HELP With TET612 Controller!!!!

[ed_denu]

Generally most powders have over-bake stability with the exception of clears and lighter colors which will both yellow if over temp.

I've also read a few times on forums that some people bake at a longer time at a slightly lower temperature and get good results. For example if the powder calls for 400 degrees for 15 minutes, they may bake at 350-375 for 25 minutes.

[SCOTTRODS]

Generally most powders have over-bake stability with the exception of clears and lighter colors which will both yellow if over temp.

I've also read a few times on forums that some people bake at a longer time at a slightly lower temperature and get good results. For example if the powder calls for 400 degrees for 15 minutes, they may bake at 350-375 for 25 minutes.

This is true. Many of the pwoders I buy, come with multiple cure schedules. Expecially Tiger Drylac stuff.

[wetdream]

So what would you say is a max over temp... Say if the part is 400 @ 10min??

It just seems my IR gun and the temp my TET612 is reading is about 50 degrees different at different times during warm up. Then there are other times when they are within 10 degrees of each other....

[SCOTTRODS]

So what would you say is a max over temp... Say if the part is 400 @ 10min??

It just seems my IR gun and the temp my TET612 is reading is about 50 degrees different at different times during warm up. Then there are other times when they are within 10 degrees of each other....

5-10 degrees is overtemp. If you're having issues with fluctuation, the highest number should be the cure temp,.... not the cure temp + 50,.... or 5 or 10 or any other amount. Extending the time is the way to deal with it,.... not raising the temp or allowing overtemp.

[wetdream]

5-10 degrees is overtemp. If you're having issues with fluctuation, the highest number should be the cure temp,.... not the cure temp + 50,.... or 5 or 10 or any other amount. Extending the time is the way to deal with it,.... not raising the temp or allowing overtemp.

So you would rather see the part temp to be a little under and in for as longer time period than for it to go over temp...

Would be nice if I could fix my temp probe right to the part that was coated?!

[SCOTTRODS]

So you would rather see the part temp to be a little under and in for as longer time period than for it to go over temp...

That's the best option. Just a little longer in cure time.

[wetdream]

That's the best option. Just a little longer in cure time.

So if that's the best way to go how do you know that the powder has been cured all the way?? Also how do you know how long is enough time when you are under temp??

[SCOTTRODS]

So if that's the best way to go how do you know that the powder has been cured all the way?? Also how do you know how long is enough time when you are under temp??

You don't know unless you have the oven that keeps solid temps. At least within a very close range. The one thing you can use to your advantage in this situation is that all the powders I have read the data sheets on, have excellent overcure ratings of 100%+. If you know you're under by 25 or 30 degrees, extend the time by a large enough margin to allow for the cure. If you have a bad feeling about it, double the cure time.

If you have any fear of having under-cure, do some testing with the powder you're using. Do some Rub tests, Bend tests, and scratch tests. Methods are readily available all over the web on that stuff. Even the data sheets say how much bend radius, scratch test parameters, impacts, and more, their powder will take. The rub tests using a solvent they should resist is a good start, a bend test should be easy, and the scratch tests are simple too. Salt spray may be a bit harder to test, but you can do some down and dirty tests that will allow you confidence in your powder curing.

I recently found that if a powder is not cured properly, I can cause damage to it wiping with acetone,.... If it's cured properly, the acetone will have no consequences..... Rub tests can be done that easily. Rub with acetone and see if it comes off on your rag. If it does,.... Undercured. Some Powders may not be Chemical resistant to that extreme, but most, I believe, are.

[JTW37]

I have one oven that gives me fits on temp control. Don't know why, but that is one reason I started curing at 375 (where 400 is the temp) for 15 min after pmt. Works out pretty good so far. Besides, it gives it more time to flow out.