Best tool for undercutting door frame?

[John E]

I have some hardwood flooring to lay, and this will involve undercutting 8 door frames. I'm looking for the best tool for the job.

Some web sites recommend using a 'hard back mitre hand saw' which I have, but I would prefer a power saw, since there is rather a lot of cutting to do, and on the previous occasion that I used a hand saw, the task took a long time, and caused significant subsequent back pain. ;-)

There seem to be a number of items available on the internet, but most of the power tools are available in the USA only (as far as I can see) - e.g. 'door jamb power saw' and the Bosch 'fine cut power hand saw'. I did find one item

(the Bepo twist) but this was nearly £400, and would seem to be a bit over the top for my needs. I quite like the look of the Bosch fine cut power hand saw because that would be useful afterwards too. However, I couldn't find it on a UK web site (at 250V).

I did find this one:

?division=hw&ccat_id=9647&prod_id=7574 the Bosch PFZ 600E All-purpose saw. Will this do the trick?

Any and all suggestions gratefully received...

[George]

because that would be useful afterwards too. However, I couldn't find it on

?division=hw&ccat_id=9647&prod_id=7574> the Bosch PFZ 600E All-purpose saw. Will this do the trick?

How thick is the flooring? I laid some flooring just before Xmas and was faced with the same situation but quick thinking I came up with the solution.

As this was HW flooring its thickness just came to the height of the top of blade in my biscuit jointer which couldn't have been more perfect. I just used the biscuit jointer to cut out all the bottom section of the door architraves.

Perfect!

[John E]

Thanks. The flooring is 15mm to which the underlay (about 3-4mm) needs to be added. So your suggestion would seem to fit the bill. (And a lot cheaper than £400!).

[George]

> l_1640VS/display_~latest_prices

> E964514E3903F2F91A?division=hw&ccat_id=9647&prod_id=7574

If the blade is not high enough alls you do is put a shim of some sort underneath the shoe(base)to higher the cut.

The only thing you have to watch is make sure the end of the blade does not cut the skirting if in situ? and set the depth of cut to architrave thickness.

[robert]

Possibly a multiangle bit MAB - supposed to be able to cut slots with them.

[John E]

Yes, I have seen one on the web which will easily do the necessary height from the floor. The skirting will have been removed anyway before laying the floor.

Thanks for your help.

John

[John E]

Thanks. I'm a bit doubtful that this would work because of the thickness of the drill body. At least, I'm doubtful that I would be competent enough to make it work!

[George]

You're welcome.

Keep an eye out for the nail at that level you're working to. :-(

[Maris]

I've got a whole lot of flush fire doors that I intend to trim to size to replace my existing ones. I have purchased an Einhell circular saw for the purpose, which cost me £56.94 from DIYtools.co.uk. The Bosch thing you show is really not the tool for the job. I would certainly take the door off to do it as well.

Maris

[Roger Mills]

because that would be useful afterwards too. However, I couldn't find

?division=hw&ccat_id=9647&prod_id=7574> the Bosch PFZ 600E All-purpose saw. Will this do the trick?

The All-purpose saw is totally unsuitable for this purpose! Firstly, you'd have to lie it on its side, and even then you wouldn't be able to get the blade close enough to the floor. Secondly, the blade will bend and go all over the place and be uncontrollable. [This saw is fine when you span the item to be cut - such as a small tree branch - but lethal if you try to cut with just the tip of the rapidly reciprocating blade].

As others have said, if you *must* have a power tool, a biscuit jointer is probably the way to go.

But I did all mine with a sharp flexible hard-point handsaw when I laid wooden flooring in my hallway (and I had *lots* of doors plus a newel post to do!). This was quite simple, and very controllable, using a flooring offcut (with underlay under it) as a guide - just sliding the saw over it.

I assume that you *are* going to remove the skirting boards - and replace or renew them after the flooring is down?!

[mrcheerful]

?division=hw&ccat_id=9647&prod_id=7574

I would use a fein supercut. my pfz550 would not be suitable at all

Mrcheerful

[John E]

Thanks Maris. It is the frame rather than the door itself which I will need to cut. In theory, I understand it is best to remove the door frame and cut it on a table - but that isn't really an option for me.

Maris wrote:

> because that would be useful afterwards too. However, I couldn't

?division=hw&ccat_id=9647&prod_id=7574>> the Bosch PFZ 600E All-purpose saw. Will this do the trick?

[John E]

> because that would be useful afterwards too. However, I couldn't find

?division=hw&ccat_id=9647&prod_id=7574>> the Bosch PFZ 600E All-purpose saw. Will this do the trick?

O.K. I'm getting the message that the 'all purpose saw' is unsuitable. I will remove the skirting boards. Certainly when I did this before with a hand-saw, it was hard work, but it could be that the saw I used was not as sharp as it might have been.

Thanks.

[Andy Hall]

?division=hw&ccat_id=9647&prod_id=7574

I've done exactly this with oak door frames and used a Fein Multimaster for the job.

This is a multi-purpose tool which is highly controllable and has a large range of accessories for other jobs as well. It's not a £20 tool, nor a £400 one either, but I probably use it more than any of my power tools.

the frame cutting application, a depressed centre saw blade is the most suitable to use - there are either round ones or segment versions. The latter can be used precisely into a corner.

In order to cut away a section of frame, the easiest way is to take a piece of material (e.g. softwood or sheet material) of a thickness equivalent to the height above the existing floor. Locate this up to the frame and it will form a support for the blade and give you a neat and straight cut.

If you look at the Applications area on this site and under Replacing floor coverings, there is an illustration on how this is done.

I have also tried similar operations using a general purpose saw similar to the Bosch PTZ. The problem is that it is difficult to get the blade close enough to the floor and straight.

Another alternative you could try, which will work but is time consuming, is a Japanese pull saw. These have thin and flexible blades and can also be located using the top surface of a piece of material pushed up to the frame.

[John Rumm]

I would say you have a few options:

longish hardpoint hand saw - used against a bit of up turned flooring - you will need to introduce enough latteral force on the blade such that the bit doing the cutting is flat against the spacer. As you say, hard work, but a good finish is achievable.

Used like above, you would also be able to use a reciprocating[1] saw with a long (9-12") wood cutting blade. Again you use the capability of the blade to bend into the right position for the cut. This would be a good solution if there are hidden nails in the base of the jamb (you can get timber / nail cutting blades)

Biscuit jointer - as others have said - you will need a packer under it equal to the thickness of the finished floor level less the kerf of the blade and the offset from the base of the jointer.

My weapon of choice would be a Fein multimaster with a cranked eCut[2] or segment blade - that will give a fine and controlled cut. Again use some upturned flooring as a spacer - no need to adjust for the blade kerf since the blades are so fine.

[1] ?pf_id=19591&name=fein&user_search=1&sfile=1&jump=0

[George]

You have mentioned the Biscuit Jointer also as a suggestion,why would you use this fein tool which is slow and cumbersome as to the BJ which can do it in one cut practically ie position,plunge,finish.

The FM you have to move the tool along the job trying to keep moving the blade along a straight line. I reckon this FM is useful where laminate is being fitted as the BJ does not go low enough for cutting the achitraves.

[Andy Hall]

Have you used a Multimaster? It isn't slow and cumbersome - I trimmed several oak frames in short order.

The Biscuit Joiner may not have enough blade projection.

Very straightforward if you follow the recommended example and rest the blade on a piece of material of the correct height.

It's useful anyway

[George]

Mine projects 3/4" at the cutting tip without the adjustment stop taken off.

I would imagine an inch would project with stop taken off which would be more than adequate even for victorian mouldings.

[Roger Mills]

The OP needs one of these like a hole in the head!

[John E]

Hello John. Thanks for this. I've been reading some customer reviews on the Fein multimaster, and one comment which comes up is that the accessories (e.g. for sanding and the saw blades) are expensive, rather flimsy and wear out quickly. One poster suggests that the 'flimsyness' could be due to applying too much pressure. Do you have a view about this?

I ask, because this looks like the most suitable all-round tool for me - taking account of the need to buy something which will be useful for a lot of other projects too.