Acrylic fabrication questions? I can help!

[Acrylics]

Jimnrose,
The cut of a power saw is (IMO) "okay" at best, I personally would glue a sawcut edge, all edges are machined smooth on the router table. That said, folks do glue sawcut edges and the joints certainly can last a while, just generally don't look as nice as one that was machined first.

RC1214B,
Couldn't tell ya, never even tried.

Sandman,
Chicken has the good idea above. You could also try a hole saw.

Chicken,
Never saw that you were in San Ramon, I am down in your area from time to time; wish I'd known - I was there a coupla weeks ago, could have brought you some syringes. Oh well, next time

HTH,
James

 

[zxknight]

I know this question must have been ask many of time but were do you order your acrylic sheets from??

 

[chicken]

James no problem. Thanks for the offer though. You are more than welcome to crash my shop anytime you are down this way. Let me know. Thanks Chris

 

[jimnrose]

Acrylics, thaks for taking the time to share your knowledge.
Jim

 

[sandman12]

I don't have a template bit, can I get this at home depot? and what will it be labeled

 

[chicken]

Home Depot should have a flush trim bit which you can make work. They might have a pattern bit but if they don't check online to see if you have a Rockler or Woodcraft store near you. They will have one for sure.

The difference between a pattern bit and a flush trim bit is where the bearing is. A flush trim bit will typically be a 1/2" diameter bit (can have a 1/4" or 1/2" shank, if your router supports 1/2" shank go that route as you will get a cleaner cut because of less vibration) with a bearing on the top of it. An example would be
http://www.woodcraft.com/product.aspx?ProductID=144138&FamilyID=4655

With the flush trim bit the wood template you create would need to be below the acrylic you are routing. Say if you are making an oval that is 4" wide x 2" I would take a 1" hole saw and cut a hole in the middle of the acrylic where you want the oval to be. This will allow you to start routing out the oval without worrying about a catch on the router bit and ruining your project. From there I would double stick tape the template to the bottom of the acrylic and then fasten the whole thing down with a clamp to a workbench of table.

An example of a flush trim bit is at
http://www.woodcraft.com/product.aspx?ProductID=129640&FamilyID=1862

The difference here is that the bearing that rides on the template is in the middle so it would be close to the router base. This way you can double stick tape the template to the top of the acrylic and route it that way. You just need to make sure you have some sort of sacrificial wood below the acrylic as you want to make sure you just the entire width of the acrylic and not ruin your work bench below.

I have a router table so I can use a flush trim bit easy but its not that much harder with a hand held router. Check out my DIY Sulfur Denitrator build thread and you can see how I use a template to flush trim some 1/2 holes through some rigid PVC. Pretty much the same idea of what you will be doing.

Good luck and let me know if you have any questions.

-Chris

 

[ADA33]

What is the best way to cut 1/2" multiple holes in 1/8" acrylic.
I have tried various drill bits with my drill press but none seem to work really nice. Also if you can point me to a link to buy one that would help also.

Thank you in advance

 

[RokleM]

Forstner bit

 

[aldiaz33]

How to strengthen/repair an ugly seam

How to strengthen/repair an ugly seam

I purchased a used 240G with .5" Polycast cell cast acrylic all around. There are a few areas where the seams look cloudy/white. It appears that there may even be some separation of the acrylic sheets in these areas. Below is a photo.

Is it possible to reinforce the seams by inserting weld on into these cloudy areas? If so, what type of weld on should I use? On another online forum I read that trying to "fix" seams in this way may actually weaken the existing bond? Is this a myth?

Thanks in advance for your time.

Alex

 

[Borge]

Re: How to strengthen/repair an ugly seam

Re: How to strengthen/repair an ugly seam

<a href=showthread.php?s=&postid=13802990#post13802990 target=_blank>Originally posted</a> by aldiaz33
I purchased a used 240G with .5" Polycast cell cast acrylic all around. There are a few areas where the seams look cloudy/white. It appears that there may even be some separation of the acrylic sheets in these areas. Below is a photo.

Is it possible to reinforce the seams by inserting weld on into these cloudy areas? If so, what type of weld on should I use? On another online forum I read that trying to "fix" seams in this way may actually weaken the existing bond? Is this a myth?

Thanks in advance for your time.

Alex

.5 therein lies the reason i would guess. That is thin for such a large tank whatever meassures on the tank

 

[melev]

What is that area specifically? A gap? Is if filled with salt creep? Is it a cloudy spot?

 

[chicken]

Best bet might be a 1/2" router bit in a router. The problem with a drill is it just does not spin fast enough and tends to grab so it can easily crack the 1/8" acrylic.

<a href=showthread.php?s=&postid=13786024#post13786024 target=_blank>Originally posted</a> by ADA33
What is the best way to cut 1/2" multiple holes in 1/8" acrylic.
I have tried various drill bits with my drill press but none seem to work really nice. Also if you can point me to a link to buy one that would help also.

Thank you in advance

 

[troylee]

dull your drillbits in concrete first then drill your holes works like a champ.............just my 2cents........

 

[aldiaz33]

<a href=showthread.php?s=&postid=13803717#post13803717 target=_blank>Originally posted</a> by melev
What is that area specifically? A gap? Is if filled with salt creep? Is it a cloudy spot?

The worst of it is on the seam where the front sheet of acrylic meets the top sheet of the aquarium. The picture was taken standing over the tank looking down onto the top of the aquarium. I think there may be some space or separation between the two sheets where the seam is white/cloudy. I believe the previous owner had it set up with African cichlids, so I don't know if salt creep is an issue here. I think that applying some weld on might reinforce the seam, but I was hoping to get some feedback before giving it a shot.

Thanks again for your time.

 

[jimnrose]

ANOTHER question: how can I bend a 1/8" sheet of acrylic (acrylite) that is 24" long? I can build a fixture to define the shape but what temperature is required & can I use a hair dryer? [I'm building an overflow box but need to flare out the top (weir) to allow for access into the box because the tank has a 3" eurobrace along width just above the box] Jim

 

[melev]

Aldiaz, I don't want to steer you wrong. For now, what I would suggest is you take something very thin (paper, accupuncture needle) and see if you can insert it into what you think is a gab. If you can, then you could fill it with Weld-on #3 and let it cure again.

Of course, if James posts something different, ignore everything I typed.


jimnrose - you can heat and bend 1/8" acrylic easily, but you need a propane torch (like they use to sweat copper fittings). Never leave the heat in one spot. Always keep it moving, and it would be preferable to be able to heat it from either side. If you have a way to make a wooden form that holds the sheet from both sides, line the top edges with tin foil to deflect some of that heat from the torch. As it softens, you'll be able to bend it gently to the position you like. It will cool off over the next minute or so, and then you can remove it from the make-shift template.

 

[jimnrose]

Melev, thanks for the input. I'm sure the wooden form can be made. The challenge is designing it so the intended bend line is exposed to the flame on both sides. As I'm typing, I think I'm ready to put pencil to paper. Thanks.

 

[melev]

You'll heat the area right above the form & foil, and it will fold right over. If you have an extra board, use it to press down on the bend to get a nice 90 degree.

Just don't press too hard too fast. The acrylic will bend when it is heated enough.

Practice on some scrap.

 

[jimnrose]

Melev, thanks for the clear instructions. I got the wood forms layed out & belong to a great wood shop to generate some sawdust. Take care, Jim

 

[scotty1234]

Getting ready to heat bend some acrylic structures using a heat gun, is there any material that would provide a better mold to bend them around aside from wood?