Bumper yaw string

[[email protected]]

I want to buy the "Bumper" yaw string but shipping from the usual suppliers want $30+ for shipping to Alberta, Canada. Can I buy direct from bumper?

[[email protected]]

Yes you can and its highly recommended, both the string and dealing directly with the Bumpmiester.

I made the mistake of buying my first MK IV from a certain Minnesotan company that charged an additional 'handling fee'. A handling fee....for putting a tuft of wool in an envelope.... Jesus wept.

CJ

[Sean Fidler]

:-)

[Sean Fidler]

Can you PM me the info for the direct buy please?

[[email protected]]

Sent to your gmail address.

[bumper[_4_]]

On Tuesday, November 24, 2015 at 2:34:46 PM UTC-8, wrote:
> I want to buy the "Bumper" yaw string but shipping from the usual suppliers want $30+ for shipping to Alberta, Canada. Can I buy direct from bumper?

I will sell direct, shipping to the USA is free, to most of the rest of the world it's $1 USD additional.

gmail is at

bumperjm

[Paul Remde]

Hi Curt,

I'm just doing my best to make a living. I need to pay my shipping
assistant. Very small orders take just about as much time to process as
large orders. Some days we ship a lot of small orders. We'd lose money if
we didn't charge the handling fee. Marking up all items would penalize
those who order multiple items. There is no perfect solution. I'm sorry
you weren't happy with the service.

Best Regards,

Paul Remde
Cumulus Soaring, Inc.
_________________________________

wrote in message
...

Yes you can and its highly recommended, both the string and dealing directly
with the Bumpmiester.

I made the mistake of buying my first MK IV from a certain Minnesotan
company that charged an additional 'handling fee'. A handling fee....for
putting a tuft of wool in an envelope.... Jesus wept.

CJ

[bumper[_4_]]

On Sunday, November 29, 2015 at 9:30:25 PM UTC-8, Paul Remde wrote:
> Hi Curt,
>
> I'm just doing my best to make a living. I need to pay my shipping
> assistant. Very small orders take just about as much time to process as
> large orders. Some days we ship a lot of small orders. We'd lose money if
> we didn't charge the handling fee. Marking up all items would penalize
> those who order multiple items. There is no perfect solution. I'm sorry
> you weren't happy with the service.
>
> Best Regards,
>
> Paul Remde
> Cumulus Soaring, Inc.


When I looked at my first glider, it was breathtakingly beautiful just sitting there - all except for the kluged bit of yarn stuck to the canopy with tape. It's a sickness, but I've always looked at such things with an eye towards, "How might that be made better?" And so the MK series was born in '98. Series, 'cause I kept finding ways to make it better until I was happy with it. MKIV now and I'm pretty happy :c).

Before Paul (Cumulus Soaring) took on the MKIV & QV, my sales were all direct, ras & word of mouth. Now, Paul sells fifty MKIV's to my one. That benefits us both, as I save time and hopefully it helps Paul's business in a small way. Cumulus Soaring, like any business, needs to profit, while for me it's fortunately just a hobby, a way of sharing one of my small inventions.

I will continue to sell direct, especially overseas where that makes sense as I can ship for the cost of a stamp. At the same time, I understand it's important to support our on-line soaring businesses, they provide an important service in a difficult small niche market. And most of the better soaring supplies carry "bumper" stuff - so when you place an order please add a MKIV too.

all the best,

[bumper[_4_]]

I received a private email asking why the MKIV is better than taped yarn and what improvements occurred between the various MK's. I'd like to share my response:


Were to start?!

Firstly I wanted to get rid of the tape. When tape residue hardens, it can be extremely difficult to remove. Clear tape is the absolute worst. UV degrades the plastic part and the underlying adhesive is like concrete. The plastic won't peel off but stays intact enough to "protect" the adhesive from any solvent one is brave enough to use on the acrylic. Denatured alcohol, applied briefly is about as brave as I can get. I've spent almost an hour removing one of those on one of *redacted - a famous supporter of soaring* ships. No thanks.

So there were two primary goals. Get rid of the tape and make sure that what replaced it would come off cleanly when that time arrived. Also the base should be completely clear. And shaped to help minimize static yarn static cling and keep it clear of the canopy in flight (no touching so no yarn "wipe mark" from fine scratches).

Initial change from MKI to MKII was shape only. The MKI was shaped like a baseball diamond, pointy end forward. The MKII is 3/4" long and pie shaped in a sense, it being cut from a 3/4 inch circle rather than a 1 1/2" circle (which would make it a real pie shape).

MKII to MKIII was an overlay plastic material change. But sill using semi-rigid plastics with a mechanically pressed yarn channel.

MKIII to MKIV changed to a softer plastic overlay (edit - less tendency to lift up off canopy at the edges), with a thermoformed yarn channel.

Subsequent improvements did not result in a MK number change, but included injecting a polymer into the base yarn after final assembly to help prevent yarn pull-outs. Not a common problem, but there were a few. There were a number of lesser improvements relating to assembly methods, mostly for quality, consistency, and for ease of assembly.

Included index dot (some use them to mark center line inside canopy) has changed from paper to plastic and finally to "white" reflective tape. Light color so it doesn't fool the peripheral vision into thinking it's another aircraft. Size has changed too, and is now 5 mm.

A recent change to a corner rounding punch to cut the rear radius was a complete flop. Could not make it do as nice a job trimming the clear double sided adhesive as doing it the old way by hand using scissors. It looked so good going in and I spent hours trying to get it to work. Can't win them all..

The shape, like one section of zig-zag tape, creates two tiny vortices to help keep the yarn "alive", while the .038" base thickness and yarn tunnel keeps the yarn from touching the canopy in flight.

There are some 30 steps in manufacturing each MKIV, along with a dozen primary jigs and fixtures and a number of custom made tools as well. All to make the job go a bit smoother and to insure perfect alignment of center yarn hole, yarn, base, adhesive, and a bubble free clear laminate. All resulting in a small thing that looks befitting of the ship it goes on.

all the best,

bumper

[Sean Fidler]

:-)

[[email protected]]

As a convert and owner - I don't understand why glider manufacturers haven't adopted the Mk IV as standard fit for new gliders.

[Martin Gregorie[_5_]]

On Tue, 01 Dec 2015 01:09:17 -0800, jpg797 wrote:

> As a convert and owner - I don't understand why glider manufacturers
> haven't adopted the Mk IV as standard fit for new gliders.

Agreed, and searching for and making improvements to anything is never a
'sickness', but a history of kludging stuff might well be one.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

[[email protected]]

On Monday, November 30, 2015 at 11:28:38 PM UTC-6, bumper wrote:
> I received a private email asking why the MKIV is better than taped yarn and what improvements occurred between the various MK's. I'd like to share my response:
>
>
> Were to start?!
>
> Firstly I wanted to get rid of the tape. When tape residue hardens, it can be extremely difficult to remove. Clear tape is the absolute worst. UV degrades the plastic part and the underlying adhesive is like concrete. The plastic won't peel off but stays intact enough to "protect" the adhesive from any solvent one is brave enough to use on the acrylic. Denatured alcohol, applied briefly is about as brave as I can get. I've spent almost an hour removing one of those on one of *redacted - a famous supporter of soaring* ships. No thanks.
>
> So there were two primary goals. Get rid of the tape and make sure that what replaced it would come off cleanly when that time arrived. Also the base should be completely clear. And shaped to help minimize static yarn static cling and keep it clear of the canopy in flight (no touching so no yarn "wipe mark" from fine scratches).
>
> Initial change from MKI to MKII was shape only. The MKI was shaped like a baseball diamond, pointy end forward. The MKII is 3/4" long and pie shaped in a sense, it being cut from a 3/4 inch circle rather than a 1 1/2" circle (which would make it a real pie shape).
>
> MKII to MKIII was an overlay plastic material change. But sill using semi-rigid plastics with a mechanically pressed yarn channel.
>
> MKIII to MKIV changed to a softer plastic overlay (edit - less tendency to lift up off canopy at the edges), with a thermoformed yarn channel.
>
> Subsequent improvements did not result in a MK number change, but included injecting a polymer into the base yarn after final assembly to help prevent yarn pull-outs. Not a common problem, but there were a few. There were a number of lesser improvements relating to assembly methods, mostly for quality, consistency, and for ease of assembly.
>
> Included index dot (some use them to mark center line inside canopy) has changed from paper to plastic and finally to "white" reflective tape. Light color so it doesn't fool the peripheral vision into thinking it's another aircraft. Size has changed too, and is now 5 mm.
>
> A recent change to a corner rounding punch to cut the rear radius was a complete flop. Could not make it do as nice a job trimming the clear double sided adhesive as doing it the old way by hand using scissors. It looked so good going in and I spent hours trying to get it to work. Can't win them all.
>
> The shape, like one section of zig-zag tape, creates two tiny vortices to help keep the yarn "alive", while the .038" base thickness and yarn tunnel keeps the yarn from touching the canopy in flight.
>
> There are some 30 steps in manufacturing each MKIV, along with a dozen primary jigs and fixtures and a number of custom made tools as well. All to make the job go a bit smoother and to insure perfect alignment of center yarn hole, yarn, base, adhesive, and a bubble free clear laminate. All resulting in a small thing that looks befitting of the ship it goes on.
>
> all the best,
>
> bumper

Whatever you did, Bumper, it works! Plus, the darned thing lasts forever (this would never happen at GM). Mine is a yellow synthetic string that's on the glider now for 4-5 seasons, 120 hours per year in the air. I had a spare that was aging in the envelope it was sent in, no need so far to use it so I gave it away. The attachment plastic is still clear after all this time!

[Dan Marotta]

A comment to Bumper's worries about tape residue:

I could only imagine that the tape on my 14-year old LAK-17a was
original to the ship and it was with great trepidation that I undertook
to replace it with a MKIV. As it turned out, the plastic part of the
tape simply popped off as easily as though it would have on its own on
the next flight leaving a huge mess of adhesive. With great care I
touched it with a finger nail and, to my delight, it simply flaked off.
It only took a minute or two of gentle scratching with my fingernail and
it was all gone! Then a bit of spit and a gentle rub with a microfiber
cloth and the canopy was pristine and ready for my new upgrade.
Couldn't be happier!

On 11/30/2015 10:28 PM, bumper wrote:
> I received a private email asking why the MKIV is better than taped yarn and what improvements occurred between the various MK's. I'd like to share my response:
>
>
> Were to start?!
>
> Firstly I wanted to get rid of the tape. When tape residue hardens, it can be extremely difficult to remove. Clear tape is the absolute worst. UV degrades the plastic part and the underlying adhesive is like concrete. The plastic won't peel off but stays intact enough to "protect" the adhesive from any solvent one is brave enough to use on the acrylic. Denatured alcohol, applied briefly is about as brave as I can get. I've spent almost an hour removing one of those on one of *redacted - a famous supporter of soaring* ships. No thanks.
>
> So there were two primary goals. Get rid of the tape and make sure that what replaced it would come off cleanly when that time arrived. Also the base should be completely clear. And shaped to help minimize static yarn static cling and keep it clear of the canopy in flight (no touching so no yarn "wipe mark" from fine scratches).
>
> Initial change from MKI to MKII was shape only. The MKI was shaped like a baseball diamond, pointy end forward. The MKII is 3/4" long and pie shaped in a sense, it being cut from a 3/4 inch circle rather than a 1 1/2" circle (which would make it a real pie shape).
>
> MKII to MKIII was an overlay plastic material change. But sill using semi-rigid plastics with a mechanically pressed yarn channel.
>
> MKIII to MKIV changed to a softer plastic overlay (edit - less tendency to lift up off canopy at the edges), with a thermoformed yarn channel.
>
> Subsequent improvements did not result in a MK number change, but included injecting a polymer into the base yarn after final assembly to help prevent yarn pull-outs. Not a common problem, but there were a few. There were a number of lesser improvements relating to assembly methods, mostly for quality, consistency, and for ease of assembly.
>
> Included index dot (some use them to mark center line inside canopy) has changed from paper to plastic and finally to "white" reflective tape. Light color so it doesn't fool the peripheral vision into thinking it's another aircraft. Size has changed too, and is now 5 mm.
>
> A recent change to a corner rounding punch to cut the rear radius was a complete flop. Could not make it do as nice a job trimming the clear double sided adhesive as doing it the old way by hand using scissors. It looked so good going in and I spent hours trying to get it to work. Can't win them all.
>
> The shape, like one section of zig-zag tape, creates two tiny vortices to help keep the yarn "alive", while the .038" base thickness and yarn tunnel keeps the yarn from touching the canopy in flight.
>
> There are some 30 steps in manufacturing each MKIV, along with a dozen primary jigs and fixtures and a number of custom made tools as well. All to make the job go a bit smoother and to insure perfect alignment of center yarn hole, yarn, base, adhesive, and a bubble free clear laminate. All resulting in a small thing that looks befitting of the ship it goes on.
>
> all the best,
>
> bumper
>

--
Dan, 5J

[JS]

Having purchased many* "Quiet Vent Kits" and one "Kiddie Car Tailwheel Kit" from Bumper, I remained skeptical about the yaw string until buying a glider with one already installed.
Great stuff.
Jim

* excellent gifts

[Jonathan St. Cloud]

Thank you much and very interesting. Just kind of shows anything can be improved, even yarn taped to a canopy! Perhaps you could do the same with the Quiet vent, how does that work. Just for full disclosure I did buy a Mark IV and a quiet vent, but have yet to install them and have never seen either in practice.


On Monday, November 30, 2015 at 9:28:38 PM UTC-8, bumper wrote:
> I received a private email asking why the MKIV is better than taped yarn and what improvements occurred between the various MK's. I'd like to share my response:
>
>
> Were to start?!
>
> Firstly I wanted to get rid of the tape. When tape residue hardens, it can be extremely difficult to remove. Clear tape is the absolute worst. UV degrades the plastic part and the underlying adhesive is like concrete. The plastic won't peel off but stays intact enough to "protect" the adhesive from any solvent one is brave enough to use on the acrylic. Denatured alcohol, applied briefly is about as brave as I can get. I've spent almost an hour removing one of those on one of *redacted - a famous supporter of soaring* ships. No thanks.
>
> So there were two primary goals. Get rid of the tape and make sure that what replaced it would come off cleanly when that time arrived. Also the base should be completely clear. And shaped to help minimize static yarn static cling and keep it clear of the canopy in flight (no touching so no yarn "wipe mark" from fine scratches).
>
> Initial change from MKI to MKII was shape only. The MKI was shaped like a baseball diamond, pointy end forward. The MKII is 3/4" long and pie shaped in a sense, it being cut from a 3/4 inch circle rather than a 1 1/2" circle (which would make it a real pie shape).
>
> MKII to MKIII was an overlay plastic material change. But sill using semi-rigid plastics with a mechanically pressed yarn channel.
>
> MKIII to MKIV changed to a softer plastic overlay (edit - less tendency to lift up off canopy at the edges), with a thermoformed yarn channel.
>
> Subsequent improvements did not result in a MK number change, but included injecting a polymer into the base yarn after final assembly to help prevent yarn pull-outs. Not a common problem, but there were a few. There were a number of lesser improvements relating to assembly methods, mostly for quality, consistency, and for ease of assembly.
>
> Included index dot (some use them to mark center line inside canopy) has changed from paper to plastic and finally to "white" reflective tape. Light color so it doesn't fool the peripheral vision into thinking it's another aircraft. Size has changed too, and is now 5 mm.
>
> A recent change to a corner rounding punch to cut the rear radius was a complete flop. Could not make it do as nice a job trimming the clear double sided adhesive as doing it the old way by hand using scissors. It looked so good going in and I spent hours trying to get it to work. Can't win them all.
>
> The shape, like one section of zig-zag tape, creates two tiny vortices to help keep the yarn "alive", while the .038" base thickness and yarn tunnel keeps the yarn from touching the canopy in flight.
>
> There are some 30 steps in manufacturing each MKIV, along with a dozen primary jigs and fixtures and a number of custom made tools as well. All to make the job go a bit smoother and to insure perfect alignment of center yarn hole, yarn, base, adhesive, and a bubble free clear laminate. All resulting in a small thing that looks befitting of the ship it goes on.
>
> all the best,
>
> bumper

[bumper[_4_]]

On Tuesday, December 1, 2015 at 8:23:41 AM UTC-8, Jonathan St. Cloud wrote:
> Thank you much and very interesting. Just kind of shows anything can be improved, even yarn taped to a canopy! Perhaps you could do the same with the Quiet vent, how does that work. Just for full disclosure I did buy a Mark IV and a quiet vent, but have yet to install them and have never seen either in practice.


Okay, briefly:

Soaring, should be serene and peaceful, at least when not doing a low save. When flying in the high desert, the experienced pilot should remain cool under the collar. And that Mecaplex flip-out vent sure was noisy, making a particularly bothersome low frequency noise.

The problem is caused by the air hitting the flip out vent, the back edge of the opening, the hinge block and the inside handle when the vent is open. All of the creates turbulence which impedes airflow and makes noise - in a glider that's supposed to be quiet.

The fix is the QV kit. It's made of clear plastic and when installed you won't notice it visually unless you look closely. The QV attaches to the inside handle of the flip-out vent and seals against and near the vent's leading edge to give the incoming air a smooth, rounded transition all the way into the ship. The flow is smoothed, less turbulent, and more air can enter more quietly.

To test in my ASH26E, I installed a QV, then at 60 knots measured the sound level at my ear level. Then, maintaining same speed, wasted a perfectly good QV by ripping it off and repeating sound level measurement. The reduction in noise was 10 dba! Each 3 dba represents a halving of sound pressure level, so dba is a quite significant reduction AND that irksome low frequency component of the noise was all but gone.

The QV was a winner! But, there were initial problems. The material I used at first was too thin, and any alignment error would have the QV acting like the reed on an oboe. This turned out to be quite unpopular, with some pilot ripping the damn thing out. Some others would go high in wave where even a gentle bumping of the QV would have it detach due to the extreme cold - - they were unhappy with me too.

Both issues were fixed of course, and there must be a thousand QVs are out there making soaring more enjoyable, or at least quieter when slowed up, hot, and trying to do a low save.

Price is $9 USD, and as with all the stuff I foist upon the soaring community, satisfaction is guaranteed.

The QV fits Mecaplex flip out vent. A version is available for the Antares on request.


I truly appreciate all the previous positive comments. Thank you everyone!

[Tango Whisky]

Am Mittwoch, 2. Dezember 2015 17:29:48 UTC+1 schrieb Sean Fidler:

> For what it's worth, I'm flying with 3 yaw strings now. Center left and right. When thermaling I'm never looking straight ahead and I also have a spare front string forward of the center primary. 4 total.

Whow.

[[email protected]]

On Wednesday, December 2, 2015 at 11:02:43 AM UTC-6, Tango Whisky wrote:
> Am Mittwoch, 2. Dezember 2015 17:29:48 UTC+1 schrieb Sean Fidler:
>
> > For what it's worth, I'm flying with 3 yaw strings now. Center left and right. When thermaling I'm never looking straight ahead and I also have a spare front string forward of the center primary. 4 total.
>
> Whow.

Triple Wow, he's one of a kind...
https://www.youtube.com/watch?v=fxt759HTp44

[bumper[_4_]]

Shaun the sheep video notwithstanding, if one were tied to a chair and forced to put up with that over and over, how long do you suppose it would take before you'd go stark ass bleating crazy?

Once upon a long time ago, it was postulated as to how natural wool yarn was less abrasive to glider canopies. I have not data one way or the other, but one could order natural wool or synthetic yarn for their MK#. Most chose natural wool.

I've tested yarns and found synthetic yarn lasts longer. I've also done testing of the MK# yaw strings, holding a curved acrylic surface out the window of my truck, to mimic a glider canopy, so I could view the string from the side. Due to the design of the MK# base, the yarn streams back maintaining the lift and separation imparted by the base, and looks to maintain that separation all the way back not appreciably touching the canopy at all.

With a normally maintained canopy, no scratching. If left parked out, uncovered, and with blowing dust or sand, I'd expect any string or yarn material might cause fine scratches. Loose covers can cause deep scratching.

[[email protected]]

Yes Thanks Bumper! I too bought a MKIV and am quite happy. Although I think Bumper might be unhappy with me, as I immediately modified it. I had problems with the previous MK II or whatever it might have been, snagging the canopy cleaner microfiber cloth I use, so I ever so carefully rounded the front point and beveled the edge of the plastic. I know what your going to say Bumper, I've completely ruined the aerodynamics of the thing. But I have to say it has stayed on now for at least 4 years with an avg of 200 hrs/yr :) But alas its now worn out as the yarn is completely unraveled and I had to tie it on the end (yes I am a cheap glider pilot). I was by the way the first one to ask and receive a white one! Do they come with a lifetime warranty :)

CH Ventus B

[[email protected]]

On Thursday, December 3, 2015 at 12:51:49 PM UTC, wrote:
> Yes Thanks Bumper! I too bought a MKIV and am quite happy. Although I think Bumper might be unhappy with me, as I immediately modified it. I had problems with the previous MK II or whatever it might have been, snagging the canopy cleaner microfiber cloth I use, so I ever so carefully rounded the front point and beveled the edge of the plastic. I know what your going to say Bumper, I've completely ruined the aerodynamics of the thing. But I have to say it has stayed on now for at least 4 years with an avg of 200 hrs/yr :) But alas its now worn out as the yarn is completely unraveled and I had to tie it on the end (yes I am a cheap glider pilot). I was by the way the first one to ask and receive a white one! Do they come with a lifetime warranty :)
>
> CH Ventus B

Ahh yes - the perennial issue of whether to tie a knot at the end of the yarn in the Mark IV. I tied a knot right at the end of my last one as it started to unravel a little but it changed the aerodynamics so that the terminal couple of centimeters or so waggled annoyingly. Then I tied a knot about a centimeter from the end and allowed the end to fray to create a little drag and that worked OK. My current one is still as delivered, hasn't unraveled yet and is performing well.

[bumper[_4_]]

The MKIV "high tech" yaw string length is about 7 to 8 inches (18 cm - varies a little due to the assembly process). I tie a simple overhand knot about 9 mm from the end of each yarn to prevent unraveling. In some fields of endeavor, 7 or 8 inches might be considered too long, so the MKIV instructions suggest cutting the yarn to your preferred length. AND to tie a knot in the end (please), or it will come unraveled in short order . . . it's just the nature of things and part of the cosmic reality.

All that said, a recent customer in France, with a DG-80X (you know who you are :c), ordered a MKIV custom made with a 40 cm yarn. With the canopy stretching almost to the nose on the DG, he wanted the MKIV base mounted in the distance while having the yarn where he could see it! He is currently the record holder with the longest yaw string in the entire world. Hopefully this won't become a "mine's longer than yours" trend.

bumper

[[email protected]]

On Thursday, December 3, 2015 at 5:31:33 PM UTC, bumper wrote:
> The MKIV "high tech" yaw string length is about 7 to 8 inches (18 cm - varies a little due to the assembly process). I tie a simple overhand knot about 9 mm from the end of each yarn to prevent unraveling. In some fields of endeavor, 7 or 8 inches might be considered too long, so the MKIV instructions suggest cutting the yarn to your preferred length. AND to tie a knot in the end (please), or it will come unraveled in short order . . . it's just the nature of things and part of the cosmic reality.
>
> All that said, a recent customer in France, with a DG-80X (you know who you are :c), ordered a MKIV custom made with a 40 cm yarn. With the canopy stretching almost to the nose on the DG, he wanted the MKIV base mounted in the distance while having the yarn where he could see it! He is currently the record holder with the longest yaw string in the entire world. Hopefully this won't become a "mine's longer than yours" trend.
>
> bumper

Aha - I cut them a little shorter and didn't think about there being an original knot

[Dan Marotta]

Bumper, a couple of questions:

How about dipping the end of the yarn in glue rather than tieing a knot?

At replacement time, how is the base removed without damage to the
canopy or residue left on the canopy?

On 12/3/2015 10:31 AM, bumper wrote:
> The MKIV "high tech" yaw string length is about 7 to 8 inches (18 cm - varies a little due to the assembly process). I tie a simple overhand knot about 9 mm from the end of each yarn to prevent unraveling. In some fields of endeavor, 7 or 8 inches might be considered too long, so the MKIV instructions suggest cutting the yarn to your preferred length. AND to tie a knot in the end (please), or it will come unraveled in short order . . . it's just the nature of things and part of the cosmic reality.
>
> All that said, a recent customer in France, with a DG-80X (you know who you are :c), ordered a MKIV custom made with a 40 cm yarn. With the canopy stretching almost to the nose on the DG, he wanted the MKIV base mounted in the distance while having the yarn where he could see it! He is currently the record holder with the longest yaw string in the entire world. Hopefully this won't become a "mine's longer than yours" trend.
>
> bumper

--
Dan, 5J

[bumper[_4_]]

On Thursday, December 3, 2015 at 10:15:22 AM UTC-8, Dan Marotta wrote:
> Bumper, a couple of questions:
>
>
>
> How about dipping the end of the yarn in glue rather than tieing a
> knot?
>
>
>
> At replacement time, how is the base removed without damage to the
> canopy or residue left on the canopy?
>
>
Dan (and all),

The MKIV base removes cleanly, leaving no adhesive residue, even after years of UV exposure. In '98 I did an exposure test with multiple strips, exposed 24-7 in the California sun, a strip removed every month or so. No problems as all.

To remove, start peeling off the top plastic layer, if need be, carefully grasp it with pliers and pull gently straight up. If this leaves the adhesive layer behind, and it commonly does, it will roll off with finger or thumb pressure as does that gooey glue stuff sometimes used on mailers.

A simple overhand knot (make a loop in the yarn, pass the end of the yarn through it, and pull up snug as you adjust the position of the knot - then tighten hard, does the job nicely.

If I were to use some sort of glue on the yarn end, as I do to secure the yarn within the base laminate "sandwich", it would need to be a soft glue material to avoid damage. Not just from the glue itself bonking the canopy, but from any abrasive dust or dirt that may be on either suface.

Silicone may be soft enough but its lack of weather resistance and tendency to attract and hold abrasive dirt rules it out. Having a treated yarn end would not allow the user to easily adjust the yarn length to their preference. A knot is not so bad!