Make your own speed increaser

[philbur]

I thought some of you guys might find this interesting:

http://www.hemingwaykits.com/acatalo...Increaser.html

Phil

[Regnar]

Neat. You might also find this months Home Shop Machinist interesting too. They take a dremel tool and make a spindle insert for it to run

[ataxy]

Neat. You might also find this months Home Shop Machinist interesting too. They take a dremel tool and make a spindle insert for it to run

i am not sure but wouldn't this kill your dremel pretty fast.

[Oldmanandhistoy]

i am not sure but wouldn't this kill your dremel pretty fast.

Would not have to be a Dremel could be a small router

[Regnar]

I don't know truthfully. A lot of guys use it in the diy section for normal wood routing with the bit chucked right into the spindle. If you where to use a v belt I don't think the strain would be on the dremel but the spindle itself. He used a timing belt so if the bit gets stuck or jammed well the dremel stops so that cant be good.

In all reality hoss design is the easiest (for me at least) and is more powerful then a dremel. A new trim router just came out that I am waiting for some reviews on before I pick up one. Its called the Marvel 40 put out by MLSC. It allows for 1/4 and 1/8 bits as both collets are included in the kit. Nice round body unlike the Rotozip. The only negative is that it is not variable speed. You could do the setup like the home shop machinist and use a Rigid Trim router which comes with a life time warranty just I would remove the timing pulley before I took it in for service. Rigid does have the variable speed just no 1/8 collet.

[philbur]

Does the insert have its own bearings or is the Dremel driving the mills spindle? Does the article discuss the effect of the load on the Dremel spindle bearing due to belt tension and on the motor due to start-up inertia? The Dremel is kinda under-powered as is, driving another set of bearings as well will not leave much umph for the cutting tool. What's the advantage? Why not just use the Dremel direct?

Phil

Neat. You might also find this months Home Shop Machinist interesting too. They take a dremel tool and make a spindle insert for it to run

[P Riedie]

I thought some of you guys might find this interesting:

http://www.hemingwaykits.com/acatalo...Increaser.html

Phil

It was also appeared in Model Engineers Workshop and if you study the design it not much good.
It has one ball race at the bottom to support the spindle but no top support at all only one pinion running round the sun wheel so all it wants to do is push the spindle off centre.

There was no thought put into this as using stock items he gets a 3:1 reduction but in the opposite direction. Using the same stock items and driving them differently, hold the ring gear instead of driving it, means that it's possible to get 4:1 reduction and still travel in the correct direction.

The concept is good, after all these are made commercially and are very expensive but the design is flawed.

PR.

[Regnar]

The dremel spins the insert and not the mills spindle. Doesnt say the effect on the dremel itself but the author did have it mounted off to the side before and said that the dremel alone was not rigid enough for fine milling.

[philbur]

Thanks for that PR,

I guess the "expensive" comes in when you decide to use precision spindle bearings and spur gears good for high rpms.

Phil

It was also appeared in Model Engineers Workshop and if you study the design it not much good.
It has one ball race at the bottom to support the spindle but no top support at all only one pinion running round the sun wheel so all it wants to do is push the spindle off centre.

There was no thought put into this as using stock items he gets a 3:1 reduction but in the opposite direction. Using the same stock items and driving them differently, hold the ring gear instead of driving it, means that it's possible to get 4:1 reduction and still travel in the correct direction.

The concept is good, after all these are made commercially and are very expensive but the design is flawed.

PR.

[philbur]

Ya, I guess the Dremel spindle bearings are a bit sloppy for precise work. The Proxxon is easier to mount and seems to have more controlled spindle bearings. I guess if you must use a Dremel then some problems are over-come, but I think possibly others are introduced. Did the author say how well it worked?

Phil

The dremel spins the insert and not the mills spindle. Doesnt say the effect on the dremel itself but the author did have it mounted off to the side before and said that the dremel alone was not rigid enough for fine milling.

[LeeWay]

Hmm. I have the little ridgid trimmer mounted next to my spindle. It does have a little up and down drift as well as runout, but it works okay in aluminum as is.
I am using 1/4" bits though, so it's not ultra precise. Doesn't need to be in my application.

It seems it might be easy to get this to turn a small air die grinder if you can find one with little play, but then you could do away with the router and just use air.
All the ones I have seen have just as much play as the router.
They are louder using air, but the sell air motor mufflers too. That makes them a bit more bearable.

[Regnar]

No he didnt mention how well it cut and in fact doesnt even show a picture of it cutting or what it cut. I think this all comes in the next magazine seeing this is part 1 of 2. Im put off by it because there is a awful lot of lathe work and when you have no lathe well you cant do lathe work.

Here is the parts of it so that you can get an ideal of what is going on.