Record Power BS350S Trunnion Roller

[MikeK]

I just bought the BS350S bandsaw and am going through the setup process. I noticed the table moves slightly after it is locked down and think I have identified the cause of the wobble. The trunnion rides on a fixed shaft and the threaded locking shaft. I included some iPhone pictures showing the fixed shaft and have never seen this before. I would appreciate it if someone would tell me if this is normal for this saw.

This is the left side of the fixed shaft, as viewed from the front of the saw. The washer does not contact the trunion and this is as far as it will go into the trunion because of the flared end of the shaft.

This is the right side of the fixed shaft showing the locking nut and washer in contact with the trunion.

I removed the locking nut and washer to show how far the shaft goes into the trunnion.

This is the shaft removed showing the flared end.

If I tighten the lock nut to the point where the wobble goes away, I can't adjust the table tilt. I appreciate all comments and suggestions.

Mike

 

[MikeJhn]

Silly suggestion, but have you got the shaft in the right way around.

Mike

 

[MikeK]

It's not a silly question at all and I thought the same thing. The setup shown is how it arrived from the factory. In order to turn it around, I have to remove the table tilt adjustment knob by pushing out the rolled pin. The knob interferes with inserting the shaft from the right side.

 

[MikeJhn]

May be worth doing just to eliminate it as an option? In the manual it does show the bolt being on the tilting handle/gear side.

Mike

 

[MikeK]

Unless someone with the same bandsaw confirms this setup is correct, I will try to reverse the shaft this week.

 

[MikeJhn]

Have a look at page 17 fig 5.3 in the manual.

Mike

 

[MikeK]

My curiosity got me, so I removed the tilt adjust shaft (not the knob) and inserted the shaft from the right side. The shaft fits the same as when it's inserted from the left side. The flared end stops the shaft from passing completely through.

I suppose the shaft was inserted correctly from the factory, and a slight drag is as good as it gets. I snugged the locknut to the point where there is a balance between movement and the ability to turn the tilt adjust knob.

 

[MikeJhn]

Strange, I can't find that part on the exploded diagram on page 33 of the manual, part 124 looks like a plain bolt, but part 147 is nowhere to be seen and part 148 is missing from the description.

Suggest you get in touch with Record Power, perhaps they can shed some light on what is supposed to be there or how it fits.

Mike

 

[MikeK]

I think there is a lag between design changes and publication of the manual.

The rip fence carrier on page 13 of the manual is significantly different what was shipped with my saw. However, the exploded view on page 34 of the manual is correct.

The black plastic ends of the mitre fence on page 15 of the manual are reversed on the fence that came with my saw. I could reverse the locations, but don't see any need to do this now. The mitre assembly is not included in the exploded views or parts list.

Update: I contacted Record Power and sent a description of what I see, as well as directed them to this thread.

 

[MikeK]

I haven't heard back from Record Power, so I decided to make my own modification to the shaft and see how it worked.

The diameter of the flared shaft was about 12mm and the length was about 80mm, so I thought I would use an M12 carriage bolt with a washer and nut on the other end. Unfortunately, the square shank and the button head on the M12 were huge and I didn't think the shank would fit in the trunnion slot. Instead, I bought an M10 x 80mm carriage bolt, flat washer, and two nuts to try. I also bought a meter long section of aluminum tubing that has an outer diameter of 12mm and a wall thickness of 1mm. The M10 bolt fits nicely in the tube.

I cut the tubing to fit, and here are the parts laid out. I decided to use the longer nut because I will add a knob to it with a locking nut so I don't have to use a 13mm socket on an extension to loosen the nut.

This is how the assembly will look when installed in the trunnion.

After installing the new shaft, the square shank of the M10 bolt moves in the slot, but it doesn't completely rotate.

This is the view from the left side of the trunnion before adding the washer and nut. The aluminum tube does not extend beyond the trunnion side.

Because the square shank on the M10 bolt fits in the trunnion slot, the aluminum tube does not extend completely into the slot. My next version will use a regular M10 bolt and flat washer with a longer aluminum tube.

Here is the installed assembly. There is enough internal thread on the long nut to allow me to install a knob, assuming I can find or make one with the M10 thread and small enough to fit under the table. I put a little lithium grease in the slot to allow the trunnion to slide over the tubing easier. The grease made a positive difference, but I will be watching it to see how much dust it accumulates.

And now the results. After tightening the new nut, the table is rock solid. Any attempts to move the table in any direction causes the entire bandsaw to move. With the stock shaft, the same movements resulted in only the table moving. My cost for this fix was €6.27 (about £5.35), but I still have almost a meter of 12mm aluminum tube left.

 

[misterfish]

I assume the supplied post is actually meant to be flared - I was pondering the possibiity of bad machining and that it should be straight along its length.

Misterfish

 

[MikeK]

I assume the supplied post is actually meant to be flared - I was pondering the possibiity of bad machining and that it should be straight along its length.

Misterfish

This is what I thought and why I created this thread. I hoped someone with the BS350S would read this thread and check their bandsaw to see if it was the same and post the results here.

 

[delboy47]

misterfish wrote:
I assume the supplied post is actually meant to be flared - I was pondering the possibiity of bad machining and that it should be straight along its length.

My thought as well. I just cannot see what purpose a flare would serve other than jam the trunnion bar at one end when tightened up.

 

[MikeJhn]

Mike

Fig 6.10 on page 19 shows the locking handle shaft being inside the same slot as your troublesome shaft not as you have it assembled in your pics above? This could account for the poor locking you where experiencing.

Mike

 

[MikeK]

Mike,

I didn't show the locking shaft in my latest photos, but it is almost the same as shown in Figure 6.10. I'll take some photos in a few minutes and post them here.

 

[MikeK]

Here are two photos showing the trunnion. The first is from nearly the same angle as Figure 6.10 in the manual.

The alignment of the adjustment knob, table locking lever, and angle indicator on my machine are almost in a straight line with the locking lever closer to the edge of the trunnion base. In the manual, the locking lever is at the 6 o'clock and quite a bit away from the edge of the trunnion base.

The trunnion section that mounts to the table is considerably different than its counterpart shown in the manual. I suspect there are other undocumented changes as well. To illustrate yet another difference between the manual and the machine, Figure 6.10 does not show the two locking nuts on the shaft that controls the lower thrust bearing adjustment. In the image above, the two external locking nuts on the adjustment shaft are clearly seen.

This is a nearly straight on photo of the trunnion.

 

[MikeJhn]

Ah ha, my mistake I was looking at the thrust bearing shaft.

Mike

 

[MikeK]

I found a video, in German, on YouTube that shows the trunnion of the BS300E. It appears to be identical to the trunnion on my saw. The trunnion part starts at 5:04, and at 5:37 the video clearly shows the flared shaft extending from the left side of the trunnion base.

https://youtu.be/o3iZnR-YcBM?t=5m4s

 

[Robbo3]

Here is the installed assembly. There is enough internal thread on the long nut to allow me to install a knob, assuming I can find or make one with the M10 thread and small enough to fit under the table. I put a little lithium grease in the slot to allow the trunnion to slide over the tubing easier. The grease made a positive difference, but I will be watching it to see how much dust it accumulates.

Replace thread coupler with an M10 female Bristol locking lever - £3.53 from Axminster. You could probably source one closer to home.
- http://www.axminster.co.uk/axminster-lo ... s-ax864163

Edit: See you already have. Sure they weren't showing when I posted.

 

[Neil S]

I have the BS300E and the shaft does not look tapered on mine....
Hope these photos help.

-Neil