Horizontal Mortiser Cutters (Bits)

[Floyd Cantrell]

Hello fellow woodworkers, I have been looking at this forum off and on for some time, my first time posting today. I have question for some of you that have a horizontal mortiser. Where do you get the cutters? I have done some Google searches and came up empty. I recently bought a used Mini-Max with the horizontal mortiser attachment and I did buy two cutters from Mini-Max USA, they are HS Steel and I would like to find someone that makes carbide cutters, also Mini-Max only stocks two sizes. I have attached a picture of the cutter that I tested on, have not used on any hardwood. They did work great in the poplar

http://www.sawmillcreek.org/attachment.php?attachmentid=23230&stc=1

[Ellen Benkin]

I've used these machines with a spiral upcut router bit that should be available almost anywhere you can get good bits in a variety of sizes.

[Jamie Buxton]

Onsrud has a whole line of cutters for horizontal mortisers.

[Dev Emch]

Hi Floyd..

There are actually two types of horizontal mortiser cutters. You have the maka type and the type you posted. For maka cutters, you have to have them either custom made or buy them from Dankert in one of the carolinas. The type you listed in the photo are available from Felder USA if I am not mistaken. Good Luck.

[Mike Wilkins]

Laguna Tools has them in SAE sizes. I got a set of 5 for around $140 bucks.
I could be wrong on the cost
Good luck and watch those fingers.

[Jim Becker]

Onsrud has nice cutters as Jamie mentions. Richard at Microfence.com sells them, I believe....

[Sam Blasco]

Hey Floyd,
Mini Max stocks more than two sizes, but at the time you called there were probably on two sizes in stock. The reason stock is low at this moment is that I have been working on changing suppliers for more variety, and as of yesterday I shook hands with and Onsrud rep, who will now be supplying us with mortise cutters -- Off the shelf 4 flutes, similar to what you've shown, but with 4 flutes instead of two. And they will be making some specialty spirals for horizontal mortisers (both left and right) to the specs I gave them. They will be longer than off the shelf spirals and the shaft will shrink by .002" behind the cutter to prevent any undo friction on deeper mortises, yet allow for more bit strength because you won't have to have a longer cutting edge or spiral.

What you picture is a cutter for an oscillating mortiser (no plunging) that can cut in either direction of rotation. If you tried to plunge more than 1/16" you probablly didn't like the results. With that type of cutter the mortise is made moving side to side only, and will yeild very clean mortises quite quickly. If you want to plunge for doweling, use drill bits or router bits, but make sure and determine whether your mortise attachment is on the back side of the J/P (right hand rotation) or the front side of your J/P (left hand rotation) and get the appropriately oriented cutter. I doubt you will find the "birdsmouth" cutters like the one you have in solid carbide, and if you do, I don't recommend getting any sized 3/8" or less - they will tend to snap. Also keep in mind that with solid carbide, expect to pay premium prices, while sacrificing cut quality a bit (not that this will matter that much for a mortise). High speed steel, in this application, still offers the best bang for the buck.
Hope this helps,
sam

[Steve Rowe]

Hey Floyd,
Mini Max stocks more than two sizes, but at the time you called there were probably on two sizes in stock. The reason stock is low at this moment is that I have been working on changing suppliers for more variety, and as of yesterday I shook hands with and Onsrud rep, who will now be supplying us with mortise cutters -- Off the shelf 4 flutes, similar to what you've shown, but with 4 flutes instead of two. And they will be making some specialty spirals for horizontal mortisers (both left and right) to the specs I gave them. They will be longer than off the shelf spirals and the shaft will shrink by .002" behind the cutter to prevent any undo friction on deeper mortises, yet allow for more bit strength because you won't have to have a longer cutting edge or spiral.

Sam - When do you expect these will be available?
Steve

[Sam Blasco]

Sam - When do you expect these will be available?
Steve

Should have the 4 flutes in a couple of weeks. The others will be a special run, 8-12 weeks before the proto-types will be ready for me to test, and then if it looks like a winner a full run will be made. So, not really sure when those will be available.

[Floyd Cantrell]

Thanks for all the input, I now have a file of suppliers. I downloaded the Onsrud catalog and they seem to have the cutters needed.

Sam

Thanks for the heads-up on the design change from Mini-Max. Sorry for the confusion on what they stock, it was just an impression when I went to order, can't remember the exact words they used.

[Richard McComas]

You can get those from Felder USA. That type of cutter seems to work the best for me.

[Alan Turner]

I use end mills, 2 flute spiral, solid carbide, from Bentz Tooling, near San Jose, CA. Nice folks. I have some which are small, and a big 1/2" by 5" OAL. So will cut in about 4" or so. I don't recommend using one that is longer than needed. My slot mortiser is a Griggio, and runs at 4000 rpm. I think the big boy was about $55 or so, and the smaller ones in 1/4, 5/16 and 3/8 were about $15 or so. Not too expensive, and they last quite well.

[Rick Lizek]

Been using slot mortisers for over 20 years and have tried all the types of cutters available. Two flute HSS endmills are my main choice. Four flutes tend to be slower. Think of rip blades...less teeth cut better in long grain. Carbide is fine but costs more.

[Steve Rowe]

Should have the 4 flutes in a couple of weeks. The others will be a special run, 8-12 weeks before the proto-types will be ready for me to test, and then if it looks like a winner a full run will be made. So, not really sure when those will be available.
Sam - When you get these bits in and tested, could you post the results comparing them with the 2 flute design? I have recently tested some very inexpensive 4 flute endmills with some good results however, the cutting depth for the diameters that I like is too short. To suit me best, the spirals really would need to be about a half inch longer.

[Sam Blasco]

Sam - When you get these bits in and tested, could you post the results comparing them with the 2 flute design? I have recently tested some very inexpensive 4 flute endmills with some good results however, the cutting depth for the diameters that I like is too short. To suit me best, the spirals really would need to be about a half inch longer.

The four flutes are in and I've been using them for a little over a month now. They aren't quite as fast as the two flutes, but the mortises are cleaner and a bit more consistent (though, the difference is very marginal). They haven't got me the spiral they were going to work up for me. Could be a time for a call to see what's going on. What depth are you looking for? and in what diameter?

[John Renzetti]

Hey Floyd,
Mini Max stocks more than two sizes, but at the time you called there were probably on two sizes in stock. The reason stock is low at this moment is that I have been working on changing suppliers for more variety, and as of yesterday I shook hands with and Onsrud rep, who will now be supplying us with mortise cutters -- Off the shelf 4 flutes, similar to what you've shown, but with 4 flutes instead of two. And they will be making some specialty spirals for horizontal mortisers (both left and right) to the specs I gave them. They will be longer than off the shelf spirals and the shaft will shrink by .002" behind the cutter to prevent any undo friction on deeper mortises, yet allow for more bit strength because you won't have to have a longer cutting edge or spiral.

What you picture is a cutter for an oscillating mortiser (no plunging) that can cut in either direction of rotation. If you tried to plunge more than 1/16" you probablly didn't like the results. With that type of cutter the mortise is made moving side to side only, and will yeild very clean mortises quite quickly. If you want to plunge for doweling, use drill bits or router bits, but make sure and determine whether your mortise attachment is on the back side of the J/P (right hand rotation) or the front side of your J/P (left hand rotation) and get the appropriately oriented cutter. I doubt you will find the "birdsmouth" cutters like the one you have in solid carbide, and if you do, I don't recommend getting any sized 3/8" or less - they will tend to snap. Also keep in mind that with solid carbide, expect to pay premium prices, while sacrificing cut quality a bit (not that this will matter that much for a mortise). High speed steel, in this application, still offers the best bang for the buck.
Hope this helps,
sam

Hi Sam, Felder has them in carbide but they are much more expensive. I've not used the carbide as I've found the HSS work great. I've been able to get about 1/8" cut on mine and then just continually move back and forth as moving in about an eighth on each side pass. Works real good. I've got a variable speed on my mortiser and that helps to adjust the speed to the cutter.
take care,
John

[Steve Rowe]

The four flutes are in and I've been using them for a little over a month now. They aren't quite as fast as the two flutes, but the mortises are cleaner and a bit more consistent (though, the difference is very marginal). They haven't got me the spiral they were going to work up for me. Could be a time for a call to see what's going on. What depth are you looking for? and in what diameter?
Sam - I usually use the 1/4" and 5/16" bits.
Thanks,
Steve