Adjusting curing times?

[JHForman]

Ok guys, Lets say that I run my oven at 350 degs but the powder is calling for 400 deg @ 10 mins. How do you figure out how to adjust the time/temp ?? or like Dormant granny smith calls for 392 deg @ 10-12 mins how do you adjust for using 350 degrees? I choose to run 350 cause it only takes my oven 3-5 to reaheat back to 350 once the door has been opened. If I run at 400 it takes 10-18 mins to reheat.

and yes i know the cure time/temp is part temperature.

[JHForman]

Re: Adjusting curing times?

The Dormant Granny Smith is a Tiger powder, Series 49 TGIC Polyseter. Here's a link to the Tiger Drylac Data Sheets. Click the Series 49 Dormant/Trans pdf file. The data sheets provide you with a graph for cure time and temp.

http://www.tiger-coatings.us/index.php?id=1294

As a side note: depending on the powder you may have trouble achieving full cure at that low temp.

Ok well that settles that, I guess I will just have to suck it up with the reheating time

[Guest]

Re: Adjusting curing times?

What type of oven do you have?

[JHForman]

Re: Adjusting curing times?

If you looked at the data sheet and graph, you should/could cure the granny smith @ 356 (pmt) for 7 minutes. After it cools completely, apply your clear and full cure according to the cure instructions for the clear.

Each manufacturer's cure times can vary. You should be able to contact them and get some parameters concerning cure time and temp.

I did see that, but your comment about achieving the full cure for powders is what worried me. So I have no problem running the oven a little longer to make sure the part is fully cured.

[JHForman]

Re: Adjusting curing times?

What type of oven do you have?

Just a converted steel refrigerator. Its sealed up well, just doesnt have very large elements.

[Guest]

Re: Adjusting curing times?

How does the data sheets compare with PBTP products? Originally I learned you are suppose to fully cure your base coat period. Now I am learning if you are doing a clear coat not to fully cure the base coat. The only exception to this rule is if it's a metallic then a full cure is still required. Or possible cracking will result. Can you elaboate on this for me? (The curing part)

I hope this is still on topic.
Harley

[Guest]

Re: Adjusting curing times?

Wow nobody?

Harley

[Guest]

Re: Adjusting curing times?

Wow nobody?

Harley

My question would be, who told you not to fully cure the basecoat of let's day TGIC Polyester ? In my opinion it depends...

[Guest]

Re: Adjusting curing times?

Hey Harley, Do you feel sometimes you just can't get the answer you want??????????

Some where back on the doing bike frames. The can't take the heat type I was given the info of how to cure with lower temps.
Like add X mins per lower X degrees to get a full cure. If I remember right if you have a 400 powder 350 is as about as low as you can go even when adding the extra time. So you have around 50 degrees play is all to be on the safe side.

I think I found it. "doing bicycle frames"
I wouldn’t recommend lowering or raising the cure temperature more than 50 F. The rule of thumb is 1 minute for every 5 degrees (50 degrees lower, 10 minute increased cure time). Had a correction on 5 min and 10 min?

Now are you saying that some powders would not be sutiable to do this to?

[Guest]

Re: Adjusting curing times?

Each manufacturer's cure times can vary. You should be able to contact them and get some parameters concerning cure time and temp.

It's this simple

To fully cure or not fully cure:
As the King stated "it depends". There's too many variables to give a definite answer. Who's powder, what type of powder, is it a single or multiple color job, the type/mass of substrate your coating etc....................

Chempoint is where I got the info from way back when we were all looking into doing the high cost bike frames so it looks like you do get a full cure just takes longer as long as you don't go say lower than?? But you are right I guess that some powders might have to be a lot closer on to be right and the best way is to read what they say or call and make sure.

And if this dag rain and humidity would quit I might be able to do something. 70 degrees and 96% humidity is killing me this time of year and have two big and one small job to do and can't do sht 70 is not the norm maybe 40 to 50 and then look at where you are and your temps. Been there done that I guess I will just wait it out

Have a good one HD

[wiseguyz]

Re: Adjusting curing times?

I feel SOOOO sorry for you duke. It MIGHT get up to 10 (f) degrees today. Humidity is about 16%, so it makes back-ionization a real problem being so dry. As long as there's not enough snow to ride on, I'd much rather be "tolerating" your 70-degree weather.

Now quit your belly-aching and get back to work!

[Guest]

Re: Adjusting curing times?

I feel SOOOO sorry for you duke. It MIGHT get up to 10 (f) degrees today. Humidity is about 16%, so it makes back-ionization a real problem being so dry. As long as there's not enough snow to ride on, I'd much rather be "tolerating" your 70-degree weather.

Now quit your belly-aching and get back to work!

So dry air makes back ionization more likely? High or medium humidity better then?

Harley

[Guest]

Re: Adjusting curing times?

Each manufacturer's cure times can vary. You should be able to contact them and get some parameters concerning cure time and temp.

It's this simple

To fully cure or not fully cure:
As the King stated "it depends". There's too many variables to give a definite answer. Who's powder, what type of powder, is it a single or multiple color job, etc....................

Could you give examples? My original question was a base coat / clear coat? Are you saying there could be more times a full cure not be till the end? I'm just trying to learn so I can be good at this and know all the ends and outs.

Harley

[Guest]

Re: Adjusting curing times?

Could you give examples? My original question was a base coat / clear coat? Are you saying there could be more times a full cure not be till the end? I'm just trying to learn so I can be good at this and know all the ends and outs.
Harley

I typically partial cure epoxy based primers before top coating.
Fully cure metallics before clear.
I would fully cure if you plan to top coat with an Acrylic Clear.
If you were applying a gloss black and were masking areas to apply a matte clear (gloss/matte effect like Beebob did), you'd want to fully cure the base coat.

As the King says, some powders don't play well together, the acrylic being one. I seem to remember something about urethanes as well, but don't recall the particulars.

Anyone else with any thoughts? King......Auto-Cycle.....benwish.

Gee Golly HD you mean I got to do more research again You tough on a old goat Good job on explaining things I would say.

OK Harley I am going to start another post on the temp and humidity so we get it off this one. Me want to know also the best so you have the least problems any one

[Guest]

Re: Adjusting curing times?

Thanks HD thats the kind of stuff I'm looking for.


Glad to see you got my back Duke.

Harley