Post by baronbeeza on Jul 28, 2015 23:00:50 GMT 12
I am sure there must have been some nasty stuff about in the 60's. Many here will be familiar with Turgostrip that would have been used from the 80's until recently. It was really unpleasant as far as health hazards go and didn't really do such a good job. If you got any on your skin you soon knew about it as it stung like acid. The worst was that it required several applications along with much elbow grease and still made a sticky mess on the floor. You would have to be careful with disposal and cleaning up afterwards as well.
We have it much easier these days, the waterblaster does so much of the job for you, at least as far as getting rid of the waste.
I am not sure how this Sunset Strip compares to the local 'Blue' stuff that we are using but the end result is the same. A very similar action and the inert nature of the product can be seen by the way he is applying it with minimal safety gear.
I have linked to this video before. You can see from some of the comments that people are having trouble getting used to this stuff being nothing at all like the older nasty products.
The stripper was certified to Boeing D6-17487, Rev P PDD 6-5 in May of 2010 by SMI lab in Miami, FL. ( Thanks Pat ) Passed Corrosion and Hydrogen Embrittlement Test for AL 2024, AL 7075 bare, Titanium, 4130 Steel. Do not use on parts made from Magnesium or AL 7075 clad. It will pit these parts if left on for over 1 hour for Mag and 12 hours for 7075 clad.
Last Edit: Jul 28, 2015 23:25:14 GMT 12 by baronbeeza
I don't mean to advertise or promote a particular product but I don't know of any other similar in NZ. Air New Zealand use this and Resene market some versions of the stuff also.
We have not used it on fibreglass, Royalite or other types of plastic. No-where in the literature does it say it is safe on such products so you would have to assume. I have used Tergo on fibreglass as it eats through the outer layers first, you just have to do very small areas and scrape and neutralise well before it gets even close to the gelcoat.
The Sea2Sky stuff just hates water and it stops the reaction dead. The difference here though is that seems to eat itself out from the base unlike other strippers.
Last Edit: Jul 29, 2015 17:13:42 GMT 12 by baronbeeza
I recall the Tomahawk being very docile to fly , almost like a car in its responses , and unlike a Tiger Moth which , like a hyperactive child , needs constant attention. I am alarmed that they come apart easily as I have been guilty of a bounce or three. Nice to see one cared for so well.
Early on in my apprenticeship at Rex we were doing an overhaul, and paint job on a C-172, and I got some stripper in one of the wheel spats, spent an hour or two re fibre glassing, and generally getting things restored to normal. Don't Do It.isc
Post by baronbeeza on Jul 29, 2015 22:38:28 GMT 12
NZ Jet and myself are at least two of the guys here that have been using this new generation stripper. It has more in common with hair shampoo than the strippers of decades ago. It is completely different stuff than many would imagine, or expect.
I am unsure why they mention helicopters, could it be because of the composites ?
It won't attack fibreglass like the nasty stuff does but the problem is that it has to be left on for many minutes to be able to work. You would want to try it on a scrap first to see what happens. By the time you see any action on the surface of the paint it has already been to the substrate and back up again.
SPC-909 Neutral is a water based coating remover which is environmentally friendlier and safer to use than traditional chemical strippers.
RECOMMENDED USE SPC-909 can be applied on coatings adhered to all types of aircraft including helicopters.
BENEFITS OF SPC-909 Netural
Non-flammable Water based User friendlier Replaces toxic chlorinated and caustic products Reduces health and environmental risk Biodegradable
I recall the Tomahawk being very docile to fly , almost like a car in its responses , and unlike a Tiger Moth which , like a hyperactive child , needs constant attention. I am alarmed that they come apart easily as I have been guilty of a bounce or three. Nice to see one cared for so well.
Yes, I remember testing the undercarriage in the same way. The Traumahawk did flare a bit like a brick though. I always thought it was a much better idea to be sitting on the main spar, in those instances, rather than hanging underneath like those other upside down planes.
Whats the stripper like price wise? I've just been using paint stripper from Mitre 10 (reacts and smells!) like the paint stripper of yore but only been using it on non- structural parts so far. Reading your commnet about Hydrogen embrittlement I think I'll bead blast the one leg I need to strip or use the stuff you have. Where do you get it from?
Post by baronbeeza on Jul 30, 2015 16:43:26 GMT 12
Some of the strippers can create problems with the high strength alloys and some spring steels. The Cessna Maintenance Manuals have a warning about the use of strippers on the legs, it may even be a Service Bulletin as well.
Temporary revision TR5 on the pre-1962 Cessna 100 series maintenance manual, p/n D138-1-13, specifies the procedures for cleaning rust from the gear legs. Basically NO chemical stripping. Top suface pits can be sanded to a max depth of .063". Bottom suface to a max .012" depth before having to re-shot peen.
I think the Tomahawk has something similar. I will have to have another look but it should have a caution or warning.
64.191.142.163/pub/piper%20SE/tomahawk/maintenance/761-660MM.PDF I have requested some revisions to the Tomahawk manuals and not all have appeared yet. The IPC was updated about 3 years ago but the MM is still at the 2002 version and contains a few errors.
I will get back to you on the stripper but for the amount you may need you could talk to someone at Air NZ. Resene sell it in 15 litre pails but at a little over $300. You would be able to use either the Aviation or general use product on the steel. Not cheap at $20 per litre but for a 'normal' aircraft it certainly saves a lot of time.
Last Edit: Jul 30, 2015 16:45:48 GMT 12 by baronbeeza
Nooo! Don't use paint stripper on fibreglass - ever, even if it says you can.
We used to use turco, nasty mustard coloured goop that burned when it came in contact with the skin, followed by a liberal wash down of MEK - cancerous mix if ever there was one. I remember Air NZ paint shop in CHC experimenting with this blue stuff that looked like shampoo that wasn't as toxic as turco and didn't burn, but it wasn't as good at cutting through thick layers of paint.
Post by baronbeeza on Jul 31, 2015 16:29:59 GMT 12
I did use stripper on the fibreglass but had many, many layers of paint to get through and it was on a car anyway. A Lotus that had been painted in a rainbow of colours over the years.
I stopped the reaction well short of the gel and it also had a very hard primer coat on it. That particular primer was not bothered by the Turco.
I would not be trying the same trick on an aircraft unless.... You had a large thickness, say approaching 2mm of paint. AND You had extensive gel coat cracking and were going to grind a lot of the fibreglass out anyway.
I found that with the 4" angle grinder you can literally rip through the paint anyway. You can go coarse just to remove the paint and cracks. I would then smooth the surface off and try and get a little shape back into it before adding more layers of lightweight cloth , or tissue, with the appropriate resin.
Those that have done a light aircraft engine cowling can tell you how much fun it is.... They all get a very good finish but again they all spend about 4 times longer than they thought in the process. It has to be the worst part of any repaint.
A few hours after work on a Friday night and the paint is well on the way to being removed. Much of it was fully loose and just hanging there while the stripper was still being sprayed on elsewhere.
Last Edit: Nov 6, 2015 20:42:12 GMT 12 by baronbeeza
When using an angle grinder for the more active reshaping or even paint removal, there are two options (not the standard grinding discs) that are helpful. I have used both of these while removing up to 6 layers of paint off my Rimu weatherboard 83yo home. The first is a plastic backing disc and round emery sheets - I used either a 45 grit or 60 grit paper to get through the latyers. On acrylics, these tend to "blind" the pad and then a burning/smoking sensation occurs! You can reuse the pad if you wire brush the caked on mess off - I used a small narrow wire brush and occasionally a scriber as well to pick the worst lumps off.
Secondly, there are "carbide poly" wheels as well - a curly mesh impregnated with carbides. These work particularly well and are more gentle than the emery papers and I used these after the emery pads on the same angle grinder to smooth out any grinding grooves caused by the emery process - and my enthusiasm! Those made by Norton now have a taper centre and don't seem to fit very well onto the grinder. You need these poly wheels with a flat inner flange face so they sit square and even onto the grinder backing flange. I found a supplier in Auckland for an alternative imported wheel. They do work particularly well, but if they catch on rough sharp edges at the perimeter, they can destroy themselves quite quickly and you have an immediate out of balance vibration!!
I can take photos of both systems and share here - I have some aviation business to attend to today!!
I'm sure you're aware Graeme, but you've got to be bloody careful paint stripping older houses, old lead based paints can be a major health issue and expensive pain in the ar$e !
A good day for it so went down to the paint shop at lunchtime. The first two pics were taken shortly after I arrived. One man in a few hours can hoover through the job. Wipe away (plastic scraper) the excess stripper and all the paint residue and then with a scotchbrite and thinners clean the surface.
We then had to fit the fuse back onto the trolley to take it outside for the waterblast and dry.
That is well less than a day's work for just one man. I can remember not so long ago that a it would take a team days and days to strip an aircraft.
This fuse has had the initial strip out of the way and now will be prepared ready to go into the rotisserie for the corrosion removal and minor repair work prior to getting primed. It is in remarkably good condition for a 35 year old aircraft and only has a few areas that need work. There are just small local patches of minor corrosion in about 5 areas, all in the expected places. Behind both steps and around some of the windscreen strip screws.
The first day was just supposed to be getting the bulk of the paint off prior to getting to work on the fuselage. As it turned out we had 97% of the paint completely stripped within 5 hours. The water wash removes the last traces but more importantly neutralises any remaining stripper. It is no more difficult than washing a car.
The next pics will be of the machine sitting in the rotisserie. We haven't tried it on an aeroplane yet so there will be some trial fitting going on during the week.
Last Edit: Nov 8, 2015 12:48:43 GMT 12 by baronbeeza
