Question about "pins" method for joining acrylic, i need help. Please see photos.

[BrokeColoReefer]

I have been expermenting with spacers, but all recieve the same result.
I think its because the material moves when you pull the pins. I dont think you can avoide that. Whats happening is the center of the joint is rock solid, but all the edges dont realy get a very good bond.

I have been expermenting with 2 kinds of pins.
1) 17 guage sewing needle
2) wire from the inside the coax cable for your tv, not the thick one, but the one around the insulation.

Results are the same with both pins, but the wire is MUCH cleaner. The pins were spilling out solvent down to my shims.
Here is my procedure.

1) rout the edges with a spiral upcut blade on a router table.
2) insert wire or pin
3) insert a bubble free bead of solvent. (weldon 4)
4) walk away
5) come back in five minutes and look in disgust at my joint. ( i work hard on getting my edges perfect)
6) i DONT put any pressure on the joint. I just let gravity take care of it.

My edge work is immaculate. I couldnt get it any cleaner if i wanted too. This problem must be common, EVERY joint i have made has this same characteristic, even with worse edge work (like strait from the table saw). It something im doing.

Please see photos, thanks for looking!!!
I have read tons on reefcentral and have not found this problem. If you know of a link please share.

http://i11.photobucket.com/albums/a168/BrokeColoReefer/IMG_5895.jpg

http://i11.photobucket.com/albums/a168/BrokeColoReefer/IMG_5896.jpg

http://i11.photobucket.com/albums/a168/BrokeColoReefer/IMG_5897.jpg


http://i11.photobucket.com/albums/a168/BrokeColoReefer/IMG_5899.jpg

http://i11.photobucket.com/albums/a168/BrokeColoReefer/IMG_5901.jpg
This one is of the edge that im making

http://i11.photobucket.com/albums/a168/BrokeColoReefer/IMG_5900.jpg
od course the coax wire is the smaller one.


Thank you for your help!!

[BrokeColoReefer]

Im getting better joints without the pins. My problem must be movement when i pull the pins out. I have let it cook for many different times. 30 sec 45 sec 1 minute. With the pins it can cook as long as a minute and a half and pins still come out easly and dont leave any marks. The wire can last any longer then 30-40 seconds. I do find that without the pins i will get a bubble here and there. With the pins i dont get any bubbles untill it starts to dry. Then the sides go haywire :(

I dont think its my edge work. You tell me.
http://i11.photobucket.com/albums/a168/BrokeColoReefer/acrylicedge.jpg

[calvin415]

Hey bro, I have the exact same problem when I try working with Weldon 4, and the best I can get is with wait time of about 3 minutes. Give it a try but I still end up with similar results in the end. I think it's just too dry here in Colorado and the solvent evaporates too quickly. I've had perfect results using weldon 3 though and waiting 40-45 seconds before pulling the pins.

[BrokeColoReefer]

I hear ya, but i thought that three was faster evaporating then 4, so is should work just the oppisit. I can tell you this, i have some three, unfortunalty its in my wifes car which is not here. It will have to wait till tonite for the test.

[calvin415]

3 dries faster but it also works faster so you don't end up with the bubbles... Works great IME but I try to stick to nano's... The hard part is if you're working on a larger tank you might not be able to get the top or bottom welded in 40-45 seconds so you need a second person to pull the pins...

[BrokeColoReefer]

Thanks alot!! i cant wait to try some three tonite. This 4 is driving me nuts, or my technique is....
I just did a four minute soak with #4 and its still wants to float away. Its by for the longes soak i have tried. I will post a photo if it turns out.

[BrokeColoReefer]

So far letting the #4 soak for three minutes has yeilded the best results, not perfect yet. I will keep working at it.

[calvin415]

Sweet, be sure to post pics of your results...

[BrokeColoReefer]

This is a three minute soak with number 4, not even close yet but better. I think i will go 2:30 next time.
Now the weight of the acrylic might help, what do you think? Or is a test run pretty indicative to the finial project?
http://i11.photobucket.com/albums/a168/BrokeColoReefer/IMG_5908.jpg

[BruiseAndy]

Try clamping it after you pull pins.

[BrokeColoReefer]

That wont be real praticle on a large piece. When i clamp it it does come out great. I can tell you this, the wife just got home and i got the weldon 3. 45 second saok and the joint looks promissing. If it turns out i will post the pics.

[BruiseAndy]

<a href=showthread.php?s=&postid=8539472#post8539472 target=_blank>Originally posted</a> by BrokeColoReefer
That wont be real praticle on a large piece. When i clamp it it does come out great. I can tell you this, the wife just got home and i got the weldon 3. 45 second saok and the joint looks promissing. If it turns out i will post the pics.

You could use pipe clamps. Being in the bbq and stove business I'm sure you can cut black iron to whatever size you need. I'm in utah and have the same humidity (or lack thereof) issues and it is the only way I've been able to attain bubble free joints.

[BrokeColoReefer]

I will try some pipe clamps, i was afraid they would be to heavy.

[stugray]

I use bags of shotgun shot to weigh my pieces down after the soak.

Stu

[BrokeColoReefer]

Made my first joint, used weldon 3 and the joint came out near perfect. :)

http://i11.photobucket.com/albums/a168/BrokeColoReefer/IMG_5912.jpg

[calvin415]

Good Job Bro!!! :)

[calvin415]

BTW, can you post a shot of your routerbit? I haven't heard of a spiral bit before and didn't see them when I hit Lowes last... I use a double flute and call it good.

[BrokeColoReefer]

Here is a link... we have them at work, but there more expensive then this.. i have never seen these go this cheap. There normally $70
http://www.amazon.com/CMT-191-506-11-Solid-Carbide-Upcut-Spiral/dp/B000K2FH2Y/sr=1-25/qid=1163530964/ref=sr_1_25/102-1128153-7152926?ie=UTF8&s=hi

Thanks for the tip Calvin with the weldon 3 , 4 was going to make me nuts.
Now i have to figure out how to use weldon 3 on the bottom. Gluing 4 sides down at once will be a challenge in under a minute.

[calvin415]

I assume you just setup your router table to work like a jointer? Looks like it works like a champ! :)

[BrokeColoReefer]

yea, pretty much set the fence to shave off less then a hair width. took the saw marks off with one pass. the edges shown above are raw off the router.

I have a jointer, but it didnt put nearly as good as finish as that bit did.