Acrylic aquarium / Weldon 40 / bevels advice

[Yehudayardeni]

Hi all!! Been spending good 20+ hours researching this topic. I bought a square acrylic tank second hand. Dimensions 36x36x25H - 1/2 inch thickness. I added about 15 gallons of water for water test, and tank sprang couple leaks from front and side seam at the bottom.
So I emptied tank, bought Weldon 40 , applicator and .25in bevels to fit across all bottom seams and height seams (inside tank bevels). I’m getting lost on order of things. Tank has been cleaned and dried, also using compressed air to get all material out of from all seams. Should I sand 600 grit all seams and space under bevels then Weldon 40 the bevels? Or Weldon 40 first, let dry, then add bevels ? Thank you in advance !

forgot to mention last question! Clamps, should I use ? Light pressure ?

 

[Eelkeeper301]

wednesday13

 

[Yehudayardeni]

wednesday13

Thank you for tagging! I’ll add I bought 23/32 plywood to make sure I’m working on level as possible. Purchase shims to straighten as well!

 

[wednesday13]

Hi all!! Been spending good 20+ hours researching this topic. I bought a square acrylic tank second hand. Dimensions 36x36x25H - 1/2 inch thickness. I added about 15 gallons of water for water test, and tank sprang couple leaks from front and side seam at the bottom.
So I emptied tank, bought Weldon 40 , applicator and .25in bevels to fit across all bottom seams and height seams (inside tank bevels). I’m getting lost on order of things. Tank has been cleaned and dried, also using compressed air to get all material out of from all seams. Should I sand 600 grit all seams and space under bevels then Weldon 40 the bevels? Or Weldon 40 first, let dry, then add bevels ? Thank you in advance !

forgot to mention last question! Clamps, should I use ? Light pressure ?

Any pics of the applicator or materials ie. Bevels u plan to use? Weld on 40 is a 2 part epoxy. It would need to be measured mixed in small batches for each seam ur working on one at a time. Lay down some 40 and place ur stock rod/bevels over top. You can tape them in place with masking tape. You dont want to use clamps or anything. It can be applied up to a 1/4” gap so loose with tape is perfect. You also only have around 10-15 per batch mix of 40 to work so plan out ur steps and again work on 1 seam at a time.

the 40 alone can be made into a bevel by tipping the tank at 45 degree angles and pouring 1/4-1/2” across the seams… it self levels. Its a syrup consistency.

just want to make sure u dont have #4 solvent with a needle aplicator. Thats a different process all together.

 

[Yehudayardeni]

Any pics of the applicator or materials ie. Bevels u plan to use? Weld on 40 is a 2 part epoxy. It would need to be measured mixed in small batches for each seam ur working on one at a time. Lay down some 40 and place ur stock rod/bevels over top. You can tape them in place with masking tape. You dont want to use clamps or anything. It can be applied up to a 1/4” gap so loose with tape is perfect. You also only have around 10-15 per batch mix of 40 to work so plan out ur steps and again work on 1 seam at a time.

the 40 alone can be made into a bevel by tipping the tank at 45 degree angles and pouring 1/4-1/2” across the seams… it self levels. Its a syrup consistency.

just want to make sure u dont have #4 solvent with a needle aplicator. Thats a different process all together.

First thank you for rhat!! Makes it so much easier. When you say seam do you mean internally and external at same time , that’s 1 seam, or each seam should take 1 day?
Don’t mind hazing externally, I bought novus, will sand and polish after application. My concern with the tipping the tank method is my back. I currently don’t have anyone to help. I have piece of plywood between stand and tank , maybe I can add shims for more angle ?
View attachment IMG_0625.jpegView attachment IMG_0626.jpegView attachment IMG_0624.jpeg

 

[wednesday13]

First thank you for rhat!! Makes it so much easier. When you say seam do you mean internally and external at same time , that’s 1 seam, or each seam should take 1 day?
Don’t mind hazing externally, I bought novus, will sand and polish after application. My concern with the tipping the tank method is my back. I currently don’t have anyone to help. I have piece of plywood between stand and tank , maybe I can add shims for more angle ?
View attachment 1536648View attachment 1536649View attachment 1536650

thanks for the pics … “applicator” threw me off and i was right lol… that applicator is for weld on #3 or #4 solvent. You wont need it and cant use it for #40.
When talking about seams, i mean internally. All the work will be done on the inside unless what u do ends up failing, then we can talk about patching the outer seams lol… u shouldnt have to go there tho. 40 is a great product and super strong and fairly easy to use.
As for prep, you are correct, scuff up the surfaces that will be behind the rod/bevels with 200 grit paper. Clean with nail polish remover WITHOUT acetone or u can use alcohol.

mix ur 40 in batches around 50-100ml per seam, pour it out of a mixing cup directly onto the tank and slap ur rod/bevel piece down over top. Tape it in place. The glue will set up in 10-15 minutes depending on ur humidity, temps and altitude. You can move onto the next seam/piece in around 30-45 min.
40 is runny, its like syrup… it does not stay put. Its going to be a bit of a guessing game to get the correct amount behind the piece of rod ur putting in. It can be messy. Any glue that hits the acrylic will need to be sanded/buffed off or just left there. If you need to do any vertical seams this could be problematic but will work if u can calculate the right amount of glue to use as it will run right down if you use too much. Ur looking for full coverage behind the rod pieces. It will become clear when u press down by hand and apply tape to keep it there.
most definitely do the bottom seams first to get the hang of the process and figure out how much glue to use. If you can tip the tank to work on the seams you need flat, go for it. Ive done verticals with rod tho also on tanks i could not flip alone.

now for the downside of #40… its pretty toxic… the fumes can be very bad when ur using alot. Wear a good respirator… eat a Tylenol before u use it even lol… its best used in a well ventilated area. Use fans, open windows. Remove ur family from the house for a day if u need too. Ive gone as far as taping up plastic in a room to work in. You can also kinda trap the smell inside the tank with lids or a blanked if ur ventilation is poor. I used around a gallon one time in 12-14 hrs… my wife almost left me … every window was open in the house and it took a cple days to clear out.

if you have children, pets… and poor ventilation you can use the rod/bevels u have , that needle applicator and weld on #4 to pretty much accomplish the same thing. Each method has its pros and cons. Solvent is a bit more of a skill to do correctly but theres little to no fumes compared to 40.

 

[Yehudayardeni]

thanks for the pics … “applicator” threw me off and i was right lol… that applicator is for weld on #3 or #4 solvent. You wont need it and cant use it for #40.
When talking about seams, i mean internally. All the work will be done on the inside unless what u do ends up failing, then we can talk about patching the outer seams lol… u shouldnt have to go there tho. 40 is a great product and super strong and fairly easy to use.
As for prep, you are correct, scuff up the surfaces that will be behind the rod/bevels with 200 grit paper. Clean with nail polish remover WITHOUT acetone or u can use alcohol.

mix ur 40 in batches around 50-100ml per seam, pour it out of a mixing cup directly onto the tank and slap ur rod/bevel piece down over top. Tape it in place. The glue will set up in 10-15 minutes depending on ur humidity, temps and altitude. You can move onto the next seam/piece in around 30-45 min.
40 is runny, its like syrup… it does not stay put. Its going to be a bit of a guessing game to get the correct amount behind the piece of rod ur putting in. It can be messy. Any glue that hits the acrylic will need to be sanded/buffed off or just left there. If you need to do any vertical seams this could be problematic but will work if u can calculate the right amount of glue to use as it will run right down if you use too much. Ur looking for full coverage behind the rod pieces. It will become clear when u press down by hand and apply tape to keep it there.
most definitely do the bottom seams first to get the hang of the process and figure out how much glue to use. If you can tip the tank to work on the seams you need flat, go for it. Ive done verticals with rod tho also on tanks i could not flip alone.

now for the downside of #40… its pretty toxic… the fumes can be very bad when ur using alot. Wear a good respirator… eat a Tylenol before u use it even lol… its best used in a well ventilated area. Use fans, open windows. Remove ur family from the house for a day if u need too. Ive gone as far as taping up plastic in a room to work in. You can also kinda trap the smell inside the tank with lids or a blanked if ur ventilation is poor. I used around a gallon one time in 12-14 hrs… my wife almost left me … every window was open in the house and it took a cple days to clear out.

if you have children, pets… and poor ventilation you can use the rod/bevels u have , that needle applicator and weld on #4 to pretty much accomplish the same thing. Each method has its pros and cons. Solvent is a bit more of a skill to do correctly but theres little to no fumes compared to 40.

Thank you a million. Ok, I’m just concerned that the tank many not be 100%, and per research #4 feels more temporary for my concerns, as a family man and a tenant I don’t want to take risks for their health or for my landlords home, with that in mind, my office is in corner room of house which has two large windows and a ton of air flowing , I can open also my bedroom windows which is next door. I bought respirator for this, I’ll do small test and mix for 1 seam, if fumes are overpowering with ventilation and fan running , maybe Ill try setting up Dexter (show)style environment around tank with large plastic trash bags cut up and hole directly pointing at window lol, unless there’s an easier way.
P.s. my wife is killing me already for doing all this lol )

 

[wednesday13]

Thank you a million. Ok, I’m just concerned that the tank many not be 100%, and per research #4 feels more temporary for my concerns, as a family man and a tenant I don’t want to take risks for their health or for my landlords home, with that in mind, my office is in corner room of house which has two large windows and a ton of air flowing , I can open also my bedroom windows which is next door. I bought respirator for this, I’ll do small test and mix for 1 seam, if fumes are overpowering with ventilation and fan running , maybe Ill try setting up Dexter (show)style environment around tank with large plastic trash bags cut up and hole directly pointing at window lol, unless there’s an easier way.
P.s. my wife is killing me already for doing all this lol )

Sounds like u got a good plan… u should b fine. 50-100ml at a time isnt too bad at all to work/deal with. Ive mixed up entire pints at once and thats another story … you can use a digital scale to weigh out or also measuring spoons.

 

[Yehudayardeni]

Hey ! wednesday13 , after beveling bottom seams , with Weldon 40 and .25in bevels, the front seam in the outside in the front seems to be slightly split, and seems to be “moist” after adding 30 gallons of water, then side seams starting dropping slowly. I’m thinking of emptying and applying Weldon 40 on inside seams vertically, before I do so, will this tank ever be safe ? I have concerns, and I don’t want any issues , what do you think? If you need more pictures , happy to provide !! Thank you.

forgot to mention. I Weldon 4 all seams externally , after laying the Weldon 40, and waited 3 days before adding any water. I added external bevels across all vertical seams. With Weldon 4 and sanding before placing. I have to say I’m super annoyed with seller , he’s ignored me, won’t answer calls and messages , been weeks. Invested so many hours and monies argh

 

[wednesday13]

Hey ! wednesday13 , after beveling bottom seams , with Weldon 40 and .25in bevels, the front seam in the outside in the front seems to be slightly split, and seems to be “moist” after adding 30 gallons of water, then side seams starting dropping slowly. I’m thinking of emptying and applying Weldon 40 on inside seams vertically, before I do so, will this tank ever be safe ? I have concerns, and I don’t want any issues , what do you think? If you need more pictures , happy to provide !! Thank you.

forgot to mention. I Weldon 4 all seams externally , after laying the Weldon 40, and waited 3 days before adding any water. I added external bevels across all vertical seams. With Weldon 4 and sanding before placing. I have to say I’m super annoyed with seller , he’s ignored me, won’t answer calls and messages , been weeks. Invested so many hours and monies argh

Are you sure you got the bottom seams thick enough? 40 adheres to itself very well. You can always go 1/2-3/4” with ur inner bevels of 40. Id probably start with the inner vertical seams first if ur seeing it drip right out of there. Acrylic can always be fixed/ re in forced. I put back together a 450 that exploded in a guys house … personally i do bevels around 3/4” and ive done up to 1”. Theres no way water is getting through that. If ur tank is that bad it can be made new again with large inner bevels.

you might have been counter productive with the #4 solvent. Its pretty hard to re do solvent work. It can weaken the seams again if theres no pressure holding ur panels in place as it melts the acrylic.

regardless of that, the 40 can always go right over top of old work to reinforce it. Pour bevels of 3/8”-1/2” on those upright seams. If the bottom still leaks. Go over top of ur 1/4” for 1/2” as well. That should do it.