Advice for Dado and Groover sets

[ddichiera]

Hi everyone, my first post here, although I have done some searching on the forum.

I have a practical question about the use of Dado and Groover sets on machines.

I have two saws, a Scheppach 4010 table saw (aly table), an Elu 1251 (e.g. Dewalt 720) Radial Arm Saw and I also have a 16mm bore Dado set for the RAS (along with the special guard). My question is about mounting the blades on the arbours.

If we take the RAS first, the spindle diameter is 5/8 or 16mm and the Dado set bore is the same, but the original blade has a 30mm bore with the difference being made up by a boss on one of the two flanges (or washers) used to fasten the blade to the motor arbour. How do I mount the Dado set to this arbour?

Secondly, the Scheppach table saw. When I first bought it, I ordered it with a Freud Dado set and was supplied a set reamed out to 30mm. When I went to fit it, I very quickly realised it wasn't going to work and returned it. Fortunately it was the supplier's mistake and they gave me a refund. Scheppach supply a very expensive groover set for this saw which seem to me to just be a Spindle Moulder groover set with a 30mm bore (I might be wrong). In any case the same problem seems to apply here, how does one mount a thick groover when the 30mm bore of the original blade is accounted for by the boss (or built in spacer) on the flange?

I like Karl's setup in message "dado-cutters-t445" (sorry I don't have permission to post links)

Thanks in advance for your help.

Dominic

 

[9fingers]

I use a 30mm freud dado set on my DW1753 RAS (almost certainly the same spindle as yours) simply by fitting one of a selection of spacers onto the 5/" shaft. Each spacer is 30mm OD and supports each part of the dado set. The spacer length is chosen to not protrude as far as the clamping flange. My spacers are home made from mild steel.

I don't know the Scheppach saw in detail but I would have thought that a similar arrangement might work.

Note that very few saw supplied in the EU are equipped to mount dado heads so make sure what ever improvisation/modifications you make are sound and use a suitable insert in the table.

HTH

Bob

 

[Steve Maskery]

Well I'm not familiar with the specifics of your machine, but if I understand you correctly, I think the answer is "with difficulty". You may have to change the spindle as well as the flange. I know that the Jet has two different spindles, a 30mm for Europe and a 5/8 for the US, and the Excalibur, which several of us here have, has a short 30mm as standard and an optional 5/8 longer one for dado use (although that also limits depth of cut at full tilt). Certainly with the Excalibur and I'm pretty sure with the Jet, the flanges are not stepped, any difference in bore is made up with bushes instead.

I think you may have a problem!
S

 

[jasonB]

DW radiual arm saws need a flange without any stepped face and teh dado will fot straight onto the shaft

I think the body of the groover for the saw is narrow in the middle so it can be mounted on a standard length spindle, its not as thick as a spindle moulder one. So your dado won't fit the standard arbor

J

 

[misterfish]

Hi and welcome Dominic.

I've got a Dewalt 1251 and have a dado backing flange for use with the dado set. This picture shows them both.

.

I bought my backing flange from one of the tool spares suppliers but they no longer list the item. However, they do get offered from time to time on Ebay - often as part of the Dewalt 8 inch dado set or moulding head - but not with the 6 inch dado!.

Misterfish

 

[powertools]

You need a washer with same thickness as the height of the boss. a 30mm hole and an outside diameter the same as the flange. This then fits on the flange over the boss giving you a flat surface on the flange for the dado set to sit against.
The dado set then fits the 16mm arbour as it should.

 

[ddichiera]

Thanks for your replies.

misterfish, you photo is very enlightening. May I ask the following questions:

1. Are the flange and bush shown in the correct orientation except the flange should be on the left and bush on the right?
2. Is there a recess in the flange to accept the smaller diameter of the bush (which would allow for different thickness setups)?
3. Is the smaller diameter on the bush 30mm to accept a large bore set?

If so, as I have a 16mm set, I could just buy a spare normal flange, have the boss machined off and use that with the original left hand flange. I don't know if there is enough arbour left to accept the nut though.

BTW: It's interesting to hear that some are using bushes to make up the difference. I had considered that option but felt I could guarantee the flanges wouldn't tighten on those and not the blades and I felt uncomfortable with that.

 

[powertools]

You could machine off the boss on the flange you have got and then use reducing bush on your saw blades.
My DW125 RAS does not have a boss on the flanges and takes 16mm arbour blades all with reducing bushes.
Of cause before you do anything you need to make sure that the arbour will have enough thread left to secure the dado set.

 

[misterfish]

The two flanges are alternative inner flanges that go on the arbor next to the motor. You should already have the left hand version for use with normal 30mm bore blades as it's the standard one that comes with the saw. As you can see the dado flange is not so wide.

I'll do a couple of pictures later to show the set up I use with both sets of blades.

Misterfish

 

[scholar]

Hi

I can only speak for the Scheppach 4010 saw. I have the 8-15mm adjustable slot cutter set which works very well. It is 200mm dia and Scheppach list it as an accessory for both the saw and the spindle moulder. On the saw you get a 50mm depth of cut. I do recall it was not cheap...

You do need the aluminium table insert to use this - this comes with a special locking nut that has a 30mm inside collar which holds the outer half of the cutter set.

I guess that the size of cutter that can be used is a function of the length of the arbour, the width of the slot in the table and any limitation on the loading on the motor braking etc (this latter point is quoted often in this regard, but I guess it will depend not just on the size of tool, but the overall mass). Anyway, as Scheppach are not backward in offering accessories, I guess they offer the maximum that the machine is designed to take.

Perhaps a more economical proposition would be to find a (cheaper) alternative cutter set of suitable dimensions and get the Scheppach table insert and locking nut (NMA would help you on the details of what is needed for your saw).

Out of interest, I have had a look at my setup - the cutter set is 8mm thick without spacer shims, and 15mm with all shims loaded; this leaves no extra arbour length projecting beyond the nut, so 15mm is the maximum width you can have using the Scheppach nut.

Also, you really should consider getting the overhead SUVA guard and extraction hood (of course the extraction is redundant if you are doing a housing cut, but the guarding is the key) I still have this on the list to sort out, but I do approach the machine even more cautiously than usual when using this setup.

Hope that helps

Cheers

 

[ddichiera]

misterfish Thanks, since my last post I found another of your excellent photos on this post elu-radial-arm-saw-t34870.html after which the penny dropped. Helpfully you also gave the width as 28mm and 16mm. In the absence of finding one on eBay, I don't see why I couldn't just have one machined up. I don't have access to the saw right now, but I seem to remember the inner flange doesn't have a flat to match the arbour.

scholar Wow 200mm diameter! I had thought to buy a Whitehill or similar for my Scheppach HF 33 spindle moulder and also use it on the 4010, but now I'm in two minds. Whitehill's biggest is 160mm and I don't think I could get the 200mm Scheppach inside the spindle moulder fence housing. Your explanation of the 30mm inside collar is very helpful, I think I'll start by trying to chase that up as a spare and see how I go.

BTW does the cutter come with the table insert or do I have to fork out another £70+ for that as well?

 

[jasonB]

Just watch the speeds if fitting a smaller dia groover into the saw as it may not have a fast enough perifferal speed. Also if its heavier than the scheppach one it may overload the brake

J

 

[misterfish]

No reason at all why you couldn't get one machined up to your specifications. If you want I can measure the dimensions accurately and do close ups. Let me know if that will help.

Misterfish

 

[ddichiera]

No reason at all why you couldn't get one machined up to your specifications. If you want I can measure the dimensions accurately and do close ups. Let me know if that will help.
Misterfish

That would be the Bee's Knees

This topic has been raised so many times, I'm sure others would also appreciate it.

Thanks.

 

[misterfish]

First the pictures

Standard flange configuration

Dado flange configuration

Dado flange close ups

Flange dimensions - apologies for total lack of correct technical terminology

Max diameter - 40mm
Diameter of stepped bit - 25mm
Bore - 16.00. (The keyway is not used)
Depth - 16.16mm (with wide part 9.08mm and stepped narrow bit 7.08mm
The depression on the surface that goes against the blade is 1.5mm deep at maximum

If this is not enough I'll try and draw it with measurements added on the drawing - I haven't got either software or skills to do a computer scale drawing.

Misterfish

 

[9fingers]

I can make the small dado flange without keyway if anyone wants one. 1 brown beer voucher each to include postage in UK

Requests by PM please

Bob

 

[powertools]

Can someone explain why the best option is not to remove the boss from the washer and use reducing bushes on the saw blades.
This option gives far more support to the dado set.

 

[ddichiera]

They are great photos and measurements.

The difference in diameter between the inner and outer flanges intrigues me (it's what confused me at first). I would have thought that ideally they should match, (as per the originals) in order to maximise grip on the blades, but I guess not.

Thanks once again.

Now to have one machined up.

 

[misterfish]

Can someone explain why the best option is not to remove the boss from the washer and use reducing bushes on the saw blades.
This option gives far more support to the dado set.

The dado flange being shorter/narrower allows the fitting of a wider dado stack. Also when using the dado flange you have to use a dado blade guard - i use a modified version of http://tooltray.com/DeWalt-Saw-Accessor ... m-Saws.htm

Misterfish

 

[ddichiera]

I use a modified version of http://tooltray.com/DeWalt-Saw-Accessor ... m-Saws.htm
Misterfish

Oh Misterfish, you've done it again. I have the guard but I have no idea how it's going to work. Might I trouble you for a photo of the mod?