Thread: Mitre Jack Puzzle

Nice score Martin.
It looks like the screwed on pieces are sacrificial parts that bring the planing surfaces up to the right level to work . Screwing them on is no good unless the heads are sunken or nailed and the same . A better way would be to glue on the sacrificial pieces with paper in between the glue joint so they just peel back off when new ones are needed. Glue them on a touch thick and plane them true.

These mitre jacks were used on the 45 degree angle side in a working position where long pieces could be coming through the jaws and be supported behind that on the bench. And the 90 degree working side doing the same, facing up . The base pieces on your one need to be taken off and fittings made that will hold it to your surfaces both ways. A long T piece made up of two boards that bridge both ends together that can be held in your vice or lay down and screwed to a bench top or work table top is a possible solution.

My Mitre Jack has the T board and can be screwed down to a top for this position of work.
IMG_2291.JPG



The other side for the 45 degree work has two ends of the T board braced with corner blocks
and a space left for a vice to hold it . The top of a leg vice or a steel face vice? So it wont fit my longer face vice and I haven't had the need to change it yet for that . I could also screw it to the edge of the work table using the two holes the previous owner put in it that are holding it on in those pictures.
IMG_2299.JPG


Rob

Thanks Rob,

My guess, like yours is that the screwed sacrificial timber was a "later" addition-but it is not new change, the screws are old.
Like the suggestion of using paper between the sacrificial pads and the rest.

What sort of glue do you suggest?

Concur on taking off the existing mounts. Have not figured out how the mounts worked. Assume there a logical reason for what's thereabout but cannot decipher the purpose.


Have in mind is something like your arrangement but with wings. The intention is to fit to the bench a bit like a Moxon Vise for both positions. Reason- Don't have an "effective' tail vise my bench. Bit space deprived, many compromises. Think what's designed will work but time will tell.

Cheers

Originally Posted by MartinCH

Thanks Rob,

My guess, like yours is that the screwed sacrificial timber was a "later" addition-but it is not new change, the screws are old

.
My one looks all original . No later additions that I know of. The T board with the screwed corner blocks look to be the way it was made.

Originally Posted by MartinCH

Like the suggestion of using paper between the sacrificial pads and the rest.

What sort of glue do you suggest?

.
That was usually done with hide glue as when you lever off or the added piece gets a knock and starts coming off the paper splits in half. Hide glue washes off the easiest with hot water. PVA or Titebond also work well. As long as its a water based glue so you clean up back to the original surface without having to scrape or sand.

Originally Posted by MartinCH

Concur on taking off the existing mounts. Have not figured out how the mounts worked. Assume there a logical reason for what's thereabout but cannot decipher the purpose.

.

Looks to me like they could have been put on to hang the MJ on a wall. Maybe on a couple of nails? Hold it up and see if that's the best way you would have done that just to look at. These things end up in someones shed and they either have no idea what it was for, or they know and never use it, and its to nice to throw but needs to be stored out of the way.

These days my machines cut joints and there is hardly ever a need to use the MJ. 30 years back with more limited machinery and I did a few jobs where I had to re make missing cornice mouldngs for Victorian bookcases I definitely had a need for it then but got by without using it. It was stored away in a box of tools belonging to my Father and I never knew what it was for.

I do have two bookcases both needing a new cornice mouldings to do but the Makita drop saw will still probably do them more straight forward and faster . I will probably give it a try out though. What I'm more interested in with the MJ is trying it on an actual traditional one of 18 th Century style chair or sofa job that I sometimes do. The tenons on those are where I think it would be fantastic.

Originally Posted by auscab

.

Looks to me like they could have been put on to hang the MJ on a wall. Maybe on a couple of nails? Hold it up and see if that's the best way you would have done that just to look at. These things end up in someones shed and they either have no idea what it was for, or they know and never use it, and its to nice to throw but needs to be stored out of the way.

These days my machines cut joints and there is hardly ever a need to use the MJ. 30 years back with more limited machinery and I did a few jobs where I had to re make missing cornice mouldngs for Victorian bookcases I definitely had a need for it then but got by without using it. It was stored away in a box of tools belonging to my Father and I never knew what it was for.

I do have two bookcases both needing a new cornice mouldings to do but the Makita drop saw will still probably do them more straight forward and faster . I will probably give it a try out though. What I'm more interested in with the MJ is trying it on an actual traditional one of 18 th Century style chair or sofa job that I sometimes do. The tenons on those are where I think it would be fantastic.

Hi Rob

Will use hide glue and paper to install new lining. Not sure if nails were used in the holes. The holes are skewed and the no sign of damage from nail extraction. or recess for countersunk. They have me flummoxed. There's to much effort in those supports to suggest they don't have purpose, but what that was I cannot tell. Suspect there is a part missing.


As for miter jack uses, we the issue one is the home shop doesn't really have space for at drop saw, particularly with indeed outfield space. Digressing slightly , I was using a MFT style track saw for may cuts but these days is use a bench hooks and the no set 77 style saw, unless the part really large. Basically cause I can set the bench hooks anywhere , the guide stays accurate (no set on the saw) and dust that sometimes built at the fence corner and threw accuracy off, when I didn't pay attention, isn't a problem. The upshot is that the bench hooks are faster (for dry saw deprived me ) unless the cuts are large/long.

I adopted my vise to run as a MJ. From that experience this what I have noted
-chip out controlled, easy to skew a plane or run across,
-able to trim "smidgeons"
-and one thing I didn't expect my planing stokes are significantly more powerful than what I could achieve on a shooting board, can take quite thick end grain shaving though WA hardwoods. The limit of this is not my ability push the plane though timber but when the plane starts chattering- either I not compelling the plane or something in the plane started to deflect.
Also, iyt alway good to avoid dust/ noise generating activity, dust alway s seems to travel further and get into more places than I like to think about

The bad point of the current is there too much wracking in my vise and I didn't build the end bench with this use in mind. Slowly aquaring the parts to build a custom vise to improve the abit of that location.





Back to the MJ, when I get it back to serviceable curious if I can maintain the same strong stokes, and if parts can be ganged between the jaws easily. Slicing 4 mitres once with no chance slipping could be effective.


Cheers

One more thing - as you mention Rob , really like the precision that on can work to with MJ's. having that large 3 sided defence surface is fabulous.