Thread: How to square a polycarbonate square

Hi Jill,

What a bummer! You'd think they could do better than that. I think the only real solution is to find a friendly machinist and explain the problem to him/her.

Allowing for setup time on a mill the whole job should take < 1 hour and give you flat square whatyoumacallums.

Gerry

Jill, as they are not square they are not fit for purpose. Take them back.

As above I would return them, failing that you could square them up yourself with a hand plane using a try square you know to be accurate

Hi Jill,

If your table saw and mitre are accurate you could use that to take a smidge off the two outside edges. Taking it off all the way along the inside edges would be a bit trickier.

Cheers

Bryan

You can use a variable speed router with acrylic bits of a jigsaw too

According to my knowledge of geography, returning them could be awkward. I think you should address your inquiry to Rockler, as their advert indicates "perfect 90 degree angles."

Cheers,
Joe

Hi Jill, I'm with Gerry and Bryan. Your Kapex with the delivered blade should do an excellent trim job, particularly if you use sacrifices (I've done it without). It will be quick and easy. Just watch out for the back corner. As for the flatness, I know nuttin about millin, but I can only see that you would have a lengthy polishing job after that. Put em out in the vicious Townsville sun for a few days, clamped flat onto a piece of granite or steel plate.

I don't believe you should have to return them to Rockler - take a pic of them with a try square on the corner to prove your point, email it to them and either ask for a full refund including freight costs, or a new set to be sent AFTER they have been individually checked at Rockler. Don't forget they USA will be desparate to get every $AUS they can get their hands on right now.

Regards, Brett

Oh yeah, don't tell 'em how friggin hot it is in Townsville (at any time of the year).

Jill

What a bummer

I'd send a note to Rockler - with the photo evidence
I'm also curious about what they might say

If they are negative I'll reconsider dealing with them, consumer boycott

G'Day Jill,
The add from Rockler says
"Align it, clamp it, and fasten it to get perfect 90 degree angles every time! Here's a solution that's so simple, you'll wonder why it took so long to develop! Align it, clamp it, and fasten it to get perfect 90 degree angles every time! Here's a solution that's so simple, you'll wonder why it took so long to develop!"
and from the sounds of it yours are way off the advertised prefect.
We used "polycarbonite" in the healthcare manufacturing business and from memory the temperature stability was excellant, so Townsvilles temperature range shouldn't be a issue at all. Has a look at the "wikipedia" description of polycarbonite it interested;
Polycarbonate - Wikipedia, the free encyclopedia.
Personally, the photo of the square with the jig and an email to Rockler sounds a good solution; they seem to be a very reasonable company in my deals with them.
Good luck, though you shouldn't need it.
Cheers, Crowie

Thanks for your advice and support everyone.

I have taken measurements of the error, and emailed them to Rockler.

On 4 of the units, the gap between the set square and the end of the bracket is 0.025". On 2 of the units the gap is 0.020", and on the final 2 items, the gap is 0.016". I have attached a photo to illustrate the items. In each case it would appear that there is a bulge near the right angled corner, a probable manufacturing defect.

Will be interesting to see their response

Maybe a silly question, but have you tested your square, ie the flip test?

Not all squares are created equal.

It did worry me when I found that 4 of them were out by about the same amount, so I tested the set square by a number of methods, using the flip test, an 8" engineers square, a sheet of foolscap paper, and a digital angle meter. It was spot on exact 90 deg

What does the inside look like for square? Does the distortion on the outside go through to the inside?

This are purely academic questions, and don't alter my belief that a refund should be requested.

Originally Posted by chrisb691

What does the inside look like for square? Does the distortion on the outside go through to the inside?

This are purely academic questions, and don't alter my belief that a refund should be requested.

Not purely academic, I think. The insides are the working surfaces, and they're the ones that matter most. Machining the outsides would have little effect on function.

Cheers,
Joe