estes type shock cord mounts

Does anyone have a general rule of thumb on how far inside the rocket they generally go? Any size body tube so just generalize? Thanks!!

Usually they go in as far as needed to clear the shoulder of the nosecone. About 1 1/2 to 2 inches should suffice.

I Have used the glue bag style on a few of my larger Mid power rockets but instead of using paper to make the bag I used denum or canvas and wood glue. I had to remove one once because of a damaged body tube and just cut it off the the tube and relocated it.

Target said:

Does anyone have a general rule of thumb on how far inside the rocket they generally go? Any size body tube so just generalize? Thanks!!

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As far down inside the tube below the nosecone as you can get them... DEFINITELY down far enough to clear the nosecone shoulder at a bare minimum...

Use a stick to install them if you have to... Don't put it so far down it's subject to blast/heat from the ejection charge...

Later! OL JR

And don't let the folded paper/glue package dry before you install it in the body tube; it will stiffen up and be very difficult to make comply with the ID of the tube.
Do it all in one smooth step (if the instructions don't already tell you to do that).

+1 for far enough to allow room for the nose cone shoulder but not much farther. So the distance will vary somewhat depending on your nose cone. I find it harder to install them in BT20 (18mm) and BT5 (13mm) tubes because of the smaller diameter relative to my fat fingers. And Luke's tip on using a stick (or dowel or old paint brush handle) to press it down and get it to conform to the curve of the tube as much as possible is right on.

Thanks for all your help

KennB said:

And don't let the folded paper/glue package dry before you install it in the body tube; it will stiffen up and be very difficult to make comply with the ID of the tube.
Do it all in one smooth step (if the instructions don't already tell you to do that).

Click to expand...

I use hemostat clamps (with the jaws ground smooth so they don't "corrugate" everything) or spring clothespins, which also work well, to clamp the thing up tight while it dries. This keeps the "teabag" very thin and flat as it dries so that it doesn't stick out from the tube wall and hang up the chute or lines...

Once dry, you can conform it around your finger with a little pressure until it takes a curve and fits snugly against the inside wall of the tube... just conform it to your finger and then test fit against the tube wall interior a few times until you get the degree of curvature that you want. Apply the glue and install it...

Works like a champ! OL JR

When I teach my kids, this question always comes up. I simply tell them "as far down as your fingers will let you put it.". This seems to work, and I haven't run into any kids with fingers shorter than the shoulder on our nose cones

For BT-20 sized rockets I have to use my pinky finger to set the mount. For BT-5's I do the double slit method or tie it off on a ring and glue it down the tube. For larger tubes I use one of my longer fingers to set it in place. I have used the slit and poke on a few BT-20 kits just so I have more room for the streamers. Those things seem to unroll and act as a cork inside the tube. So I tend to put the slits below the streamers in the tube. This way the knot acts like a stop for the streamer roll.

KennB said:

And don't let the folded paper/glue package dry before you install it in the body tube; it will stiffen up and be very difficult to make comply with the ID of the tube.
Do it all in one smooth step (if the instructions don't already tell you to do that).

Click to expand...

Agreed. At some point I started making my folded mounts out plain old paper bag material. It folds very compactly and while the glue within the "bag" is still soft, I can dry fit it into the tube, rubbing the mount in and out until it conforms perfectly with the ID. Finally, once it is glued in place, it "snuggles down" and bonds very effectively to the interior surface of the tube (which is a material not too different than the paper bag). I have models from 30 years ago with paper mounts as good as the day they were installed, even though the rubber cord itself had long ago dry rotted.

Two more options: Cut off a section of BT and make a "baffle system." Before reattaching w/coupler, drop shock cord down through BT and put on your mount, allowing room for coupler. Now u don't have to contend with "wadding," or worrying if nosecone will go on. Other choice is not using it all! Attach shock cord, usually kevlar string, through a small hole in fin and epoxy down fillet. You may have to put a small notch in BT, to allow shock cord and nose cone to fit together.

garmtn said:

Two more options: Cut off a section of BT and make a "baffle system." Before reattaching w/coupler, drop shock cord down through BT and put on your mount, allowing room for coupler. Now u don't have to contend with "wadding," or worrying if nosecone will go on. Other choice is not using it all! Attach shock cord, usually kevlar string, through a small hole in fin and epoxy down fillet. You may have to put a small notch in BT, to allow shock cord and nose cone to fit together.

Click to expand...

If you notch the shoulder, you can leave the BT intact