Next time you do a rebuild, mix laundry detergent into the dirt. It keeps the dirt wet longer when you water it. The track needs to be watered or else it will break up like you said. OCRC uses clay that has ground red brick in it I believe.
I would agree with the Calcium comment. If you check with the people who run BMX Tracks. They frequently use Soiltac to control the surfaces in the USA. Holland has a lot of BMX too and they may be aware of a brand there. Soiltac is a Liquid Copolymer that bonds the surface. I have raced BMX on these surfaces and they blue groove and grip like asphalt. I have not seen this on a RC track yet but I am suggesting it to may.
We use something similar to that Soiltac. It looks and smells like Elmer's glue and we dilute it 10-1 to 3-1 (water to glue) depending on how thick we need it. After a new layout, the track starts to groove up immediately and once it starts to groove up, there is no maintenance needed. The track definitely does not need as much maintenance than without the glue. If you Can find a supplier for glue treatment (I don't even know the name of it, a friend donated it to us) I would suggest it.
Below is a link to the track website that uses the glue treatment. You can see videos under "Gallery."
I had a few calls about this glue treatment from this post so here is some more information.
This glue works great if you have consistent problems with your track blowing out. We put in a new layout and within 3 days of being open, the track was blown out. We applied the glue and we can go a few weeks without any maintenance, or just sweeping in a few areas. Since our track consists of DG, dirt, clay, and tons of rocks, the glue was great for us. But we have not tried it on other types of dirt yet. If you have clay or good dirt, there is no need for this.
The contractor buys it locally, and you need to have a contractors license to purchase it. They sell it in 250 gallon tote's, which is about 3,000 pounds of the glue. We use 50 gallons of glue (900 gallons glue/water mixture) for each build. Costs end up being ~$125 each time we glue it.
how are you building your clay track without water? I assume you do not use water when you build as clay dries out and will crack when the water evaporates out of it...?
ocrc is by far the best clay. It is watered heavy before the night and misted about every 2-3 hours. I dont know how you maintain your 100% clay track without water.
Thats why we build the track during the winter. So it can rain and snow on it, then when its still damp we flatten the surface. During the summer we mix the dust we sweep off the track with water to fill the holes or make small repairs.
The 1st section was done as it was explained by the guy who sold it to us. Mix with water ( about 1 to 8 ) and put out a few coats. The grip on this section is very high, but because it was to thick to be taken in by the clay there is still a thin coat of Soiltac on the surface. So far this section hasn't been damaged at all. Downside is, that because of the thin layer on the clay, the ground will not take any water. So if it rains there are immediate puddles, and the grip is gone. Because of the thin coat on top of the clay there is also the discussion on "is it still a natural off-road surface ?"
2nd section is on the main straight, its just got one layer mix 1/20. This section doesn't have the thin coat on top of the clay surface, but the Soiltac is now part of the clay. The grip is good and there is no more dust. We threw a couple of buckets of water on it to see what would happen. the clay did take in the water now, and the grip was still "race able". But well have to see and wait what happens if it rains for real.
In the end, we'll probably end up with 2 coats of 1/20.
( see: Soiltac - MAC Vlijmen (5) - reparatie.JPG )
Eitherway its works very good for making small track repaires
We just added a clay base top soil dirt to our track it packs well and keeps it's shape but kind of slick I'm just wondering should we sweep and run it or do I need to water it often it seems that if we sweep the dust off and let it dry a little bit it will groove up we will race on it for the first time tomorrow I hope it grooves up.