Morticer problems

[Modernist]

I am a fairly experienced , self taught, furniture maker and competent machinist so am baffled as to why I cannot get a result on a recently purchased square chisel morticer, I bought Axminster chisels which appear very sharp out of the box. The problem I get is that the chippings bind in the lower part of the chisel and seize the bit. The whole bit becomes hot with scorched dust appearing. On one occasion I even broke the bit. I have tried slow and fast feed but clearly the clearance between bit and chisel is critical. I am currently working Columbian Pine.

Help!!

 

[woodbloke]

Iirc there should be a fairly large gap at the bottom of the chisel and bit to prevent binding and to make sure that chips get ejected, not sure tho' as it's a while since I used a morticer...bound to be someone along in a mo' who can give a more definite answer - Rob

 

[Paul.J]

I had the same problem last week.Started spraying a small amount of PTFE lubricant on the cutter for each mortise i cut out.Worked fine
Paul.J.

 

[WellsWood]

Hi Modernist,
I used to have the same problems before I learned to set chisel/ bit clearance properly. Have a look here for the method for setting the clearance (amongst other tips). They say a £1 coin, but I find 2p is usually enough.

Hope this helps.

Mark

 

[ProShop]

Which type of chisel are you using, the English pattern or the Japanese pattern chisels :?: And which size chisel are you having problems with ?.

They all need setting up differently.

 

[DomValente]

Follow the procedure as pointed out by Mark, my preference would be Japanese pattern chisels.


Dom

 

[seaco]

Hi Modernist,
I used to have the same problems before I learned to set chisel/ bit clearance properly. Have a look here for the method for setting the clearance (amongst other tips). They say a £1 coin, but I find 2p is usually enough.

Hope this helps.

Mark

I agree with Mark a 2p works fine, I glued a rare earth magnet to the body of the morticer which holds the allen key and also the 2p so it's always at hand... :wink:

 

[Woody Alan]

I do not differ to the advice above. I can only speak from my experience which was exctly the same as yours (after setting as above etc) . The way I acheived success after the burning binding scenario was to take a very small bite at my first plunge...only a mil or two and then immediately move across the mortice by half of the first attempt and then take a bigger bite which worked fairly well i.e. double depth of first attempt. Repeat this process taking half bites of previous attempts and before you know it you are at the other end of your mortice and at full depth. From this point work your way back across the mortice to where you started but this time you will be able to plunge full depth every time. A little time consuming? maybe but I don't do it for a living and cannot afford a quality clico set up. Let us know how you get on. (P.S I believe this method is called staircasing)

Cheers Alan

 

[JFC]

You broke the bit :shock:
You probably know all this but breaking the bit means something is seriously wrong IMHO .
Are you
Cutting the bit down so it gives you 2-3mm clearance from the chisel .
Placing the clearout slot in the direction you have already morticed .
Clamping the work down properly .
Morticing just over half way and spinning the timber over to finish off the mortice.
Sorry if it sounds obvious i'm just trying to help

 

[Modernist]

Thanks guys I now have a functioning morticer. Basically I was not leaving enough clearance above the bit and still dont understand why this should cause the problem - but it did! After all if the chips aren't in the clearance they are in the flute ( I now realise I have Japanese chisels). Also as noted above the first plunge needs to be a bit tentative and then things seem to get easier.

Anyway all fine now so thanks again

 

[DomValente]

Ahh, don't you just love a happy ending?

 

[RogerS]

Hi Modernist,
I used to have the same problems before I learned to set chisel/ bit clearance properly. Have a look here for the method for setting the clearance (amongst other tips). They say a £1 coin, but I find 2p is usually enough.

Hope this helps.

Mark

The link referred to here no longer works. Does anyone have another link?

 

[NewtoWood]

I have tried the link as well but is doesn't seem to work.

Could someone please explain the correct setup as I am having the same trouble trying to get good mortices.

 

[Woody Alan]

To set up the chisel and bit, but the bit in the chisel until it is in as far as will go . Then insert the chisel into the morticer but between the morticer body and the shoulder of the chisel insert the edge of a 2P coin (it's only a spacer) then tighten the bit in the chuck. Once tight take out the spacer/coin and fully insert the chisel so the shoulder is up against the casting.
Also if you are new to it see my advice further up the post, it worked for me.
New to wood I live in Norwich and if you really are struggling then PM me and I'll see if I can can help personally.

Alan

 

[NewtoWood]

Thanks for the information I'll give it a go.

 

[OPJ]

There's also some good information here, on the Record Power site.

Some people like to use a £1 coin with Japanese chisels, although I've never had any problems using a 2p. You may find the greater clearance is beneficial when working with softwoods, for example. Some also say that Japanese chisels are better-suited to working softwood due to the single cutting spur on the end of the auger... Haven't had any problems using them with hardwoods either.

 

[RogerS]

Just finished cutting some mortices on my new 'secondhand' toy and it's brilliant compared to the 'orrible machine I bought first.

The trick is in not trying to cut more than about 1/8" for the first pull in the first position. At least that worked for me.