boat stuck in mould

this is my reply to watching gel coat go hard !!

Gel coat !
What do we really know about it !!
After it leaves the end of a spray gun and hurtles through the air at great speed towards the surface of a mould it pulling with it a column of air and has begun gassing already! The catalyst is working and bubbling within each droplet then it hits the mould and splatters ,all the drops big or small join together and then more and more until there’s thickness.
Now let’s pause here for a moment!!!
The size of the droplets of gel coat is quite important!! Fine spray and you get small craters as each drop hits the surface of the jellifying gel coat.
Coarse spray with big drops and when they hit it looks like the surface of the moon !!! the craters going almost all the way to the moulds surface , That gives you a rough finish , if you end up with this kind of thing you are best to second Gelcoat
Remember All problems are directly related to the operator!! he is the one person that has absolute control over everything that is taking place !!
On a vertical surface gravity is tugging and wants to make the gel coat slide and trickle down the smooth shiny waxed surface but the Thixotrophic agent that's added to the Gelcoat is able to support and hold its self ,But like all things it has its limitations as to how much it is designed to support .
I must mention that at this early stage if a mould just been gel coated never ever hit the outside of the mould with anything at all !
Why you ask?? Because the vibration can be sufficient to start a whole huge drift and totally destroy a perfectly good Gelcoat job.
Once Gelcoat starts to move its gathering momentum as it slides and more its slides the heavier it gets , just like a snow ball rolling down a hill side .
Given time it starts to congeal and gets tougher and will gradually stop somewhere!, maybe at the bottom or an edge and drips off .To help hold gel on the surface a quick flick of Gelcoat spray over the surface before you actually start to do the spray proper and a few second later an second flick , these droplets are usually able to help hold the gel better when you are spraying vertical surfaces . The gel coat has had time to semi jellify before the next lot goes over the top
The runs coat that's left behind usually when it slides and runs is thin and will need to be recoated with a brush as a second coat later!
If the operator has a heavy hand then this could happen in many places . plus if no side offs then pools and puddles in low places and when gel and cure takes place shrinkage is followed close behind and pre release and distortion etc etc !
Not a pretty sight to see the whole length of a cabin side combing shrunk away from the mould , pre-released and gone out of shape .
During early times thick gel was very common and if there were dark colours then when it went outside in the sun the Gelcoat mud cracked . This is very hard to cope with and is possible to repair but is not an easy process .
After the gel stage there’s the crumbly stage where the gel had solidified partially but hasn't got very much strength, any bubbles are unable to come to the surface and are captured within the gel for all eternity. This is where using the correct catalyst type and the correct catalyst ratio and correct thickness reduces the amount of gassing and also the length of time all this takes place!
If the gel coat thickness it to deep the bubbles are not able to reach the surface and burst and so you have porosity !,this is usually found later if you are doing repairs and you have sanded through the nice shiny top layer to reveal bubbles that usually get bigger the more you sand !!..

Most people dont even know anything about this !!
The crumbly stage is its most vulnerable stage!, it damages easily from dropping something in a mould on top of the semi soft gel or a bug lands and you try to pull it off and pull a chunk of gel as well as the bug !!, is best to do a quick mix and spot cover there and then .
Gel coat gels from the moulds surface to the top and at that stage it possible to actually very carefully and quickly start glassing . But only if you are gentle with your rolling . The gel is creating warmth and setting the resin to gel all in a chain reaction so if you understand all this it can be used to your advantage to speed processes up and get work done quicker !! Specially in colder parts of the world !!
Thin Gel coat takes longer to gel than a thick gel coat ,it’s mainly to do with the warmth generated by its self during the gel-ing !.Slow gel also takes the wax off the mould quicker and moulds loss the shine quicker .
Another inhibiting stage is the styrene that gases off from the Gelcoat !!, its heavier than air so if you have a hollow on your mould ,like most boat decks do !, or a mould with high sides like a hull and there’s no air movement then the styrene will saturate the air to a point and will slow and completely stop the gel hardening process !
( Just think for a moment when you do Gelcoat repairs do you use Styrene in your Gelcoat ?? most people do . I prefer to use acetone because It evaporates much easier and quicker and doesn’t hang round.)
So that’s as close as I can recall what I have observed over the time I spent watching gel coat go hard.

Australia has colour change white Gelcoat and that was great to use !!could see instantly because it was a pale shade of pink where it was still wet and changed to white where it had gelled !! a quick blast of air above the mould will disperse and shift the styrene and the colour changes in minutes .
Spraying !
Time to sort out a few other things when spraying gel coats .
With pressure pot spraying you have a greater control over the amount that can be put on by winding up the air pressure to the pot ,more product is forced up to the nozzle!
So high pressure ,more gel !!
This is also controllable by the needle in the gun head!, the further its wound out the less restriction so the more the flow .
So you have 2 ways of controlling the amount of flow .
Some people are not satisfied with that and will take it into their heads to want to thin the gel by adding a thinner!
Again styrene is the normal thing that is used.
What does thinning actually do ?
Thinner viscosity allows the gel to flow faster through the nozzle and can make it flow a little better !,more to the consistency of paint !, but in doing so it also has the effect of lowering the viscosity and the thixo in the Gelcoat is not able to do its job properly like its designed to do !!,
So runs and drifts are more likely to happen .
You solved one problem and created another’s.
Styrene evaporates slower so the gel retains more and therefore is diluted and coverage is not as good as it was .
It also changes the gel and it’s not as hard or as resilient as it was before
Acetone on the other hand will thin and allow a better flow and better atomization but by the time the gel has left the end of the nozzle and gets to the mould surface a much, much higher percentage has been evaporated out and so the gel is almost completely back to its original viscosity .
During my time as factory manager I worked very closely with our Gelcoat supplier and there chemists!! they came to observe and used our spray equipment and gain first hand how their products were being uses every day !!, during their testing they were able to make numerous test panels and was found conclusively styrene added to gel coat on their test panels was fractionally softer and the colour had changed ever so slightly !!,But panels thinned with just 2% of acetone were fractionally harder than the standard un-thinned Gelcoat .The colour had not changed at all !!. All this was quite an exciting find and also a mystery !!,the only theory was the pigment and semisolids in gelcoat were able to cling tighter together ! so from their findings and experiences learned in our company all Gel coats supplied from then on were laced with 2% of acetone !.

Any one seen a acetone recycler ?
The one we had has a bath with hot oil and a round 20 litre tin sat in the hot oil and when it reached a given temprature the condencer was able to distill pure acetone.!! the heater and switching was all duel set up so no way anything could over heat . it paid for its self in 2 weeks by recycling over and over again the same acetone , our consumption dropped from 20 drums a month to 0 the first month the little by little climbed to 6 drums after aboy 3 months and stayed about the same . Was really nice stuff to use and had no polutants or dirt or anything in it . Once the system was up and running in the morning i could do do 3, 20 litre tins before lunch time . Lerned to pour all the old acetone into a 44 gallon drum and let it settle and then fill the tins for the machine from there . the recycle rate was reall quite high. and the more acetone that the guys used the cleaner it became so the system worked even better .The recovery ate was above 80% closer to 90% so was able to just keep on doing what we were doing using it over and over again and just adding to the tins once in a while . .

Spray Technique !
This is a touchy subject and after you have read all that I have written i hope someone will have a greater understanding of the material and the spray equipment and what affects what and how to sort problems better , Maybe !!
Getting a even and consistent thickness on the surface can be a night mare. you are having to spray many different surfaces on many different angles ,the pressure pot spray is one of the best as you have only the weight of the gun and part of the weight of the two hoses feeding the gun . The gun will always spray at any angle all the time!
The distance away from the moulds surface governs the type of spray and the coverage you will get
To far away the spray is course as the bigger heavier drops of gel reach the mould and the finer drops get blown away with the air flow from the nozzle . To close to the surface and the strong air flow will make waves as it blows the gel along the surface !!,a part of this can be regulated by the air pressure regulator to the gun .
Using a fan width that's to wide for the amount of product being sprayed is bad as the spray pattern will not be totally consistent from side to side and it’s easy to get thin patches here and there and all over .
The fan width to narrow and you have a hard time getting a consistent even coverage . So again as always settings and spray technique is completely in the hands of the person holding the gun. if you are not 100% conversant with all the guns operations you shouldnt be there .
It's a case of the brain having to be two steps ahead of the hands movements. Stopping and starting with gel coat is not good there is a momentary delay as after the trigger is released and pulled again the gel starts to move along the hose again ,this is caused by the thixo in the Gelcoat !! its best to pull the trigger and keep spraying and using your brain two seconds ahead of you hand movements ,Visualise ahead of time where and what and how you will spray the next part of the mould .

If your cell phone rings don't answer it . Time has a habit of running away and gel time races up before you said bye bye and you have a gel up on your hands.
The guy at work here answered his phone and put the gun down and walked away and came back a while later !! too late to save the hose and had a massive cleaning job as the lot had gelled and was quite hard .
This guy is the head laminator of this factory I work !!
Cell phones have no place in any workshop anywhere !,I put a bucket of water by the door !!if a phone rings it gets the floatation treatment !,if it floats he can keep it !,if not ,you were warned !!!!

 

I'm stunned.

MM

 

That's quite informative.

Drifting off the theme here, but considering all the time it has taken to acquire that knowledge, do you ever wonder if it's about time for your lungs to set up?

In other words, what practices do you use (or maybe what is best) to keep all these highly toxic chemicals from damaging the health of workers?

 

Im impressed !! Thank you!

 

That was something i negelted to mention !!sorry
At a early stage of my glassing career fumes and getting covered incrap was just a part of working in glass . then i was introduced to a saturater gun and used to go home in the afternoon cover from head to toe with a fine resin spray and the only way to get if off was a long hot shower and lots shampoo . felt really good and the throughts of it being damaging to my health didnt seem to matter we were building boats .
later i was away from glassing for a year of so , when i came back and this time was shown how to use a chopper gun and all its joys of resin spray and as the glass roving was pulled from the roll at high speed and up through the eyes mounted along the boom i saw in the sun light a litteral cloud of ever so fine very small lengths of glass fibres wow !!!. so over time i gradually changed my techneque not to be any where near the boom and spray at an angle and the resin sprayed under high pressure makes it own draught and a movment of air is spraying along the mould the fine over spray was dirrected away and i didnt get hardly any spray at all !! so lesson 1 . over the time i have sprayed even with a gelcoat gun i use the same method of letting the spray carry its own over spray forward and along the mould and away from me !, its so effective as a operater very rarely can you even get a wiff or smell of spray .
Later the department of health was having a war on fibreglass factories and so we as workers we subjecter to being fitted with all kinds of ways of collecting samples of styrene laiden air and glass fall out .
There findings gradually built up a picture of the hell we were working in .
Like some one said a few posts ago his wife would complain about the smell of styrene even after a hot soapy shower!! the styrene was still in our systems !!, this is dangerous !!, body staturation its called !..
In later years spray booths had fans and exstractors . these are ok but are fixed in one place . for people working at home work in open spaces styrene is heavyer than air so have doors open if possible with a movement of air always . working inside tents during cold and humid conditions wear a really good 3M resporater with twin filters, write the date on the back of each filter . when not in use keep them in a clean safe place , you should never be able smell anything just 99.999% clean air .
Skin contact is just as bad !!,for all and any of the chemicals used in all products in the glassing industry . The humble mould release wax is something that i have never ever seen anyone ever worry about it but is laden with all kinds a nasties !!. Honey wax !! oh yeah !! just because the guy making the wax and dropped his honey sandwich in the mix??.

At home in New Zealand i am the oldest laminater i know and have this remarked to me a few times in recent years .
For one reason or another all the people i worked with over the years and have known have passed away for one reason or another ??.
All people i work with now i make sure they fully understand the dangers of everything we use . The humble Paper dust masks are totally useless and not even worth the time to reach into a box to get one out !
Most times they dont fit your face and so the dust simply get sucked in round your nose anyway !
Your 3M Resperator has dust fillters that can be fitted sperately or a dust fillter that get cliped onto the outside of your filter element ,these are excellent to use if you are spraying as the actual spray never reachs the gas filter . This is what i have and only use always !. There are wipes that are specially for keeping your masks clean a safe .
My mask is mine and i am the only person that wears it . The fit is completely air tight and i check every time i put it on my face there is a small air out at the very front and if you take in a deep breath and block the exhaust the mask will inflate untill it releases off you face to let the air out !proves all the flapper valves are working correctly
People that i work with ! if no mask ,no work !! simple and effective !
The company supplies and keeps spares so it is your responsability to take care of your own health and the health of the others you work with .
Its work habits that need to change they wont till you change them .!

 

got the honey wax and gave it 7 layers of wax and sprayed the pva on, im very nervous about this pva, i did exactly as tunnels described on another thread,

1, psi 110
2, half tap water, half pva,
3, opened the needle a quarter half way, seen very fine mist,
4, kept 2 feet away from mold and sprayed,
5, did not see any trace of any pva or water coming on mold, (this wat makes me nervous)
6, turned off the pva supply, left on the air and sprayed to dry the water.
7, walked away.

im going to leave it for an hour or two now and start the gel coat.

 

just read over the gel coat tunnels, its a science no doubt about it, very interesting read. think ill stay to spraying pva for the time being.
one question about the pressure pots, these are obviously bigger then the cups on the spray gun, would ye normally fill the pot to the top with gel coat, and if ye do would ye not get cought because of the geling time, or is it the bigger the quantity the longer to gel

 

if you did what was written all will be cool !

when you have been fiddling with the spray gun tell me something you should have noticed the first pull of the trigger !! What was it what happened ??? just about every spray gun on the planet has this action !! what happened ???? did you follow the steps for spraying the pva to the letter !!
i await your answer to the trigger action on the gun !! you must have noticed two things happened !! what here they ?:?::?::?::?::?:??

 

AIr comes out. YOUr making me get worried have I done something wrong? JUST say if I have

 

you need to re read the sheets i sent you !!!
follow the steps .
how many square meters surface area in you mould ???
if you run out of fingers to count on try a calculater and pencil and paper !!. For each square meter of surface area you need 0.6 kgs of gel coat to cover it !!
ok got that ?? simple ah !!
moving on !!
For every one kilogram of gel coat you will need 15ml of catalyst which will give you 1.5% which is what is recomended to use in Gelcoat .
if you haven done a gel test and found out how long your gel time is i would take a guess at about 20 to 30 minutes you should be done and ready to wash up clean up and put away !! dont for get to get the muld up on ots end and get the styrene out . never put the mould in the sun !!!! awaiting the answers to my questions !!
.

 

read and re read and read again !!!!

The pressure pot is also on the second part of the sheet i sent you . read it . sqr/mts = kilograms gelcoat to be used !!pour the gel onto a plastic container never into the actual pot !! how much catalyst ?? percentage is ??? there is a little bit of thinking involved here !!!!

 

i got no sheets my good man

 

Gel coaters check list for brushing !!!

Moulds to be gel coated should be clean ,waxed and polished!!
Pva has been sprayed and is ready to go ! 100% dry and dust free!
Do you have all the essentials that you will need, could need and if there’s a breakdown tools required right at you finger tips !!.

Ok list!!
Gel coat that’s the right colour and has been shaken and stirred and left to stand for a few minutes !
Is the gel coat cold from sitting on a concrete floor ,is best sat on a work bench up off the floor ,and been there for 24 hours as I could take that long to acclimatize to you workshop conditions .
If you are brushing then your brush’s need to have been soaking in acetone for a short time and then taken out shaken and gently dried 100% . for 30 minutes . Loose hairs, and dust all needs to have been washed out.
Plastic containers if they are new also need to be wiped with a clean rag and placed on a bench upside down, so they stay clean.
Gelcoat even new straight from the container could have congealed or thickened lumps in it so best to strain.
Panty hose or stockings are best ,or you can use cheese cloth !,even fine glass cloth !! These are all suitable as strainers. pull and stretch over the top of the container then pour the gel coat gently through till you get the amount you require !!,gently pick up the strainer material and drape over and inside the Gelcoat container so it can be used a second time if need be !!.
A good set of digital scales with a 0.00 scale for accuracy and totally cover completely with plastic that you can see through and tape in place.
Always be accurate with measuring and check and check again.
You should already know what the temperature and the humidity is from the wall dial as you walked in your workshop when you arrived !!.
This is what we have that hangs on the gun boom so everyone can see all the time !!,
Its pretty accurate for what it is and have checked it against a expensive unit that we have !!
Keep it clean and check throughout the day !!
Temperature can remain the same but the humidity levels can fluctuate considerably for many reasons!!.

Don't even have to think about this !!
Gelcoat 1.5% of catalyst so if you have weighed the gel on your scales and know the kgs !! Squeezed the catalyst measuring bottle and set the required amount
You have a battery drill with a clean painter stirrer attached you are ready to go .
Pour the measured amount of catalyst into the middle of the gel coat and begin to stir with your drill slowly to begin with. And then slowly speed up and move round and round in the Gelcoat container to thoroughly and completely mix. Slowly down to almost stop and slowly withdraw the stirrer stop and wipe clean and lay on the clean bench . from this point the clock is ticking !!,if you have done your home work and a little testing you will have a pretty good idea of the gel time !!,so with your egg timer set it 5 minutes less and pick up your brush and go !!!.
(Why pour the catalyst in the middle of the gel?? )
Catalyst if not mixed properly will cling to the sides of the container and as you brush you will pick up this unmixed catalyst and I gets wiper directly onto the mould !!
Unmixed catalyst can and does have drastic affects on the surface of the mould and can eat the wax away , can bleach the new Gelcoat and discolour it . non of these thing will be seen of noticed till the product is released from the mould and there will be a strong odour of catalyst !!
Poor mixing happens more so when using square containers than round !! You have to be 110% on the ball 110% of the time!!
Leave nothing to chance at any time !!!)

 

Gel coaters check list for spraying !!

Mould to be gel coated is clean waxed and polished!!
Pva has been sprayed and is ready to go ! 100% dry and dust free!
Do you have all the essentials that you will need ,could need and if there’s a breakdown tools required right at you finder tips !!.
Ok list
Gel coat that’s the right colour and has been shaken and stirred!
Is the gel coat cold from sitting on a concrete floor ???,is best sat on a work bench and been there for 24 hours as I could take that long to acclimatize to you workshop conditions .

Your spray equipment!!
Pressure pot spray ,complete unit!
Lets deal with the pot first !
Is best to find good sturdy plastic containers that will fit inside the pot !! so they can be placed in without dropping and lifted out with ease !
These containers will save lots of time cleaning ,and a lot of acetone or thinners. Plus is a way to check how well the gel was mixed and confirm the gel time !!

NO a plastic bag won’t work as it will get sucked up against the pickup pipe and block the flow of gel coat !!.

The plastic containers can be use many times, over and over again so it’s not just a use and throw away !!!!!
All the hold down clamps must be lightly greased and oiled and absolutely fee running at all times .
The rubber seal on the underside of the lid is best to have a light coating of Vaseline or grease so it will separate and come apart easy when it needs to in the case of an emergency or a accident happens like a blown hose and product is going every where !!.
The matting surface also should be lightly sanded with fine sand paper and almost shiny so its 110% clean and you get a good seal and no air leaks at any time !
The hoses need to be wiped down and reasonably grot free as much as possible .

Now the gun !!

The gun should have been soaking in acetone in a sealed plastic container and then reassembled and a light coat of Vaseline on the polished flow needle and all the fine threads that are on all the parts of the gun .
The needle I always polish to a bright shine as it slides and seals better, it gives far less problems with binding on the seal and wont slide properly.
Always things need to come apart quickly and cleanly to clear blockages and obstructions that can and do happen for various reasons like it or not!

The Flow control needle ,wound in and closed!
The air regulator to the gun needs to be completely off so nothing comes out, and the fan control also shut down as well.

The compressor should be turned on and up to its running condition and the drain tap shut !,Its best warmed up !


The line pressure to the pot system doesn’t need to be any higher than 70 psi so there is very little to no fluctuation of line pressure while you are spraying and the compressor tank pressure going up and down has little to no influence on the line pressure at all.
(The pressure fluctuation causes the gun to spray differently so the more consistent the less problems )

Air lines need to be laid out so they reach completely round the whole of the working area and not get tangled or caught up on anything at all !.Air line connections should all be a standard size so everything fits everything else and again operate freely and without hassles
Ready to go !!
Measuring and mixing is the same for brushing method!
Plastic containers if they are new also need to be wiped with a clean rag and placed on a bench upside down, so they stay clean and nothing falls inside.
Gelcoat even new straight from the container could have congealed or thickened lumps in it that are impossible to find by simply looking so best to strain all Gelcoat before using it !!.
Panty hose or stockings are best, or you can use washed cheese cloth!, even fine glass cloth is good !! These are all suitable as strainers.
Pull and stretch over the top of the plastic container then pour the gel coat gently through till you get the amount you require !!,gently pick up the strainer material and drape over and inside of the Gelcoat container so it can be used a second time if need be !!.
A good set of scales of digital scales is invaluable!! They need to be covered with plastic sheet that you can see through and firmly taped in place.
Always be accurate with all measuring and check and check again.
You should already know what the temperature and the humidity is from your wall dial as you walked in your workshop first thing !
This is what we have and hangs on the gun boom and is pretty accurate for what it is !!Keep it clean and check throughout the day ! Temperatures can remain the same but the humidity can fluctuate considerably throughout a day specially if you are near the coast or rivers and lakes !.

Don't even have to think what catalyst ratio you are going to use as it should never change all year round !,
Gelcoat is 1.5% of catalyst !, so if you have weighed the gel on your digital scales and know the kgs !! Squeezed the catalyst measuring bottle and get the amount you need for whatever kgs !!.
Catalyst bottle and measure !!Used properly is accurate and safer than most!!The small knob on very top lifts up to give the correct amount when the bottle is squeezed .as long as the slide pipe is not changed you get the same each time ! this a easy way of getting the same repeat amounts every time !
The care of all equipment is very important take care of it and will last a long ,long time.
Keep it clean so it’s easy to read and get the correct amount!!

Catalyst is dangerous and unpredictable so don't keep it in your workshop if you are not using for long periods of time.
Its unpredictable and will react with many things if exposed for a length of time.
Read and completely understand the safe handling and clean up procedures if its spilt anywhere on any surface .
Wear surgical gloves all the time when handling the bottles !!, just one drop left on your skin will give the worst most painful burn you can ever imagine!!
Even exposed to sunlight make it dangerous.
One company I worked the driver of the small work van had catalyst and paints and the usual things you take to do repairs all in a box together . He parked on the side of the road to get some lunch and on his return found a van filled with smoke and opened the door and let the air in and poof up in flames it went.

You have a battery drill with a painter stirrer attached so you are ready to go .
Pour the correct measured amount of catalyst into the middle of the gel coat and begin to stir with your drill slowly to begin with. Then speed up and move round and round inside the Gelcoat container to thoroughly and completely mix. Slow down to almost stop and slowly withdraw the stirrer!, stop and wipe clean and lay on the clean bench .
From this time on the clock is ticking!!if you have done your home work and a little testing you will have a pretty good idea of the gel time so with your egg timer,deduct 5 minutes off the actual gel time !, and place the Gelcoat and container in the pot , place the lid gently down on the pot and give it a twist to make sure the seal is seated properly !!. Flick up 2 of the hold down clamps one on each side and only tighten a small amount then the same with the other 2 and tighten firmly and then the first 2 firmly as well . the air hose can be attached slowly so air is in the system the pot is the first to be pressurized so check the gauge and screw to 20 psi through the clear of light coloured plastic hose you will see the gel moving along towards the gun pick up the gun and hold nozzle pointing to a empty container and pull the trigger and wind out slowly the flow needle till a steady stream of gel comes out, now the air that to goes to the gun !!,wind the regulator to about 40 psi and pull the trigger and spray .
It’s at this point that you have to be very familiar with all the control knobs on the gun what they do and what they are for .
You need to get you spray and pattern to what you want!! This is a personal thing and is dependent on the Gelcoat and the amount that will come out of the nozzle , it’s also the fan adjustment and the width of the spray you need to get the best pattern possible and make the best job!!.
High air pressure you get a fine spray but lots over spray with gel coat going everywhere .
Low air pressure you get a course spray and splatter’y looking and not a good fan width and quite rough on the surface as the drops are big .
All these setting take time to practice and fiddle with to get right .
There is no hard and fast rules that if the pressure is this ,that is what you get !!
What you have in the way of gel coats and whatever the spray gear you end up with will be quite different to what I have.
Tell and show me a problem Then I can tell you what is causing it but until you get some spray time under your belt I have my hands tied .
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Times to mix the Gelcoat , place the container in the pot and tighten down and start to set the gun ,adjust settings and spraying should all take about 5 to 6 minutes that’s all .

Second pot of gel !!,all settings will stay the same ,just mix in a new plastic container !!(set the egg timer less 5 minutes again ) ,place in the pot ,tighten down plug on the airline and you are away in 2 or 3 minutes tops and shouldn't have to adjust anything at all as you are just carrying on as before !!.
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(Why use a new plastic container for the second mix ?? it’s a way of checking the gel time of that mix !! The consistency of the mixing!
Any sticky or soft gel left means not mixed properly !!
And a way to make sure your containers are clean when you break out the hardened gel next day . You are covering you tracks with all and everything you do!!. )
Set the system you make for yourself and stick to it always.

Cleaning a pressure pot system !!
When you finished spraying and if all your calculations of quantities are right you should run out of gel coat just as you get to the end of the spray job !!
At that point when the gun starts to splatter and cough air and spit just keep it going till just about everything possible is out of the line and the gun !!
Remove the airline hose at the pot !, release the pot pressure and take off the lid . Remove the plastic container and put to one side , wipe down the pickup pipe with rag or even news paper to get the gel off the outside !!,
Have another plastic container with 500 ml of acetone and place in the pot and tighten down the lid !!plug in the air and re-pressurise the system and turn the air pressure to the gun completely off !! now there will be just a squirt of from the end of the gun ,acetone and gel come through the line so have a big bucket and quirt down the side until it spits and runs out !
Repeat the same thing with another 1litre of clean acetone and this time that acetone can be recycled and used for other cleaning ,let it spit and then disconnect the airline ,take the top off the pot and leave to one side .!!
If you intend to do more spraying during the day then it’s just a repeat of what you have done , if that's it and finished then the whole system needs to be cleaned totally outside and in .
The gun needs to be taken apart and cleaned and placed in its plastic container with acetone and sealed shut ,lightly grease the seal on the pot and leave it open ,put the whole thing in a place where it won’t get covered in crap and rubbish !
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Safety! And first aid !!
You need a proper eye wash bottle!and clean and full eye wash (its just a mild salt and water mix so make your own !) kept close to the door and some clean rag with it , keep your cell phone there as well with the ring sound off but in the case of a serious misshape everything is in one place and you should be able to find that place blindfolded !!
It's a good time to also do a toilet stop before you start any spraying as once you pour the catalyst in the Gelcoat you are totally committed to spraying and even if world war three lands in your back yard you don't stop for any reason at all until your finished and cleaned up totally

 

just poster . the trigger on any spray gun has two actions first when you partly pull the trigger just air comes outso you can use this to simly blow air and dust off the mould or what ever . pull the trigger back further and you get what ever is in the pot !!
one air !!
two air and material !!
release the trigger material shuts off and just air !!!
release even more the air shuts off completely . .