I cut out three HDU signs 45''x48'' wednesday and sanded the edges, yesterday, ready for edge routing and left them all laying flat on the work table. I worked in the office all day and so didn't turn on the exhaust fan but did leave the rolldoor open. Went out one time and noticed it was 95 degrees. Closed up awhile ago and, passing by those signblanks, noticed that they weren't laying flat around the edges. So I tilted one up and noticed the whole signblank was cupped. Never seen this before. I turned them over hoping they'll pull back the other way.
It's got to be the heat right? Does it all do this?
Posted by Steve Nuttle (Member # 2645) on :
Wayne what brand of HDU are you using? Just curious. We use only Signfoam III and I have never had that problem but we don't usually get that hot in Jackson Hole.
Posted by Wayne Webb (Member # 1124) on :
Steve, It was Everwood. I did have a piece of SignfoamII cup one time but under different conditions. The sign was laminated to an alumacorr backer with epoxy and then painted with acrylic latex. I figured the paint pulled it but not sure. It's OK though. Once it was installed on the stucco wall, it's not noticeable at all. But it wasn't raw foam like this is.
I have thus far made one 5.5'x4'x3'' sign and a 5x2 sign from Everwood and neither of them has warped. Have so far bought 5 sheets of the stuff and have found no holes in it like the Signfoam II had. I haven't tried SignFoamIII.
It's got to be the heat. I'll check it when I get to the shop.
Posted by dave parr (Member # 3868) on :
Wayne, Are these for single or double faced signs? If the blank was intended for single face use, one might kerf the back every few inches, either horizontally or vertically, beginning & ending the groves a few inches in from the edges, (dimensions dependent on the sizes involved.) I have yet to try this myself & just wonder if anyone else has.
dave
Posted by Wayne Webb (Member # 1124) on :
Dave, I've never had to do that but have seen it done on redwood signs and it seems to work for that.
Posted by Amy Brown (Member # 1963) on :
Wayne,
They say HDU won't warp but they lie!!
I have seen at least two of the major brands warp just sitting on saw horses for an hour. Since I always make sure the weight is distributed evenly all around.
Of course we all know which one I hate the most, "********* *****". They never did fix my problem with the major cupping and warping back in January. I heard all the excuses for about three days and then I never heard from them again. Excuses dont' cut it with me. I don't want anything from them either. I just won't buy or endorse their product any longer. They also blamed the supplier like it's their fault the product stinks!
Sorry, no solution here!
Posted by Wayne Webb (Member # 1124) on :
Amy, Bet they told you it was the first time they've ever had any problem with that right? Never had any complaints before. Like you are the only one. Been there, heard that.
Just as I suspected, the blank which I flipped over yesterday evening has almost finished pulling back to a flat plane again. It must be something to do with the heat.
Any comments on this from the HDU reps would be interesting.
[ August 09, 2003, 12:55 PM: Message edited by: Wayne Webb ]
Posted by Roy Somers (Member # 403) on :
I read somewhere about one certain manufacturer who claimed that thier foam was the best because they let it sit in the mold longer to let it fully cure therefore preventing the cupping of the other foams.
Posted by Joe Cieslowski (Member # 2429) on :
I don't know if this will be helpful or not but I started a thread on Jan 15, "Testing HDU" and eventually recieved an explanation (From Sign Foam) about the different manufacturing systems for making the stuff. It's about the 16th post on the thread. I found it informative, if nothing else. Take from it what you will. No indorsements from me. I've tried them all but I don't make a living with any of them.
Joe, Makin Chips and Havin Fun!
Posted by John Smith (Member # 1308) on :
After many, many trials and tribulations with HDU.... I have found it very necessary to wash down BOTH sides of HDU outside and after a day of drying, prime BOTH sides. THEN, when cut to the required size, EACH SIDE must have the SAME amount of paint to "prevent" warping. When it comes to any closed cell product, temperature is the culprit. Precision Board says right on their HDU panel........... apply EQUAL coats of primer and paint to BOTH sides. I have had this problem only ONCE in over 10 years using HDU. Don't know if I am just lucky, or, I have stumbled upon the formula that works with HDU. Try it..........
Posted by TransLab (Member # 470) on :
great big pile of info there
Posted by Joe Cieslowski (Member # 2429) on :
Thanks for the assist Mike,
Before I die, i MIGHT LEARN HOE TO USE THIS FANCY TYPEWRITER.....Oppps
Joe, Makin Chips and Havin Fun!
Posted by Wayne Webb (Member # 1124) on :
I understand where you're coming from John, but these blanks have neither been primed nor painted yet. Just raw HDU lying flat on a big table.
Thanks for showing me the post Joe. That is very informative. I would like information like that on other manufacturer's processes as well as each one's own version of their products' physical properties in comparison to others. That would be interesting to see.
I put pieces of Precision Board, Signfoam II, Signfoam III and 'blast board'(a generic private label), on the table beside them this morning and it's supposed to reach at least 90 today. We'll see what happens
[ August 11, 2003, 09:57 AM: Message edited by: Wayne Webb ]
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