# Removing sikaflex



## BillyPants (Jul 29, 2014)

Some years ago I had a steel plate sikaflex'd to the roof to use as a base for a satellite dish. I would like it removed now but no idea how to go about it. It's 4 feet long and about 3 wide. Anyone got any ideas?


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## Neckender (Jul 29, 2014)

Cheese wire, but with that size you would need 2 people to use.

John.


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## Deleted member 207 (Jul 29, 2014)

Try grinding down the steel plate -  if you have a month spare.

I'd give the Sikaflex people a call and get their advice, do you know which type was used?

When I've separated steel panels joined with some sort of Sikaflex the metal often gives way before the Sikaflex does. On a fibreglass (?) roof I'd be worried about destroying the roof before anything else.


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## RichardHelen262 (Jul 30, 2014)

Cutting,grinding then sanding then repainting thr roof is going to be about your only way with sikaflex,or just leave the plate there


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## mariesnowgoose (Jul 30, 2014)

Do you need to remove it for a reason? Like putting a roof light in or something?

If not I'd leave it. Metal can be painted or covered over easily enough


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## QFour (Jul 30, 2014)

You will probably do more damage trying to get it off than leaving it in place. Why do you need to remove it. If you are fitting something else then drill through it. If you manage to get one corner up then a thin scraper and just keep lifting and scraping. No way is it going to be a simple job. I fitted a solar panel to the roof and just used double sided tape and a bead of silicon round the edge.

Why did you need such a big plate in the first place 4ft x 3ft is some plate to mount a sat dish.

..


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## BillyPants (Jul 30, 2014)

The plate was part of the satellite dish assembly and was fitted when I bought the system. I'm not certain how much adhesive they used to stick it down, I didn't watch them do it. It's stuck directly to the aluminium roof and not screwed down. I knew it may be a difficult job, and had thought of a wire saw although I don't have one long enough.  

It's about 4 mm thick so I can do with losing it's weight now it's not needed, but the main reason I wanted it off was to put some flexible solar panel sheets on the roof. If I lay the panels with their edges on overlapping it I'm worried that this will affect performance with them not being flat. Does anyone have experience with flexible solar panels?


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## horshamjack (Jul 30, 2014)

BillyPants said:


> The plate was part of the satellite dish assembly and was fitted when I bought the system. I'm not certain how much adhesive they used to stick it down, I didn't watch them do it. It's stuck directly to the aluminium roof and not screwed down. I knew it may be a difficult job, and had thought of a wire saw although I don't have one long enough.
> 
> It's about 4 mm thick so I can do with losing it's weight now it's not needed, but the main reason I wanted it off was to put some flexible solar panel sheets on the roof. If I lay the panels with their edges on overlapping it I'm worried that this will affect performance with them not being flat. Does anyone have experience with flexible solar panels?



Ok don't shoot the messenger as I'm no expert and am in the throws of planning on doing my own system along with a few others here 
But what I have read from many other forums and the like, that flexible panels are not very efficient even with a MPPT controller
I looked at these originally to put over my luton and posted here sometime ago but having read so much negativity decided to go Panel construction 
Good luck with the REMOVAL of your roof  That Silkaflex is tough old gear


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## Flyboy (Jul 30, 2014)

*Removal of cured Sikaflex.*

If you visit Sika UK you can obtain downloads for the Sikaflex range that include advice on removal.  mechanical removal seems to be the only means to remove cured adhesive.


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## Deleted member 13867 (Jul 30, 2014)

Sikaflex is VERY tough stuff you will in all certainty damage the aluminum roof if you try to get it off. If you want solar leave the plate on and if possible straddle the plate with standard panels which are cheaper than flexible leaving an air gap underneath. this will solve all your issues barring weight. This plate may not be 4mm thick in its entirety but be thinner with a 4mm bead around the edge as a 4ft x 3ft solid plate would weigh a fair bit certainty too much for a product designed for mobile use.
Dave


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## horshamjack (Jul 30, 2014)

dr dave said:


> Sikaflex is VERY tough stuff you will in all certainty damage the aluminum roof if you try to get it off. If you want solar leave the plate on and if possible straddle the plate with standard panels which are cheaper than flexible leaving an air gap underneath. this will solve all your issues barring weight. This plate may not be 4mm thick in its entirety but be thinner with a 4mm bead around the edge as a 4ft x 3ft solid plate would weigh a fair bit certainty too much for a product designed for mobile use.
> Dave



Just noticed the plate size !! What was on it ? Jodrell Bank 
http://www.jb.man.ac.uk/multimedia/images/library/Lovell5_640x480.jpg


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## Fazerloz (Jul 30, 2014)

No wonder you want to remove it. 4mm mild steel plate weighs 31.4 kg per sq metre.


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## QFour (Jul 30, 2014)

dr dave said:


> Sikaflex is VERY tough stuff you will in all certainty damage the aluminum roof if you try to get it off. If you want solar leave the plate on and if possible straddle the plate with standard panels which are cheaper than flexible leaving an air gap underneath. this will solve all your issues barring weight. This plate may not be 4mm thick in its entirety but be thinner with a 4mm bead around the edge as a 4ft x 3ft solid plate would weigh a fair bit certainty too much for a product designed for mobile use.
> Dave



Biggest problem with fixed panels is the weight 100w fixed is 8KG and a bit extra for your fittings. Semi Flexible panel 100w only weighs in a 2KG .. so .. 25% of the weight which to the OP is important ..


OP Steel Plate if it is 4mm thick weighs something like 37KG why on earth did they put something up there that heavy. Perhaps it was something they had in stock. Did they cover it in Sikaflex or have they just done round the edges. As has been suggested a cheese wire. You could make one out of piano wire. Put a couple of handles on the ends and two people would possibly move it. Put some small wedges under as you go. When you have done stick your semi flexible panels over the remains.

..


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## hextal (Jul 30, 2014)

I'd absolutely leave it.

If it were me, i'd get a pair of 100W (solid frame type) monocrystalline solar panels and mount them to the roof plate.  I suspect that the feet of the panels could likely all be positioned so as to sit on your roof plate.

The flexible/flat panels are supposedly less efficient as they heat up along with the roof, whereas, the solid panel types stand proud by an inch or 2 so allow better cooling.

At the end of the day I suspect that the plate + 2 panels will likely be a fair bit lighter than the plate + the dish, so you are probably still better off than before.

Edit - scratch that last comment (looks like the dish may be lighter).

I'd still leave the plate though.


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## BillyPants (Jul 30, 2014)

horshamjack said:


> Ok don't shoot the messenger as I'm no expert and am in the throws of planning on doing my own system along with a few others here
> But what I have read from many other forums and the like, that flexible panels are not very efficient even with a MPPT controller
> I looked at these originally to put over my luton and posted here sometime ago but having read so much negativity decided to go Panel construction



Surely though a panel if it is 100 watts, is 100 watts? If it's not that efficient then it may be bigger than a more efficient panel. 
Or are you saying flexible panels take more sun to achieve 100 watts output in comparison to a framed panel?


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## horshamjack (Jul 30, 2014)

BillyPants said:


> Surely though a panel if it is 100 watts, is 100 watts? If it's not that efficient then it may be bigger than a more efficient panel.
> Or are you saying flexible panels take more sun to achieve 100 watts output in comparison to a framed panel?




Ok I could not find the original negative posts from the forums by people with experience with them but a simple search on goog  flexible solar panels pro's and con's brought this up

Types of Solar Cells

Also I believe I read  somewhere that because there is no air gap this is what leads to the under performance of output
I'm sure you will find people who have them and are happy .. They are more expensive .You take your chances 
Myself I was put off that I deleted the saved ones I was looking at on fleabay


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## QFour (Jul 30, 2014)

*Motor Home with Dish*

Dish must have been something like this ..




Suppose you could always take it back to the Dealer .....


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## molly 2 (Jul 30, 2014)

Have a word with a windscreen replacement company. They use long thin blades to cut out windscreens if it is bonded round the edge only it should not be problem. They can remove a windscreen without breaking it so steel plate may be possible.may be one of their lads would do it for a fee. They are very good at what they do.


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## BillyPants (Jul 31, 2014)

horshamjack said:


> Ok I could not find the original negative posts from the forums by people with experience with them but a simple search on goog  flexible solar panels pro's and con's brought this up
> 
> Types of Solar Cells
> 
> ...



That link states thin film is better under heat than framed panels. They're cheaper too, and a LOT lighter. My minds half made up...


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## Tbear (Jul 31, 2014)

I would not want 37kg of waste weight high up on my roof. Are you able to cut a corner off the corner of the plate to find out if its on an edge bead or a bed of silicon. I suspect that they may have just used a few dots underneath with an inch or so around the edge. If so a *sharp* Stanley Max Finish 9 in 1 Decorators Tool - Paint Spray Equipment, Spray Paint Equipment - Paint Spray Tools  may well see off the edge bead. Make sure its sharp side is uppermost or it will cut into aluminium. Use lots of wedges. A cheese wire would be your best bet to remove the dots underneath.

If its on a complete bed, Changing your Motorhome may be the easier option. 

Richard


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## BillyPants (Jul 31, 2014)

It's difficult to tell if they made a bed or just beaded it. I'll have a look this afternoon and see what I can see. Thanks for the help all.


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## Tbear (Jul 31, 2014)

I have not had much luck with oscillating tools on silicon as it moves with the blade. The blade will also scratch the aluminium. They are great for cutting plaster casts but I much prefer a sharp edge on silicon which cuts on contact and the blade is much longer but it would not hurt to try both.

Richard


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## paulhelenwilko (Jul 31, 2014)

Top tip, these tools have been mega expensive for a long time so have only been in the proffessional arena, or rich diyers ! I beleive that the patent has expired so more 'reasonable priced models are available.

I bought one from Aldi for under £30 ! it does me fine - it is a diyer's (bodgers) dream for the 2 or 3 occasions a year I need it !


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## donkey too (Jul 31, 2014)

I don't want to be Mr Doom and Gloom but, The first thing I would think of is why they put the plate there and what's it hiding?


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## BillyPants (Jul 31, 2014)

The plate was there to mount the satellite dish on. It withstands speeds of up to 50mph so needed a sturdy base rather than screwing into the roof.


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## QFour (Jul 31, 2014)

BillyPants said:


> The plate was there to mount the satellite dish on. It withstands speeds of up to 50mph so needed a sturdy base rather than screwing into the roof.



So you can have the dish up in a GALE FORCE 9 and watch TV. If its like we had on the cliffs in Cromer this year you would be worried about the MH more than anything else. Must be on some stand to withstand that sort of treatment. We have one of the crank up ones and if the wind gets up we just wind it down. I have forgot on the odd occasion and left it up but it has not come to any harm. Think your fitter was being a tad over the top when they fitted that.


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## horshamjack (Jul 31, 2014)

BillyPants said:


> That link states thin film is better under heat than framed panels. They're cheaper too, and a LOT lighter. My minds half made up...



There is another thread going at this time re Solar with this link A & N Caravan Services : Solar Panels
"Note that a Solar panel is more efficient at lower temperatures so ideally you should provide an air gap below the panel for cooling. 

One of the reasons why semi-flexible panels are disapointing performers in bright sunny conditions is the heat build-up due to a lack of air space below the panel as these flexible panels are normal bonded directly to the roof"

I'd be interested to know if any other members have flexi panels installed and their views tbh

So is your glass still half full or half empty


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## BillyPants (Jul 31, 2014)

User1 said:


> So you can have the dish up in a GALE FORCE 9 and watch TV. If its like we had on the cliffs in Cromer this year you would be worried about the MH more than anything else. Must be on some stand to withstand that sort of treatment. We have one of the crank up ones and if the wind gets up we just wind it down. I have forgot on the odd occasion and left it up but it has not come to any harm. Think your fitter was being a tad over the top when they fitted that.



It was for internet, not TV. But yeah it was pretty sturdy lol
Shame it was unreliable.


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## Tbear (Jul 31, 2014)

Whether you use Davids oscillator or my old fashioned tool (had the same one for 30 or more years) the key is to keep it sharp so I would have a diamond file to hand.

Richard


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## n brown (Jul 31, 2014)

i have done something similar . i used a bimetal hacksaw blade,one end of which i ground to the same shape as a bayonet fit jigsaw blade. this gives you a very long blade to put in the jigsaw,and it's flexible enough that the saw can be held at an angle to the job,have some silicone or ptfe spray handy to keep it moving. very cheap to try !


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## BillyPants (Aug 1, 2014)

I may have a simple way around this if I can't get it off. I have been thinking of buying the plastic mounts for framed solar panels, and using them to hold thin flexible ones. At least there's air flow around them and I save about 50 kilos of weight if I get 3. Doing it this way means I don't have to remove that plate, which saves a huge job.


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## BillyPants (Aug 2, 2014)

Well you did miss it yes, but I've got it wrong anyway. I've just been rechecking all the details and I'd initially written down 20 kgs for rigid panels. But that was the 200w panels and they won't fit. The flexible panels allow it to go along the front part of the roof, then follow the curve down towards the centre of the roof. Even using frame mounting brackets it could still easily follow the curve allowing larger panels to be fitted, but without having to stick them to the roof aluminium. Also of course the flexible panels are less than 3 kilos so there was a great weight saving. However, like for like wattage means rigid panels are about 8 kilos, which is about 5 kilos heavier than flexible ones. So I'd be saving 15 kilos in total, which is a canny saving considering it's on the roof therefore way above the centre of gravity. Not as great a saving as I initially thought but still useful. 

Also when you talk about efficiency, that's a relative measurement. Yes some panels are more or less efficient than others, but a 100 watt is still a 100 watt. A less efficient panel may be slightly larger, but it will still provide the given wattage. So efficiency is only a factor if your space is ultra limited. 

Flexible panels are not that much more more expensive, but if being flexible means you can fit more in the space you have, that's a reasonable trade off. 

The document in Horshamjack's link to A & N Caravan services states that heat build up due to lack of space under a bonded flexible panel is a cause of poor performance.However the link he gave prior to that at pierrosolar.com stated that flexible panels perform much better at high heat. So at this current moment I'm not sure which of those statements is correct. I would actually expect something non-rigid to be less likely to be damaged than something rigid. 

I'm still awaiting some emails back regarding the heat build up if they're bonded to the roof.


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## BB02TON (Aug 2, 2014)

*sikaflex removal*

Our satelite plate was fixed onto the roof of our caravan . When we bought the motorhome and wanted the satellite refitted onto it the dealer said we would have to purchase a new metal fixing plate as you can't get the old one off. When told a new plate would be £90 my husband spent a couple of hours doing what a friend had done previously that was heat the plate up with a hot air paint gun and as the sikaflex softens cut through it with a sharp carvings by knife. This he did and eventually managed to remove the plate. Then he sanded down the roof and resprayed it and it looked like New . Couldn't tell the. Plate had been on there. Then spent a little time cleaning the plate up before if was refitted. The dealer couldn't believe he had managed to remove it but said his couple of hours work was worth saving £90. So it can be done. That's two people I know who have removed it


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## BillyPants (Aug 12, 2014)

Right. I've had a try at removing this plate, I bought a bow saw blade, fashioned a handle and used it to cut through the Sikaflex under the plate. However after 40 minutes and only cutting out a small corner about 1/4 inch deep, and realising that continued work would cut through the aluminium roof skin, and there is the matter of 14 screws which go into the roof therefore need to be resealed, it was apparent that a removal attempt is not of any value whatsoever. I've decided to make a strategic withdrawal and just secure the panels over the top of it! 
All comments and advice have been appreciated though 

In addition after reading the comments on here and scouring the web for info I decided to buy 3 x 100 watt rigid frame panels from Biard for £351. I've since spent the same again on MPPT controller, cable, mounts, bolts and all the other sundries necessary to complete the installation. Neither the frames nor the mounts come pre drilled so there was a lot of drilling, but the job is stopped at the moment as one of the panels was missing it's weather seal on the connector so I'm waiting for a replacement. 
Hopefully they'll be done by this weekend!


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## Beemer (Aug 12, 2014)

BillyPants said:


> In addition after reading the comments on here and scouring the web for info I decided to buy 3 x 100 watt rigid frame panels from Biard for £351. I've since spent the same again on MPPT controller, cable, mounts, bolts and all the other sundries necessary to complete the installation. Neither the frames nor the mounts come pre drilled so there was a lot of drilling, but the job is stopped at the moment as one of the panels was missing it's weather seal on the connector so I'm waiting for a replacement.
> Hopefully they'll be done by this weekend!



Wow! 300 Watts!
What sort of set have you got that requires 3 panels?
They will take up a lot of space on the van roof.
Curious


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## Fazerloz (Aug 12, 2014)

Are those costs including your batteries or not. :cheers:


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## BillyPants (Aug 12, 2014)

Beemer: I run a computer 40 hours a week minimum for work, that's my main usage. It costs me upwards of £20 a week to power the gennie so I'm hoping the panels are going to help in cutting that down.

Fazerloz: No I already have 2 fabulous batteries. They cost almost £500! No wonder I'm always skint!


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## Siimplyloco (Aug 12, 2014)

BillyPants said:


> I've decided to make a strategic withdrawal and just secure the panels over the top of it!



I was faced with a similar task when I fitted the 100w panel on Hugo last week. The old sat dish mounts were left in place and the panel sat neatly over the top, the new brackets providing more than enough clearance. Why give yourself a hard time......?
John


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## Habby (Aug 17, 2014)

*Sikaflex removal is easy!*

With a few years under my belt as a boatbuilder, I've removed loads of sikaflex. It's easy!

Heat it up, be patient. Ideally use an adjustable heatgun (DeWalt make a great affordable one) so you can set the temp just below the temp where you'd scorch/melt the paint/wood/finish. Start from one side and as the sika softens you can start prising up the bonded item. As you lift the heat penetrates a little further and in a bit you can lift a little more etc. Ratchet straps can be handy for applying a constant pull on something.

Once you've removed the item, keep the same temperature gun on the remaining sika and it will clean off with a decent firm scraper.

It is just as case of finding the right temperature and being patient enough.

Habby


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## n brown (Aug 17, 2014)

cheers Habby,always good to get another tip !


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## Fazerloz (Aug 17, 2014)

That's one big piece of steel  4`x 3`x4mm to heat significantly to effect the sikaflex with a heat gun, whilst pulling against a thin aluminium roof panel. Its not as if its a small item that's stuck on, but hey if its easy then its easy. :have fun:


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## Fazerloz (Aug 17, 2014)

I quite agree with that. :cheers:


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## Polar Bear (Sep 6, 2014)

I would get a cheap band saw blade from somewhere like Machine Mart and brake it at the weld and take each end in Vise Grips and then use it as a wire saw.
 If you are covering the roof with SP's then paint roof with aerosol paint before fixing them.


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