Cast Iron Bandsaw table no longer flat!

[Steliz]

I noticed that my bandsaw table is no longer flat across both sides of the gap for the blade.

It was definitely flat previously and I realised something was up when I was cutting some small items that 'rocked' over the gap.
As it's been a long hot summer I thought that maybe the table had warped a little so I slackened off the trunion bolts and left it for a couple of days to 'relax' but it is still the same. The difference is less than 0.5mm and will have minimum impact on what I do but I wondered if anyone else had encountered this.

 

[Rich C]

Cast iron is relatively soft, could it have been worn away?

 

[Bod]

Is there a small bolt that fits at the end of the slot?
This is fitted to even up both sides of the table.

Bod

 

[Steliz]

It hasn't had enough use to be wear and there is no bolt to align the sides or any indication that one is missing. Are these part of the casting or can it be retro fitted?

Judging by the responses it would seem to be just my saw then.

 

[Alpha-Dave]

The hole for the pin doesn’t look like a normal bolt hole, but should be 2 matching semi-circles in the casting where a single hole was drilled prior to the table being split. Zoom in to the pic in the link for an example location:
https://www.axminster.co.uk/axminster-c ... saw-105095

This is done because it is very common for cast iron to move when machined; firstly removing the ‘skin’ from casting (the bit in contact with the sand of the mould) allows stresses to be released, then cutting a line down the middle will certainly allow movement.

The surprising thing would not be that your table has moved but that there would be no built-in mitigation for this issue.

Do you have a zoomed out photo of the edge of the table?

 

[Steliz]

Hmm, I don't have that or anything else on mine (see pic). The bandsaw is about 12 years old so should be reasonably up to standards.

There are some tapped holes under the front edge but I think they are too far apart for a bolted on bar to correct the difference.

 

[Inspector]

Is that dip just at the edge of the table or is it all the way to the blade cut out circle area? If around the blade can the trunnion mounting bolts be shimmed a little to compensate? If it can I would start there. If it is just at the edge by your belly I would leave it unless it really is interfering with the cutting. There is material at the start of the slot for an alignment pin and you could, with the right equipment, drill the hole for the taper pin (not bolt) to keep the surface flat. As a last resort you could take the top to someone that can drill the edge for the pin and then surface grind the top flat. That is likely to cost you some and if it is not a good saw probably not worth the cost. Attached is a couple links to pictures of a hole and pin.

https://www.woodmagazine.com/tool-revie ... dsaw-table
https://www.google.com/search?q=band+sa ... 5&bih=1283

 

[Steliz]

The dip goes all the way from the front edge to the blade with a consistant difference and laterally from the gap to the mitre slot. The trunion mountings are behind the blade away from the area with the dip so they may have limited influence on the low section but it's worth a try anyway.

It's not really that much of an issue unless the piece I'm cutting is small, certainly not worth spending any money on but thanks for the suggestions.

 

[Ttrees]

I can move the split in the table on my bandsaw by a substantial amount.
If you've got a pair of nuts between the casting and the table, lock down the bolts that are attached to the table on the trunnion
and adjust with the other nut to push the table where you want.
A square needs to be behind the blade to keep the table 90 degrees also whilst doing this.

 

[no idea]

In your third photograph there is a hole under the table - is there a corresponding one on the other side of the slit and are they both threaded? If so, there should be a steel plate that bolts into these to bring both sides of the table into alignment.

If this a Record Power bandsaw you should be able to get a replacement from them.

 

[Steliz]

I have managed to dig out the manual for the bandsaw and it would appear that there should be a bolt at the front of the gap but, for whatever reason, mine doesn't have it.

 

[Ttrees]

I should have said I have a pair of nuts on each of the tour table threadbolts thats inbetween the trunnion and the table, and another four nuts to lock the
threadbolt on the trunnion.
If it turns out to be a problem for you regarding the table being higher, you could always grind down the nuts for a lower profile.
That misalignment is nothing compared to what mine is like if left to do its thing.