I just bought a D3 Leigh Dovetail jig off of ebay. I haven't received it yet. I was wondering what the difference is between the D3 and D4. The only difference I can see from pictures is that the fingers on the D4 look like they are completely machined. The D3 look like they were cast.
I think the difference is that the D4 has 4 cam knobs, the graphic on the template guide, and the manual (Iíve heard) is better. I thought the fingers were the same, FWIW the fingers on the D4 look like they are die cast. I believe Leigh has a kit to turn the D3 into a D4 if you want to look into that.
I bought the D3 and it is now the same as the D4. There were two changes that made the D4 One was the cam locking handles, and the other is the longer edge guides. The D4 guides are about 6 inches long and make it much easier to set the boards on the jig. The D3's were only a couple of inches long. The new guides are available from Leigh.
Other than that and maybe the manual and video they are the same.
I received the D3 just in time for Christmas. I am really happy with it. I have been looking at the manual and can't wait to use it.
I really love making purchases through ebay. It is a gamble, but once you become comfortable and experienced it is well worth it. I have been looking at Leigh jigs on ebay for about a year. I knew that one day I would use one, but $339 plus is just so expensive. So periodically I would go onto ebay and search on "Leigh Dovetail Jig" and look for bargains. For a year I have always been outbid. I am surprised that some people would actually pay up to 90% of the price of a new jig.
Anyway, a week and a half ago I did one of my searches and came across a D3 with the MMT and a half dozen bits (Whiteside and Leigh). The pictures looked like it was never used and had the D4 upgrades (except for the video). Well, that is what I believe I got. A D3 upgraded to a D4 with the MMT and a brand new set of bits. No scratchs or saw dust on it. When I found it on ebay it had 6 days 12 hours left with a buy it now for $399. I jumped on it. Ebay is a great place to shop. Sometimes it just requires some patience. I probably saved around 1/3 off of what I would have payed from lee valley and whiteside.
I, too, think it's a risk. You could dado the shelves in, but only glue them on the back (or front, or maybe middle) 1/4 or so of the joint. That would leave the balance of the wood free to move. If...