Help! Size of hole for a 1" bulkhead?

[whirley]

Hello.
I'm about to drill 3 holes into my tank, and wondering what size hole do I need to drill if I use a 1 inch bulkhead?

I'm assuming that I'd need a hole a little larger than the bulkhead? By 1/8" ?


Thanks for the info!
whirley

[pmcustom]

Maybe this will help: http://www.savko.com/portal/bulkhead.asp

[whirley]

So, If I use a 1" bulkhead, I have to drill a 1 3/4" hole? Seems like it's quite a big hole....*shurgs*

whirley

[pmcustom]

the 1" bulkhead in my aquarium (from savko, the lightweight version) needs about 1 3/4 minimum. i would get the bulkheads and measure them first though, before you start drilling holes!

[Typhon]

Yes.. most standard 1" bulkheads require 1 3/4" hole. Most of the bulkheads that I owe are from Savko and they use 1 3/4" holes..

[pmcustom]

and the threaded style are VERY easy to crack...at least the 3/4 are. if you can manage, i would go with the slip fit style :)

[Typhon]

I agree with "pmcustom". I have had 2 of the 3/4" crack on me already.

[pmcustom]

i ended up having to set everything in the bathtub and make adjustments, to see what tightness stopped the leak. also, i only used about 1 layer of teflon.

[whirley]

Cool.
I told the glass cutter to go with a 1 3/4" hole. Just seems wierd, that it's a whole 3/4" larger. But, that's what you guys have been saying as well as the website. I think the largest hole I can drill is 1 3/4", the glass cutter doesn't have anythhing bigger.

thanks again!
whirley

[Chris_Lee]

Are you guys using the Schedule 80 "heavy duty ones" or the lightweight ones. I am suprised you had a Heavy Duty one crack. I am about to buy 4 for the bottom of my 120 and I was thinking I had to buy the heavy duty ones. I was also going to buy the threaded ones for flexability in setup. Is a 3/4" bulk big enough for returns and overflows?

[xeon]

Well, I told my local glass shop the same thing... and they were doing it for $5, so I was pretty happy. Three and a half weeks later...hehe.. they finally drill the thing and the hole is like 2". My 1" bulkhead definitely fits and I had to be very careful in tightening it down, no leaks though. I should have driven to my reef shop an hour away and got it done for $10. Good luck, 1 3/4" is the right size for most 1" schedule 40 bulkheads.

[Typhon]

Chris_Lee.. they where the light weight versions. I have never really used the heavy duty version.

[xeon]

Originally posted by Chris_Lee
Is a 3/4" bulk big enough for returns and overflows?
Maybe for your return, but I'd want a bigger one on the overflows. I'd use 1" bulkheads at least, but what kind of flow are you aiming for? The bulkheads have limits in terms of flow rates.

[pmcustom]

i have a 1" drain and 3/4" return, 4' head and a mag1200 full open (some flow goes to the refugium). yes, the bulkheads are schedule 40, or the lightweight versions.

[Chris_Lee]

I am looking for pretty high flow. This is a 120g that is 24" tall so I am thinking I am going to need heavy duty Bulks. The tank came predrilled with 4 (1 3/4") holes and I am just trying to get all the plumming done. I am not sure what size return pump it came with but I would assume quite large. So it seams if I go with a heavy duty bulk I restrict my flow... but if I get a 1" bulk that is Schedule 40 I run a possible risk of it being weak???


I hate this crap.

[pmcustom]

no, not at all. schedule 40 just fine. scedule 80 prob has 1/4" wall thickness! overkill...

[Typhon]

Chris.. I cracked my sch 40 bulkheads by screwing in PVC fittings. Normally Sch 40 bulkheads will not crack. They must of been cheaply made. The bulkheads from "Premium Aquatics" have never cracked on me. They probably are carrying higher quality bulkheads. The ones from PA.. seem stronger..

[pmcustom]

i think the length of the threaded area is the problem...the 3/4 bulkheads from savko are prob twice as long as they need to be, and therefore weaker. in the future, i would cut them down first. i don't know what the PA parts look like though. also, this only applies to the 3/4 savko. the 1" are fine as far as i know.

[Sloth]

Originally posted by whirley
I told the glass cutter to go with a 1 3/4" hole. Just seems wierd, that it's a whole 3/4" larger. But, that's what you guys have been saying as well as the website.
Put a ruler up to your 1" bulkhead. 1" is the INSIDE diameter. Thats why the thing won't fit in a 1" hole.

[Typhon]

pmcustom.. thanks for the info.. I was going to stop ordering from them because of that issue too..

[Acrylics]

Originally posted by Chris_Lee
I am looking for pretty high flow. This is a 120g that is 24" tall so I am thinking I am going to need heavy duty Bulks. The tank came predrilled with 4 (1 3/4") holes and I am just trying to get all the plumming done. I am not sure what size return pump it came with but I would assume quite large. So it seams if I go with a heavy duty bulk I restrict my flow... but if I get a 1" bulk that is Schedule 40 I run a possible risk of it being weak???
So ya know, 1" Sch 80 bulkheads will not fit in a 1 3/4" hole so the decision in this regard is already made :). 1" Sch 80 bulkheads require a 1.9" hole. I usually use 1 15/16" for this size.

James

[Chris_Lee]

Do you recomend Sch 80 over the 40. A plumber here at my work told me to be sure to use 80. I dunno, I just want to do it right. So it comes down to me using the 40 and getting a 1" flow or using the 80 and getting the 3/4" flow.

It says I need a 1 5/8 hole for the heavy duty but I have a 1 3/4" is that to much play?

[Acrylics]

Originally posted by Chris_Lee
Do you recomend Sch 80 over the 40. I prefer the Sch 80 for a few reasons reasons; 1) thicker gasket, 2) thicker wall, 3) softer material - not prone to cracking, 4) thicker thread pattern - no crossthreading or strippng of threads. This said, Sch 40 will work for most applications, Sch 80 is stronger and is therefore my preference. I do agree with pmcustom though, that it is prolly overkill for most applications.

A plumber here at my work told me to be sure to use 80. I dunno, I just want to do it right. So it comes down to me using the 40 and getting a 1" flow or using the 80 and getting the 3/4" flow. Many folks have used Sch 40 and I feel they've "done it right". So that's kind of a subjective statement, and I don't know that using Sch 80 is always necessarily better either, just what I've always done as a practice.

It says I need a 1 5/8 hole for the heavy duty but I have a 1 3/4" is that to much play? Nope, I usually use a 1 11/16" hole for the 3/4" so another 1/16" won't hurt anything. BTW, the gaskets are 5/16" wide so you have a little room.

James

[Chris_Lee]

Thank you for clearing that up!!

The only thing I was worried about was that 3/4" would be too restrictive, but I am thinking it will be fine for the overflow and the return.

I will sleep better with the heavy duty because its a brand new house and my wife would KILL me if she came home to a flooded house. :eek2:

[whirley]

Chris_Lee,
Yah, I know the feeling about the wife with the shotgun.

I intentionally drilled an 'emergency overflow' hole, just incase.

whirley

[Chris_Lee]

How does it work?

[whirley]

I dunno..I just got the hole drilled this morning.

:-)

Geoff