Y Merge Cutting Block | 1.5D & 2D Bends, 1.5"–4.5"

Y merge cutting block for 1.5D and 2D mandrel bends

Makes a Y piece from two mandrel bends of the same size. The block marks both cuts each bend needs: the long merge cut, which lets the two bends close into one round outlet, and the trim cut, which sets the angle of the Y.

The merge cut runs along the centreline of the outlet, so the two half outlets make one round outlet the same size as the tube. One block marks both bends.

Which version do I need?

This listing covers 1.5D and 2D bends. Pick your tube size, then the bend radius. 1.5D means the centreline radius of the bend is 1.5 times the tube's outside diameter, and 2D is twice (the table below gives both in millimetres). For tight 1D bends there is a separate 1D block.

These blocks are sized for OD tube: mandrel bends sold by their outside diameter. They don't suit SCH10S weld elbows, which are made to a different bend radius.

How it works

Push the key into the slot for the angle you want. The finished Y angle is twice the angle on the scale.
Lay the bend in the bottom half with its end against the key, then drop the top half on.
Scribe along the edge of the merge face where it meets the tube, on the top half and on the bottom half. That line is the lengthwise merge cut.
Mark round the bend at the end face of the block, or cut flush to the face. That is the trim cut.
Mark the second bend the same way. Turned over, it becomes the mirror half.
Cut both bends on the lines and bring the two cut faces together to form the Y.

Specification

Trim angles: every 5° from 45° to 80°
Y angle: twice the scale angle, as marked on the block. The 45° slot gives a 90° Y.
Outlet: one round outlet, the same size as the tube
Bend radius: 1.5D or 2D, chosen when you order
Halves: two, held together by magnets and lined up by locating pins
Angle key: included. It stores in the block when not in use.
Markings: black angle scale and size label
Material: plastic
Made: to order in our UK workshop

Sizes

Size	Tube OD	1.5D bend radius (CLR)	2D bend radius (CLR)
1.5"	38.1 mm	57.2 mm	76.2 mm
1.75"	44.45 mm	66.7 mm	88.9 mm
2"	50.8 mm	76.2 mm	101.6 mm
2.25"	57.15 mm	85.7 mm	114.3 mm
2.5"	63.5 mm	95.3 mm	127 mm
2.75"	69.85 mm	104.8 mm	139.7 mm
3"	76.2 mm	114.3 mm	152.4 mm
3.5"	88.9 mm	133.4 mm	177.8 mm
4"	101.6 mm	152.4 mm	—
4.5"	114.3 mm	171.5 mm	—