For steel door manufacturers: how to prepare a 40 x 20 x 2 mm box profile for System One Slim, System Fx Slim and Top pivot Slim, how heavy the door can be, which gaps to keep and what to order.
Slim steel profiles have changed what an interior door can look like: glass from floor to ceiling, uninterrupted sightlines, frames cut back to the minimum. Conventional pivot hardware does not fit inside such a frame. System One Slim, System Fx Slim and Top pivot Slim do. They are 18 mm high, top and bottom, and sit inside the tube.
This article is for the steel door manufacturer. It covers the profile, the preparation in your workshop, fitting, how heavy your door can be, the gaps and what to order. The product figures come from the Slim profile preparation and mounting manuals.
The profile
The Slim pivots need a closed box profile of at least 40 x 20 mm with a 2 mm wall, which leaves 36 x 16 mm inside. In steel that is a common stock size: cold-formed welded hollow section to EN 10219, for example in grade S235JR, at 1.76 kg per metre.
The profile has to be closed. An open U profile is not suitable, and neither is a complex, thermally broken one.
Preparing the profile
The top and the bottom of the door take the same preparation, in the 40 mm face of the tube:
one cutout of 114 x 32.4 mm with four R4 corners
two holes of Ø6.2 mm, countersunk to Ø10.2 mm, 128 mm apart
Where the pivot axis can sit depends on how you make the corner of the frame. With a mitred corner, the axis is at least 70 mm from the end of the profile. With an overlap corner, it is at least 80 mm.
Each product page has the 2D drawing (DWG) and the 3D model (STEP) for your CAD and CAM, and the complete profile preparation and mounting manual.
Fitting in six steps
With ProfileFit, the pivot goes into the profile without adapters or extra parts. The steps are the same for both bottom pivots and for Top pivot Slim:
Prepare the cutout at the pivot position.
Guide the long side of the pivot body into the cutout.
Lower the body flat into the profile.
Slide the pivot to align it with the bolt holes.
Insert two M6 countersunk bolts.
Tighten both bolts to 8 Nm and check that the pivot is secure.
Watch the ProfileFit installation video:
Weight and door width
Both bottom pivots are Class C. How heavy the door can be depends on its width: the further the far edge of the door is from the pivot axis, the lower the limit. Every 100 mm costs 10 kg.
400 to 499 mm from the axis: up to 209 kg
600 to 699 mm: up to 189 kg
800 to 899 mm: up to 169 kg
1,000 to 1,099 mm: up to 149 kg
1,200 to 1,299 mm: up to 129 kg
1,500 to 1,599 mm: up to 99 kg
2,000 to 2,099 mm: up to 49 kg
2,200 to 2,299 mm: up to 29 kg
An example. A door 1,000 mm wide with the pivot axis at 70 mm has its far edge 930 mm from the axis, so it can weigh up to 159 kg. A perimeter frame of 40 x 20 x 2 mm tube for a door of 1,000 x 2,600 mm takes 7.2 m of tube, about 13 kg. The glass is most of the rest. The door weight calculator in the FritsJurgens Selector adds it up, and the Selector gives the definitive class for your door.
Gaps
Keep a top gap of 4 to 10 mm, so the pin of Top pivot Slim stays covered in the ceiling plate. A sagging floor or a ceiling that flexes changes that gap, so allow for it. The bottom gap is 11 mm.
On the pivot side, the seam depends on the door thickness and on the pivot position. For a door 40 mm thick, it is 5 mm with the axis at 70 mm, 4 mm at 100 mm, 3 mm at 250 mm and 2 mm from 500 mm. The Gap Calculator gives every gap of your door.
Draught seals, drop seals and latches can affect the last part of the closing movement. Take them into account when you specify the door.
Free swing or hold positions
Two bottom pivots, one question: does the door have to stay open in a position?
System One Slim swings freely through 360°, without hold positions. The door stops where you leave it.
System Fx Slim holds the door at 0°, 90°, 180° and 270° with a gentle holding force and swings freely in between. Within 10° of a hold position, the door is drawn into it. It is the first and only system with hold positions at 18 mm.
Both are operated by hand, and neither is self-closing. Both work double-acting, single-acting against a stop such as the frame, or revolving. For pivoting walls and room dividers, use System Fx Slim, and fit a clear, visible handle.
Floor plate and ceiling plate
System One Slim comes with the squared floor plate without adjustment. System Fx Slim comes with the squared floor plate with radial adjustment of +2.5° to -2.5°. Both floor plates and the ceiling plate come in stainless steel or black.
The floor plate and the ceiling plate are glued in place. Degrease the plate and apply a bead of about 1 mm. Use the FritsJurgens glue supplied, or a permanent elastic MS polymer glue, and nothing else.
What to order
The Slim products are sold as complete sets only. Each set holds the bottom pivot, Top pivot Slim, the floor plate, the ceiling plate and the mounting material, in one box. There are four sets:
ST.One.SL.C.SN.SS: System One Slim, stainless steel
ST.One.SL.C.SN.BK: System One Slim, black
ST.Fx.SL.C.S.SS: System Fx Slim, stainless steel
ST.Fx.SL.C.S.BK: System Fx Slim, black
The pivots need no maintenance or oiling. Clean them with a damp cloth and mild soap, never with aggressive cleaning products.
Heavier doors
For doors heavier than 209 kg, up to 500 kg, use the regular System One with Top pivot Reversed. That top pivot is mounted in the ceiling rather than with ProfileFit.
Downloads and next steps
The manual, the DWG and the STEP file are on the pages for System One Slim, System Fx Slim and Top pivot Slim. All three products are together on FritsJurgens for minimal profiles. To put your set together, use the FritsJurgens Selector.
