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Don't try this at home update 2

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Hi Everyone

For those who were following the "Don't try this at home update 1" thread.

I received a sample of PROTOSTAR from Astro_baby today Thank you :headbang:. Again I set out to putting the flock under demanding and otherwise none normal conditions.

PLEASE NOTE: All tests were carried out on the PROTOSTAR flock sheet sample and had not been vacuumed (not recommended) or lint roller-ed to remove any dust or excess fiber from manufacture.

PROTOSTAR web site recommends after installation of their product that the material be cleaned with a lint roller to remove any excess fibers due to manufacture. For the purpose of my test I wanted to establish the absolute worst any shedding could be.

1) A high concern was the durability of the adhesive to stay stuck to the inside of the telescope wall. The test was for the self adhesive grabbing power of the backing.Although any kind of adhesive require some effort to be detached from a large surface area, the weak points are often the edges. In attempt to test the adhesiveness of the edges I stuck the sample to my hand and peeled several times to allow the skins natural oils and grease to contaminate and weaken the adhesive tackiness. I then attached it to a A5 diary 391g The adhesive instantly lost adhesion and it took several further attempts of heavy pressure to finally get it to hold the diary. The edges remained unstuck. I decided to try the diary test again with out contaminating the adhesive surface and the material stick with satisfactory results. VERDICT: The adhesive failed the test miserably while contaminated. Extreme care should be taken when applying PROTOSTAR and avoid contact with anything other than the intended contact surface. 3/10

2) Although I'm sure this would never happen once installed in a telescope I did the most obvious shed test... scratching across the fabric to establish loss of fibers. VERDICT: The sample had a small amount of loss the harder I tried. The amount of effort required to loosen the fiber suggests under normal circumstances no shedding would occur. 10/10

3) This test was to try and simulate stupidly rough handling of the OTA. I would assume heavy handling of the OTA would be more concern to the optics than any shedding of flock but never the less it could happen to fall out the back of a car and roll down a hill or something. The sample remained attached to the diary and I beat the life out of the back cover with a pen to see if fibers would shed onto a piece of white paper. VERDICT: This is where the PROTOSTAR sample came into its own. It took a ridiculous amount of effort to get even the slightest amount of fiber to shed. 10/10

4) The material was removed from the diary for the moisture test. The moisture test could be considered a little drastic but it was to serve two purposes. ABM inform me the material is synthetic. From what I am lead to believe this means there should be no concerns of mold. The test was to see if there were any waterproof properties to the material. This was not a good test for the PROTOSTAR sample as almost immediately the water soaked into the fibers and very little water formed into droplets. Only a small amount of water ran off with most of the water remaining soaked in. VERDICT: Dew may well occur on those cold winter observation sessions but I don't think it's going to have a puddle of water sat on the inside of the OTA. If you were caught in a shower make sure you have a rain cover as PROTOSTAR will suck it up like a sponge. 4/10

5) The water test was performed once more and the dried vigorously with the kitchen roll. This proved too much for the material and a good amount of shedding occurred, more so onto the the now damp kitchen roll I had just rubbed the surface with than the white paper but still a significant amount more than previous tests. Once dry a second time I tried the scratch test to see if the fibers had been loosened by the water. The result was worse than the previous scratch test although no where near as much heavy pressure was required to cause the fibers to shed. VERDICT: If you were to drop your telescope in a lake and you wanted to dry the flocking off DON'T!!!! Allow it to dry naturally or pat it with kitchen roll and clean with a lint roller to remove any newly loosened fibers. 3/10

6) The second reason for such a demanding moisture test was to see how the adhesive stood up to wet environments. Unlike the test performed on the ABM flock. As the adhesion was already none existent on the contaminated end of the PROTOSTAR sample this time the test was carried out on the uncontaminated end. VERDICT: Again the adhesive began to fail to the point the adhesive was peeling off in my hand. I did get the sample to stick with effort but the edges remained unstuck. It appeared as though the adhesive layer had shrunk when it came in contact with water. AVOID WATER AT ALL COSTS!! 1/10

7) CLEANING This was to be the failing test for the ABM sample. PROTOSTAR came through with flying colours and stood up well to the lint roller. Minimal amounts of fibers lifted and zero flock became detached 10/10

I am only a beginner like everyone was at some point and trial and error will be a inevitable part of my hobby. I do not have the long term experience of such modifications but samples are available so take my word for it, get a free sample and try it for yourself.

Although the average score from my testing will be shockingly low. Avoiding wet weather and under normal use I would score the flocking sheet from PROTOSTAR 7/10 for the intended purpose. I feel shedding would be reduced by 99% if prior cleaning with a lint roller had been carried out as shedding was minimal during tests anyway.

The overall feel of the PROTOSTAR sample compared to the ABM sample was of good quality and of a thicker feel. I think from examining the materials PROTOSTAR is an actual flock sheet with a sticky adhesive coating (glue) applied to the rear of it. ABM is a double sided adhesive sheet with a layer of flock fibers attached. Both have there failings due to adhesive properties. PROTOSTAR - the adhesive (only when moist) won't stay stuck to the flock. ABM - The flock won't stay stuck to the adhesive :o Although PROTOSTAR flock doesn't peel onto the lint roller would the sheet itself lift from the OTA. The advantage of PROTOSTAR over ABM is that you could always inject glue through the sheet to re-stick it. ABM would require re-flocking.:)

Adhesion was good and as long as it is not contaminated in any way including getting it wet. Correctly installed the PROTOSTAR sheet should cause no issues. Up most care would be required to keep the sheet dry at all costs. As the material is not organic I would not see an issue with mold but this would not be a test that could be performed unless over a long period of time. The only reason I would not give PROTOSTAR flocking sheet 10/10 is that you would have to give careful consideration to pre treating the OTA with further adhesive to ensure longevity of the PROTOSTAR adhesion. The material stood up very well to most shedding tests but was largely let down by the adhesive. PROTOSTAR SUGGESTS EXPANSION GAPS WHEN APPLYING THEIR FLOCKING http://fpiprotostar.com/ftp/fpinst.pdf I CAN ONLY HOPE THIS HELPS?



Revised test score for ABM flock overall is:


Members who have been following the thread will know it's not only about the material, customer service goes along way also. Although I have had a poor experience with ABM their self adhesive flock was found to be very good. If you had a cheap telescope you wanted to improve with out braking the bank then I would recommend ABM flock just DON'T TRY CLEANING IT with a lint roller as you will end up with patches of flock missing.


Comparing the two I would say PROTOSTAR offers only slightly more light grabbing against ABM. The feel of PROTOSTAR has more a feel of quality to it. ABM with out doubt would have better adhesion but you would not be able to clean the flock should the need ever arise. PROTOSTAR applied with additional adhesive would be the better option as it can be maintained better and offers a tiny bit better performance to-wards light absorbing and shown less shedding in tests. ABM flocking is a good alternative but only for a project or for improving a cheap telescope you plan traveling around with in the boot of your car. I Have ordered protostar flock for my 10" dob but would have liked to put Edmond's optics UK self adhesive Flocking sheet Light Absorbing Black-Out Material - Edmund Optics to the test but time is against me as my OTA is stripped and ready for application. Generally most adhesive bonds become stronger over time, I hope this is the case for PROTOSTAR

Update 9th Oct: I had left the sample attached to a zinc plated washer to see how well the adhesive would be given a few days hold. When trying to detach the flock from the washer the flock ripped and the adhesive backing remained. It would appear why the flock had a heavier feel over the ABM sample is due the flock having a card like layer in between the adhesive and the flock. I then out of curiosity tried to remove the card from the washer with water. The card came of no problem but the adhesive well and truly stayed stuck. I still feel there could be an issue if the flock comes into contact with moisture (bringing OTA from extreme cold out doors to warm indoors causing condensation) and it explains why the water test absorbed into the PROTOSTAR sample compare to the droplet forming of the ABM sample. If the flock comes into contact with water it will not be the adhesive that comes unstuck from the OTA more like the card core of the flocking sheet will absorb the water and as it dries, shrink and weaken possibly loosening from the adhesive. This to a certain degree could be fixed should it happen inside the OTA with a syringe and PVA glue.

Hope anyone who is in my position finds this thread useful and thank you to every one for your advice up to this point.


Edited by spaceboy
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