Acrylic fabrication questions? I can help!

[peppie]

Floyd, OMG I didnt expect to have to mix any solvent, The material is Plexiglass-G. I did some test pieces with #3 and the #25 applic. And # 17 pins. the seans looked good I had a nice fillet on both sides.
Thanks for your reply Floyd. I will not weld any main part untill I hear from James
Thanks again

 

[Floyd R Turbo]

Sorry I thought you were using Polycast for some reason. I think with Plex-G you will be fine, sounds like you are doing it right. If you got a good bubble free seam and a nice fillet that's what you want. Hope I didn't freak you out. I just remember reading that WO products are good, but lots of fillers to comply with California codes, so if you're going to be building a lot of things, mixing your own then becomes an option. WO#3 will do fine as long as you work at the right pace and are comfortable using the product. I have used WO #3 with extruded and some Plex-G but much thinner material, and not for aquarium use.

 

[peppie]

It seems that if I wait between 30 -45 seconds then pull the pins I dont get as much splash out from the seam. I assume I dont want the splash as it would starve the joint of glue. Can or dare I wait longer.

Ive been reading you are going to build a large router table. You can use regular wood glue to bond the two pieces of mdf. I would rough up the mating surfaces with 150 grit sandpaper. Use a foam paint roller to spread the glue to both pieces. Clamp them together and screw it tight.
There are alot of good under mount router systems on the market. IMO the type that is adjustable from the top of the table would be the way to go. If one of the units is set in from the edges quite far it may be a pain to adjust the depth. I understand $ is always a concern but you must think about the long term use of a tool.
The thinner the plate that you can use to mount the router the better, but as you said if you go to thin it will defleck.
Hopr this helps. Thanks for your reply

 

[madmike]

FYI, James does not use router plates in his tables that I have seen, he has multiple routers always mounted with different bits for different situations... I'm not sure how he mounted his bases but I'm pretty sure they are permanent.

I used contact cement to bond the two pieces of MDF together, seemed to work just fine.

 

[Floyd R Turbo]

madmike, he is the one that told me to get a 3/4" aluminum plate and I think he does use that, I remember his posts about it. But he puts the plate in the top piece of MDF (also 3/4") and then lays the formica over the top so you don't see it. But it's definitely there.

 

[madmike]

oh, I didn't know that.... knowing that james works on some very thick stuff though I guess it makes sense. I have never used a plate but only have worked with up to about 1" thick and never had a problem with any flexing, after all you are normally only taking a very small amount off of the edges when prepping the pieces.

 

[Floyd R Turbo]

Mike, that's exactly the answer I was looking for. I think I am perfectly safe to make the table without a mounting plate, using 2 x 3/4" MDF for the top.

I have been going back and forth with building a 2x6 & 2x4 leg stand versus having someone make one. Prices for 3" square steel stand I was told $400-$700. 1"x2" was still $300 or so. So I think since I won't be making any 500 lb aquariums any time soon, it's going to be a wooden stand.

Peppie: thanks for the tip on the glue (mainly spreading with a roller). I think for the 'clamping' I will have to figure something out. I don't currently have clamps that can hold 2 pieces of 4'x6' MDF together. I do have a garage floor and 23 home depot buckets. I'm thinking I can fill these all with water (and put lids on) then put a 4x8 sheet of chipboard on the floor, 2x MDF on that, chipboard on the MDF, and set buckets on that. I think I should be able to get about 18-20 5g buckets or about 100 gallons, or 800 pounds on it. That should do the trick.

 

[Acrylics]

not so much about the cutters/routers flexing, more to keep the mounts permanent. Wood compresses, and wood screws can strip out.
Never said you could do the table like mine for $300, just that you can built better than anything on the market for that.

2 sheets MDF - $45-50?
Polished Formica - $60
wood frame - cheap as well
fences - whatever you have laying around

Peppie, I wouldn't wait that long, at least no more than what you are presently doing I'm one of those that sees no purpose in waiting too long and it can be problematic - esp for fast solvents like #3. I don't use pins at all, just stripped twist-ties, which is what I've always used and work well - they're about .014" and work well for materials above 3/8". As for "splash" - not sure what you're referring to - I don't ever see that. And for applicator bottles, I use the pink tipped one, but these are harder to use than the thin ones until you are well practiced. Sorry I can't be more specific, I'm on holiday and am not at the shop to verify anything

FWIW, I wouldn't use #3 for 3/4" material, it simply sets too fast for large joints IMO/IME

krshlln300, 1/4" should be fine based on what you are saying about the bracing you plan to use, just use good material

James

 

[Floyd R Turbo]

Allright peeps...what do you think of my layout for a router table?

The circles are the locations of cutouts in the lower MDF piece for mounting a router base. For a start, the center and right ones will have bases in them, the left one was one I contemplated so it's a 'future' location. As I keep looking at it, I don't see a need. The right position is good for trimming, edge prep, etc and can handle pieces over 5' in length (5'10" from center of bit to opposite corner, so there's room to get a fence in there). The center position would be for flush trimming and could also be used for all other purposes for smaller things (36" of less)

I might move the center one a little closer to one of the longer sides so that it's easier to reach. However I don't know if this would make a hill of beans of difference, having it 18" from one edge versus 24" from each? Or maybe also setting it 3" or so to the right so that I could use it for 36" pieces while having a fence all along the left side, instead of angled across the corner.

The framing shown will be 2x6s that will have one side ripped flat and true for the MDF to lay on, then 4x4 posts for legs. Not shown is the casing on the outside of the posts (like the DIY tank stand) and leg bracing just off the floor, and any cross bracing needed so it stays square and sturdy.

Hope this isn't all off topic too much. Seems a good place to put it since this will be built for acrylic fabrication.

 

[txmike2]

i would say to move them in from edge a bit .you will use the one on the right most of the time i would say 12" in from edge .

 

[Floyd R Turbo]

I should clarify, because it's a little difficult to see, but the right location is already 12" from the corner. Here I turned the grid off

Also planning on boxing around the base cutouts, that's not shown. As well as cross-members between the 36" runs to keep them from bowing.

 

[txmike2]

now i see .I would make table with no hole put a nail in about the location you want the router set up a rip and see how it feels running the sheet in .I think my set back on mine is about 18" from edge but at 6'6" I like the setback .

 

[TheFishMan65]

The right position is good for trimming, edge prep, etc and can handle pieces over 5' in length (5'10" from center of bit to opposite corner, so there's room to get a fence in there). The center position would be for flush trimming and could also be used for all other purposes for smaller things (36" of less)

I have never used a big router table (so bear with me), but I don't understand this. If you start to clean the edge of something 5 feet long you will get three feet into it and the over hang will try and flip it up.

Seems to me like you only need one hole. Centered on the long side and as close to the edge as possible. This will let you route a board as long as the table without tipping.

Why have one in the center? Are you going to use the router to cut down the center? What will rest on the other half of the table? Seems like you are trying to use the router as a table saw.

 

[Floyd R Turbo]

I have never used a big router table (so bear with me), but I don't understand this. If you start to clean the edge of something 5 feet long you will get three feet into it and the over hang will try and flip it up.

That's a good point. The center one would be used for smaller pieces, like 24" square or maybe 36" long. Small things that can be spun around to do each side for the flush cutting.

The left hole would then come into play for trimming and flush cutting longer pieces, feed from left, full 5'+ on the back side.

Seems to me like you only need one hole. Centered on the long side and as close to the edge as possible. This will let you route a board as long as the table without tipping.

That is true, for edge prep. Would probably work just as good as the left hole. I'm trying to picture this all in my head too. I threw the center one in there because it made sense for smaller items to have the item on the table all the time. I don't see myself making anything over 48" in the near future. By then I'll probably have figured out the pitfalls of whatever I make now, and will make a bigger table (to the chagrin of the wife, I'm sure)

Why have one in the center? Are you going to use the router to cut down the center? What will rest on the other half of the table? Seems like you are trying to use the router as a table saw.

For flush cutting as described above. I have a table saw so I wouldn't use it for center cutting nooooo. Not following the 'rest of the table' question. But this table will double for doing solvent welding also if that is what you are asking.

 

[peppie]

James ,
Thanks for the reply. I know your recommendations are based on you exp. I wish I had all the advised material to do this build correctly. But I only have #3 to work with. I will reinforce the corners and bottom seams with a 1/2''strip. It may not look professional, but I am hoping it will hold water.
Thanks again.

 

[Floyd R Turbo]

Router Table - Positions

Router Table - Positions

After much mulling, I could use a little input from those that have used a router table for acrylic projects. I'm trying to pin down the best 2 locations for a router. These are my proposed selections:

The table is 6' x 4' and the hash-mark lines are the 12" intervals.

Here is a list of what I would see as the use/benefit/detriment to each position:

Position #1: Feed from right side. Edge Prep and flush trim. Would be able to feed long pieces, but would need long fence.

Position #2: Feed from right or front. Edge Prep and flush trim. Would be limited in width when feeding from right and would need long fence.

Position #3: Feed from front. Edge Prep and flush trim. Would be able to trim pieces to widths of over 4 feet, but I don't see needing this that much since the front/back panels of tanks would just get flush trimmed, and I don't see building a tank with a large depth. Fence would be shorter (front to back).

Position #4: For flush trimming mainly, but could be used for edge prep. Would be nice for flush trimming because the tank/box could sit completely on the table & be spun. This is becoming one of my preferred positions. I'm thinking that I should move it 6" to the front (18" from front, 24" from right)

Position #5: Same as #4, but would not be as diverse of use, since it would have 36" on each side to the R/L versus 48" on one and 24" on the other.

Right now I'm leaning towards #4 (shifted 6" to the front) and #3. #1 is a close 3rd place.

To cover the "depends on what you plan on using it for" question, I can tell you the limit. I do not plan on making anything requiring greater than 3/4" material, unless it would be a rimless tank. That is, nothing over 6 feet long (and likely not much over 4 feet long). The largest thing I see myself making is something on the order of a 75 gallon sump if that gives you an idea.

So all you acrylic router table experts, what do you recommend? Other locations? What works for you and what do you use it for?

 

[txmike2]

my vote would be #2 and #5

 

[TheFishMan65]

No expert but I would not do 4 and 3. Especially 4 shifted forward and 3. At least if you are using a router plate. Given a 12x12 plate positions 4 and 3 would maybe touch (4 shifted would) and I think this would weaken the table too much (maybe not since you still have the bottom MDF). I would lean toward 4 shifted and 1.

Still confused??

Position #1: Feed from right side. Edge Prep and flush trim. Would be able to feed long pieces, but would need long fence.

How can you do a long piece (6 feet). Assuming a feed parallel to a table edge unless you are holding the acrylic at the start of finish I don't see how you can do it. Feeding fom the right you start with 5 feet off the table. Feeding from the bottom you start with 4 feet off the table. What am I missing? That is why I like 5. You can get 3 feet of the acrylic on the table which would allow for almost a 6 foot tank. Move it forward and you have 3 x 3feet for flush cutting spinning.

 

[Floyd R Turbo]

No expert but I would not do 4 and 3. Especially 4 shifted forward and 3. At least if you are using a router plate. Given a 12x12 plate positions 4 and 3 would maybe touch (4 shifted would) and I think this would weaken the table too much (maybe not since you still have the bottom MDF). I would lean toward 4 shifted and 1.

The plates don't necessarily have to be square to the edges of the table. Two 12"x12" plates at a 45 degree angle relative to the edges of the table would not touch. But good point. I don't think they would weaken the table, seeing as not using them at all has been suggested and would probably work fine.

Still confused??

How can you do a long piece (6 feet). Assuming a feed parallel to a table edge unless you are holding the acrylic at the start of finish I don't see how you can do it. Feeding fom the right you start with 5 feet off the table. Feeding from the bottom you start with 4 feet off the table. What am I missing? That is why I like 5. You can get 3 feet of the acrylic on the table which would allow for almost a 6 foot tank. Move it forward and you have 3 x 3feet for flush cutting spinning.

For #1 you would stand on the right side of the table. You would probably have to have another table, person, or a couple rollers to support the weight of the uncut side, but a 48" long piece would be workable, 5' or 6' would be more difficult but wouldn't need to be done as often. I'm thinking that 90% of what I plan on doing will be 30" a side or less.

 

[Floyd R Turbo]

my vote would be #2 and #5

Any reason in particular, and do you have/use a table with this configuration?