Thread: Table insert not flat

Hi John
I looked at that saw some time ago ... nice compact saw.

Does the insert have lug nuts that have to be adjusted?

Anyways ... you will probably want to make a ZCI at an early date.

Regards

Rob

Hi Rob,

There are grub screws in the recess in the table, one near each corner, to adjust the height. But it's the upper surface of the insert itself that is warped.
WP_20170810_001.jpg

I put it face down on blocks on a surface plate and found that each side is convex (longitudinally) by about 0.74mm. I then installed it on the table and used a digital height gauge. This shows that it distorts slightly under the force of the locating lugs at the rear and spring clip at the front. (The front (left end in the picture) comes about 0.2mm below the surface of the table, and the back about the same amount above the surface. But mid-length both sides of the insert stand about 1mm proud of the table. ISTM they should be flush with it at this point.

A ZCI is on the list of things to make. I haven't done one before and shall have to do some research into materials etc. At the corners - where it sits on the height adjusting grub screws - the cast alloy factory insert is only 2.7mm thick, and the grub screws are only 3mm diameter, so I suspect it'll involve more than just cutting and routing something from 8mm marine ply.

Apart from the warped insert, so far - i.e. without having actually cut anything with it - the GTS 10 J seems OK. The table appears flat and contrary to some reviews the sliding part is at the same level as the rest. Workshop space is too limited for a "real" table saw, and I have a home-made track saw with 1400 and 2400mm tracks for when I need to break down a big sheet, so the "compact" model should suit me fine.

Regards,
John

Hi John
Apart from getting an exchange part from Bosch you could heat it in a warm oven and reform it (if it is plastic) .... or sit the ends on, say 10mm blocks, and use a clamp from under the table to push the middle down if it were metal.

What a bugger though

Regards

Hi John,

is it actually an issue? As in if you put light pressure on the insert will it just flatten out? If so when you're running boards/panels through the saw it should be fine.

I would also adjust the insert so both are at the table level rather than having the rear higher, this may reduce the severity of the issue.

It's cast alloy, powdercoated or similar. The edges are only 2.7mm thick but there are reinforcing webs that take total thickness to about 12mm. If I don't get any joy from Bosch I might try straightening it as you suggest (or rather straightening each of the two sides, as they are only joined at one end.

Originally Posted by tonzeyd

Hi John,

is it actually an issue? As in if you put light pressure on the insert will it just flatten out? If so when you're running boards/panels through the saw it should be fine.

No, it would need a lot of pressure to flatten it.

I would also adjust the insert so both are at the table level rather than having the rear higher, this may reduce the severity of the issue.

That would still leave it more than 0.5mm proud at the centre, okay for casual work but not satisfying.

I understand the advantages of ZCIs but they have a drawback for general use on this particular saw. Most saws seem to have a handwheel to adjust the bevel angle with a locking lever to fix it, but the GTS 10 J doesn't. To adjust the angle you just loosen the locking lever and pull the up/down handwheel sideways until you get to the angle you want. But when you loosen the locking lever, the weight of the motor immediately tries to swing the saw to about 30 degrees, which would jam the blade in a ZCI.

Hi again John
Just to support what wa said above about having the entire insert flush with the top. That is the best situation you can have.

If you ever decide to separate a box lid from the body then even the slightest deviation on the insert can be a problem.

I see what you mean about a ZCI ... guess you will find other ways ... as a quick fix I sometimes slip a 6mm MDF sheet halfway through the blade and use that as a platform type ZCI for box top removal and crosscutting ply ..

Let's know how you get on with Bosch ... they are generally pretty good.

Regards

Rob

Didn't realise they over engineered the insert, most of the ones I've seen are fairly thin and easily bent.

Am surprised if its cast alloy that it would have been bent as being cast they are generally made to a fairly high standard and any deviations would generally result in a massive batch being manufactured badly. Which if that was the case I'd assume Bosch would be more than happy to rectify.

Originally Posted by tonzeyd

Am surprised if its cast alloy that it would have been bent as being cast they are generally made to a fairly high standard and any deviations would generally result in a massive batch being manufactured badly.

Agreed. So much so that I sometimes wonder whether this insert is designed to be slightly convex rather than dead flat. But I can't think of any good reason for a convex insert in the middle of a flat table.

Which if that was the case I'd assume Bosch would be more than happy to rectify.

After talking to Bosch customer service I emailed them the serial number, part number, description of problem and a photo. That's been received and passed on to "the service team" so I'm waiting for a response from them. Fingers crossed.

Why not just flatten it with a sheet of wet and dry mounted on a glass sheet like flattening the back of a chisel. Its only cast aluminum alloy and wont take much to true up.

Originally Posted by Markw

Why not just flatten it with a sheet of wet and dry mounted on a glass sheet like flattening the back of a chisel. Its only cast aluminum alloy and wont take much to true up.

Problem here is that except where there are reinforcing ribs the metal is only about 2.7mm thick (including powdercoat top and bottom), and I'd have to take off about 1.2mm at mid-length, nearly half the thickness, which I feel would leave it fragile and liable to distort. Also I don't have the manual skill to hold it dead level while sanding so as to take 1.2mm off the middle and nothing off the ends. For me it would be a slow slow job with surface plate and blue.

But as I see it it's up to Bosch to give me a flat one!

John, I would give up on the insert. They usually have a slot fir the saw that is overly wide. Most do, as I did, make one from ply or MDF so that it has zero clearance. This improves performance. Look yp "zero clearance" inserts.

Regards from Perth

Derek

I agree with Derek. Most of the inserts are slotted to suit a tilting arbour, this leaves a wide gap when the blade is vertical. The closer the fit to blade thickness the neater the cut. Use the existing insert as a template for table fit and raise the blade up through the new insert to get a spot on fit.
I prefer to use ply or solid timber as MDF tends to swell with moisture over time.

I don't intend to give up on the maker's insert. The configuration of this saw, in particular the lack of handwheel adjustment for the bevel angle, appear to make ZCIs problematic for bevel cutting.

That said, I'm going to make one or more ZCIs to use for fine work. Today I bought some offcuts of 3mm polycarbonate sheet which will form the top surface and fill the cutout in the table (the shelf on which the insert rests is only 3mm below the top of the table). I'll stiffen it with hardwood epoxied on the underside. Because the slit for saw blade and riving knife has to come within about 10mm of the end of the hardwood at one end and about 13mm at the other, I'll cross-drill the hardwood for 6mm threaded rods to hold it together.