wing. I built an LT-40 kit per instructions and later converted the wing mount to eliminate the rubber bands. You have good access to the front side of the former with the tank hatch and tank removed.

pat_willcox

Hi SemusG,

Yes I did put a extra piece of 1/4 lite ply to reinforce the former. It all came out great and my friend who owns the plane is very happy.

I really like the way the LT-40 flys. I have been looking around to try and find one to use as my primary flight trainer. No luck so far on the various sites. I do not have time or energy to build one. >G

crossman

I recently coverted my Goldberg Eagle II to bolt-on wings. There was a page in the instructions to build it that way. I also built up the former in the windshield area to handle the stress better. The result was definitely worth the effort. Quicker, more consistent setup and better looks.

jaka

Hi!
Why!
High winged trainers are best with rubber bands until you can fly!!!
Then ...You can use dowels...but not wooden dowels! Aluminum arrow shafts (Easton) is much better and lighter too!

pat_willcox

Our club has about 5 trainers for use by our IP/Intro pilot. It helps to make a bit more user friendly and a faster set up. There is really not that much demand for the planes. When we do a big event hosting some Scout group or such, then the planes get a good workout. Normally most new flyers to the club have their own trainers (rubber bands GOOD idea).

Yesterday I did a bit more color trim on one of the planes, which really helps for keeping left and right and upper and lower wing for a new pilot. Actually it helps my rather ancient eyes also. I'll post a photo later.

partisan

My Feedback: (1)

When I built my plane, the guys that taught me to fly told me to thread the hold down blocks, then put thin CA in them, and then retap them. It makes the threads much stronger.