Making custom spindle moulder cutters

[Trevanion]

I nearly joined this conversation earlier. Glad I didn't. You raise the point which I was going to: mild steel. Are spindle moulder cutters made from mild steel, or something harder?

Pretty much all steel cutters you will find except the reaaaaaallly early ones will be High Speed Steel (HSS), Usually grade M42 (Which is seriously hard wearing due to Cobalt content). There's a lot of debate whether you lose the temper with the tooling when heavily grinding on HSS but I've not noticed much difference if it gets a little blue.

Everything else is usually either Tungsten Carbide or Stellite.

 

[johnnyb]

It's beyond my experience but I'm sure I've seen set ups that grind using a stylus and an angle grinder copy lathe style. I guess you have to remove the bulk just leaving the last smidge. Then do the final profile on both knives.

 

[Jacob]

I nearly joined this conversation earlier. Glad I didn't. You raise the point which I was going to: mild steel. Are spindle moulder cutters made from mild steel, or something harder?

Pretty much all steel cutters you will find except the reaaaaaallly early ones will be High Speed Steel (HSS), Usually grade M42 (Which is seriously hard wearing due to Cobalt content). There's a lot of debate whether you lose the temper with the tooling when heavily grinding on HSS but I've not noticed much difference if it gets a little blue.

Everything else is usually either Tungsten Carbide or Stellite.

Yes HSS as far as I know - I just buy "spindle moulder blanks". They seem to keep an edge for a very long time even if blued by my crude metal working!
Another point about samples is that you can carefully strip paint and find out what the details really are like. A lot is easily overlooked otherwise. Often they are made up e.g. Roger's first architrave could be in three pieces - a back piece plus two moulded strips planted on.

 

[Jacob]

..... Still possible DIY and cheap.
....

Perhaps we could have some photos of your custom cutters ? I'd be very interested to see the level of detailing and finesse that you can achieve.

I'll get around to photos of the cutters but they look untidy compared to the machine made ones.
However they do produce very accurate copies. I'll see if I can find some old/new samples of actual mouldings. I had a huge sample box but it may have ended up as firewood.

 

[Doug B]

. I had a huge sample box but it may have ended up as firewood.

Well if you will redesign the workshop & have a big clear out then these things will happen :shock:

 

[Sgian Dubh]

You are, as usual, talking complete and utter boll ox.

Hi Roger, I agree that Jacob can be quite dogmatic, and sometimes probably gets up peoples' noses with his forthright presentation.

However, on this grinding of spindle moulder cutters in the workshop by the machinist or the craftsman on a bench grinder he is describing what used to be a fairly common practice. Right through the 1970s to the 1990s I worked in workshops that had a drawer or drawers with a wide selection of such cutters, some of which I'd ground myself.

We quite commonly ground just one cutter and then looked in the drawer for another already slightly heavier ground cutter that was then fitted in the block on the opposite side and set back from the profile of the newly ground cutter to act as a 'balance'. We didn't always get it just right, hence the tendency of spindle moulder operators to squat down under the table of the machine and do a quick start/stop test run of maybe 3 or 4 seconds just to listen and test if the machine ran sweetly … or vibrated like a good'un. If the latter, it was time to rethink and find an alternative ‘balancing’ cutter to get it all running smoothly.

I haven't ground any cutters for probably a bit more than eighteen or twenty years. The 30 mm bore blocks below, kept in my toolbox for primarily sentimental reasons, were probably new in the 1960s or 70s, but they haven't been fired up in anger in a long time. On the left is a Wadkin branded ‘Whitehill’ block, and to the right is a slotted collar type with a bearing at the top of the picture: this latter was normally used with straight cutters set to protrude to the same circumference as the bearing for template work, e.g., cabriole legs, etc. I no longer have any desire to grind a cutter(s) and set it (them) up in a block and run mouldings.

Health and safety regulations and practices have changed a lot over even my career. Having said that, things were a lot better in the 70s when I started than they were in earlier decades. I haven't seen a square head block spin since the early 80s, and I think they'd officially been made redundant or superseded about 30 or more years before that - they were truly fearsome bits of kit, in my opinion, and very common (normal?) in the early twentieth century. I did, however, just once see an old wood machinist with several damaged fingers, i.e., bits missing, set up a square head block over a dumpling and a ring fence of some sort to run a profile on a length of what I think was a compound curved stair handrail – I can’t recall for sure what it was now, but it certainly wasn’t simple and straight, hence the dumpling, and the risky moulding operation. I was probably about twenty years old, and it scared the hell out of me then, and thinking about it even now sends a bit of shiver down my spine, ha, ha. Slainte.

Below. Home ground single cutter below a 'Whitehill' block. Slotted collar block to right.

Below. Cutter fitted in 'Whitehill' block, as an example of typical appearance prior to a run, although the balancer is missing here.

 

[ColeyS1]

I use to love the challenge of grinding cutters to match specific moulds.

Sent from my SM-G900F using Tapatalk

 

[doctor Bob]

Interesting topic.
For me personally I'd have made the copy out of 3 pieces.
We have ground cutters in the past but in this modern age with strict HSE it's difficult in a commercial shop. Mainly as the cutters are secured much better and can't be tilted.

As others have pointed out, grinding is a little hit and miss. I'm a bit of a perfectionist and over the years I've come to realise that being 0.5mm out on a skirting dimension here and there is not the end of the world.

My biggest issue these days is sparks in the workshop, I get paranoid about an ember just smouldering away waiting to ignite properly at 9pm. Having lost one workshop through fire I'm very cautious these days.

 

[RogerS]

...
Hi Roger, I agree that Jacob can be quite dogmatic, and sometimes probably gets up peoples' noses with his forthright presentation.

....

I, and others, would call it rude, condescending and snide.

Moving on, thanks for the insight, Richard. And, of course, even before we had spindle moulders, they'd get out their warding files and hand-file a moulding plane to the profile - albeit slowly.

Bob's comment re sparks is a timely reminder.

Curious to know just how precise and how long it would take (if even possible) to create the profiles I am using. And, how easy to produce scribe and profile to accurately match each other. Coley - perhaps you'd like to comment ?

I can see that I'm not going to get any photographs from Mr Know-It-All...how convenient to have a 'workshop clearout'

 

[Trevanion]

Curious to know just how precise and how long it would take (if even possible) to create the profiles I am using. And, how easy to produce scribe and profile to accurately match each other.

It's totally possible, people have been doing it for the better part of a century. CNC grinders didn't always exist so it would have to be done by hand on a grinder.

I linked to this video in a separate thread yesterday which goes over grinding your own Euro Profiles:
[youtube]EpnTODGwMJA[/youtube]

I, and others, would call it rude, condescending and snide.

Keep it civil

 

[Jacob]

Curious to know just how precise and how long it would take (if even possible) to create the profiles I am using. And, how easy to produce scribe and profile to accurately match each other.

It's totally possible, people have been doing it for the better part of a century. CNC grinders didn't always exist so it would have to be done by hand on a grinder.

Longer than that. It's much the same as shaping a moulding plane blade or scratch stock, which are ancient - the Romans used them. Spindle blades thicker so take longer.
NB "scribe" profiles are strictly modern. Hand tool scribe methods different. Moulding planes strictly for long grain work. Personally I never bothered to make scribe profiles but did it the old way instead.
PS grinding blanks easier if you hold them with pliers to avoid burning your fingers. Glaziers pliers work well. An alternative is a saw kerf in the end of a bit of 1x2" with a clearance bevel so you can get it up to the wheel at an angle.

 

[Doug B]

...how convenient to have a 'workshop clearout'

I was surprised but very impressed, really freed up a lot of space, I was quite jealous :mrgreen:

 

[Jacob]

...how convenient to have a 'workshop clearout'

I was surprised but very impressed, really freed up a lot of space, I was quite jealous :mrgreen:

Glad you liked it Doug! New benching is so I can make the staircase on a long clear surface (7 metres!) and all the other rammel goes under. Have burned most of the odds and ends of cupboards. They seemed like a good idea but half of them were empty or full of junk.
I found the sample box but I can't be bothered to photo anything just to get ranting Roger off my back, better things to do. Can't be good for him all that huffing and puffing! Keeps me laughing though. :lol:
"I, and others, would call it rude, condescending and snide." :lol: :lol:

 

[Jacob]

Cutter collection. About 1/3 of these were made by me.
The rest were a job lot which I've never actually used, bought from someone on here a few years back including some machine made and some hand made.
Most of mine have one side aerosol painted grey as it takes a tidy pencil mark or scratch which doesn't get rubbed off. Some funny shapes where another profile has been added or part altered for one reason or another. They tend to get smaller as the years go by!
I spotted a pair of T&G cutters in the bought set which are double sided and notched as french cutters. I'll photo them separately later.
A lot of these look very peculiar but they make sense when you look at the finished product, which may have been past 2 or 3 profiles if complicated. e.g. ordinary glazing bars I'd do two passes - one for the moulding and another for the rebate.

Heres my new 7m benching, still cluttered, tidying in progress. About £150 worth of MDF, 2x3 and 2x4 inch CLS

 

[Jacob]

These images come out full screen on mine as I haven't reduced sizes. Is that OK on yours?

Box of samples - got more of these in various corners must sort them out!

Some of the bought set machine made and one little pair double ended T&G which are the most primitive spindle cutters of all; "french" cutters which go in a slot in the spindle (one at a time). The cut-out locates them so they can't fly out after they've been bolted down.

Big blanks, little cutters showing how tiny they go as they are re-used and re ground many time.

Blocks with unbalanced cutters (but balanced enough). The last one is serrated jaws for a serrated cutter, but plain cutters are held very well

I wouldn't advice anybody to try any of these things until they know what they are doing, and always use full guarding and two push sticks

 

[doctor Bob]

I wouldn't advice anybody to try any of these things until they know what they are doing, and always use full guarding and two push sticks

and don't answer the door in case it's HSE

 

[GarF]

Very interesting post. 2 part dental siloxane would probably be better for the moulds( or even alginate)

Silicone would work, but not a cheap option. Laboratory putty is cheaper as it doesn't have to be certified for use in the mouth and lots of craft suppliers carry this sort of material.

Alginate doesn't have sufficient dimensional stability if the impression is to be sent away anywhere. It shrinks and distorts (a lot) if it dries out

Both of the above would need some sort of rigid carrier to resist distortion as well.

In terms of capturing surface detail, plaster of paris is hard to beat, and cheap too. I suspect polyester filler is the most practical option- cheap, readily available, takes fine detail, dimensionally stable and reasonably resilient to rough handling in the post .
G

 

[Jacob]

I wouldn't advice anybody to try any of these things until they know what they are doing, and always use full guarding and two push sticks

and don't answer the door in case it's HSE

Strictly one man band stuff!
n.b. the push stick drawn in the HSE regs is not very good. The standard pattern with a much bigger mouth is far better and gives you better grip, both downwards and inwards.
Use two all the time, even with power feed have them handy. Your fingers need never go anywhere near the cutters. Brakes essential too. Without, a heavy block takes time to spin down and might not be noticed especially in a noisy shop

 

[deema]

Grinding my own cutters has been something I’ve considered doing. This thread has been really interesting and I’m impressed with the skills to grind cutters that some have. I find that most of the stuff I make can be produced with standard cutters, with only the odd one having to be custom made which I’ve always had done.

I think that an Armadillo Block would enable ‘home’ ground cutters to be used safely and meet the H&S requirements for maximum projection of the cutter to within 3mm without the need for limiters. I’d appreciate the views of those in the know.

 

[Jacob]

I don't know anything about Armadillo blocks but they look shockingly expensive and impractical to me.
I would have thought most normal blocks would hold diy ground cutters and matching limiters.
My answer to the prob is to use two push sticks and no limiters. The chances of me getting a cut are vanishingly small. The biggest hazard for me would be a running down block after the jobs done and not paying attention, but my machine has good auto brakes.
I'd say I'm safer than the regs - but I wouldn't want anyone to use my kit if they hadn't got the two push stick habit firmly engrained.