Water everywhere and the rattling
My Hi-Tech Diamond flat lap has been a second-class citizen in my shop, sitting alone and forgotten in a corner, for a while now. I bought it used to have something to finish the backs of my cabs on but found it hard to use compared to my Genie. Specifically, I hated the water system that I had to keep refilling and repositioning and had trouble with centering my flat laps – leading to excessive rattling, things falling off, and so on. I managed to solve both these issues and this post is about the “how” in case somebody is dealing with them too.
The improved water system
This is how it works:
- You have a pressure tank – exactly like a garden sprayer – that you fill with water and pressurize, which is done by giving the handle a few pumps.
- The pressure in the tank drives the water up through the hose and onto the wheel. There is a valve at the end of the hose (the same one that is on your cup) that allows you to turn the water on and off. The last part of the hose is also enclosed in something called a Loc-Line. It’s a rigid hose build from small segments that can be turned and bent which makes it easy to position the hose exactly as you need.
- The used water flows out into a bucket.
The pressure tank I picked has a 2-gallon capacity. This should be enough to last for a few hours of working time with occasional re-pressurizing (pumping).
The parts
I got this neat hose setup from Hi-Tech for about $24. And I got a 2-gallon sprayer from Home Depot and a 1/4″ to 5/32″ hose barb reducer from Amazon.
Hi-Tech Diamond Pro-Flow 
Home Depot 2 gal sprayer 
1/4″ to 5/32″ barb reducer
Note that you can get a 1-gallon sprayer – or a water pump as an alternative – directly from Hi-Tech too for another $25. The 2-gallon sprayer plus the barb reducer I bought cost about $17 – so not really much of a difference. I just enjoy building things and I wanted a bigger tank. If you’re even crazier than I, you can get the Loc-Line from Amazon or Grainger and build the attachment yourself. I just don’t think you can do it in the same quality for under the $25 – if I am wrong and you can, let me know 🙂
The assembly
The assembly is as simple as these three steps:
Unscrew the handle from the hose. 
Slide the screw cap to expose the hose. 
Use the barb reducer to connect the hoses.
The barb reducer should take some effort to push into the hoses. That ensures proper seal and prevents leaks. It’s always better to get a little bit bigger barb than a smaller one.
I was testing the setup outside first to make sure there are no leaks. As you can see it performed great as a weird flower watering implement too.
Installation
The installation is pretty simple. The only thing I want to show here is how neatly the Pro Flow attaches to the machine.
You just loosen the two screws to slide the bracket over the lip and then tighten them back up slightly so that it’s securely attached. This bracket is the main reason I didn’t want to rebuild this part of the setup myself.
Aaaand that’s it!
The other issue – centering the flat laps.
Apart from the water system, my other grief with the All-U-Need was how to center my diamond grit toppers so that the machine doesn’t vibrate. I didn’t want to buy a backing wheel for each disc so I could glue them on. This was a major issue to me that luckily had a very simple and cheap solution. Hi-Tech Diamond sells this amazing little disc bushing for $5 that allows you to center your flat laps on the backing plate perfectly without needing to glue them on!
You center the little bushing on the arbor. 
Then slide the backing plate on. A part of the bushing is still sticking out. 
That is the part that catches your disc and centers it. 
Then you just tighten it up as usual and you have a perfectly centered disc – no more rattle.
Just be careful if you’re using backing plates that didn’t come from Hi-Tech. I have one from eBay that is just a little bit thicker and the bushing doesn’t stick out – which makes it useless. The one I have from Hi-Tech that works well with the bushing is about 9mm thick while the one from eBay is just a millimeter thicker.
If you’ll be buying the bushing you might want to buy an extra one – the one I have is already showing some wear after just one use so I am not sure how long it will keep working well.
A quick note on alternate watering systems
The solution I picked is definitely not the only one out there. I’ve seen people on facebook post pictures where they replaced the top cup with a 1-gallon water jug, 5-gallon bucket, and so on. You can also do what I did but use a small water pump instead of the sprayer tank and put that into a bucket with water. You can buy one directly from Hi-Tech and Amazon is full of them. Just make sure it can pump the water high enough for what you need (i.e., from ground to the top of the disc, if you plan to have the bucket on the ground).
Happy grinding!
Alice in Jeweler's Land 