Need Info On Reamers

[DonMorrisey]

I'm trying to figure out how and where to buy reamers. I need to
create some 5/8" and 1/2" holes in ultra high molecular weight
polyethylene blocks for my control system. The aileron push tubes
slide thorugh the blocks and the aileron actuators mount in the blocks
as well. The mounting component of my aileron actuator is 5/8", so
when buying the .6250" reamer is that already slightly oversized? I
have been told the holes should be oversized by .002". I have looked
for reamers on line but don't know if what I'm buying is the right
size, there is little or no description for them.

Can someone tell me what I should look for in buying these tools and
where may be the best place to do so?

Thanks. Don

[[email protected]]

DonMorrisey wrote:
> I'm trying to figure out how and where to buy reamers. I need to

Here is about the best source for reamers:
http://www1.mscdirect.com/CGI/NNPDFF?PMPAGE=178&PARTPG=N2DRVSH&PMT4NO=16835364&PMITEM=02239036&PMCTLG=00&PMT4TP=*LTIP

You might have to cut and paste to get it to work. Scroll to the bottom
of the page and you will find the adjustable reamers. These guys are
quick on shipping. There have been times that I have ordered things in
the afternoon and had them show up in the morning UPS delivery.

If the blocks are very thick, a .002" oversize hole is pretty tight.
You will have to make doubly sure that everything is in perfect
alignment so that there is no binding of the tube.

Craig C.

[Ed Sullivan]

On 20 Jan 2007 18:40:24 -0800, "DonMorrisey" >
wrote:

>I'm trying to figure out how and where to buy reamers. I need to
>create some 5/8" and 1/2" holes in ultra high molecular weight
>polyethylene blocks for my control system. The aileron push tubes
>slide thorugh the blocks and the aileron actuators mount in the blocks
>as well. The mounting component of my aileron actuator is 5/8", so
>when buying the .6250" reamer is that already slightly oversized? I
>have been told the holes should be oversized by .002". I have looked
>for reamers on line but don't know if what I'm buying is the right
>size, there is little or no description for them.
>
>Can someone tell me what I should look for in buying these tools and
>where may be the best place to do so?
>
>Thanks. Don

You might check McMaster-Carr online catalog

[Bob Upp]

You can reference standard drill size "probable oversize" which would
apply to holes in metals but I work with black polyethylene parts a lot
in my ultra-lights and helicopters and if I used it for your purpose I
would just use a 1/32 or 1/64 oversize drill. From my experience a .6250
drill will leave an undersize hole in polyethylene and a reamer would
just push polyethylene aside unless the edge is ground and relieved
especially for pliable material. Instead of wasting money for reamers I
would just drill test holes and then check for the clearances you need.
My guess is that a 41/64 drill will give you a probable hole of .6407
inches in aluminum and somewhat less in polyethylene, maybe .630 or so.
I suspect the drill speed will effect finish hole size as well and you
could experiment for finish hole size this way too.
Again, in metals and hole sizes of around 1/2" to 3/4" will be roughly
..004 oversize and in plastic probably less. I say drill some test holes
and try them out.




"DonMorrisey" > wrote in message
oups.com...
> I'm trying to figure out how and where to buy reamers. I need to
> create some 5/8" and 1/2" holes in ultra high molecular weight
> polyethylene blocks for my control system. The aileron push tubes
> slide thorugh the blocks and the aileron actuators mount in the blocks
> as well. The mounting component of my aileron actuator is 5/8", so
> when buying the .6250" reamer is that already slightly oversized? I
> have been told the holes should be oversized by .002". I have looked
> for reamers on line but don't know if what I'm buying is the right
> size, there is little or no description for them.
>
> Can someone tell me what I should look for in buying these tools and
> where may be the best place to do so?
>
> Thanks. Don
>

[Dan[_2_]]

Ed Sullivan wrote:
> On 20 Jan 2007 18:40:24 -0800, "DonMorrisey" >
> wrote:
>
>> I'm trying to figure out how and where to buy reamers. I need to
>> create some 5/8" and 1/2" holes in ultra high molecular weight
>> polyethylene blocks for my control system. The aileron push tubes
>> slide thorugh the blocks and the aileron actuators mount in the blocks
>> as well. The mounting component of my aileron actuator is 5/8", so
>> when buying the .6250" reamer is that already slightly oversized? I
>> have been told the holes should be oversized by .002". I have looked
>> for reamers on line but don't know if what I'm buying is the right
>> size, there is little or no description for them.
>>
>> Can someone tell me what I should look for in buying these tools and
>> where may be the best place to do so?
>>
>> Thanks. Don
>
> You might check McMaster-Carr online catalog

In Mcmaster look for "oversize reamers." I make model steam engines
and buy 99% of my reamers from Mcmaster.

Dan, U.S. Air Force, retired

[[email protected]]

I'll second the non-use of reamers here. Just drill 'em, and remember
you have the choice of numbered, lettered and metric drills to get the
size hole you need. Temperature also seems to play a big part in how
much spring back you get drilling holes in this kind of material.
Experiment :-)
==================
Leon McAtee

Bob Upp wrote:
> You can reference standard drill size "probable oversize" which would
> apply to holes in metals but I work with black polyethylene parts a lot
> in my ultra-lights and helicopters and if I used it for your purpose I
> would just use a 1/32 or 1/64 oversize drill. From my experience a .6250
> drill will leave an undersize hole in polyethylene and a reamer would
> just push polyethylene aside unless the edge is ground and relieved
> especially for pliable material. Instead of wasting money for reamers I
> would just drill test holes and then check for the clearances you need.
> My guess is that a 41/64 drill will give you a probable hole of .6407
> inches in aluminum and somewhat less in polyethylene, maybe .630 or so.
> I suspect the drill speed will effect finish hole size as well and you
> could experiment for finish hole size this way too.
> Again, in metals and hole sizes of around 1/2" to 3/4" will be roughly
> .004 oversize and in plastic probably less. I say drill some test holes
> and try them out.
>
>
>
>
> "DonMorrisey" > wrote in message
> oups.com...
> > I'm trying to figure out how and where to buy reamers. I need to
> > create some 5/8" and 1/2" holes in ultra high molecular weight
> > polyethylene blocks for my control system. The aileron push tubes
> > slide thorugh the blocks and the aileron actuators mount in the blocks
> > as well. The mounting component of my aileron actuator is 5/8", so
> > when buying the .6250" reamer is that already slightly oversized? I
> > have been told the holes should be oversized by .002". I have looked
> > for reamers on line but don't know if what I'm buying is the right
> > size, there is little or no description for them.
> >
> > Can someone tell me what I should look for in buying these tools and
> > where may be the best place to do so?
> >
> > Thanks. Don
> >

[Highflyer]

"DonMorrisey" > wrote in message
oups.com...
> I'm trying to figure out how and where to buy reamers. I need to
> create some 5/8" and 1/2" holes in ultra high molecular weight
> polyethylene blocks for my control system. The aileron push tubes
> slide thorugh the blocks and the aileron actuators mount in the blocks
> as well. The mounting component of my aileron actuator is 5/8", so
> when buying the .6250" reamer is that already slightly oversized? I
> have been told the holes should be oversized by .002". I have looked
> for reamers on line but don't know if what I'm buying is the right
> size, there is little or no description for them.
>
> Can someone tell me what I should look for in buying these tools and
> where may be the best place to do so?
>
> Thanks. Don
>

Or, if not MacMaster Carr, Check MHC online. ( Manhattan Supply Company )
They do an unbelieveable job of stocking every thing in their catalog. I
once ordered a six foot long length of 1 1/4 inch ACME threaded rod, with
nuts. It arrived the next day by UPS Ground!

Highflyer
Highflight Aviation Services
Pinckneyville Airport ( PJY )

PS: Note, the Pinckneyville 2007 Flyin is coming up May 18, 19, and 20!
Plan now so you don't miss it. :-)

[Maxwell]

"DonMorrisey" > wrote in message
oups.com...
> I'm trying to figure out how and where to buy reamers. I need to
> create some 5/8" and 1/2" holes in ultra high molecular weight
> polyethylene blocks for my control system. The aileron push tubes
> slide thorugh the blocks and the aileron actuators mount in the blocks
> as well. The mounting component of my aileron actuator is 5/8", so
> when buying the .6250" reamer is that already slightly oversized? I
> have been told the holes should be oversized by .002". I have looked
> for reamers on line but don't know if what I'm buying is the right
> size, there is little or no description for them.
>
> Can someone tell me what I should look for in buying these tools and
> where may be the best place to do so?
>
> Thanks. Don
>

You might want to consider adjustable reamers Don.

http://wttool.resultspage.com/search?p=Q&ts=custom&uid=956095168&srid=S9-2&nodecode=true&af=&do=search&do=search&w=adjustable+reamers&x=0&y=0

If the long link won't work, just go to http://www.wttool.com/ and do a
search on adjustable reamers.

[jerry wass]

DonMorrisey wrote:
> I'm trying to figure out how and where to buy reamers. I need to
> create some 5/8" and 1/2" holes in ultra high molecular weight
> polyethylene blocks for my control system. The aileron push tubes
> slide thorugh the blocks and the aileron actuators mount in the blocks
> as well. The mounting component of my aileron actuator is 5/8", so
> when buying the .6250" reamer is that already slightly oversized? I
> have been told the holes should be oversized by .002". I have looked
> for reamers on line but don't know if what I'm buying is the right
> size, there is little or no description for them.
>
> Can someone tell me what I should look for in buying these tools and
> where may be the best place to do so?
>
> Thanks. Don
>
I'd try drilling the holes with the nominal size drills & then touching
them up with some sandpaper on a dowel..

[GeorgeB]

On 20 Jan 2007 18:40:24 -0800, "DonMorrisey" >
wrote:

>I'm trying to figure out how and where to buy reamers. I need to
>create some 5/8" and 1/2" holes in ultra high molecular weight
>polyethylene blocks for my control system. The aileron push tubes
>slide thorugh the blocks and the aileron actuators mount in the blocks
>as well. The mounting component of my aileron actuator is 5/8", so
>when buying the .6250" reamer is that already slightly oversized? I
>have been told the holes should be oversized by .002". I have looked
>for reamers on line but don't know if what I'm buying is the right
>size, there is little or no description for them.
>
>Can someone tell me what I should look for in buying these tools and
>where may be the best place to do so?

Don, you've already had others say what I'll say, but hole sizes in
UHMW have not, in my experience, matched drill or reamer sizes very
closely as contrasted to metals. It has been my experience, as well,
that taking 0.005 out via reaming UHMW gives a different size hole
than taking 0.030 out. I'm with the camp who suggest adjustable
reamers if you feel the need to ream, otherwise, use a drill and be a
little oversize. Remember that the expansion of materials is
different, binding would not be a good thing.

I'd definitely pre-ream(drill) to a specific size before finish
reaming(drilling). I'd run the tool very slowly and "lube" with only
compressed air.

[Capt. Geoffrey Thorpe]

"GeorgeB" > wrote in message
...
> On 20 Jan 2007 18:40:24 -0800, "DonMorrisey" >
> wrote:
<...>
> little oversize. Remember that the expansion of materials is
> different, binding would not be a good thing.
>

Would you then suggest that it would be a good idea to test the fit of the
sample parts after the plastic and aluminum have spent the night in the
deep-freeze and again after a couple hours in a 150 F. oven (about how hot
it can get with the sun beating on a closed structure?)?

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

[Philippe Vessaire]

DonMorrisey wrote:

> I'm trying to figure out how and where to buy reamers. I need to
> create some 5/8" and 1/2" holes in ultra high molecular weight
> polyethylene blocks for my control system. The aileron push tubes
> slide thorugh the blocks and the aileron actuators mount in the blocks
> as well. The mounting component of my aileron actuator is 5/8", so
> when buying the .6250" reamer is that already slightly oversized? I
> have been told the holes should be oversized by .002". I have looked
> for reamers on line but don't know if what I'm buying is the right
> size, there is little or no description for them.

Remember polyethylene blocks may creep under load.
You need some clearance between hole and tube. I don't think you kneed
to buy a reamer, a new drill will do the job with proper clearance.


By
--
Pub: http://www.slowfood.fr/france
Philippe Vessaire Ò¿Ó¬

[Morgans]

"Philippe Vessaire" > wrote

> Remember polyethylene blocks may creep under load.
> You need some clearance between hole and tube. I don't think you kneed
> to buy a reamer, a new drill will do the job with proper clearance.

To OP: was there a +/- type of allowable clearance given, as a recommended
range?

It would seem like a necessary range of fits would have to be given. As
this poster pointed out, the coefficients of expansion for these two
different materials would be wildly different, and the clearances would have
to change for the temperature spread an aircraft would be subjected to.

I agree that a freezer/oven test needs to happen, and clearances measured,
or at least calculated clearances for the different temperatures.

Anyone got a favorite source for materials expansion coefficients?
--
Jim in NC

[DonMorrisey]

>
> To OP: was there a +/- type of allowable clearance given, as a recommended
> range?
>

Jim, it was suggested that I oversize the hole by .002. There is great
information in this post and I thank everyone for contributing.

Don.

[Bill Daniels]

I have had great results drilling UHMWPE with wood workers Forstner bits.
Just as with wood, these bits cut holes with very straight, smooth sides in
UHMWPE. OTOH, metal twist drills tend to push material aside which then
rebounds to make the hole smaller than the nominal size of the drill. I
replaced the nylon pushrod fairleads in my sailplane with UHMWPE using
Forstner bits to drill the holes slightly bigger than the pushrod OD.

Bill Daniels

"DonMorrisey" > wrote in message
oups.com...
> >
>> To OP: was there a +/- type of allowable clearance given, as a
>> recommended
>> range?
>>
>
> Jim, it was suggested that I oversize the hole by .002. There is great
> information in this post and I thank everyone for contributing.
>
> Don.
>

[Cy Galley]

Reamers as another said just don't work on these self-lubing plastics. It
just pushes away and then springs back. Sharp over size drills some times
work.



"Maxwell" > wrote in message
...
>
> "DonMorrisey" > wrote in message
> oups.com...
>> I'm trying to figure out how and where to buy reamers. I need to
>> create some 5/8" and 1/2" holes in ultra high molecular weight
>> polyethylene blocks for my control system. The aileron push tubes
>> slide thorugh the blocks and the aileron actuators mount in the blocks
>> as well. The mounting component of my aileron actuator is 5/8", so
>> when buying the .6250" reamer is that already slightly oversized? I
>> have been told the holes should be oversized by .002". I have looked
>> for reamers on line but don't know if what I'm buying is the right
>> size, there is little or no description for them.
>>
>> Can someone tell me what I should look for in buying these tools and
>> where may be the best place to do so?
>>
>> Thanks. Don
>>
>
> You might want to consider adjustable reamers Don.
>
> http://wttool.resultspage.com/search?p=Q&ts=custom&uid=956095168&srid=S9-2&nodecode=true&af=&do=search&do=search&w=adjustable+reamers&x=0&y=0
>
> If the long link won't work, just go to http://www.wttool.com/ and do a
> search on adjustable reamers.
>
>
>
>
>

[Maxwell]

Have you tried this style of adjustable reamer in polyethylene?

Adjustable reamers can be preset to any size, thus allowing for any amount
of spring back. You can start by adjusting it to slightly polish a drilled
hole, and just keep adjusting it out, and making additional passes unitl you
get what you want.

If he is trying to hold .002" oversize, an oversized drill is going to be
much less predictable, probably more difficult to find and a good bit more
expensive.

I'll be the first to admit, I don't recall ever using one in polyethylene -
but I have used them with good results in delrin.


"Cy Galley" > wrote in message
news:ArVsh.1152041$084.63830@attbi_s22...
> Reamers as another said just don't work on these self-lubing plastics. It
> just pushes away and then springs back. Sharp over size drills some times
> work.
>
>
>
> "Maxwell" > wrote in message
> ...
>>
>> "DonMorrisey" > wrote in message
>> oups.com...
>>> I'm trying to figure out how and where to buy reamers. I need to
>>> create some 5/8" and 1/2" holes in ultra high molecular weight
>>> polyethylene blocks for my control system. The aileron push tubes
>>> slide thorugh the blocks and the aileron actuators mount in the blocks
>>> as well. The mounting component of my aileron actuator is 5/8", so
>>> when buying the .6250" reamer is that already slightly oversized? I
>>> have been told the holes should be oversized by .002". I have looked
>>> for reamers on line but don't know if what I'm buying is the right
>>> size, there is little or no description for them.
>>>
>>> Can someone tell me what I should look for in buying these tools and
>>> where may be the best place to do so?
>>>
>>> Thanks. Don
>>>
>>
>> You might want to consider adjustable reamers Don.
>>
>> http://wttool.resultspage.com/search?p=Q&ts=custom&uid=956095168&srid=S9-2&nodecode=true&af=&do=search&do=search&w=adjustable+reamers&x=0&y=0
>>
>> If the long link won't work, just go to http://www.wttool.com/ and do a
>> search on adjustable reamers.
>>
>>
>>
>>
>>
>
>

[[email protected]]

Bill Daniels wrote:
> I have had great results drilling UHMWPE with wood workers Forstner bits.
>
> Bill Daniels

I hate it when I forget the obvious :-)
That's how I do it now - and you could dress the cheap bits to any
diameter to get the fit you need. I gave up on the reaming long time
ago. I could never get a consistant hole, even with the adjustables.
Set one large enough to actually do some cutting (over come the spring
back) and it was just as likely to decide to take the full cut every so
often, giving an oversize hole. Freezing the stuff helps.

Bottom line; think wood not metal. Wood working tools work just fine
on this kind of plastic.
======================
Leon

[Morgans]

"Maxwell" > wrote

> If he is trying to hold .002" oversize, an oversized drill is going to be
> much less predictable, probably more difficult to find and a good bit more
> expensive.

The key is the type of bit he is advocating dressing and using.

A wood cutting Forsner style drill bit eliminates any possible springback,
as it cuts only on a straight line from the center to the diameter, and
pretty much level across the hole. It has no flutes to try to dress, and a
small area to dress. It is the ideal bit to re-size.
--
Jim in NC

[Maxwell]

"Morgans" > wrote in message
...
>
> "Maxwell" > wrote
>
>> If he is trying to hold .002" oversize, an oversized drill is going to be
>> much less predictable, probably more difficult to find and a good bit
>> more expensive.
>
> The key is the type of bit he is advocating dressing and using.
>
> A wood cutting Forsner style drill bit eliminates any possible springback,
> as it cuts only on a straight line from the center to the diameter, and
> pretty much level across the hole. It has no flutes to try to dress, and
> a small area to dress. It is the ideal bit to re-size.
> --
> Jim in NC

He didn't say what type of drill bit, and forstner bits do not eliminate any
possibility of spring back, try drilling rubber or felt.

Also, how do you easily resize a forstner bit? Are you sure the others are
not talking
about spade drills?

[[email protected]]

Try KBC Tools. They're on the 'Net, and have a full line of decimal
reamers, which will fit almost any application.

That said, I would chuck the UHMW in a four-jaw chuck on the lathe
and turn the hole using a really sharp HSS bit.

Dan

[Maxwell]

> wrote in message
ps.com...
>
> Try KBC Tools. They're on the 'Net, and have a full line of decimal
> reamers, which will fit almost any application.
>
> That said, I would chuck the UHMW in a four-jaw chuck on the lathe
> and turn the hole using a really sharp HSS bit.
>
> Dan
>

No, ya got lost somewhere Dan. The question at this point is how do you
resize a forstner bit by dressing it, and how could it possibly be the ideal
bit to resize.

[Morgans]

"Maxwell" > wrote

> No, ya got lost somewhere Dan. The question at this point is how do you
> resize a forstner bit by dressing it, and how could it possibly be the
> ideal bit to resize.


Turn down the outside, or grind down the outside. It is a relatively small
height, and all solid, except for one or two small areas.
--
Jim in NC

[Capt. Geoffrey Thorpe]

"Morgans" > wrote in message
...
>
> "Maxwell" > wrote
>
>> No, ya got lost somewhere Dan. The question at this point is how do you
>> resize a forstner bit by dressing it, and how could it possibly be the
>> ideal bit to resize.
>
>
> Turn down the outside, or grind down the outside. It is a relatively
> small
> height, and all solid, except for one or two small areas.
> --
> Jim in NC
>

You are talking about grinding the OD of one of these bad boys?
http://www.woodcraft.com/family.aspx?familyid=8311

Larger picture:
http://www.woodcraft.com/InhancedImage.aspx?FamilyID=8311

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

[Maxwell]

"Capt. Geoffrey Thorpe" <The Sea Hawk at wow way d0t com> wrote in message
news:faOdnWsiTthUryjYnZ2dnUVZ_qGjnZ2d@wideopenwest .com...
> "Morgans" > wrote in message
> ...
>>
>> "Maxwell" > wrote
>>
>>> No, ya got lost somewhere Dan. The question at this point is how do you
>>> resize a forstner bit by dressing it, and how could it possibly be the
>>> ideal bit to resize.
>>
>>
>> Turn down the outside, or grind down the outside. It is a relatively
>> small
>> height, and all solid, except for one or two small areas.
>> --
>> Jim in NC
>>
>
> You are talking about grinding the OD of one of these bad boys?
> http://www.woodcraft.com/family.aspx?familyid=8311
>
> Larger picture:
> http://www.woodcraft.com/InhancedImage.aspx?FamilyID=8311
>
> --
> Geoff
> The Sea Hawk at Wow Way d0t Com
> remove spaces and make the obvious substitutions to reply by mail
> When immigration is outlawed, only outlaws will immigrate.

Thanks Geoff, that is the question on my mind too. If you could even find
one that was 11/16, you would have to pull .030 per side off of it to get an
oversized 5/8. If not, you would have to pull .060 per side off of a 3/4. I
don't see how you could do it without a tool grinder.

[Dan[_2_]]

Maxwell wrote:
> "Capt. Geoffrey Thorpe" <The Sea Hawk at wow way d0t com> wrote in message
> news:faOdnWsiTthUryjYnZ2dnUVZ_qGjnZ2d@wideopenwest .com...
>> "Morgans" > wrote in message
>> ...
>>> "Maxwell" > wrote
>>>
>>>> No, ya got lost somewhere Dan. The question at this point is how do you
>>>> resize a forstner bit by dressing it, and how could it possibly be the
>>>> ideal bit to resize.
>>>
>>> Turn down the outside, or grind down the outside. It is a relatively
>>> small
>>> height, and all solid, except for one or two small areas.
>>> --
>>> Jim in NC
>>>
>> You are talking about grinding the OD of one of these bad boys?
>> http://www.woodcraft.com/family.aspx?familyid=8311
>>
>> Larger picture:
>> http://www.woodcraft.com/InhancedImage.aspx?FamilyID=8311
>>
>> --
>> Geoff
>> The Sea Hawk at Wow Way d0t Com
>> remove spaces and make the obvious substitutions to reply by mail
>> When immigration is outlawed, only outlaws will immigrate.
>
> Thanks Geoff, that is the question on my mind too. If you could even find
> one that was 11/16, you would have to pull .030 per side off of it to get an
> oversized 5/8. If not, you would have to pull .060 per side off of a 3/4. I
> don't see how you could do it without a tool grinder.
>
>
>
If you own a bench grinder, drill press or dremel equivalent make a
bracket out of sheet metal, phenolic or hardwood to hold the tool. It
sounds a tad Rube Goldburgish but it can be done. I made a few for
grinding lathe tools.

In the case of a rotating bit you need symmetry as much as size. It
seems to me you coulduse a wood block drilled to accept the tool shaft
at one end and drilled to make a pivot point at the other. A simple stop
like a machine screw could serve as an adjustable stop.

Visit a machine shop some time, you'll see some rather clever widgets
made for a one time use. You never know, they might have exactly what
you are looking for.

Dan, U.S. Air Force, retired

[Morgans]

"Capt. Geoffrey Thorpe" <The Sea Hawk at wow way d0t com> wrote

> You are talking about grinding the OD of one of these bad boys?
> http://www.woodcraft.com/family.aspx?familyid=8311
>

Yep/ That's the type.

Make a widget to hold a small angle grinder on its side, with a pivot and a
screw for advancing the grinder a bit at a time. Make it so that it will
work clamped to a drill press table.

Put the drill bit in the drill press, and push the bit up and down past the
spinning grinder. Advance the grinder a bit at a time, and stop to check
the progress often.

It works. I've done it before. I am a bit "Rube Goldbergish" at times.
That comes in handy, for a homebuilder.

Of course, if you know someone who works in a machine shop, he could do the
job in a tenth of the time. Where's the fun in that, though?
--
Jim in NC

[Bob Kuykendall]

I have a bit of experience that bears directly on this topic.

A while back I made a bunch of linear guides for a control stick
mechanism that used 5/8" steel push-pull tubes. I tried a bunch of
materials before settling on Nylon.

Anyhow, I found that in practice the smallest reasonable clearance hole
for the 5/8" tube was 1/32" oversize - that's 0.656" decimal or 21/32"
fractional. Any smaller, and the combination of crush and misalignment
used up all of the margin and the tube would bind up in the guide. The
1/32" clearance didn't seem to add any appreciable slop to the system,
and ran with reasoanbly low friction.

Another thing to consider is the that a lot of these low-friction
plastics have pretty steep thermal expansion curves. Also, some of them
absorb water and swell up.

If you have relatively low radial loads and you want really, really low
friction, you can go with these low-cost 5/8" ID linear ball bearings
from ACS:

http://www.aircraftspruce.com/catalog/appages/pushrodguide.php

I use a lot of them (copies of them, actually), and they're really
sweet. Even with a 12-foot aluminum tube run through five of them, the
friction is so low that the tube slides downhill under its own weight
at angles as low as 2 degrees.

Thanks, Bob K.
http://www.hpaircraft.com/hp-24

[Bob Kuykendall]

Oh, I forgot to mention:

In my experience, steel tubing tends to run a little larger than the
nominal size. Commercial steel tube (the 1/16" wall stuff from the
hardware store) tends to run around 0.020" over, 4130 tends to run
about 0.010" over. That can make a big difference in hole clearances.

Bob K.

[Maxwell]

"Morgans" > wrote in message
...
>
> "Capt. Geoffrey Thorpe" <The Sea Hawk at wow way d0t com> wrote
>
>> You are talking about grinding the OD of one of these bad boys?
>> http://www.woodcraft.com/family.aspx?familyid=8311
>>
>
> Yep/ That's the type.
>
> Make a widget to hold a small angle grinder on its side, with a pivot and
> a screw for advancing the grinder a bit at a time. Make it so that it
> will work clamped to a drill press table.
>
> Put the drill bit in the drill press, and push the bit up and down past
> the spinning grinder. Advance the grinder a bit at a time, and stop to
> check the progress often.
>
> It works. I've done it before. I am a bit "Rube Goldbergish" at times.
> That comes in handy, for a homebuilder.
>
> Of course, if you know someone who works in a machine shop, he could do
> the job in a tenth of the time. Where's the fun in that, though?
> --
> Jim in NC

I think you and Dan have had a little too much torpedo juice!

[Dan[_2_]]

Maxwell wrote:
> "Morgans" > wrote in message
> ...
>> "Capt. Geoffrey Thorpe" <The Sea Hawk at wow way d0t com> wrote
>>
>>> You are talking about grinding the OD of one of these bad boys?
>>> http://www.woodcraft.com/family.aspx?familyid=8311
>>>
>> Yep/ That's the type.
>>
>> Make a widget to hold a small angle grinder on its side, with a pivot and
>> a screw for advancing the grinder a bit at a time. Make it so that it
>> will work clamped to a drill press table.
>>
>> Put the drill bit in the drill press, and push the bit up and down past
>> the spinning grinder. Advance the grinder a bit at a time, and stop to
>> check the progress often.
>>
>> It works. I've done it before. I am a bit "Rube Goldbergish" at times.
>> That comes in handy, for a homebuilder.
>>
>> Of course, if you know someone who works in a machine shop, he could do
>> the job in a tenth of the time. Where's the fun in that, though?
>> --
>> Jim in NC
>
> I think you and Dan have had a little too much torpedo juice!
>
>
>
'scuse me, I don't think battery acid is good to drink. I prefer the
good stuff: Pepsi™.

Dan, U.S. Air Force, retired

[Maxwell]

"Dan" > wrote in message
...
> Maxwell wrote:
>> "Morgans" > wrote in message
>> ...
>>> "Capt. Geoffrey Thorpe" <The Sea Hawk at wow way d0t com> wrote
>>>
>>>> You are talking about grinding the OD of one of these bad boys?
>>>> http://www.woodcraft.com/family.aspx?familyid=8311
>>>>
>>> Yep/ That's the type.
>>>
>>> Make a widget to hold a small angle grinder on its side, with a pivot
>>> and a screw for advancing the grinder a bit at a time. Make it so that
>>> it will work clamped to a drill press table.
>>>
>>> Put the drill bit in the drill press, and push the bit up and down past
>>> the spinning grinder. Advance the grinder a bit at a time, and stop to
>>> check the progress often.
>>>
>>> It works. I've done it before. I am a bit "Rube Goldbergish" at times.
>>> That comes in handy, for a homebuilder.
>>>
>>> Of course, if you know someone who works in a machine shop, he could do
>>> the job in a tenth of the time. Where's the fun in that, though?
>>> --
>>> Jim in NC
>>
>> I think you and Dan have had a little too much torpedo juice!
>>
>>
>>
> 'scuse me, I don't think battery acid is good to drink. I prefer the good
> stuff: Pepsi™.
>
> Dan, U.S. Air Force, retired

Torpedo juice was supposed to be alchol. Ref:
http://en.wikipedia.org/wiki/Torpedo_Juice
Don't you remember Buster Keaton drinking torpedo juice in the old Muscle
Beach Party movies.

[Dan[_2_]]

Maxwell wrote:
> "Dan" > wrote in message
> ...
>> Maxwell wrote:
>>> "Morgans" > wrote in message
>>> ...
>>>> "Capt. Geoffrey Thorpe" <The Sea Hawk at wow way d0t com> wrote
>>>>
>>>>> You are talking about grinding the OD of one of these bad boys?
>>>>> http://www.woodcraft.com/family.aspx?familyid=8311
>>>>>
>>>> Yep/ That's the type.
>>>>
>>>> Make a widget to hold a small angle grinder on its side, with a pivot
>>>> and a screw for advancing the grinder a bit at a time. Make it so that
>>>> it will work clamped to a drill press table.
>>>>
>>>> Put the drill bit in the drill press, and push the bit up and down past
>>>> the spinning grinder. Advance the grinder a bit at a time, and stop to
>>>> check the progress often.
>>>>
>>>> It works. I've done it before. I am a bit "Rube Goldbergish" at times.
>>>> That comes in handy, for a homebuilder.
>>>>
>>>> Of course, if you know someone who works in a machine shop, he could do
>>>> the job in a tenth of the time. Where's the fun in that, though?
>>>> --
>>>> Jim in NC
>>> I think you and Dan have had a little too much torpedo juice!
>>>
>>>
>>>
>> 'scuse me, I don't think battery acid is good to drink. I prefer the good
>> stuff: Pepsi™.
>>
>> Dan, U.S. Air Force, retired
>
> Torpedo juice was supposed to be alchol. Ref:
> http://en.wikipedia.org/wiki/Torpedo_Juice
> Don't you remember Buster Keaton drinking torpedo juice in the old Muscle
> Beach Party movies.
>
>
The old torpedoes did burn alcohol. The running gag in McHale's Navy
TV series and many movies is they would drink the stuff. If memory
serves it wasn't safe to drink since it was wood alcohol. The problem
with alcohol burning in torpedoes is you get wakes that can be seen
visually and heard by hydrophones. That's why they went to batteries for
electric drive. That and gyros could be electric instead of pressure driven.

Dan, U.S. Air Force, retired

[Morgans]

"Dan" > wrote

> The old torpedoes did burn alcohol. The running gag in McHale's Navy TV
> series and many movies is they would drink the stuff. If memory serves it
> wasn't safe to drink since it was wood alcohol. The problem with alcohol
> burning in torpedoes is you get wakes that can be seen visually and heard
> by hydrophones. That's why they went to batteries for electric drive. That
> and gyros could be electric instead of pressure driven.

Interesting, but your post made me run to Goggle and investigate. I did not
think batteries were the only thing being used, because we had a very
controversial hazardous waste incinerator nearby, and it burned a LOT of old
torpedo fuel, which was said to be very nasty stuff.

The fuel used since WWII was called OTTO fuel , and later OTTO II fuel. It
of course has its own oxidizer in the fuel.

The history of the torpedo since WWII is split between chemical fuel and
battery power for propulsion. The battery gained ground until the Soviet
subs got so fast that the battery powered torpedoes were not fast enough,
then the chemical fuels came back. The methods of combustion ranged from
steam generation for turbines or jet propulsion, to combustion engines, some
with radical designs like pistons driving external swashplates.

So, if OTTO fuels contain alcohol, I might be guilty of breathing my torpedo
juice.... <g>

Nevertheless, I have done some pretty strange tool modifications, with a
minimum of sophisticated tools at hand.

This was only a crude drill modification. It does not have to be perfect to
work well. Modify, measure, test, repeat as necessary, to get desired
result.

Or was that the instructions on my shampoo? ;-)
--
Jim in NC

[Dan[_2_]]

Morgans wrote:
>
> "Dan" > wrote
>
>> The old torpedoes did burn alcohol. The running gag in McHale's
>> Navy TV series and many movies is they would drink the stuff. If
>> memory serves it wasn't safe to drink since it was wood alcohol. The
>> problem with alcohol burning in torpedoes is you get wakes that can be
>> seen visually and heard by hydrophones. That's why they went to
>> batteries for electric drive. That and gyros could be electric instead
>> of pressure driven.
>
> Interesting, but your post made me run to Goggle and investigate. I did
> not think batteries were the only thing being used, because we had a
> very controversial hazardous waste incinerator nearby, and it burned a
> LOT of old torpedo fuel, which was said to be very nasty stuff.
>
> The fuel used since WWII was called OTTO fuel , and later OTTO II fuel.
> It of course has its own oxidizer in the fuel.
>
> The history of the torpedo since WWII is split between chemical fuel and
> battery power for propulsion. The battery gained ground until the
> Soviet subs got so fast that the battery powered torpedoes were not fast
> enough, then the chemical fuels came back. The methods of combustion
> ranged from steam generation for turbines or jet propulsion, to
> combustion engines, some with radical designs like pistons driving
> external swashplates.
>
> So, if OTTO fuels contain alcohol, I might be guilty of breathing my
> torpedo juice.... <g>
>
> Nevertheless, I have done some pretty strange tool modifications, with
> a minimum of sophisticated tools at hand.
>
> This was only a crude drill modification. It does not have to be
> perfect to work well. Modify, measure, test, repeat as necessary, to
> get desired result.
>
> Or was that the instructions on my shampoo? ;-)

In the 1960s the batteries in some U.S. torpedoes had a tendency to
over heat and were so dangerous they were being recalled and repaired.
Apparently Scorpion's torpedo batteries weren't replaced and a cook off
is suspected in causing the boat's demise.

As for tool modifications I used to be a gunsmith and found it easier
and cheaper to make or modify tools. Then a divorce came along and some
other gunsmith bought 'em up. He would ask me what a tool or widget was
for and I'd tell him about a Schmedlapp Schutzenboomer model
Blowupinthefacen I worked on 20 years before.

Dan, U.S. Air Force, retired

[Blueskies]

"Morgans" > wrote in message ...
:
: This was only a crude drill modification. It does not have to be perfect to
: work well. Modify, measure, test, repeat as necessary, to get desired
: result.
:
: Or was that the instructions on my shampoo? ;-)
: --
: Jim in NC
:

Definitely too much of some kind of juice!

;-)

Dan D.

[Roger (K8RI)]

On Sat, 20 Jan 2007 22:49:56 -0600, "Highflyer" > wrote:

>
>"DonMorrisey" > wrote in message
oups.com...
>> I'm trying to figure out how and where to buy reamers. I need to
>> create some 5/8" and 1/2" holes in ultra high molecular weight
>> polyethylene blocks for my control system. The aileron push tubes
>> slide thorugh the blocks and the aileron actuators mount in the blocks
>> as well. The mounting component of my aileron actuator is 5/8", so
>> when buying the .6250" reamer is that already slightly oversized? I
>> have been told the holes should be oversized by .002". I have looked
>> for reamers on line but don't know if what I'm buying is the right
>> size, there is little or no description for them.
>>
>> Can someone tell me what I should look for in buying these tools and
>> where may be the best place to do so?
>>
>> Thanks. Don
>>
>
>Or, if not MacMaster Carr, Check MHC online. ( Manhattan Supply Company )
>They do an unbelieveable job of stocking every thing in their catalog. I
>once ordered a six foot long length of 1 1/4 inch ACME threaded rod, with
>nuts. It arrived the next day by UPS Ground!
>
>Highflyer
>Highflight Aviation Services
>Pinckneyville Airport ( PJY )
>
>PS: Note, the Pinckneyville 2007 Flyin is coming up May 18, 19, and 20!
>Plan now so you don't miss it. :-)
>
Please drop me a note off list. I seem to have misplaced your old
address. I don't believe you read the one above very often.

Roger (N833R World's oldest Debonair).
any of my old addresses except the rdhalste one will work.