Framing/braces or just bolt the plywood together?

[Alexa]

I would like to build a cage or two over my spring break, and apparently have nothing better to do at school than plan enclosures and other snakey-things. The way I'm planning, the cages will be front opening, and between 3x1.5x1.5 and 3x2x2, and I'd also like them to be able to stack without the use of a shelving system. I'm planning on using some nice plywood (not OSB) and probably a marine epoxy or something similar to seal it. Though I have little experience building anything, I have a brother who is a master of everything power-tools, and with his help I should be able to manage :D

So my question(s): Do they need to have some kind of internal framing, perhaps made of 2x2s? Or is it sufficient to just screw the sheets of plywood together?

Any other suggestions are welcome, too!

[pdomensis]

I've done both ways. Framing is definitely more sturdy and safer to pick up and move around, and would be safer to stack like you mentioned. That said, I think if you went with a thick enough ply (like 5/8 or bigger) so screws can bite into it, they would stand up just fine. I've got a 3x2x2 here made of 1/2 inch ply with no framing. I can feel it flex a bit when I pick it up, but otherwise it works great.

[Alexa]

Thanks! I was originally planning on 3/4in ply, but I think if I end up doing a frame I might go with 1/2in just to cut down on the weight.

[kelzerman]

If your building that small of an enclosure I wouldn't bother framing it. You could just use 3/4 ply and it would be sturdy as hell. Just make sure to pre-drill that plywood so you don't split it. If you can look into a rabbet joint.


Here is everything in layman's terms:

Types of Wood Joints (http://www.docstoc.com/docs/86023230/Types-of-Wood-Joints)

[KORBIN5895]

If you put an interior framework in it doesn't look quite as nice but it will last forever.

[kelzerman]

Thanks! I was originally planning on 3/4in ply, but I think if I end up doing a frame I might go with 1/2in just to cut down on the weight.

Plywood is pretty light.. About 1.8 lb/ft2 for 3/4" pine plywood.

[kelzerman]

I will agree with korbin. With framing it will look like dog ****. If you have a brother who is good with power tools have him do rabbet joints on a table saw. After you glue and run a few screws in there it will be plenty good for what you need.

and actually if you want to take it a step further you could post laminate the exterior to hide all the screws and joints.

[Alexa]

This is why I ask these kinds of questions here :) Also, looking up rabbet joints is making me jealous of all of this woodworking. I really ought to take a class or something.

So would there be a rabbet joint at every single edge and corner, or just on the top and bottom, just on the sides, or what? With this stuff you kind of have to explain it to me like I'm five.

Thanks for all of the input from everyone!

[kelzerman]

Just one rabbet per joint. Example: the back is captured between the two sides so the sides would have the rabbet. You would apply glue in the joint. Then screw in from the back.

[kelzerman]

Oh I forgot to add if you decide to do the rabbet. Go about 9/16" deep that will leave you with 3/16" remaining. Now 3/4 plywood isn't really 3/4" it's a little shy. So it's more important to hold the remaining at 3/16" I can shoot you a drawing of an example. It sounds harder then it really is. To be honest if you decide to just do butt joints it will work just fine. The rabbet joint just is a little more structurally sound. If you have the equipment to do it then I would recommend that if not it's no big deal. For a cage that small you will be ok.

I'll send you a drawing of a 3'x2'x2' when I get some time.

[LarryS]

I agree with the previous suggestions. The more complicated joinery is better depending on the project.

However, if you only used butt joints with screws it would be plenty strong. It is only a box, with no working load so there will be very little stress on the joints. Adding the epoxy would make it even stronger and seal the joinery from moisture intrusion.

It is important to make all the cuts as square and straight as possible. Plan the project out thoroughly so all the pieces fit together in the best way possible.
As said above use a drill and countersink to pre drill the holes, carefully keeping them in the center of the material.

Generally speaking the more plies in the sheet the easier it will be to work with.

If you have access to sheet PVC rather than wood, it would make the job much easier.

[kelzerman]

I agree with the previous suggestions. The more complicated joinery is better depending on the project.

However, if you only used butt joints with screws it would be plenty strong. It is only a box, with no working load so there will be very little stress on the joints. Adding the epoxy would make it even stronger and seal the joinery from moisture intrusion.

It is important to make all the cuts as square and straight as possible. Plan the project out thoroughly so all the pieces fit together in the best way possible.
As said above use a drill and countersink to pre drill the holes, carefully keeping them in the center of the material.

Generally speaking the more plies in the sheet the easier it will be to work with.

If you have access to sheet PVC rather than wood, it would make the job much easier.


Correct PVC is the way to go. You are talking a major price difference. I am in the process of ordering a 4'x8'x1/2" PVC type 1 and it runs $160 a sheet. That is through our supplier at work.

[Alexa]

Thank you all so much! I was pretty sure that butt joints would work (even though I didn't know the word) but I want to do this the same way that I (try) to do everything with my pets: go a little overboard on the research before hand so that I have the best chance of ending up with something that I can actually enjoy.

I watched a couple of youtube videos on rabbet joints, and it looks like it would be pretty straight forward for someone who can actually operate a table saw. I really like the idea that these cages could be something that can last a long time, and will probably look better because of the extra effort. I'm also planning on eventually using some kind of bioactive substrate and I would like the cages to stack, so I am a little worried about what kind of load the different methods could handle.

PVC probably would be a great way to go, but it seems like for what it would cost I could just about buy a PVC cage from Animal Plastics! Which is also an awesome way to go, but I'm going to try building my own for now.

[mclund]

Correct PVC is the way to go. You are talking a major price difference. I am in the process of ordering a 4'x8'x1/2" PVC type 1 and it runs $160 a sheet. That is through our supplier at work.

That's a bit pricey. Larry and I can buy it for 75.00 a sheet if we order 10 sheets at a time. Even buying a single sheet is less than 100. It's still more than plywood, but worth the extra IMO.


Matt

[formica]

$160 per sheet is extortionate for PVCX :o

contact the head office of which ever brand of PVC you are using, directly, and ask them to put you in contact with your local distributor, you will save allot by using their distributor, the more companies there are between your supplier and the manufacturer, the bigger mark up you have to deal with


as for loading - aluminium profiles will deal with most load issues, anything from a simple angle to hold 20~30kg distributed, or a type6 20x40 profile which will hold a distributed load in excess of 50kg without bending (best to use the manufacturers calculations, my numbers come from my manufacturer and may not be the same for yours)

Highly recommend PVC, if you are comfortable working with wood, you will find it great to work with...and being able to pickup a 4ft enclosure with hardly any effort is really something, makes cleaning and transport much less of a chore :)

you can build a PVC enclosure in exactly the same way you would with plywood, except for different glues, and slower cutting/drilling speeds - or you can get creative and use other techniques which are impossible with wood, but provide a beautiful finish, simple or as complex as you like

[LarryS]

Kelzerman mentioned type 1 PVC.

Gonna Google it, must be something different.

[kelzerman]

That's a bit pricey. Larry and I can buy it for 75.00 a sheet if we order 10 sheets at a time. Even buying a single sheet is less than 100. It's still more than plywood, but worth the extra IMO.


Matt


Who is your local distributor? What kind of pvc are you guys using? I have never heard of PVCX.

I am going through my local distributor and for a 4'x8'x1/2" sheet of Type 1 he is charging 163. I am assuming there is a major grade/spec difference. It is sabics plastic in Madison heights Michigan.

[LarryS]

We haven't purchased from them but I've had good quotes on materials.

Piedmont Plastics - Plastic Sheet, Plastic Rod, Plastic Tubing - Quote today! (http://www.piedmontplastics.com/locations.aspx)

[mclund]

Kelzerman mentioned type 1 PVC.

Gonna Google it, must be something different.

Oops I missed that. Type 1 is stronger. PVCX is what we are using. So I have to ask Kelzerman, What made you decide on type 1?

Matt

[kelzerman]

Oops I missed that. Type 1 is stronger. PVCX is what we are using. So I have to ask Kelzerman, What made you decide on type 1?

Matt

I went with Type 1 because it more more impact, chemical, and corrosive resistance. We do use PVCX here at the shop. I have never heard it called that. Here it is known as sintra. PVCX is actually more like an expanded foam core. I also noticed that it does not hold up to impact very well. And actually PVCX is lacking Polyvinyl Chloride. Unless we are not talking of the same thing.

[formica]

I went with Type 1 because it more more impact, chemical, and corrosive resistance. We do use PVCX here at the shop. I have never heard it called that. Here it is known as sintra. PVCX is actually more like an expanded foam core. I also noticed that it does not hold up to impact very well. And actually PVCX is lacking Polyvinyl Chloride. Unless we are not talking of the same thing.

Sintra is PVCX, Polyvinyl Chloride = PVC, its still PVC, just expanded

Yep standard PVC is different to expanded PVC

the expanded PVC I use (PALRAM) will take a heavy mallet blow without any damage, not a very scientific way to describing it admittedly lol

[mclund]

The expanded PVC is not solid, but it has held up well for all our applications. I called our supplier and they quoted me 200. on the type 1, so 163. is a very good price. I would have to imagine never having worked with it, that the type 1 is as heavy as plywood as it is solid PVC.

Celtek is what we are currently using.

Matt

[mclund]

Alexa-Sorry for hijacking your thread. I hope this was as educational for you as it was for me.

[kelzerman]

The expanded PVC is not solid, but it has held up well for all our applications. I called our supplier and they quoted me 200. on the type 1, so 163. is a very good price. I would have to imagine that the type 1 is as heavy as plywood as it is solid PVC. I think the PVCX may be a trade name from one of the manufacturers.

I am looking for a more structurally sound application. With the type 1 I wont have as much deflection then the expanded pvc. Another plus is that it can be drilled and tapped. Which I doubt I would need to do.

Yes type 1 at 1/2" thick is 3.8 lb/ft2 and your typical 3/4" pine plywood is 1.8 lb/ft2.

Would you be comfortable standing on one of your cages? And do you house any large constrictors in a 6'-8' cage without worries?

[mclund]

I am looking for a more structurally sound application. With the type 1 I wont have as much deflection then the expanded pvc. Another plus is that it can be drilled and tapped. Which I doubt I would need to do.

Yes type 1 at 1/2" thick is 3.8 lb/ft2 and your typical 3/4" pine plywood is 1.8 lb/ft2.

Would you be comfortable standing on one of your cages? And do you house any large constrictors in a 6'-8' cage without worries?

I have to admit, I wouldn't want to stand on them, but I have kept a couple 6' boas in them with confidence. I wasn't being critical, sorry if I came off that way. I was just inquiring.

Matt

[kelzerman]

I have to admit, I wouldn't want to stand on them, but I have kept a couple 6' boas in them with confidence. I wasn't being critical, sorry if I came off that way. I was just inquiring.

Matt


Oh no not at all. I hope I didn't come off as a smart***. The particular one I am going to be building will be a permanent home for my female retic which as of right now is a baby.

I might take and build her a 4' enclosure out of the expanded pvc after hearing you.

I do want her final enclosure to be structurally sound. So, I will be using Type 1 on that. I can not have her getting out at that size.

Thanks for all the info!

[formica]

Yes type 1 at 1/2" thick is 3.8 lb/ft2 and your typical 3/4" pine plywood is 1.8 lb/ft2.

Would you be comfortable standing on one of your cages? And do you house any large constrictors in a 6'-8' cage without worries?


wow thats heavy stuff! interested to see how it comes out! weight is a significant factor in deflection, how rigid is it/what force can it withstand? thats how you will no for sure that it wont bend...

I would be willing to stand on a 2x1.2x1.2 made from PVCX, I would not stand on top of a 4x2x2 unless it was reinforced with Type6 profiles, but then again I would not stand on top of a Plywood, MDF or OSB unit made with the same thickness material

the PVCX that I use, is comparable in strength to MDF

[LarryS]

Placing weight on top of the cage is not going to test the deflection of the material toward the center of the panel unless you stood with your feet together in the center. I'd have no problem standing on any of the above mentioned cages with my feet over the vertical sides.

If these large snakes are able to expand their coils against the sides of the cage then I think the size of the enclosure would be a huge factor as well no?

I would be most concerned with the door, and the hardware that is used to attach it to the cage body. I sure as heck wouldn't use glass.

Is there instance of these guys breaking cages by expanding?

[kelzerman]

Placing weight on top of the cage is not going to test the deflection of the material toward the center of the panel unless you stood with your feet together in the center. I'd have no problem standing on any of the above mentioned cages with my feet over the vertical sides.

If these large snakes are able to expand their coils against the sides of the cage then I think the size of the enclosure would be a huge factor as well no?

I would be most concerned with the door, and the hardware that is used to attach it to the cage body. I sure as heck wouldn't use glass.

Is there instance of these guys breaking cages by expanding?


That's what I said. I would be worried about the size of the enclosure. A larger enclosure with expanded PVC would in my mind be very flimsy. I agree the door and hardware has been one of my biggest concerns. I would have no problem using 3/8" tempered glass. It is some strong stuff. On the surface of course. Tempered glass's weakness is the edges.

I am not sure if there has been instances, but think of the strength these constrictors have. Expanded PVC is not structurally sound. It has tremendous deflection. Think of the flex in a 4'x8' sheet. I would not take a chance with a large constrictor. Would be a nice test though if we could do this in a controlled environment.

For a smaller snake and a smaller cage I won't argue with you. With a front frame I'm sure it would hold up.

As far as standing with your feet together or over the side; I would want to test at its weakest point. Which would be the center. That is where you would get your most deflection. I'm not worried about testing this theory on strongest part of the cage.

Formica, I will get the specs on it, but I know it is substituted for solid aluminum.

[KORBIN5895]

Snakes and incredibly strong when they constrict their muscles. Not so much when they stretch them.

[kelzerman]

Formica I have not found any reliable data comparing type 1 pvc to expanded foam core. Only way to get reliable data would be to test it myself and I do not have the resources to do that. All I can say is we use type 1 for structural products that withstand high impact and weight. We also work with expanded foam core which is used for signage. I will tell you what expanded core is probably about 50% lighter... a 48"x22"x22" cage out of type 1 is about 113 lbs according to my software. Now I don't have a sheet of pvc to compare to this picture, but I can assure you that you will not bend a sheet of type 1 anything like this. Now this is a sheet that is 41"x60"x1/4"

http://farm8.staticflickr.com/7379/11980657633_1d8055a8bc_s.jpg (http://www.flickr.com/photos/51129064@N02/11980657633/)


http://farm3.staticflickr.com/2813/11980747414_30e183a627_s.jpg (http://www.flickr.com/photos/51129064@N02/11980747414/)


You know after looking into this a little more; you obviously have not had an issue with using 1/2" expanded closed cell. I respect what you guys do and in no way are bashing. You guys have made some fantastic looking cages, but I would not use it for a larger enclosure. I would however try using it for a little 3'x2'x2'

[formica]

certainly a simple sheet of PVCX is very flexible, but how much the structure of an enclosure bends, depends on allot more than that, not saying that Type I wont be significantly stronger or more rigid, just that there is more to the engineering/architecture of an enclosure, than the flexibility of a simple sheet, but of course yes it plays an important role.

but with good design, PVCX is structurally sound even to 4x2x2, although I personally would not build it bigger than that, some enclosure fabricators do and it seems to have damaged their reputation somewhat, with enclosures cracking and breaking

I would only stack max 3 units fully loaded with bio-active substrate, and only if they where fully reinforced with an internal frames, even with an internal frame the enclosure is lighter than a Plywood or OSB of similar size, if the right products are choosen



Look forward to seeing your finished results anyways! always interesting to see different materials being used - particularly interested as I have a 10X6 build coming up, where PVCX is definitely not an option except for finishing

[kelzerman]

certainly a simple sheet of PVCX is very flexible, but how much the structure of an enclosure bends, depends on allot more than that, not saying that Type I wont be significantly stronger or more rigid, just that there is more to the engineering/architecture of an enclosure, than the flexibility of a simple sheet, but of course yes it plays an important role.

but with good design, PVCX is structurally sound even to 4x2x2, although I personally would not build it bigger than that, some enclosure fabricators do and it seems to have damaged their reputation somewhat, with enclosures cracking and breaking

I would only stack max 3 units fully loaded with bio-active substrate, and only if they where fully reinforced with an internal frames, even with an internal frame the enclosure is lighter than a Plywood or OSB of similar size, if the right products are choosen



Look forward to seeing your finished results anyways! always interesting to see different materials being used - particularly interested as I have a 10X6 build coming up, where PVCX is definitely not an option except for finishing


Oh I agree completely! The structure it self will have a huge impact on the strength of the enclosure. I was just referring to the deflection of the material in its self... You will certainly not have that drastic of a flex in a correctly engineered enclosure. This project is a little down the road. I have to still order the type 1 and then working it into the production schedule of cncs. This will be all cut with high precision cnc machining. I will be sure to post pics of the outcome.

Me personally would think you would run out of floor to ceiling space before I would worry about the structure of the type 1 enclosures...BUT!! I have not had one of these enclosures in my hands yet so I very well could change my mind.

Formica,
Do you work for Formica brand laminate?

[formica]

haha no...Formica is a genus of ants :) my other ''exotic animal'' hobby

[mclund]

Lots of great information here guys. Larry and I talked about an oversized cage (8x2x2). I have this burning desire to keep an O Hannah, but that project is a ways down the road.

[kelzerman]

Lots of great information here guys. Larry and I talked about an oversized cage (8x2x2). I have this burning desire to keep an O Hannah, but that project is a ways down the road.


Right finally a nice un-heated debate full of useful information!

[LarryS]

A cage, as a structure is much stronger than the individual panels that make it up. I personally would not have a problem with a 1/2" pvcx cage at 8w x 4h x 3d, so long as the design is sound. The bottom would need to be fully supported, and the door and opening would be a challenge.
Having an animal inside that could expand against the cage body is an entirely different situation and I agree with everyone that pvcx would not be sufficient without additional reinforcement.

Matt, you're going to need a bigger snake room.

[Danimal]

For the OP, A simple, strong joint to make is with a good glue and pocket holes. I use gorrilla glue or liquid nails and a kreg jig. Lots of videos out there about it.

[guyabano]

With 3/4 in. plywood, you can make pretty good enclosures without additional support. Anything over 6x3x3, I'd start adding some framing. Good wood glue is your friend.

[Toggsy]

For the OP, A simple, strong joint to make is with a good glue and pocket holes. I use gorrilla glue or liquid nails and a kreg jig. Lots of videos out there about it.
Tbh I didn't know what a kreg joint was until I looked it up on the internet And in all fairness I thought it might of been another name for a biscuit joint.
This method looks real easy to do.
Are the jigs very expensive ?

[LarryS]

Tbh I didn't know what a kreg joint was until I looked it up on the internet And in all fairness I thought it might of been another name for a biscuit joint.
This method looks real easy to do.
Are the jigs very expensive ?

There are a lot of different versions of pocket hole jigs. I would recommend the type with the built in clamp like this;

Kreg Jig K4 Pocket Hole System - Amazon.com (http://www.amazon.com/Kreg-K4-Pocket-Hole-System/dp/B001DYFISG/ref=sr_1_2?s=hi&ie=UTF8&qid=1391910135&sr=1-2&keywords=kreg+jig)

I have an old Kreg jig and use it all the time. It's one of those tools that once you have it you wonder how you got along without it.

We have never used pocket holes for cage construction, but it is certainly an option. I personally still feel a simple butt joint is all that is needed.