Thread: 100mm Hole in Bandsaw Door

A 100mm holesaw should do the trick, What thickness is the material to be cut?

Originally Posted by Metmachmad

A 100mm holesaw should do the trick, What thickness is the material to be cut?

+1..Just be sure to use a Bi-Metal hole saw..

Dremel? I don't know about this saw in particular but perhaps a better solution would be a shroud around the lower blade guides with an additional pick up?

Hi Chris,
Line of holes then cleanup with a half round file would be the way I would do it given minimal tools, holesaw would be next but needs to be a quality saw, then need to get your speed down sloooooow and good tourque as to drive a 100mm holesaw takes some grunt and hold the panel ridgid, clamped down or sqeezed between sheets of ply (or such) you would probably get away with a not so ridgid setup if the hole was right in the corner if near the edge folds, large holes in sheet can also be done in a radial arm drill or mill but would need a suitable made up tool for the job, if you don't want to mess about I'd take it to the sheetmetal blokes and they'd nip it out, might have to find one that will do it cold if you don't want to mess up the paint.


Pete

Hi Chris,
I don't quite get why you need a 100mm hole.
What about say 3 x 25mm. Holes, as surly that would be enough.
With a 100mm. hole, how could the D/E do it's job properly?

I have only ever sealed holes and added shrouding to improve extraction. Your plan seems counterproductive to me.

Greg

I will see if I can find a holesaw, the panel is most probably only 1.5mm thick or thereabouts. As to why I need to do it, this saw suffers the same disease as most, no make up air when the door is closed. It has a 100mm DE adapter just under the blade but when the door is closed there is no equivalent hole to allow air into the cavity and no air in = no air out. I am going to put it straight opposite the existing hole just under the table and the air will travel at high speed straight across and capture the dust when it first enters the cabinet still attached to the blade or that is the theory. Most bandsaws have no allowance for the make up air and this is the reason most DE is not effective on them and everyone tries to use external pickups. I did the same thing on my TS and it works really well keeping the cabinet fairly clear. The other approach would be to let the dust fall and put the pick up at the bottom and leave the original pick up to allow the air to enter the cabinet but I am not sure if that will work as once the dust has fallen it might start to build up in pockets in the cabinet, that will most probably either way but we will see. Thanks for the suggestions.

As issatree says. You don't really need a 100 mm hole, just the equivalent in holes. A whole bunch of little holes in a nice design perhaps.

TL, as good as that sounds I think a big hole will work better. Yes, small holes will let the air in but it will be "random", the best word I can think of. What I am after is a gale for want of a better word blowing straight across the blade to capture as much of the debris as possible. Admittedly this is a bit of an experiment to see if the idea works and you could be right but we all have to start somewhere. I should get an effect in the cabinet like this link shows happening with a mitre saw, actually pulling the air and debris to the pick up.....
Chop Saw Dust Collection with a Clearvue Cyclone - YouTube

I was also thinking why round? Was thinking of cutting a hole with a metal cutting blade in a jig saw to fit one of those plastic louvre type inserts for cupboard doors,but that dose not seem to fit in with your thinking. I would still think of some type of guard as the size and position of your intended hole could be inviting disaster if some little hands should wonder into your shed.
Regards

What about an air- or drill- powered nibbler?

Trepanning tool. The kind that goes in a drill. Like a flycutter with a drill in the centre.

I agree that BS are poorly ventilated and they suffer because they just don't get enough air.

What is critical is the air flow is as high as possible at the source of the dust making but it does not matter how the air gets there, ie large or small holes. This will still generate the "gale" that is needed at the blade.

However, if a number of 25 mm holes or a 100 mm hole with metal louvres across are used the number of holes needed to generate the air flow required will have to be about double the cross sectional area of one 100 mm dia hole.

The other approach would be to let the dust fall and put the pick up at the bottom and leave the original pick up to allow the air to enter the cabinet but I am not sure if that will work as once the dust has fallen it might start to build up in pockets in the cabinet, that will most probably either way but we will see.

My BS has a port just under the table and another in the base of the cabinet and it seems to work OK (ie dust does not pool) but it still could use more input air supply. My plan is to cut a square hole in the bottom door and add a large set of metal louvres so that more air is made available to both ports.

You can get metal cutting blades for jigsaws

Still think lots of little holes would work fine.