Bulkhead glass hole size

BlackTip · 02/10/2015, 09:08 AM

I asked GLA to drill 5 holes for 1.5" schedule 80 bulkheads, and I have to provide the dimension.

BRS have listed it as 64mm/2.51". Other retailers listing them as 2 5/8"/2.625".

After talking to BRS, they said that their bulkheads are generic brand.

What is the most common dimension I should go for? I want something standard, so it can be easily found for future maintenance. Any particular brand I should stick with?

The tank is 96X30X26. Internal overflow box. Bean style with 2 return lines/pumps.

Thanks,

insteng · 02/10/2015, 09:13 AM

I would drill them for the 2-5/8" size. You could always put the smaller ones in there with no problem but if you drill the holes too small you can't go use the slightly larger ones.

ca1ore · 02/10/2015, 09:25 AM

64 mm converts to 2.52 inches (well rounded to 2 decimal places). Discrepancy you note is just the calculation from metric. Nearest hole saw to 2.52 inches is 2 5/8. I'd go with the 64 mm hole myself; less slop.

BlackTip · 02/10/2015, 09:44 AM

Quote:

Originally Posted by ca1ore

64 mm converts to 2.52 inches (well rounded to 2 decimal places). Discrepancy you note is just the calculation from metric. Nearest hole saw to 2.52 inches is 2 5/8. I'd go with the 64 mm hole myself; less slop.

BRS recommends and sells 65mm for 1 1/2" bulkhead

02/10/2015, 09:08 AM	#1
BlackTip Registered Member Join Date: Jan 2015 Posts: 1,598	Bulkhead glass hole size I asked GLA to drill 5 holes for 1.5" schedule 80 bulkheads, and I have to provide the dimension. BRS have listed it as 64mm/2.51". Other retailers listing them as 2 5/8"/2.625". After talking to BRS, they said that their bulkheads are generic brand. What is the most common dimension I should go for? I want something standard, so it can be easily found for future maintenance. Any particular brand I should stick with? The tank is 96X30X26. Internal overflow box. Bean style with 2 return lines/pumps. Thanks,

02/10/2015, 09:25 AM	#3
ca1ore Grizzled & Cynical Join Date: Apr 2006 Location: Stamford, CT Posts: 17,319	64 mm converts to 2.52 inches (well rounded to 2 decimal places). Discrepancy you note is just the calculation from metric. Nearest hole saw to 2.52 inches is 2 5/8. I'd go with the 64 mm hole myself; less slop. __________________ Simon Got back into the hobby ..... planned to keep it simple ..... yeah, right ..... clearly I need a new plan! Pet peeve: anemones host clowns; clowns do not host anemones! Current Tank Info: 450 Reef; 120 refugium; 60 Frag Tank, 30 Introduction tank; multiple QTs

02/10/2015, 09:13 AM	#2
insteng Registered Member Join Date: Nov 2005 Posts: 42	I would drill them for the 2-5/8" size. You could always put the smaller ones in there with no problem but if you drill the holes too small you can't go use the slightly larger ones.