Crosscut Sled

After all the effort that went into putting in a floor, it was finally time to benefit from the work. At some stage in September, I bought a table saw. It is a Bosch PTS10 and it came with a relatively lightweight frame to put it on. The green coloured Bosch line are for DIY enthusiasts etc, not really for professional use (the equivalent Bosch GTS10 - the blue line - is almost three times as expensive). While the saw is very solid and has a relatively powerful 1500W motor, you can see where they cut costs. The top of the saw - the flat surface that the timber is actually cut on - can't be adjusted. At least, I can't see how it can be adjusted. I measured to check how parallel the blade is to the fence that came with the saw and it is acceptable. The saw has an attachment for a vacuum cleaner. I need to figure out how I can set up a master/slave combination where the vacuum cleaner comes on automatically when I turn on the saw (and turns off when the saw goes off).

Setting up the fence at exactly 90° to the blade

After looking at videos on Youtube (e.g. the WoodWhisperer), it seems that for accurate joinery, almost all of the time cross cut sleds were used. The beauty of a cross cut sled is that you can assemble a jig that will cut 100% perfect square lines irrespective of the table saw setup. The blade could be well off 90° to the table saw fence, but when you assemble the cross cut sled, you can set it up square. For my saw I needed a coated sheet of plywood about 80cm x 70cm (it hangs over the left side of the saw by about 15cm - this is deliberate). I also needed two runners. These fit into the slots on the table (the slots that the angle fence usually runs in) and keep the sled running in one plane. Finally, on each side of the sled I needed fences. Only one fence (the one nearest to the operator) is critical - it absolutely has to be dead on, as the timber you cut registers against it and it must be at 90° to the blade. I was thinking of going to the building supplier for the materials but it turned out Stuckenberger had everything and he even cut the timber with his table saw (completely different league).

After clamping the fences, I pre-bored the screw holes and countersunk them as well - otherwise the screw heads would catch on the table. It worked out fairly well. To cut the slot that the saw blade actually travels in, you have to first drop the blade below the table, then turn the saw on and raise the blade up slowly. Given the length of the fences (particularly the important one between the operator and the blade), it should theoretically be possible to get very square cuts. Once the second fence was installed, I tested it with a two metre long piece of timber. Usually, you'd have no chance of crosscutting a piece like that. It would be impossible to hold the piece square to the blade - and if it moved (which it very likely would) you could get a savage back kick from the saw. With the crosscut sled, I clamped the timber against the fence and cut it with no problem whatsoever. You might not be able to see from the photo, but the cut is absolutely, perfectly square. That beats having to set up a circular saw with a guide.

Here's the sled set up to cut a long piece of timber across the grain

Partyraum Part 5

Now the floor is starting to look a bit better. The self levelling compound did its job and the surface is now smooth. It isn't completely level across the whole area, but it is acceptable and if I put tiles in at some stage, it should be easy to do. There are a couple of places where I think the compound might not last all that long (probably the areas where I filled with cement powder) but it should be easy enough to sand off and redo - if I have to. Once the compound was poured, it was spread with the same kind of trowel you use for laying tiles (the one with the teeth). You can walk on it after two hours - though mine was thick in places and I left it a couple of days before walking on it.

Once it was dry, I had to decide on how to treat it so that oil and grease and other kinds of dirt wouldn't stain it permanently. Still thinking that I might eventually tile it, I decided that a floor paint is probably the best way of doing it. If I do decide to tile it, I can just sand it, treat it with Tiefengrund (Polybond) and then the tile adhesive will hold. If I were to use some other kind of finish, like the acryl stuff, I'd have to do considerably more sanding if I were to tile it later. Anyway, Sven told me there was a shop in Landshut that was closing and he managed to procure two buckets of heating room paint for €1 a litre. Heating room paint is impenetrable for heating oil and is a requirement if you have a room with oil tanks. It just means, if the oil leaks, it won't get into the ground water. You actually have to paint three times for a heating room. As we'll have pellets, it doesn't matter. I used it because it was cheap. The colour was described as 'brick red' but I think it is more terracotta than anything else. I painted it twice and now it looks like the picture. It is a durable, non-slip finish. Dust etc still 'sticks' to it though - i.e. if there is fine, damp dust, like on the underside of a show, it will mark and you won't be able to get rid of it fully with a normal brush - you'd have to wash the floor. If I had applied the acryl finish, dust would have no chance and a brush would clean everything. However, tiling would be an issue.

Now that I have a floor, I set up my table saw. Next project is to make a workbench with a clamp on it. It is way too cumbersome to do anything without one. In the picture above you can see the timber I'm going to use to finish the edge of the gallery - i.e. the top of the wall. The carpenters had to take off the 'cornice' I had on it (only a skirting board upside down) to get the stairs in. I got the timber from Stuckenberger. I'll probably have to use the router to get a bit of a nice bead on the underside of it - but that's also a job I'd rather do when I have a workbench.

Partyraum Part 4

Almost a month ago we put in the concrete. It was ordered a week previously with express instructions to (a) use a chemical delay agent to stop the concrete setting too fast and (b) to ensure that the driver of the lorry had a 6m long slide for the concrete. The reason for (a) was that because of availability of help, we could only start at (planned) 14:00 and 33% of the help (Sven) had to leave for night shift at around 20:00. The reason for (b) was that it was intended that the concrete be poured pretty much in the middle of the room, so we'd be able to spread it easily.

As you might anticipate neither (a) nor (b) worked out. First, the lorry was an hour and half late - meaning we started pouring at around 16:00. Second, the slide was only 4m instead of 6m meaning we had to quickly construct a makeshift extension (which worked but made a bit of a mess in front of the door). Third, it became obvious pretty soon that the chemical agent (if there even was chemical agent in it) wasn't working and the concrete was setting too fast.

Under the circumstances we managed to get it some way even. Due to having to work full out until midnight, I didn't notice until much later that I had a nasty cement burn on my right leg (ended up with six trips to the doctor over the following four weeks and it still isn't right yet and will probably leave a nasty scar). I also didn't really have time to float the floor before the concrete set. The next day I floated as much as possible, wetting the floor as much as possible and using cement to fill in the worst of the holes. It worked out ok-ish. The main thing was that I wasn't too far off on the levels. Checking with the laser it looks as though the maximum deviation from the level I need is about 2cm. Those deviations are quite local though (meaning there are small steps rather than long hills). What was immediately obvious was that a surface will have to go in. There is a self levelling compound that can be poured like soup on to the floor. As a viscous liquid it levels itself like water and the finish is perfect. It is relatively expensive though, at €20 a 25kg bag. I'll need 10-15 bags, but it will be worth it for the finish.

Before the self levelling compound goes in, two things have to happen. (1) we have to run a concrete sander over the floor to remove small steps/ridges and to take the worst of the problems away and (2) the raw surface has to be treated with an epoxy compound so that the new surface sticks (kind of like polybond). The other Sven is going to give me a hand and he knows what he is doing, so come Saturday evening there should be an acceptable finish on the floor that I just have to paint with floor paint.