need to drill a 2" hole 11" from edge - DONE with pictures

[CarvedTones]

and it needs to be perfectly perpendicular to the surface. I am working on an abandoned treadle lathe project and I may have finally stumbled on the main reason why it was abandoned. The center hole in the flywheel is not square to the surface. I expanded it concentrically to fit bearings without checking for squareness and made it worse. So now I am going to turn a hub to set the bearings into and then drill a big hole over the whole mess to set the hub into. But the only thing I have that will do it is a hole saw attachment for the drill that only approximates a true circle and would depend on me getting it square freehand. Anyone near by that can offer me a better solution? :eusa_pray

EDIT - Done! :eusa_danc Pictures and explanation of process further down. Many thanks to DaveD :eusa_clap for loaning me the tool and advising me on best practices to get accuracy and to others :eusa_clap who offered other solutions. Another NCWW success story! :icon_thum

 

[wayne]

Re: need to drill a 2" hole 11" from edge

you need to find someone with a cnc machine in your area. A cnc laser or router either one would do the job. The biggest problem with the laser would be having enough power for the thickness of the material needing the hole

 

[CarvedTones]

Re: need to drill a 2" hole 11" from edge

Thickness is about 3", actually slightly under. The wood is oak.

 

[wayne]

Re: need to drill a 2" hole 11" from edge

There should be someone in the Raleigh, Durham area with a shopbot. If no one on the forum has one some small independant cabinet shops would be a good place to look.

 

[wayne]

Re: need to drill a 2" hole 11" from edge

what is the diameter of the flywheel.It might be possible to chuck it up in a lathe if you could find one with a big enough capacity.

 

[scsmith42]

Re: need to drill a 2" hole 11" from edge

Chucking into a lathe would be your best solution.

You could screw a mandrel into the existing center hole, and use it to spin the flywheel in a lathe to true up the surface.

OR, you could chuck the flywheel in a lathe and bore out the center hole, and then attach a new center (or re-attach the original center after truing it up.

Is the flyweel wood or metal?

 

[Mike Davis]

Re: need to drill a 2" hole 11" from edge

It is red oak, Scott.

 

[scsmith42]

Re: need to drill a 2" hole 11" from edge

ok. IN that instance if a lathe is not available, use the appropriate sized forstner bit in a drill press, taking the time first to mark the exact center of the flywheel before drilling.

 

[eyekode]

Re: need to drill a 2" hole 11" from edge

There may be a couple ways to do it with a router. You could make a circle cutting jig (or use a Jasper jig if you have one). The center hole would have to be very accurately located but not necessarily perpendicular.

Another way to do it would be with a template. Make the template on the DP and then double stick tape (or brad nail) it to your real stock and use a top bearing pattern bit.

I am not sure you can get the depth of cut with a pattern bit but they make some pretty long solid cutters.

Another possibility is a shopsmith/horizontal boring machine (I don't have either so cannot help ).

 

[eyekode]

Re: need to drill a 2" hole 11" from edge

I just re-read your original post and now realize the center is gone. Another way you could do this is to make two squares that fit inscribed within the diameter of the flywheel. These squares will be only be ~15.56" on a side. Drilling to the center will be much easier. Each one could hold a bearing in the center. They could then be attached to the flywheel like hubs. Locating them correctly centered will be pretty easy if your square is truly square and it has the right length sides.

View image in gallery​

I guess there is one thing I am missing though... bearings on a flywheel?

 

[CarvedTones]

Re: need to drill a 2" hole 11" from edge

I just re-read your original post and now realize the center is gone.
(...)
I guess there is one thing I am missing though... bearings on a flywheel?

Cool idea (snipped out) on the center locating.

More background...

It is a wooden flywheel for a treadle lathe that someone else had started and abandoned (see this post for details if interested). Below it is just held in place with a dowel:

It is made of glued up boards. It is pretty obvious which face was down on a surface during glue up as one is flatter than the other, so I will use the flatter surface for reference to get a straight hole.

What I did after taking that picture was to plug the hole temporarily and then used a brace and bit with an adjustable size bit to make recesses for the bearings I got, which are a little under an inch and a half OD. I centered the recesses on the hole. I put bearings on a steel rod and pounded them in:

I had more trouble seating them than it seemed like I should, and it turns out it is because the original hole had a slight slant. As pictured, there is another issue I don't like anyway. The lathe needs to break down and it would be nice if the steel rod could easily be removed from the flywheel. If I make a slip in hub, that would work.

I made it worse trying to make little adjustments to correct it. I have a bunch of old epoxy left from a boat project and I can mix a batch of sawdust slurry and refill the entire cavity so there are reference points to drill.

It does not have to be perfect, but the belt would not stay in the groove with the wobble it has now.

 

[eyekode]

Re: need to drill a 2" hole 11" from edge

You are right, a picture is worth 1k words . I kept imagining a flywheel on the driven shaft. But this makes sense!
Salem

 

[Mike Davis]

Re: need to drill a 2" hole 11" from edge

If you have a router with a concentric base (the base is equidistant from the bit in all directions) Then cut a circle template to guide the base and route the center out for a new hub to fit. Set the bearings and shaft in the hub. Make a ring to hold the hub tightly in the flywheel.

 

[CarvedTones]

Re: need to drill a 2" hole 11" from edge

I think we are on the same page as far as the hub goes. I am confident that I can make that on the lathe with adequate precision.

I am a little concerned about routing inside a template. I am not sure the "flat" side is quite flat enough for that. If you look at the pictures above closely, you will see that the pcitures show both sides. The better side is the one where the hole is in the middle of a board. I would like to stay on the board as a reference if I use something sitting on the surface to drill. If I get access to a radial press, I will want that side down.

 

[Mike Davis]

Re: need to drill a 2" hole 11" from edge

You could mount a flat plate of aluminum or hardboard to the flat side as a base, shim as needed to make the surface square to the hub hole.

Ideally you would true the sides on a lathe for good balance.

 

[CarvedTones]

Re: need to drill a 2" hole 11" from edge

You could mount a flat plate of aluminum or hardboard to the flat side as a base, shim as needed to make the surface square to the hub hole.

Ideally you would true the sides on a lathe for good balance.

I do plan to trim it true by spinning it in place and clamping a board to use as a tool rest. If it was only a little off, I would do that now, but it is too far off. Because of the circumference, just being slightly off 90 makes a big difference out at the edge. I may have to recut the V also. I am beginning to see why you prefer starting from scratch over correcting someone else's mistakes. I am still pleased to have it.

 

[DaveD]

Re: need to drill a 2" hole 11" from edge

I have a drill guide for a portable drill that is similar to this one
http://pro.woodworker.com/images/ss/946-273.jpg
(If the picture link doesn't work go to www.pro.woodworker.com and search for item # 946-273)
except it doesn't swivel so the drill is automatically perpendicular to the base. I have a drill with a 3/8" chuck permanently attached on mine. Its one of those 'once every 3 years' tools.

In general it would insure 90 degrees (only as accurate as the tool itself). It could be fastened down to a bigger piece of material so it could be clamped to the wheel so it wouldn't move and then drill with a 2" forstner bit.

My forstner bit can only do about 3" depth though and without digging out the guide I don't know if the chuck will extend past the base. Its a 15 minute job to dig it out from where it is but I'd be willing to do that if you are interested. I'm just too lazy at the moment.

Another way would be to use a small table top drill press and rotate the base 180 degrees from its normal position and clamp the base to the wheel itself. That would require that you make sure the column is perpendicular to the wheel face before drilling. There are various ways to easily accomplish that measurement.

Be glad to help if you have further interest or want to borrow the guide.

BTW, how butchered up is the current hole? What is its current diameter?

What is the diameter of the actual shaft you want to use? Could you use face mounted pillow blocks (also called flange bearings) and creatively cover them with wood so they aren't as noticeable?

Just to keep thread complete here is actual guide. Can maybe squeeze out 3" drill depth

 

[CarvedTones]

Re: need to drill a 2" hole 11" from edge

Dave,

Thanks - yes I am interested. I think that would work for this project. The current arrangment is a 1/2" hole all the way through and shallow holes on each surface that are a little under 1.5". The idea was to mount the bearings on the shaft on either side of the wheel and kncok them into their tight fitting recesses. I had tested the recesses individually and the bearings fit very snugly, but on the rod I was having trouble seating them. It finally clicked that it was because they were not directly in line with each other; the 1/2" hole was not at 90 degrees. Anyway, I plan on filling those before I redrill.

I am going to make a hub instead not just because of the problem I ran into, but also because it will make the lathe easier to assemble/disassemble. I have high confidence in my ability to make a hub a consistent 2" diameter with the bearings fitting tightly and the shaft centered, so if I get a 2" hole at 90 degrees in the center of the wheel, I should be fine.

I will PM or email you to follow up...

 

[mburke911]

Re: need to drill a 2" hole 11" from edge

hi,
I have a grizzly Radial drill press you are welcome to use. Not sure if I have a 2" bit though. I have the G7946. I am in Cary as well.

Mark

 

[CarvedTones]

Re: need to drill a 2" hole 11" from edge

I haven't gotten up with Dave yet. I think he is going to loan me a bit and the drill/guide. I think I will go ahead and borrow both, then swing by your place and see if we can get it square enough on the table to use the radial press.

Thanks guys! I love this place...