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AR vs. UR

Greg Curler

#12146

AR vs. UR | 24 March, 1999

I am looking into replacing another business division's Acrylic coating process with our Urethane coating process. Unfortunately, MIL-I-46068 doesn't differentiate AR/UR's performance, and the MFR data sheets don't match up at all (they each spec different cured properties). Are there any sources of comparison data out there? Our goal is a single coating process without having to requalify several products. (HumiSeal 1B31 & Hysol PC18M)

Thanks, Greg

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#12147

Re: AR vs. UR | 24 March, 1999

| I am looking into replacing another business division's Acrylic coating process with our Urethane coating process. Unfortunately, MIL-I-46068 doesn't differentiate AR/UR's performance, and the MFR data sheets don't match up at all (they each spec different cured properties). Are there any sources of comparison data out there? Our goal is a single coating process without having to requalify several products. | (HumiSeal 1B31 & Hysol PC18M) | | Thanks,

Greg: The two materials are kinda different. Check this out. Dave F | Greg |

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Graham Naisbitt

#12148

Re: AR vs. UR | 25 March, 1999

| I am looking into replacing another business division's Acrylic coating process with our Urethane coating process. Unfortunately, MIL-I-46068 doesn't differentiate AR/UR's performance, and the MFR data sheets don't match up at all (they each spec different cured properties). Are there any sources of comparison data out there? Our goal is a single coating process without having to requalify several products. | (HumiSeal 1B31 & Hysol PC18M) | | Thanks,

Greg,

Why would you want to switch from an AR (acrylic) to a urethane (UR)?

The acrylic works well and is pretty easy to repair.

Additionally, an AR has slightly better moisture resistance than UR and takes much less time to cure. UR materials generally contain TDI (toluenediisocyanate) which ain't really too pleasant. There is an exception to that in HumiSeal 1A33 but it still has a long cure time.

So why change?? Please inform.

Regards, Graham

Graham.Naisbitt@concoat.co.uk

Concoat Ltd Camberley GU15 2PL England | Greg |

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Scott McKee

#12149

Re: AR vs. UR | 26 March, 1999

| | I am looking into replacing another business division's Acrylic coating process with our Urethane coating process. Unfortunately, MIL-I-46068 doesn't differentiate AR/UR's performance, and the MFR data sheets don't match up at all (they each spec different cured properties). Are there any sources of comparison data out there? Our goal is a single coating process without having to requalify several products. | | (HumiSeal 1B31 & Hysol PC18M) | | | | Thanks, | | Greg, | | Why would you want to switch from an AR (acrylic) to a urethane (UR)? | | The acrylic works well and is pretty easy to repair. | | Additionally, an AR has slightly better moisture resistance than UR and takes much less time to cure. UR materials generally contain TDI (toluenediisocyanate) which ain't really too pleasant. There is an exception to that in HumiSeal 1A33 but it still has a long cure time. | | So why change?? Please inform. | | Regards, Graham | | Graham.Naisbitt@concoat.co.uk | | Concoat Ltd | Camberley GU15 2PL England | | Greg | | | | Boy, I'd have to agree with Greg. During my Aerospace years, we always pressed for AR because it's easy to use, more consistent, earier to rework (only requires IPA to strip), easier to clean up the equipment (maintenance), etc.

The only instance the we needed UR is when the assemblies were going through a secondary operation where IPA was used to clean the solder joints; the AR would be stripped, the UR would stay put. UR is very difficult to remove if you need to and MEK is not something factories like to have around.

So why the preferrence to UR? Is there somebody you don't like? Maybe you should look at replacing your UR process with the other division's AR process...

Anyway, good luck, Scott

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Scott McKee

#12150

Re: AR vs. UR | 26 March, 1999

Sorry, in the following message I'm agreeing with Graham - not Greg...

| | I am looking into replacing another business division's Acrylic coating process with our Urethane coating process. Unfortunately, MIL-I-46068 doesn't differentiate AR/UR's performance, and the MFR data sheets don't match up at all (they each spec different cured properties). Are there any sources of comparison data out there? Our goal is a single coating process without having to requalify several products. | | (HumiSeal 1B31 & Hysol PC18M) | | | | Thanks, | | Greg, | | Why would you want to switch from an AR (acrylic) to a urethane (UR)? | | The acrylic works well and is pretty easy to repair. | | Additionally, an AR has slightly better moisture resistance than UR and takes much less time to cure. UR materials generally contain TDI (toluenediisocyanate) which ain't really too pleasant. There is an exception to that in HumiSeal 1A33 but it still has a long cure time. | | So why change?? Please inform. | | Regards, Graham | | Graham.Naisbitt@concoat.co.uk | | Concoat Ltd | Camberley GU15 2PL England | | Greg | | | |

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Graham Naisbitt

#12151

Re: AR vs. UR | 29 March, 1999

Just for the record folks,

The customer I believe may be manufacturing stuff for refuelling rigs of various forms.

This being the case, the coating would need to be resistant against fuels and oils.

The UR material (at least ours!) is able to resist succesfully and is our recommendation. AR does not work in this condition as the fuels will destroy or at least damage the coating.

One more thing, you must cure the coating fully.

Regards Graham | | | I am looking into replacing another business division's Acrylic coating process with our Urethane coating process. Unfortunately, MIL-I-46068 doesn't differentiate AR/UR's performance, and the MFR data sheets don't match up at all (they each spec different cured properties). Are there any sources of comparison data out there? Our goal is a single coating process without having to requalify several products. | | | (HumiSeal 1B31 & Hysol PC18M) | | | | | | Thanks, | | | | Greg, | | | | Why would you want to switch from an AR (acrylic) to a urethane (UR)? | | | | The acrylic works well and is pretty easy to repair. | | | | Additionally, an AR has slightly better moisture resistance than UR and takes much less time to cure. UR materials generally contain TDI (toluenediisocyanate) which ain't really too pleasant. There is an exception to that in HumiSeal 1A33 but it still has a long cure time. | | | | So why change?? Please inform. | | | | Regards, Graham | | | | Graham.Naisbitt@concoat.co.uk | | | | Concoat Ltd | | Camberley GU15 2PL England | | | Greg | | | | | | | | Boy, I'd have to agree with Greg. During my Aerospace years, we always pressed for AR because it's easy to use, more consistent, earier to rework (only requires IPA to strip), easier to clean up the equipment (maintenance), etc. | | The only instance the we needed UR is when the assemblies were going through a secondary operation where IPA was used to clean the solder joints; the AR would be stripped, the UR would stay put. UR is very difficult to remove if you need to and MEK is not something factories like to have around. | | So why the preferrence to UR? Is there somebody you don't like? Maybe you should look at replacing your UR process with the other division's AR process... | | Anyway, good luck, | Scott | | |

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ScottM

#12152

Re: AR vs. UR | 29 March, 1999

How true, AR would not be the right choice...

Scott

| Just for the record folks, | | The customer I believe may be manufacturing stuff for refuelling rigs of various forms. | | This being the case, the coating would need to be resistant against fuels and oils. | | The UR material (at least ours!) is able to resist succesfully and is our recommendation. AR does not work in this condition as the fuels will destroy or at least damage the coating. | | One more thing, you must cure the coating fully. | | Regards Graham | | | | I am looking into replacing another business division's Acrylic coating process with our Urethane coating process. Unfortunately, MIL-I-46068 doesn't differentiate AR/UR's performance, and the MFR data sheets don't match up at all (they each spec different cured properties). Are there any sources of comparison data out there? Our goal is a single coating process without having to requalify several products. | | | | (HumiSeal 1B31 & Hysol PC18M) | | | | | | | | Thanks, | | | | | | Greg, | | | | | | Why would you want to switch from an AR (acrylic) to a urethane (UR)? | | | | | | The acrylic works well and is pretty easy to repair. | | | | | | Additionally, an AR has slightly better moisture resistance than UR and takes much less time to cure. UR materials generally contain TDI (toluenediisocyanate) which ain't really too pleasant. There is an exception to that in HumiSeal 1A33 but it still has a long cure time. | | | | | | So why change?? Please inform. | | | | | | Regards, Graham | | | | | | Graham.Naisbitt@concoat.co.uk | | | | | | Concoat Ltd | | | Camberley GU15 2PL England | | | | Greg | | | | | | | | | | | | Boy, I'd have to agree with Greg. During my Aerospace years, we always pressed for AR because it's easy to use, more consistent, earier to rework (only requires IPA to strip), easier to clean up the equipment (maintenance), etc. | | | | The only instance the we needed UR is when the assemblies were going through a secondary operation where IPA was used to clean the solder joints; the AR would be stripped, the UR would stay put. UR is very difficult to remove if you need to and MEK is not something factories like to have around. | | | | So why the preferrence to UR? Is there somebody you don't like? Maybe you should look at replacing your UR process with the other division's AR process... | | | | Anyway, good luck, | | Scott | | | | | | | |

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