Prazi Beam Saw

Any thoughts on the Prazi? I'm trying to determine the best method of making scarfs on 8x10 and 8x12's. My current method is ripping 2 sides with a 7.5" circular saw then using a Ryoba hand saw. Needless to say, this is not a very efficient method.

Thanks in advance.
Dan

I bought one several years ago, and I have no idea where it is. I guess that speaks to how useful I found it for Timber Framing. It's hard to adjust and keep square. It jumps as it cuts, so it's difficult to hold your line. And of course, it's a chain saw, so the surface it cuts is pretty rough. I'd say the best you could hope for is to leave an 1/8 of an inch past the line to clean up with a slick. Way too much work. CB.

If you plan on working with stress skin panels a Prazi should prove useful. I bought one to cut scarfs and SIPs but have only used it for end of tennon cuts on big posts.

I've more recently purchased a Logosol Timberjig to deal with oversized logs. I find I can rip timbers to the line on the visible side and tweak the bar so I'm predictably ~1/16th above it on the far side. The cut is very smooth for a device designed to produce rough sawn lumber and timbers, cleanup with a hand plane is very quick.

If you have a good strong chainsaw then the price is going to be about the same as a Prazi.

Dan,

I will ditto the comments about Prazi lacking precision. The base is very small and easily wobbles. They are handy for rough shaping, and I use one to cut sweeps and radiuses, then finish with hand tools. I am fabricating a larger base to improve accuracy. A sharp (!) chain is very important.

Another thing is that the frass piles up on top of the wood, obscuring the marks and lines. I added a compressed-air jet to mine that blows the dust away.

For scarfs, I think a Prazi would be no advantage. I cut mine very much the way you do, and achieve almost invisible joints. I use a 5 point ripsaw with a lot of set; finish with chisels.

The specific design and dimensions of any joint can be selected to suit the capacity of the particular tools on hand, with an eye to making them efficient to cut. There are dozens of possible styles of scarf.

Except for a very few circumstances, a chainsaw (gas or electric) can do anything the prazi will, with careful technique.

Good luck.

Pete

There has been some discusion of this topic on the UK Carpeneters Fellowship web forum. Look at "worm drive saws / Prazi beam saw". There is also some talk about the Mafel carpenters chainsaw which does a similar job, slightly better for much more money.

You might also want to look at the discusion there about "13" saws" too, as my advice for cutting larger timbers is to use the method you are and perhaps consider a larger circular saw (10 1/2" or 13" or even 16".