calculating the best size router bit and bushing for project

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SMALMALEKI

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I need to drill series of holes 30 mm and 22 mm. I was planing to use a press drill to drill them but I was advised against using a small press drill as the diameter of holes on hardwood will put far more pressure than the drills can handle.
Therefore I am planing to use a router with jig and guide bush.
Can I make the hole with one jig ( to avoid risk of missing the centre on changing the jig) and two different size of router bits with jig?

Thank you in advance for your support and advice.
 

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You could speak to a cutter grinder with a view to him altering a standard router cutter to give the stepped shape required with one cutter.
Alternatively you can solve the problem of locating the different sizes of jig by having an outer template which can be clamped to the workpiece and a series of interchangeable centrepieces which drop in and guide the bush and a single size cutter.
The method selected really depends on how manny holes you wish to drill.
Mike.
 
Drill press much easier than a router. Should be able to do it with good quality Forstner bits, but slowly and keep pulling it out to clear dust, especially shavings wrapping over the cutting edge. If it's very hard wood then might need a quick sharpening of the cutting edges at intervals.
Yes you could do it in steps as forstner bits don't rely on centre point for alignment.
You could even do it with spade bits if high precision not essential but only in one stab with frequent sharpening required.
 
I think this is only the second time I've agreed with Jacob. :lol:
A drill press can cut any sized hole you can fit the bit into it. i have drilled 42 mm holes on my very cheap bench drill press, using a tank cutter through 10 mm mild steel!
Little and often are the key words. let the bit do its work, dont force it down into the piece.
And the larger the bit, the slower the cutting speed or then you WILL stall the press.

Securely clamp the work piece in place.
Start with the largest drill / forstner bit and use minimal pressure lifting it to clear the swarf very often.
Then swap to the next smaller bit. The centre point should line up with the larger centre point.

Make sure you have a sacrificial piece of wood underneath so that the final cut does not tear out the wood edge.
 
Mike Jordan":hsdjrfom said:
You could speak to a cutter grinder with a view to him altering a standard router cutter to give the stepped shape required with one cutter.
Alternatively you can solve the problem of locating the different sizes of jig by having an outer template which can be clamped to the workpiece and a series of interchangeable centrepieces which drop in and guide the bush and a single size cutter.
The method selected really depends on how manny holes you wish to drill.
Mike.


Hi Mike

Thank you for your advice. I am only drilling 4 holes at this stage. I like the interchangeable inner template. But as the others said it might be easier to use a bench drill. I will continue to experiment and learn.

Saeid
 
Jacob":3j3whbuv said:
Drill press much easier than a router. Should be able to do it with good quality Forstner bits, but slowly and keep pulling it out to clear dust, especially shavings wrapping over the cutting edge. If it's very hard wood then might need a quick sharpening of the cutting edges at intervals.
Yes you could do it in steps as forstner bits don't rely on centre point for alignment.
You could even do it with spade bits if high precision not essential but only in one stab with frequent sharpening required.
Hi Jacob

It is reassuring to receive encouraging advice from experienced members. I will get a bench drill and try it with Forstners. There are pretty confusing items in the market. I have seen exactly the same Forstner kit with two different brand name and as unbranded. That’s the only kit which has 30mm Forstner in it.
Any advice on bench drill??



Saeid
 
sunnybob":17p4prry said:
I think this is only the second time I've agreed with Jacob. :lol:
A drill press can cut any sized hole you can fit the bit into it. i have drilled 42 mm holes on my very cheap bench drill press, using a tank cutter through 10 mm mild steel!
Little and often are the key words. let the bit do its work, dont force it down into the piece.
And the larger the bit, the slower the cutting speed or then you WILL stall the press.

Securely clamp the work piece in place.
Start with the largest drill / forstner bit and use minimal pressure lifting it to clear the swarf very often.
Then swap to the next smaller bit. The centre point should line up with the larger centre point.

Make sure you have a sacrificial piece of wood underneath so that the final cut does not tear out the wood edge.

Hi Sunnybob

Thank you for your reply. Very good practical points you mentioned. I’ll try them and post the outcome here.

Saeid
 
SMALMALEKI":2mqj6efw said:
......
Any advice on bench drill??
Saeid
Mines a cheap Nu Tool. £50 2nd hand on ebay. It's quite well made and accurate, plenty good enough for woodwork. They all look the same from the far east, probably made the same place but with different brand names etc
They are simple devices, not much to go wrong with them even if cheap.
 
If you're going to buy Forstner bits, may I recommend getting them from https://www.wealdentool.com/

They're not too expensive but infinitely better and easier to use than cheapo ones sold in screwfix/toolstation etc
 
Hi
Just to give you an update. I took up the advice from the forum and decided to test it.

I bought a set of Forstners from Screwfix ( not worth the paper they printed the receipt on) and used a HSS 22mm drill. The results was not satisfactory ( I used a hand hold wireless drill). The bushing was 21.3mm instead of 22mm.
I used beechwood as it is what I have to drill for my project.

So I took an old 22mm Spade and a file. It resulted in a 21.3mm spade.
The right hand hole is the final result.

Thank you all for your advices.
 

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We were all talking about a drill press. You have no chance being that accurate with a hand held drill.
 
sunnybob":25jftag6 said:
We were all talking about a drill press. You have no chance being that accurate with a hand held drill.
Hi Sunnybob

I know you were talking about bench drill. I don’t have one yet but having drilled the hole by hand I am sure bench drill will do the job.

I am researching bench drills before buying one. Any advice on buying one?

Regards
Saeid
 
sadly, all cheap bench drills are cheap for a good reason.

I bought the axminster, but really cant recommend it unless you have engineering and electrical skills to make it fit for purpose.
You will find a lot of people buy 50 year old drills and do them up cosmetically because even at 50 years they are usually better than new.

So no, I cant recommend one, but without doubt, AFTER all the farting around to make it do what it said on the box it should do in the beginning, they are a very useful tool.

good luck in your search. :roll:
 
sunnybob":1ohnzrui said:
sadly, all cheap bench drills are cheap for a good reason.
.......
Yes, but may well be good enough for woodwork. Mines a NuTool. £50 ebay. Very precise, solid, heavy and easy to use, but I guess it wouldn't last long in a metal work or engineering workshop. It's got 12 speeds via 3 pulleys, which seems excessive - 4 would do.
NB Not ideal but large Forstner bits work in a heavy hand-held drill with 2 handles, but not easy in a light-weight little one.
 
Jacob":374ws3x0 said:
sunnybob":374ws3x0 said:
sadly, all cheap bench drills are cheap for a good reason.
.......
Yes, but may well be good enough for woodwork. Mines a NuTool. £50 ebay. Very precise, solid, heavy and easy to use, but I guess it wouldn't last long in a metal work or engineering workshop. It's got 12 speeds via 3 pulleys, which seems excessive - 4 would do.
NB Not ideal but large Forstner bits work in a heavy hand-held drill with 2 handles, but not easy in a light-weight little one.


Hi Jacob

I have been monitoring eBay and Facebook for bench drills but have not seen anything to appeal at first glance the new ones look the same with different name logo printed on them.
Does 1 or 3 year warranty worth going for brand new ones?

Best regards
 
SMALMALEKI":31nuh69w said:
....
Does 1 or 3 year warranty worth going for brand new ones?

Best regards
They are simple devices, not much to go wrong and like a lot of amateur woodwork kit, often don't get a lot of use.
£50 to £100 on 2nd hand should be safe but you never know!
In fact my £50 one had a fault - a loose allen grub screw which was no prob once identified. I think the seller thought he was selling a dud and let it go cheap.
"Trade" models tend to be much the same as craft models but will have bigger motors (useful for your wide Forstner cutters) and presumably better bearings and other details to take the strain.
The big plus with 2nd hand is you can usually get your money back or even make a profit if it's in good order and you want to trade up to a better model.
 
Jacob":uppel7b9 said:
sunnybob":uppel7b9 said:
sadly, all cheap bench drills are cheap for a good reason.
.......
Yes, but may well be good enough for woodwork. Mines a NuTool. £50 ebay. Very precise, solid, heavy and easy to use, but I guess it wouldn't last long in a metal work or engineering workshop. It's got 12 speeds via 3 pulleys, which seems excessive - 4 would do.
NB Not ideal but large Forstner bits work in a heavy hand-held drill with 2 handles, but not easy in a light-weight little one.
Mine cost 200, and was not usable from the box. It could not even be assembled because the bolts to fix the shaft to the base were a different size to the holes threaded into the base. The NVR switch was wired backwards, the table is the wrong size as the hole in does not line up with the chuck, and there were a few other completely unacceptable quality control failures.
You pays yer money and you takes yer chances.
 
sunnybob":37d1oo07 said:
Jacob":37d1oo07 said:
sunnybob":37d1oo07 said:
sadly, all cheap bench drills are cheap for a good reason.
.......
Yes, but may well be good enough for woodwork. Mines a NuTool. £50 ebay. Very precise, solid, heavy and easy to use, but I guess it wouldn't last long in a metal work or engineering workshop. It's got 12 speeds via 3 pulleys, which seems excessive - 4 would do.
NB Not ideal but large Forstner bits work in a heavy hand-held drill with 2 handles, but not easy in a light-weight little one.
Mine cost 200, and was not usable from the box. It could not even be assembled because the bolts to fix the shaft to the base were a different size to the holes threaded into the base. The NVR switch was wired backwards, the table is the wrong size as the hole in does not line up with the chuck, and there were a few other completely unacceptable quality control failures.
You pays yer money and you takes yer chances.
At least if it's second hand you can see it working. Or with ebay you are fairly well guaranteed if there's a fault - I've had a few refunds, sometimes not even wanting the faulty kit back - not worth their paying the carriage, mending it and trying to sell it all over again.
 
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