(sage)

06/28/09 10:48 AM

What tools do you need to build a Dob?

Hello,

I'm considering starting a dob project but only have a few very basic electric tools like a drill and a hack saw. I was browsing Home Depot yesterday and was surprised that some tools like drill presses and table saw weren't terribly expensive if you buy the smaller less "fancy" versions. My question is what tools would you recommend that I need for a project like building a dob? I'd purchase electric tools where it would make things substantially easier but would be fine with using hand tools where an electric one isn't absolutely necessary. I like to be able to take on other basic wood working projects as well down the road.

Thanks for the advice,

Tim

(Postmaster)

06/28/09 12:12 PM

Re: What tools do you need to build a Dob?

I used a table or contractor's saw, a small drill press, a router with a circle cutting jig, a planer and a jointer to build my smaller telescopes. The smaller of the two is almost entirely red oak, the larger one has a tube made of cherry while the base is Baltic Birch plywood. If you are going to build a Dob with the usual Sonotube, you can skip the planer and jointer for now, but if you plan to do any woodworking with hardwoods or rough sawn lumber, you'll need them.

Along with those tools, my tape measure, steel carpenter's sqaures, biscuit jointer and a variety of clamps were essential to the success of these telescopes. I finished both of them first with a small orbital sander, then a final pass by hand with a sanding block. I finished them with exterior Polyurethane applied with a high volume, low-pressure sprayer.

I've done a lot more with these tools than build a couple of telescopes. I've made bookcases, TV stands, even a full sized dresser from Brazilian Cherry, Lyptus and White Oak. While I'm no Norm Abrams, it works well and cost me at most a third of what a similar dresser would sell for new at a furniture store. The materials came to about 600 dollars, including the supplies such as glue, sandpaper and paint thinner. Woodworking is a good way to make gifts for family and friends too.

Taras

(sage)

06/28/09 12:35 PM

Re: What tools do you need to build a Dob?

Hello:

When I got started, I had very few tools. I had the usual hand tools, (screw drivers, wrenches, files, etc.). A hand held power drill is necessary, and a drill press is nice but not strictly necessary. Some kind of power saw is very useful, either a table saw, band saw, or a hand held circular saw. I have found a hand held jig saw to be very useful for cutting a whole lot of things, from aluminum tubes to the various round things that telescopes need. Definitely get a few bar clamps. I don't know what I'd do without them. That's about all that I use for my projects.

Cheers
Mike Connelley

John Carruthers

(Skiprat)

06/28/09 01:00 PM

Re: What tools do you need to build a Dob?

As well as the usual hand tools and a power drill, a medium sized router is a boon.

(professor emeritus)

06/28/09 01:27 PM

Re: What tools do you need to build a Dob?

A table saw will be quite helpful as well, but you can make a simple straight cutting jig for a hand held circular saw. If you use that and take your time, you can do really well with a hand held power saw.

I recommend the Rigid router at Home Depot that comes with a fixed base and a plunge base for $200. That is enough router for some pretty big jobs, and the fact that it has both bases makes it VERY versatile. You can make a circle cutting jig for it from plywood for a couple bucks, or free if you've got a piece laying around. I've used such a jig to cut the cage rings and a mirror blank for my current project, and they are perfect.

-Brian

(Carpal Tunnel)

06/28/09 02:25 PM

Re: What tools do you need to build a Dob?

For a minimum set: circular saw and guide, router, sabre saw, and hand drill. Plus the usual support items: tape measure, clamps (you can never have too many of those), sanding block, and an accurate square.

A better set would include a table saw, plate joiner, orbital sander, and drill press.

And that would be the order I would acquire them in. A skilled wood worker could add to that, but those are sufficient to build a basic scope.

(professor emeritus)

06/28/09 03:37 PM

Re: What tools do you need to build a Dob?

How could I forget an orbital sander?! I never knew how much I needed one of those until I got one as a gift. Sanding is no longer a chore!

-Brian

(Humble Megalomaniac)

06/29/09 10:51 AM

Re: What tools do you need to build a Dob?

If you want to know the absolute minimum tool set that will get you by, I built my 10" dob using nothing more than a jigsaw, a screwdriver, and a hand power drill. I built it in about three weekends on the front porch of an apartment.

It's workable and sturdy, but a long way from "craftsmanship".

The next most important tool to get, if I was going to build another one out of wood, would be a router, and a workbench.

(scholastic sledgehammer)

06/29/09 11:02 AM

Re: What tools do you need to build a Dob?

Quote:

If you want to know the absolute minimum tool set that will get you by, I built my 10" dob using nothing more than a jigsaw, a screwdriver, and a hand power drill.

I have barely started on my travel 8" project, but I am hoping to complete it with a drill as my only power tool, with no jigsaw or router. The trick is to find already formed circles for the alt bearings. My wife had an old round CD case that she was going to put on craigslist for free, so I grabbed it. The top and bottom were 3/8" particleboard circles of basically the size I needed. I sanded one side of each circle, glued them together with Titebond II (clamping with five tiers of bricks), and then cut the resulting 3/4" circle in half with a hand saw. Another source of wooden circles would be small round tables that one can find on craigslist for $10-20, or maybe even for free if one waits long enough.

(Post Laureate)

06/29/09 12:07 PM

Re: What tools do you need to build a Dob?

you could build an entire dob with just a router, a drill and a drill stand

(sage)

06/29/09 12:13 PM

Re: What tools do you need to build a Dob?

I built my first scope with a table saw, drill press and router.

(sage)

06/29/09 01:23 PM

Re: What tools do you need to build a Dob?

Thanks for all of the advice. I'm gonna use my existing tools as best as possible and buy additional tools as needed once i get into the project. Probably the only way to avoid buying equipment I won't use.

(scholastic sledgehammer)

06/29/09 01:24 PM

Re: What tools do you need to build a Dob?

hey dave i saw your ad in astronomics about "saurons other eye"...sweet man!!!

(professor emeritus)

06/29/09 06:04 PM

Re: What tools do you need to build a Dob?

Hi,

A decent drill press is pretty essential for drilling holes square to the surface. Get a machine vice which will CLAMP to the drill press table for holding small metal parts. Use the belt on the pulleys to give you the right speed for the drill or bit you are using.

A good handsaw is a lot safer than a table saw for cutting sheet material. (I use a few 4' lengths of sawn 3"x3" lumber on the floor as a stable bench. You have enough clearance for a jig-saw blade but those sort of saws give a wobbly cut and one side breaks out pretty badly.) A small Bosch cut-off circular saw is big enough for most Dobo projects. (You can cut 3" lumber from each side to get over its 1.5" depth limitation) It is lighter and more controllable than a 10" blade circular saw. I bought a cheap 10" circular saw first and returned it as not east to set and unwieldy.

A good small Router is pretty essential for cutting all the round parts you need for a telescope tube and Dobo or split ring mount. With a straight edge guide you can finish edges cut with a handsaw.

A few good quality chisels are useful as well. A diamond lap to sharpen them and act as a surface mill.

A good set square and 3' ruler make setting out as accurate as you need to be, along with a bit of Pythagoras geometry.

Cheers. Andrew.

(Carpal Tunnel)

06/29/09 08:20 PM

Re: What tools do you need to build a Dob?

Quote:

A good handsaw is a lot safer than a table saw for cutting sheet material.

One also has to use care using a table saw for small parts as I found out about four weeks ago. I was cutting a 2" x 3" piece of baltic birch. I made the mistake of having the small piece between the blade and the fence. Of course, the blade caught it and sent it right back at me at about 110 mph.

I took the hit just above the belt line on the right side. The resulting bruise was the size of a baseball and included at least 10 different colors, mostly indigo (and I don't bruise easily). Interestingly enough, it left me with a nice laceration and resulting scar (through my t-shirt) that my girlfriend says resembles the Ursa Minor.

(Humble Megalomaniac)

06/30/09 01:07 AM

Re: What tools do you need to build a Dob?

Quote:

hey dave i saw your ad in astronomics about "saurons other eye"...sweet man!!!

My ad??????

ETA: Oh -- you're talking about the current Astronomy Technology Today. Cool! I hadn't even seen it yet!

(Pounder of Brass)

06/30/09 08:11 AM

Re: What tools do you need to build a Dob?

Quote:

One also has to use care using a table saw for small parts as I found out about four weeks ago. I was cutting a 2" x 3" piece of baltic birch. I made the mistake of having the small piece between the blade and the fence. Of course, the blade caught it and sent it right back at me at about 110 mph.

I took the hit just above the belt line on the right side. The resulting bruise was the size of a baseball and included at least 10 different colors, mostly indigo (and I don't bruise easily). Interestingly enough, it left me with a nice laceration and resulting scar (through my t-shirt) that my girlfriend says resembles the Ursa Minor.

Ahh kickback! When it occurred on me, it was from me pulling the piece of material away from the saw blade on the left side and I angled it into the back of the blade. It hit me, did not leave a mark, but it hit the wall behind me

and I still cannot find where that piece of wood went.

I still love my tablesaw

I would use a handsaw, but I cannot cut straight if my life depended on it. In fact, I would love to use manual tools as much as I could because it is how they used to do it.

Jason

(Postmaster)

06/30/09 10:42 AM

Re: What tools do you need to build a Dob?

A table saw can throw wood at you with deadly force. I almost took a piece of red oak to the face, but instead it grazed my ear and hit the wall behind me. Had it hit me it probably would have smashed bone.

Taras

(Post Laureate)

06/30/09 02:07 PM

Re: What tools do you need to build a Dob?

all those old table saws are too dangerous to fool with.

ALL saws you use should have a splitter or better yet a riving knife directly behind the blade. if your saw cant be retrofitted, it really should be replaced (or turned into a disk sanding station).

you cant just be "really careful" (dont kid yourself!), wood is an unpredictable thing.

(sage)

06/30/09 08:58 PM

Re: What tools do you need to build a Dob?

I used a drill press, a router, and a table saw. I think it is possible to use a skill saw instead. I'd say the router and the drill are essential. Oh, and a sewing machine.

(Postmaster)

06/30/09 09:52 PM

Re: What tools do you need to build a Dob?

That incident was a result of my own lack of experience, since then I use feather boards and other tools that let me feed small pieces through the blade safely without kick back. Even with all the safety features put on these machines today, one can never be too careful if he wants to take all ten fingers and both eyes with him to the grave. I still have all of mine, and intend to keep it that way.

Taras

(Pounder of Brass)

07/03/09 12:24 AM

Re: What tools do you need to build a Dob?

I use a splitter at all times on my tablesaw. And I paid for a really nice blade (cost me 150.00) with carbide teeth and everything (A Woodworker II I believe). The key to safety on a table say is to pay attention where your fingers are, square your blade to the fence and miter slots, and a splitter (or a Riving knife). I use the Micro Jig full kerf splitter.

Jason

(scholastic sledgehammer)

07/06/09 08:06 PM

Re: What tools do you need to build a Dob?

Some of what you will need depends on what kind of Dob you intend to build.

If you build a Dob like John Dobson did with Sonotube and plywood you need fewer tools than if you build one like the type in the Kriege book.

The more sophisticated designs generally (though not necessarily) require more wood working tools.

Also, you may be surprised to find out how many of your neighbors and/or family members have nice tools sitting around waiting for you to borrow them.

(super member)

07/07/09 07:49 AM

Re: What tools do you need to build a Dob?

Buying power tools is a lot like buying astro-equipment....you could consider hand-held power tools to be sort of like EP's and stationary tools to be like dobs........a $35 EP (orthos excepted) will give you the same level of performance and satisfaction as a $35 jig-saw, for instance, while $150 will buy an EP or a tool that is a joy to use. Same applies to big tools, in that a $135 table saw is about equivalent to the $135 telescope over in aisle 9, $600 will buy you a very nice saw or scope, $1200 will buy you a pro-grade in either category. Keep in mind that the tool-head down the street could easily have $10 or 20K worth of toys in the shop.
One of the best ways to get the work done might be to ask that totally tooled up neighbor if he would like to swap a six-pack or bottle of his/her favorite beverage for an hour's time cutting parts out, another option might be to take an adult-ed woodworking course at your local tech school, and ask the instructor if you could build a scope as your project. There, you'll have a full shop, and valuable instruction on safe and efficient tool use.
If do-it-yourself is the way to go, a jigsaw, a random-orbit sander, and a cordless drill (and a patient approach) will get the job done.........if you want to tool up, even a small bandsaw is pretty close to laser-cutting technology, they excell at curves, and with a bit of practice do straight lines quite well, and a drill press not only drills holes nice and straight, they can be outfitted with sanding drums that create smooth, even edges. They are very useful tools, but also are pretty safe compared to jointers and table saws, both of which are quite capable of firing wood at you at warp factor 8, or changing your method of counting to ten in an instant. And always remember, quality takes time...........

(scholastic sledgehammer)

07/09/09 10:47 AM

Re: What tools do you need to build a Dob?

I built my 127mm strut dob with a screw driver and a dremel. And a good assortment of dremel bits.

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