Maximum spindle speed

[RogerS]

I've bought a set of these traditional window frame cutters and limiters from Axminster.

Their catalogue makes no reference nor can their tech support offer any recommendations as to the maximum spindle speed or is it limited by the cutter block?

On a separate topic, how do limiters actually work?

 

[Anonymous]

Depends on the block etc but I'd guess 4k rpm or thereabouts
Don't want to disappoint you but those cutters aren't traditional - so if you are actually trying to match something old they will be no good.
True they may vaguely resemble a trad profile from 100 yards away!
Strangely no SM or router manufacturer can supply a traditional window design cutter - it's as though they can't be bothered to look. That's why I started making my own.

cheers
Jacob
PS limiters work by preventing too deep a cut - and the damage that could occur if it is yourself being cut :shock: or if too much force applied straining the cutter, or kickback etc

 

[ProShop]

Roger.

The block with which your going to use the cutters in should have the speed rating stamped on it. Different size blocks different speed. A 100mm * 40/50mm euro block has a speed somewhere around 5500 to 8000 rpm. Some manufacturers blocks may vary

Jacobs right on the limiter question and the traditional cutters you mention, but they make a decent profile. If your manually feeding I hope you bought the limiters or can make your own.

The limiters sit on the block before the cutters and literally prevents you from feeding to fast so the cutter is taking smaller bites at the workpiece, usually they are 1mm or so smaller than the cutter. If you feed to fast manually you can feel the limiter kicking in and trying to gently knock back the workpiece.
Like a chattering effect.

 

[Scrit]

As FelderMan says the speed a block can rotate at is dependent upon its' diameter and balancing. Most Euro blocks in use on smaller machines have a diameter of 75 to 100mm and these can be used safely up to around 7,500 or 8,000rpm. I have a 100mm rebate block which utilises TCT replaceable tips and has 4 inserts, and that block is rated at 10,000 rpm - it is normal with thin TC-RT tooling for the cutterblocks to be rated at higher speeds. As FM says your blocks should be stamped with a max. rpm if they are post-1999 manufacture and all blocks madew since 2000 have been of either chip limitation design or limiter/cutter set design. See here for an explanation. I use some bigger 125mm diameter Whitehill limiter steel blocks and they are balanced for use up to 8,000 rpm as well. It is only the larger panel raisers and tenoning discs which need to be run down at 4,500 rpm.

If you are running a block too slowly it will feel like the cutters are blunt because you are actually pushing against the limiters - the rate of feed is too high for the chip clearance and the limiters are doing their job in limniting the "bite" of the block.

Scrit

 

[RogerS]

Jacob..I agree with your comments re 'traditional'. Fortunately the windows are from a more modern period and so a reasonable match.

I did struggle, recently, to find the right cutters when making some replacement openers for windows that had a lambs tongue profile and so how do you make your bespoke cutters? Angle grinder? But that seems a bit large to create small radiuses etc. Do you use the blanks from Axminster?

FM and Scrit - so it's the block that determines the max. speed in which case I'm OK as the speed range is stamped on the block. Still looks pretty scary with the cutters sticking out as far as they do. I did buy the limiter set :lol: even though I do have a power feed.

However, this is going to be the first time I've used the moulder in anger and so, as I'm disappearing off on holiday for the next four weeks, I'm not going to even think about turning it on until I return. JFC might use a long stick to turn on his moulder...I'm at the very long bargepole stage :wink:

Many thanks for the limiter explanation.

 

[Anonymous]

Jacob..I agree with your comments re 'traditional'. Fortunately the windows are from a more modern period and so a reasonable match.

I did struggle, recently, to find the right cutters when making some replacement openers for windows that had a lambs tongue profile and so how do you make your bespoke cutters? Angle grinder? But that seems a bit large to create small radiuses etc. Do you use the blanks from Axminster?
snip

HSS Blanks from local saw doctor. Rough out with angle grinder, shape up with wheels on 6" bench grinder, nothing special. Make matching pair but don't expect to get them both cutting as they are hand made - so you set one slightly back so it works as balance only.
Been doing it for years - very cheap, perfect copies of any moulding etc.

cheers
Jacob

 

[Scrit]

.....and so how do you make your bespoke cutters? Angle grinder? But that seems a bit large to create small radiuses etc. Do you use the blanks from Axminster?

For limiter blocks the cutter sets are normally ground on a specialist profile grinding machine - £5k and upwards I'm afraid. It is difficult to grind matching cutters and limiters for a Euro block any other way as the cutters are pinned unlike the old pre-Euro Whitehill blocks where the cutters were held in place by pressure alone, so you'll need to accept that with only a single cutter working they'll feed slower.

Still looks pretty scary with the cutters sticking out as far as they do. I did buy the limiter set :lol: even though I do have a power feed.

Actually, nonsensical though it may seem, the regs. state that a power feed on a spindle moulder is still classed as a manual feed so you are still supposed to use limiters (OK, I know that's a trade shop thing, but I just thought I'd clarify). The way to make it a lot less scary looking (and safer) is to add false plywood fence plates to your spindle moulder, thus:

These allow you to tack on a false front fence then plunge through to provide a sort of zero clearance insert which helps support the work:

Please note: Shaw guard removed for clarity :wink:

Probably the most troublesome aspect of making a false fence like that is the bit where you loosen off the fence bolts, grab the ends of the fence and plunge through.

Scrit