minimum wood-thickness for benchtop mortiser?

[Gil Liu]

Hi All,

I have benefitted greatly from browsing the interchanges on this forum -- thanks all for the thoughtful input.

I made my first cuts with a new Delta benchtop mortiser today -- 16-451. I was surprised to not be able to produce holes in a 3/4" piece of plywood. The mortiser worked great for 1-1/2 inch hardwood. Is there a lower limit for thickness of the wood on the table? I couldn't find anything in the manual about needing to raise thinner pieces with an additional support. I know about the depth-stop and it wasn't close to engaging.

Also, any recommendations for chisels (and if so, could you give me an idea of the cost)?

-Gil

[everett lowell]

Welcome to the Creek Gil. hmmmm...I have one to , but never tried to go that thin, I'm gonna go ckeck that out right now!:)

[everett lowell]

oops... I got the 14-651,and the chisel travels all the way through the base.? sorry I could'nt be more help, but I'll keep looking into it-if I come up with any ideas I'll post them.:)l Gil, you sure you got the model # right??

[Rob Bodenschatz]

Can't help you with your issue but I can recommend the Lee Valley chisels:

http://www.leevalley.com/wood/page.aspx?c=2&cat=1,180,42240,53317&p=53252

I got the set of 4 for my PM 701. $105.

[Jim Becker]

Sharp chisels. AND...you can always put another piece of material under your workpiece to block it up higher. There likely is a lower limit and it makes sense to have one...you wouldn't want the bit and chisel accidentally hitting the metal base of the tool!

Oh, be sure you have your bit/chisel adjusted properly. The bit does the work and should be installed so that it's slightly below the end of the chisel. I put mine in about 1/8" or so below. The chisel just cleans up the sides.

[David Duke]

I've got the Jet instead of Delta but I think that the are pretty much the same. On the Jet the arm that raises and lowers the bit is adjustable for different thicknesses (there is only a limited amout of travel per stroke), to adjust for this on the Jet simply pull the arm straight out at the base to disengage it and then rotate to another locking position.

[Mike Cutler]

Gil.

I have the same mortiser. It doesn't have a minimum wood thickness spec. I does have a max travel spec on the head though. If you have the riser kit on it, like I have, the final distance to the table is even greater.
Bottom line, Yes you may have to place material under the workpiece to bring it up closer to the chisel. I use MDF. It's cheap and perfecty flat.
The chisels that came with the mortiser aren't too bad. They just need a lot of sharpening,and honing prior to use.

[Gil Liu]

Thanks all for the prompt replies!

Everett -- good to know you can get yours to drop the entire distance to the table. Hmm, I'm sure about the model # -- I'll go and fiddle more with it later this afternoon (after a Woodcraft run :) )

One more question -- thanks in advance for indulging me. Anyone recommend a particular sliding vise / X-Y table for use with a benchtop mortiser? I think it would be great to be able to move for the next hole without unclamping each pass, but I'm worried that the ones I've seen are so wide and tall that they would bump into the vertical support or raise the workpiece too high.

Gil