I use the DrZ method on most of the wraps I've done. It is effective and does give you a little wiggle room to get it straigh. The one thing I would say is not to try and put the glue on the entire wrap as it will cause it to wrinkle or warp. The perimeter is the way to go...

Bill, interesting thougth about the scrapbooking tape. Plenty of stock available in my wife's SB'ing closet .... but I'd be afraid it wouldn't hold in the long run. Might be a good way to position the wrap for gluing though.... I'll have to give that a try.

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As will 3M; since removing it will remove some components of glue and all but ruin the 2nd attempt to re-place per lack of uniformity on the paper or substrate (glue residue). I guess I have had a lot of experience in veneering and or spray adhesives, so I have grown comfortable with having just one attempt to get it right. There are ways to support yourself as to afford the best possible result. Someone mentioned a tape or pencil line reference point. Additionally, standing the edge up vertically on said reference point will ensure you have the perfect starting point, and easily movable, to finally lay it down. But this is assuming the component is square and cut to exact specs.

Someone also mentioned spray glue getting underneath the paper and spitting of glue from the nozzle. As for the spitting issue, you should always turn the can upside down after (and potentially before) usage and spray until no more glue comes out. This cleans the nozzle for storage so there is no build up which is what causes spitting. Also, in some instances, you can also manually clean the nozzle with a damp paper towel; even a hint of acetone on the towel. This works well. Most of the time, this spitting happens when the can is sprayed at an angle and you should always keep the can as close to vertical as possible.

This is also a similar issue with the glue getting under paper. Spraying at an angle on a horizontal surface directs the air underneath the paper, rather than directly at the surface. So it will in fact get underneath the paper for an undesirable affect. There are a couple ways to combat this. Always spray at a parallel position, so the can and the surface of the paper will be at the same angle. This is as important in your side to side motion; you don’t want to force air/glue under the sides either. An additional approach, though it takes practice, is to prepare the table/board/cardboard; whatever surface you will be laying the paper on as to spray the glue. From 18 or more inches away, you can spray a VERY light dusting of glue onto the surface to which you will be laying the paper on. This is done via a quick spray in a fast sweeping motion. You are only looking to get a very slight dusting on the surface. You can then let it dry for a minute or so, and it will be tacky to the touch. When done properly, this will adhere just enough to the paper, that it will hold the paper down and not allow glue to get trapped underneath while spraying. Again it takes practice, and always test with your finger to see if any lifts off, but when done properly, the dusting you just created will not adhere to the clean surface you just mated it to. You can also look for removable double sided tape, but that is an extra expense; and still will not work as well…

Spray glue is a different animal to work with and it seems no matter if you have a paint booth, or not, some will stick to all available surfaces including arms, eyelids, or whatever is close by. That is also why I mentioned masking the 2nd mating surface being the rocket as similar to what you do when you paint.

In the end, everyone has a technique that works for them and you will get many different ideas based on that. In short, you know your limitations and or comforts, so do what works best, but don’t be afraid to try something new…

What is the tape you use? That would scare me on a permanent structure, per heat; environmental conditions, etc. I am open to new things though…

You sir, are better than me. My best attempt with contact cement was far from perfect, and I practiced the step multiple times before applying the adhesive.




That is the benefit of this discussion. We can all get a feel for what works and does not work for others.




I have not done it yet. There are two brands of tape available in the scrapbooking section of Michaels. Both are only 1/4" wide, however. So maybe a modifed Dr. Zooch perimeter taping?

One of the members of our Saturn 1B build team used it on the SM wraps. I have not heard any results from anyone flying the models or letting it sit out in the sun. He did say that the tape was thinner than a layer of glue would have been, therefore the wraps fit better.


Bill

Before hearing of the Dr. Zooch technique, I had always had better luck putting some Elmers white glue onto the body tube, spreading it out with the tip of a finger over the entire area to be covered (previously outlined with a pencil around the wrap temporarily positioned dry), then applying the wrap.




For permanence, you could try wicking some thin CA around the edges, if it is a paper wrap. Some warn against doing that with a plastic one.


Bill

LOL, not likely… I have blundered my share of projects and arguably, I have not performed the task we speak of with a cylindrical rocket… This adds a new dimension that will likely humble me…

An addendum to my use of 3M-90...

I didn't use it on both surfaces. I used it on just the back of the wrap and not on the tube. The 90 formula has a higher tack than the 77 formula, and I used it as a 'sticky-grab'. It is the thin CA that holds the wrap to the tube.

Sorry if my post wasn't clear.

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And prevents wrinkles and stuff under the wrap... his method works well... used it many times.

Later! OL JR

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I’m confused; which is not too odd… Are you guys talking about wrapping around the tube/substrate of a rocket you will be launching? That could make a huge difference in application I would suspect. In that regard, I am familiar with PVA and it is one of the best methods in attaching veneers. Do you heat it for the applications you speak of? If this were applied to the edge while using paper, would you not be able to see the transition between glued and unglued surface? Additionally, in finishing, I would think the paper could wrinkle or at a minimum show some lack of uniformity? And, if the model flies, if there is damage to the unglued area, you have a more difficult repair; potentially really bad since there is nothing to support the paper? In that regard, more damage than what would have occurred to an area that was secured, and more difficult to repair cosmetically since the stress of the accident could have deformed the paper?

Which reminds me; will heat from the motor impact PVA's integrity?

The addition of the wrap is usually a surface texture or pre-colored detail markings. The former being textured card-stock to represent the stringers on larger boosters and the latter being roll patterns or printed detail. In both cases the material is applied on to the body tube hence the tube is carrying the flight and structural loads, The thermal transfer through air and tube is quite low, with the exception of the explosive nature of the charge to generate the ejection overpressure. Delamination from those temperatures is low - my personal experience would rate it at zero

The decorative nature of the wrap renders the risk of damage quite low. The airframe would usually need to be delaminated before the wrap is at risk. If the body tube were to be zippered by the shock cord then the paper wrap is the last of the issues you would be dealing with. Also in our context PVA is usually seen as "White Glue" or "Yellow Glue"; neither of these require heating on our applications. Thinly applied Elmer's - which would be a finger smeared couple of drops would be sufficient to adhere. There is also a perceived benefit (as in I cannot prove it) that as the PVA dries and shrinks it applies tension to the unglued surfaces. Also bear in mind that in the majority case the wrap is either painted or at a minimum receives a clear coat to provide uniformity in the finish.

There are some wraps that are created from pre-printed label stock, or simply plain label stock. Both of the Pershing models which I produce are coated with a single layer of self-adhesive label to eliminate the spiral and better represent a moulded skin. The seam can e hidden under a handy conduit or filled with glue and sanded with 400 grit. In the final analysis the effort to reproduce is probably less than the effort to repair - that is if it not hanging on some tree (the ultimate destiny of al models).

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