---
catalog: WEB-I3
catalog_name: Insulating Glass Fabrication Supplies
page: 16
sku_count: 2
skus:
  - "1G877"
  - "RB9"
bases:
  - "1G877"
  - "RB9"
generated_at: "2026-05-21T23:30:08Z"
---

# Insulating Glass Fabrication Supplies -- Page 16

This page features 2 products:

`1G877`, `RB9`

## Page Content

FHC INSULATING GLASS FABRICATION, SUPPLIES, AND EQUIPMENT
SECTION 2
FHC IG Fabrication Methods
THE GLAZING SUPPLY COMPANY
E X P E R I E N C E  A N D  I N N O V A T I O N
IG14
Bulk Quantities Available
Click to Chat With Us
IG Kits
Visit fhc-usa.com to search for
Enter the Item Number or scan QR code with  
your smartphone for complete product details
Sealant Application for 
Single Sealed Unit
Clamping Units:
Ensure that glass units  
are clamped on all sides to  
ensure a tight seal. You can  
use Spring Clamps with  
vinyl-coated jaws for this purpose.
When sealing multiple units, you can stack 
them using wood blocks as separators. 
Start with the largest unit at the bottom. 
Position the separators about 1" from the 
edges and 4" from the ends.
For smaller double-hung window sizes 
where all units are the same size, place a 
large piece of paper between each unit to 
prevent contact.
FHC IG877 Silicone Foam and 
Metal Spacer I.G. Sealant
FHC Item No. 1G877 Sealant does not 
require mixing and is ready to dispense 
directly from the cartridge.
Bulk Gun Application:
If you’re using a bulk gun, load the sealant 
into the gun and apply it to the edges of 
the unit.
Ensure that enough sealant is applied to 
penetrate into the shoulders of the spacer 
to create a proper seal.
Avoid using so much sealant that it 
displaces the spacer. Focus on applying 
extra sealant to the corners, which are the 
most vulnerable areas of the unit.
Hand Application of Two-Part Sealants:
If applying sealants by hand, use a putty 
knife to apply the sealant to the edges, 
following the same precautions.
FHC IG877 Sealant Application:
Apply FHC IG877 Sealant using a 
caulking gun (See Page IG38) and a 
sealant guide tip (See Page IG30).
After curing, remove excess sealant 
using a razor blade (Item No. RB9).
Ensure that the sealant has completely 
filled the back-set and is flush with the 
glass edges.
Check for Newton Ring:
Inspect the bottom units of the stack 
for a “Newton Ring” effect in the 
center of the unit. This occurs when 
two pieces of glass are in contact.
If you observe a Newton Ring, flip 
the affected units upright and repair 
them before transport to prevent 
permanent rub marks.
Following these steps will help ensure 
a proper seal and the longevity of 
your insulating glass units using 
FHC sealant.
Glass Panels
Desiccant
Spacer
Secondary 
Sealant
Primary Sealant 
(PIB)
Pane Interspace
(Filled with Gas)
Sealant to Flush 
to the Edge of 
the Glass