Building a sled, runners from MDF? - Router Forums
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 47 (permalink) Old 08-26-2014, 09:48 PM Thread Starter
Registered User
 
Join Date: Aug 2014
Country: Argentina
First Name: Pablo
Posts: 289
 
Default Building a sled, runners from MDF?

Hi, I had some "fun" trying to make the sled runners from hardwood, seems like the only way to properly make them is to have a planer/jointer or to make them from plywood/MDF.

I wasted some hardwood trying to make them, with no success, the wood was not perfect enough to allow me to use my fence, however, MDF is perfectly flat and in 2 mins I could make two perfect fit runners.

However, I fear that MDF is not a good material for this job.

Any suggestions?.
Artemix is offline  
Sponsored Links
Advertisement
 
post #2 of 47 (permalink) Old 08-27-2014, 12:45 AM
Forum Contributor
 
Stick486's Avatar
 
Join Date: Jan 2013
Country: United States
First Name: Stick
Posts: 29,192
 
Default

Quote:
Originally Posted by Artemix View Post
Hi, I had some "fun" trying to make the sled runners from hardwood, seems like the only way to properly make them is to have a planer/jointer or to make them from plywood/MDF.

I wasted some hardwood trying to make them, with no success, the wood was not perfect enough to allow me to use my fence, however, MDF is perfectly flat and in 2 mins I could make two perfect fit runners.

However, I fear that MDF is not a good material for this job.

Any suggestions?.
go with UHMW or similar...

https://en.wikipedia.org/wiki/Ultra-...t_polyethylene

it's the stuff cutting boards are made out of...
way cheaper as cutting boards too...

This would have been the week that I'd have finished chewing thru the restraints...
If only new layers hadn't been added....

Stick....
Forget the primal scream, just ROAR!!!
"SNORK Mountain Congressional Library and Taxidermy”
Stick486 is online now  
post #3 of 47 (permalink) Old 08-27-2014, 12:51 AM
Registered User
 
MAFoElffen's Avatar
 
Join Date: Jun 2012
Country: United States
First Name: Mike
Posts: 2,369
 
Default

Quote:
Originally Posted by Artemix View Post
Hi, I had some "fun" trying to make the sled runners from hardwood, seems like the only way to properly make them is to have a planer/jointer or to make them from plywood/MDF.

I wasted some hardwood trying to make them, with no success, the wood was not perfect enough to allow me to use my fence, however, MDF is perfectly flat and in 2 mins I could make two perfect fit runners.

However, I fear that MDF is not a good material for this job.

Any suggestions?.
I've made quite a few cross-cut sleds... and I've tried a variety of materials for runners. I'm assuming you are taking about 3/4"x3/8" Miter slots or 5/8"x1/4" slots?

MDF is good left being used as interior panels, carcasses for cabinets, millwork, etc.. If you cut then into thin strips to use as runners, they tend to want to separate and split. When MDF is made, it is pressed together form the sides... and when stress is relieved, as when you cut into thin strips, it wants to come apart in thin paper-like layers. Even if it does stay together, it is not very durable and wears out fast.

I've tried UHMWPE... When cut into strips it wants to flex and bend. When I used that, I cut grooves into the bottom of the sled to mount the miter bars into, to keep them straight. To tell you about the experience, I didn't make any more like it. I have UHMW on me fences and I really like it there, but that is in slots in extrusions, so not the same kind of affair.

Once upon a time (years ago) I thought about plywood... but when you cut plywood into strips, relieving the stress in it, it has a mind of it's own. Very few strips will be even close to being straight. And iif it is off by a smige, a PITA to get down that small amount.

Most of the sleds I still make, I use hardwood or metal bar stock. I've had really good luck with metal key stock... It is durable and I can use nylon set scews to make them adjustable in slots. The metal miter bars are handy, because I can drill and tap the bar stock to screw the sled to the bars. (very strong that way)

But hardwood is cheaper and more readily available. I've had the best luck using scrap pieces of oak and maple hardwood flooring. The best one's I have were made from apitong. (but I had some scrap onhand = too spendy to go out to use just for that...)

Easier with a planer... but not required. Look in my uploads for pic's of one on my TS jointer jigs. I make them in 4' and 8' lengths. I use them as a straight line guide for Circular Saws and a glueup ripping, as a jointer guide or to get a straight cut on rough cut lumber... on my cabinet saw or on my jobsite saws.

Easy to make- A 4 foot long piece of ply wood and a 4 foot long piece of 1x2. Screw the 1x2 to the plywood's factory edge. Take your circular saw, with the wide edge against the edge of the 1x2 and trim the plywood.

You now have a guide with 2 parallel straight edges. If you put a board on top of that with the bow away from the 1x2, the guide with the 1x3 against your fence. You can get a "straight" quality glue edge rip (on your table saw).

I use another strip of plywood on top of this guide with a few toggle clamps to hold strips of flooring to cut strips for miter slots. It's just a lot safer to do it that way. You never have to have your hands or fingers near the blade... and it comes out with very nice cuts.

Glue-edge cuts on dense hardwood, I usually use a 10' or 12" glue-edge rip blade, 40 tooth. With dense hard woods, I can sand them to adjust the fit. Then I wax them. I make enough sleds (often enough) that when I have hardwood scraps that look like they would make good sled miter bars, I put them on a hself with my other alike stock. When I get enough of that, I set up my saw and cut a number of them (using the same setup)... That way, I have them on-hand later when I get in the mood to build some new sleds.

I've got a planer and planing jigs, but to tell the truth, I've never used them for making miter bars. On some metal miter bars, I have ground some bars down that were too tight (with a 7" angle grinder.) Not as easy to make them looser.

There's other ways I make them also. I tried thin strip jigs, but thin strip jigs are usually for shorter stock. On longer stock... a challenge. On my panel saw, not a challenge at all though (very easy).

Hoping that info helps. If you have any other questions, just ask.

"Don't worry, I saw this work in a cartoon once."
"Usually learning skills and tooling involves a progression of logical steps."

Last edited by MAFoElffen; 08-27-2014 at 01:09 AM.
MAFoElffen is offline  
Sponsored Links
Advertisement
 
post #4 of 47 (permalink) Old 08-27-2014, 01:54 AM
Forum Contributor
 
Stick486's Avatar
 
Join Date: Jan 2013
Country: United States
First Name: Stick
Posts: 29,192
 
Default

some tips for using UHMW...

cut it to fit the slot so that slides easily...
under cut the height/thickness by a fuzz...
use ordinary paper, equal numbers of layers on each side, as shims to hold/center the UHMW to the slot.. shim full length..
two layers to a side for a nice snug fit or three layers to side for a tight fit...
install a layer of quality double stick tape to the UHMW...
set your sled in place...
flip the sled over...
drill FLAT bottomed counter sunk holes for truss or pan headed sheet metal screws... K-Laths work really well...
this is what they look like...

Phillips-Truss-Sheet-Metal-Screws-Zinc

if you V bottom the hole, when you install flat headed screws the UHMW expands/spreads/moves and things don't fit right any more..
ditch the paper shims...
reset the sled..
slides nicely.. great!!!
if not, side the sled back and forth a few times...
the table will leave a black mark(s) on the UHMW...
use your shoulder plane laid over to shave one or two thousands and test..
keep at it till your love affair begins..

Veritas® Shoulder Planes - Lee Valley Tools - Woodworking Tools, Gardening Tools, Hardware Supplies

This would have been the week that I'd have finished chewing thru the restraints...
If only new layers hadn't been added....

Stick....
Forget the primal scream, just ROAR!!!
"SNORK Mountain Congressional Library and Taxidermy”
Stick486 is online now  
post #5 of 47 (permalink) Old 08-27-2014, 06:54 AM
Registered User
 
Join Date: Aug 2012
Country: United States
First Name: Dick
Posts: 802
 
Default

I use these UHMW runners. I am quite sure you can find them in Argentina, or have them shipped in. I simply lay coins in the bottom of the miter slot and brad nail the UHMW strips in place. Then turn the sled over and place flat head screws in the UHMW strips. This works very well, and I have never had any trouble with the fit.

UHMW Strip 3/4" X 3/8" X 48" By Peachtree Woodworking - PW1121 - Woodworking Project Kits - Amazon.com

Dick

Where there's a Willis there's a way!
Willway is offline  
post #6 of 47 (permalink) Old 08-27-2014, 10:10 AM
Registered User
 
paduke's Avatar
 
Join Date: Mar 2010
Country: United States
First Name: Bill
Posts: 1,184
 
Default

Ditto on Stick
Cutting boards either UHMW or HDPE
Shoulder plane to kiss the tight spots

Learning is an exciting adventure
paduke is offline  
post #7 of 47 (permalink) Old 08-27-2014, 02:11 PM
Registered User
 
MikeMa's Avatar
 
Join Date: Jul 2006
Country: United States
First Name: Mike
Posts: 1,041
 
Default

I bought a Incra's runner for my sled. It is adjustable for the slot width, and works very well.

-Mike
Visit my woodworking blog: http://madermadeit.com/
MikeMa is offline  
post #8 of 47 (permalink) Old 08-27-2014, 03:15 PM Thread Starter
Registered User
 
Join Date: Aug 2014
Country: Argentina
First Name: Pablo
Posts: 289
 
Default

Thank you guys for all the feedback!, I've found this wood that is used in construction sites here a lot, and it's considered semi-hard: saligna, it's cheaper than pine and a lot harder too.

About the UHMW, not many companies here produce it, I'm trying to get in contact with a couple of them, no answer yet.
Artemix is offline  
post #9 of 47 (permalink) Old 08-27-2014, 04:21 PM
Forum Contributor
 
Stick486's Avatar
 
Join Date: Jan 2013
Country: United States
First Name: Stick
Posts: 29,192
 
Default

Quote:
Originally Posted by Artemix View Post
Thank you guys for all the feedback!, I've found this wood that is used in construction sites here a lot, and it's considered semi-hard: saligna, it's cheaper than pine and a lot harder too.

About the UHMW, not many companies here produce it, I'm trying to get in contact with a couple of them, no answer yet.
it's those knife resistant plastic cutting boards....
kitchen wares department...

This would have been the week that I'd have finished chewing thru the restraints...
If only new layers hadn't been added....

Stick....
Forget the primal scream, just ROAR!!!
"SNORK Mountain Congressional Library and Taxidermy”

Last edited by Stick486; 08-27-2014 at 04:27 PM.
Stick486 is online now  
post #10 of 47 (permalink) Old 08-27-2014, 04:39 PM Thread Starter
Registered User
 
Join Date: Aug 2014
Country: Argentina
First Name: Pablo
Posts: 289
 
Default

I know that in USA you could probably buy UHMW in any kiosk... but here, it's not like that .
Artemix is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Router Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Combining The Incra LS Positoning Systeprem To The Express Sled Jerry Bowen Tools and Woodworking 8 03-11-2014 05:39 AM
coping sled advice dickhob Table-mounted Routing 2 05-18-2012 10:18 AM
New To Forum - Building a Planing Sled Burkdb New Member Introductions 4 11-11-2010 03:30 PM
VIDEO - Shop built Mitering and Crosscut Sled johnwnixon Tools and Woodworking 5 09-06-2009 10:14 AM
Table saw sled.......... Duane867 Tools and Woodworking 5 07-29-2009 07:59 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome