Open mouth of 604 for LV iron/cap iron set?

[Phil Stone]

I recently received Lee Valley's Stanley replacement iron and cap iron combo for my Bed Rock 604. I'm a relative newbie with hand planes, so setting this up has raised a few questions.

I moved the frog back as far as it will go without changing the bed angle. I.e., if I move it back any further, the blade will contact the back of the mouth before it is fully seated/coplanar on the frog. I can advance the blade enough to get very thin shavings, but the mouth is practically closed. Small chips easily get stuck. Am I doing something wrong with the frog/blade adjustment, or will I need to open the mouth a bit?

I wrote to Lee Valley customer service, and they quickly replied that although the blade/iron set is meant as a direct replacement for Stanley planes, the mouth width is somewhat hit-or-miss, so I may need to open it up.

Now, this 604 is in decent shape, but it's a user (I found it at a yard sale for fifteen bucks a few years ago!); I'm not a collector. Still, I don't want to screw up what seems to be a valued vintage plane. Should I file the mouth? If so, should it be the back or the front of the mouth?

Thanks for any advice.

[lowell holmes]

I have the LV iron and cap iron in my 604. I took a small mill bastard file and gently enlarged the mouth towards the front of the plane. I only filled a small amount until it fit. It was worth the effort, as the plane has always been good, it's better with this iron and breaker combination.

You might want to get machinist dye or a black felt marker and mark the front of the slot, then scribe the line you want to file to. I can't imagine it would affect the value of the plane if you do it carefully. It's not obvious the plane has been altered. I also did it successfully on my 605 and 607.

[Jim Koepke]

+1 on what Lowell said.

It is surprising how fast the cast iron can be removed with a file.

Remember you can always remove a little more metal. It is impossible to un-remove the metal.

My preference is a safety file. That is one where the sides do not cut. An auger file would work. There are other files with this feature.

jtk

[Phil Stone]

Thank you both for your replies. What angle would you recommend filing the front of the mouth? Parallel to the frog?

[Jim Koepke]

Thank you both for your replies. What angle would you recommend filing the front of the mouth? Parallel to the frog?

The front of the mouth should be filed to form a slight V with the frog angle if viewed from the side. The front of the mouth should not have any way a shaving can get caught or jam before it clears the area.

jtk

[david charlesworth]

I would only go 10 or 15 degrees forward.

(This should not be necessary if the C/B front edge is accurately done, but it will do no harm.) Do not bevel or round the intersection with the sole.

Polishing the front edge of the throat is a nice touch.

Best wishes,
David