DIY- "Pins" method of gluing acrylic.

Hey Rich, how far away is Rochester from your area? I'll be there in a few weeks. I'll have to check out your club's site. Thanks!
 
If that's Rochester, NY. I'm about 460 miles or 7hrs away. Kinda far for a day trip. I live 10 miles north of the most southern tip of NJ (Cape May) so everything is far, far away it seems.
 
Ok can any one hear help me on this. I want to drill my 46g bowfront and put an overflow in it, the tank is acylic (what type I don't know) and I was going to make the overflow U section with routed teeth out of FFAcryLite acrylic. How should I attach the two together with Weldon or sillicone the tank I'm refering two can be seen hear http://reefcentral.com/forums/showthread.php?s=&postid=9876286#post9876286 I was going to put the over flow in the center of the tank. any thoughts and sugestions welcome.
 
HELP!?!

HELP!?!

I have been trying to assemble a sump and tank. I have been practicing on 1/4" for the sump and a smaller tank and have the joints nearly perfect. However, the time has come for the 3/8 on the main tank and try as I may, the joints all seem to keep getting bubbles in them as in the photos here.

jpndave

jpndave


This one is exaggerated a bit. Any of you experts have any suggestions.

It is 3/8 cast acrylic, Weld-On #4, 80 degrees, .22mm accupuncture needles, ~30 seconds soak.

Thanks for any help you can offer.
 
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The black piece should extend past the clear piece if possible.

Keep adding weldon, 2 or three passes. Its just evaporating too fast.

squirt a half inch above the clear piece.

We try to keep the temp under 75 and humidity under 40% and stable for 48 hours.

HTH
 
The black piece should extend past the clear piece if possible.

Not sure what you mean here. These pieces were just practice. The actual pieces would be flush on the ends and one of the two hanging past about 1/8 to be routed off, depending on whether it is for the front, sides, back or top/bottom. Is that right? I have been following James' instructions on his "DIY Tank (Dialup beware), Step by Step". Same bracing, camperfoam, routing, etc.

http://www.reefcentral.com/forums/showthread.php?s=&threadid=390652

Keep adding weldon, 2 or three passes. Its just evaporating too fast.

With the braces in place, I can only get at one side. I can continue to add to the outside but that probably won't solve it for the other.

squirt a half inch above the clear piece.

Not sure what you mean here either.

We try to keep the temp under 75 and humidity under 40% and stable for 48 hours.

Is there a way to slow things down other than temp? I can do it inside but even then it will be 78 or so with a lower humidity. The shop swings from maybe 75 to 85. I could do it early in the morning at the low temp.
 
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How is it whe you glue 3/8" clear to 3/8" clear? Often times, black and other (especially opaque) colors are "harder" and simply do not glue as well. This effect varies from mfr to mfr.
I'd reall advise folks to get clear mastered prior to doing colors. At least with clear, you can see what's going on and use this knowledge and experience when using colors.

When you were doing 1/4", what brand were you using?

Try not letting it soak so long. You should not have to reapply solvent like that, esp something as thin as 3/8". Should be a "one-shot" deal

Temp is fine, humidity is fine. No worries there.

FWIW, Chemcast is at the lower end of the totem pole IMO, try using the same techniques on Polycast, all clear at first to start :)
While I know how the Chemcast is made and in theory - should be fine, I don't know who their resin source is or if it's a consistent source, so material may vary from batch to batch and there may be variations from one thickness to another.

IMO (again) acrylic really is one of those things in which you gt what you pay for. The better materials just cost more, and quite worth it

HTH,
James
 
The 1/4" was the same stuff, chemcast. I wish I could go back now and get Polycast, oh well, hindsight, didn't know at the time. I thought I was getting the best making sure it was cell cast material. However, it is all purchased, cut and edged so I'd just as well try it out now. Somewhere I read adding Acetic acid to #4 helps. Or, in the other thread James mentioned his personal formula for solvent welding. What is your current take on that?

I'll try bonding clear to clear. I wasn't aware that colors were different. That is just what scraps I grabbed.

Thanks,

Dave
 
with the reformulation of WO-4, I can't say with certainty, I haven't played with the new formula at all. There are other solvents such as MCBond which are essentially methylene chloride and acetic acid (w/ a little monomer tossed in as filler of sorts), which is essentially what I use. In general, acetic acid slows the reaction down and helps the solvent flow a little better. 5-8% acid solution, tops. Just remember to get 99+%assayed acid, the photographic grade is usually 20% water and can screw up joints; don't ask me how I know this :(

HTH,
James
 
OK, I tried a sample of clear to clear letting it sit for 15 seconds and that was MUCH better. There are still noticible amounts of small bubbles on the sides of the joint. What can I do to eliminate those? Will the Acetic Acid help with that or maybe going to your custom mixture of solvents? (if so, where is the best place to source the Ethylene Dichloride? I can get the other two but the chem lab store doesn't carry the Ethylene Dichloride.) Maybe some weight on the joint? Longer or shorter soak times? More solvent initially? Less?

Thanks for the help.
 
Using a solvent like mine might help, but couldn't make any promises. I can't tell how good the edgework is, how flat or warped the material is, and a number of other variables so may not be of much help at this point, might just have to play around with it and see what works and what doesn't. That said, many companies are in the same boat as you presently are; can get it to be *almost* perfect, but not. If ya ever get such that's it's always perfect - I'll buy the book :)
Some states (OSHA) have pretty much completely banned the use of EDC so may be very difficult to obtain. My lab store won't "stock" it either, but will bring it in when I order it.
FWIW, I don't know much about the pin gauges, do you know what these things actually measure? The wires I use for 3/8" are .009" and .014" depending on application.

HTH,
James
 
First of all, I really appreciate your help with all of this James.

The material and joints are prepped as well as is possible. I have professional equipment as I build cabinets. Pieces were initially cut on a Sawstop table saw with a Dewalt professional Plastic blade then edged on a router, again professional table, with a shear angle bit, the edges and pieces are square and true. Equipment is here:

http://www.sawstop.com/products-cabinet-saw.htm

http://www.woodpeck.com/lsrspk3.html (With cabinet lower)

Shear Angle Flush Trim Router Bit here:

http://www.mlcswoodworking.com/shop...arthtml/pages/katbt3.htm#kt_shearangle_anchor

Pins are .22mm or about .009"

Would it help to add the Acetic Acid to the WO4? Can I add 5-8% to the WO4 I have?

The acid is the most expensive of the chemicals. 2.5L for $21.39 (smallest size they have and it is 99.7% pure if I remember correctly). The Methylene Chloride is $10.38 for 1L or $27.79 for 4L. Not sure of the cost on Ethylene Dichloride but they thought they could order it. I am in Utah so most EPA and OSHA stuff hasn't hit us yet. The store is at Utah State University which is 10 minutes away.

Surfaces are dead flat. There is a slight slope to the floor, maybe 1/2 to 1%. I coud shim that out if necessary but it has never been a problem and both uphill and downhill sides of the joints are the same.

Thanks again,

Dave
 
Not sure about the new formulations of the Weld-on products so can't say if and/or how much adding acid would help, but couldn't hurt :) The acid you note is fine. I'd add a little (5% or so) and see how it goes, at no time should you need to exceed 10% acid.
I'd just play around with it and see what works for solvents, soak times, etc. These are all variables that require a "feel" rather than technical advice IMO. Just practice and see what works. Wish I could say more than that.

I wouldn't be the least bit concerned about the floor slope.

FWIW, I haven't heard anything good about the reformulated WO products, in fact quite the contrary so really can't tell ya more than that regarding the WO-4. And you're working with a material that I have used but not extensively so really not sure I can help much at this point, hope you understand. Hopefully someone with more experience with this material will chime in.

James
 
With more experience than whom? James, you're our top dog! :D

Dave, you're using all the cool toys, and I'm very jealous. I've been watching this thread because I too suffer from those stupid bubbles.
 
Thanks James! I'll get some of the Acid and play a bit. I may go ahead and order the other parts and make up a "known quantity" to use as a glue.

Ya, Melev that saw is just awesome and the peace of mind doesn't hurt either. I like having all 10 fingers and want to keep it that way. I did have the saw trigger once (though not on my finger) and it was something else, one second the blade was there and the next is wasn't. Besides, it is the nicest saw I have ever used! The router table is nice too, I highly recommend both tools. Oh, and thanks go out to you too Melev as I have appreciated your site for the sump design and also enjoyed your articles on Manderins. I plan to have one someday :)

I am hesitant to "go for it" on the 3/8 as the first two joints are the most important. It had been very frustrating as the 1/4" worked so well. :furious:
 
What I do whenever I have a spot I don't like is to run a 1/8" bead of Weld-On #16 to act as an additional layer of protection.

How much did that saw cost you? I checked once and it was $2700.
 
The SawStop is a very nice saw. I haven't been able to take one "into battle", but I did get a good, close look at one at my local WoodCraft store. It definitely has much nicer features (not counting the saw stop itself!) than my trusty Grizzly 1023Z.

The only problem I have with SawStop is the inventory himself. When none of the companies would license his patented technology, he tried to get "sales" the other way: He went to DC and tried to get laws passed that would REQUIRE all tablesaws to include his (patented) technology!

It's always good when you can get the government to FORCE everyone to buy your product.

If safety was truly his only concern, he would have put the technology in the public domain first.

But anyway, this is WAY off topic! Sorry. Now for more important details on how to make good acrylic parts! This is especially relevant to me now as I am in the process of building my second DIY protein skimmer and I will be picking up a 4x8 sheet of cell cast Plexiglas on Friday to start work on my 48x16x16 skimmer!

Keep the good ideas flowing!
 
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